MinBaS-dagen 2007

MinBaS II
Mineral•Ballast• Sten
Område 2
Rapport nr 2.2.5:1
MinBaS II område nr 2 Produktutveckling
Delområde nr 2 Utveckling av industrimineralbaserade produkter
Projekt/Delprojektnamn nr 2.2.5. Coating och malning av industrimineral med Hicom-teknik
Slutrapport
Malning och coating med Hicom-teknik
Eric Forssberg, MISEC AB
Stockholm i april 2011
Sammanfattning
Vid besök hos Hicom- hos Ludovici Australia Pty, Pinkenba, QLD, Australien i oktober 2009
diskuterades torrmalning och coating av industrimineral. Ett projekt med två försöksmaterial
genomfördes. Som försöksmaterial användes kalksten med deltagande av Nordkalk AB och Omya
AB. Försöken genomfördes hos Ludovici i deras försöksanläggning med en Hicom 25 kW utrustad
med vindsikt Comex ACX 200. Försök gjordes med tillsats av stearat som coating kemikalie.
Försöken gjordes andra halvåret 2010. Materialprover har tillställts de deltagande företagen för
analysering och utvärdering som ännu ej är färdig och som kommer att redovisas senare. För
malning och coating ner till 3 à 4 micron fås i en Hicom om 110 kW en kapacitet av något ton per
timme.
Summary
Coating and grinding of industrial minerals was discussed with Hicom at Ludovici Australia Pty,
Pinkenba, QLD, Australia in October 2010. In this project limestone from Nordkalk AB and Omya
AB was used for tests with coating and grinding during the second half of 2010. Samples have been
sent to the participating companies for evaluation. The results from the evaluation are not yet
available and they will be reported later outside the MinBaS framework. A capacity of about one
ton per hour is obtained in coating and grinding to 3 à 4 micron in a Hicom of 110 kW.
Innehållsförteckning - MinBaS proj 2 2 5
Sammanfattning
Summary
Rapport
Bilaga 1. Besök Hicom den 6.10.09
Bilaga 2. Projektförslag. Coating och malning av industrimineral med Hicomteknik, 16.11.09
Bilaga 3. Hicom pilot plant description. 23.05.10
Bilaga 4. Confidential report H-2010. MIS.01. Hicom pilot plant dry grinding trials
on Calcium Carbonate for Misec. Nordkalk PArfill 7 results. 16 September 2010
Bilaga 5. . Confidential report H-2010. MIS.02. Hicom pilot plant dry grinding
trials on Calcium carbonate for Misec AB. Omyacarb 10 results. 25 January 2011.
MinBaS Projekt 2.2.5. Coating och malning av industrimineral med
Hicom-teknik.
1. Inledning.
Hicom-tekniken har utvecklats under lång tid. Från början var fokus på
våtmalning oh ett omfattande utvecklingsarbete genomfördes i Australien. Bland
kända tillämpningar kan nämnas frimalning av diamanter vid off-shore
utvinning. Jag fick första gången kännedom om Hicom tekniken år 1985 och
besökte senare MD Research utanför Sydney, NSW. I oktober 2009 besökte jag
Ludowici Australia, Pty i Pinkenbaa utanför Brisbane, QLD. Reserapporten finns
som bilaga #1. Teknologin hade flyttats och inriktningen var nu på torrmalning
och en kombination med coating för ytbehandling av fyllmedel för termoplast.
På grundval av erfarenheterna från besöket och efter kontakter med företagen
utarbetades ett projektförslag för MinBaS område 2. Detta projektförslag, bilaga #
2 godkändes av styrgruppen och ett slutligt avtal tecknades den 11.2.10.
Två av MinBaS medlemsföretag visade intresse för att deltaga i försöken hos
Ludowci i Brisbane. Detta var Nordkalk och Omya. Försöksmaterial, Parfill 7
skickades från Nordkalk till Brisbane. För Omya anskaffades försöksmaterial,
Omyacarb 10 lokalt i Australien. Efter undertecknande av sekretessförbindelser
beslöts att försöken skulle genomföras under vecka 31 , 2-6 augusti 2010. Per
korrespondens hade erforderlig tid för försöken diskuterats och en vecka
bedömdes som tillräckligt för två material. Malningsförsök skulle genomföras
med och utan coating.
Försöksanläggningen för Hicom hos Ludowici är påkostad och beskrivs i bilaga #
3. I princip består anläggningen av en Hicom kvarn storlek 25 kW och en vindsikt
typ COMEX ACX 200. I övrigt finns utrustning för pneumatisk transport,
dammavskiljning, provtagning och en Insitec partikelstorleksanalysator. För
matning av stearinsyra finns utrustning för smältning och pumpning. Styrsystem
och datainsamlingssystem kompletterar utrustningen.
2. Försökens genomförande och resultat.
Det stod klart på ett tidigt stadium att försöken inte skulle kunna genomföras
under vecka 31 2010. Praktiskta problem uppträdde med materialhantering och
matning av stearinsyra. Den ledning som skulle föra smält stearinsyra till
kvarnen var inte tillräckligt isolerad varvid materialet stelnade och blockerade
ledningen. Ett litet antal försök med Parfill 7 hanns med under vecka 31 och
resten av försöken genomfördes under hösten 2010. Jag fick tillfälle att besöka
Brisbane ytterligare en
gång under perioden 6-10 september 2010 för deltagande i XXV International
Mineral Processing Congress, IMPC. Jag besökte då Ludowici en gång för att
diskutera försöken inom MinBaS med Dr Steve Marshall och ytterligare en gång
tillsammans med Dr Andreas Fredriksson från LKAB , på den tiden
representerande Minelco. Andreas Fredriksson hade tidigare visat intresse för att
deltaga i MinBaS försök men av olika anledningar hade detta ej blivit av.
En rapport över försöken med Parfill 7 erhölls i slutet av september 2010, bilaga #
4. En rapport över försöken med Omyacarb 10, bilaga # 5 erhölls i slutet av
januari 2011.
Försöksresultaten har kommenterats i bilagorna # 4 och 5. Försöksresultaten visar
att det är svårt att mala utan malhjälpmedel och att det är möjligt att komma ner
till till 97 % mindre än 3 à 4 micron. För en fullstor anläggning skulle kapaciteten
för en Hicomkvarn om 110 kW bli något ton per timme. Det rekommenderas att
två Hicom kvarnar kombineras med en vindsikt.
3. Fortsatt arbete.
Ett stort antal prover från malning med såväl Omyacarb 10 som Parfill 7 har
skickats till Omya respektive Nordkalk för utvärdering som fyllmedel för
termoplast.
Några resultat från dessa utvärderingar föreligger ej ännu. En separat rapport
kommer att presenteras senare.
MinBas har betalat Ludowici cirka 45 000 kronor för försöken. Ludowicis
egeninsats uppgår till cirka 390 000 kronor.
Åkersberga den 7.2.11.
Eric Forssberg
Misec AB
Bilaga 1
Besök Hicom den 6.10.09,
Ludowici Australia Pty, Ltd.,Pinkenba, QLd (Brisbane)
Kontakt:,Dr Steve Marshall, manager Hicom technologies,
Hicom är sedan kort tid en del av Ludowici. Ludowici tillverkar diverse utrustning för
mineralberedning som vibrationssiktar och avvattningscentrifuger. Andra intressanta
områden är slitbeläggningar av kalcinerad bauxit med resin och keramiska plattor som
klistras. För slitbeläggningar i rörledningar rullas slitmaterial och resin inne i röret. Ludowici
gör också polyuretan detaljer för t ex siktar. I Brisbane sker montering och målning.
Maskinbearbetning sker huvudsakligen genom lego eller t ex i Indien. Försöksanläggningen
för Hicom har flyttats från Sydney till Brisbane i slutet av 2008. Steve Marshall var den enda
som kom med. Han anser att man nu har en mer kommersiell verksamhet jämfört med då
R&D finansierades av Charles Warman. Det ultimata syftet för Charles Warman var att skapa
en utrutning med hög energitäthet som kunde användas under jord för frontnära malning.
Tidigare låg fokus på våtmalning t ex för diamanter i marine deposits. Där gällde det att mala
ner snäckskal som spred röntgenstrålning på ungefär samma sätt som diamanter och
följaktligen förhindrade XRF sorting. En annan fördel med Hicom var att den genom de små
dimensionerna kunde placeras ombord på fartyg.
Nu är fokus på torrmalning av Industrial minerals. En typisk anläggning består av 2 stycken
Hicom om 110 kW, vilket är maxstorleken och en vindsikt. Vindsiktarna kan vara dels Comex
, dels Hosokawa. Pilotanläggningen i Brisbane är uppställd med en Comex vindsikt. Man vill
leverera hela anläggningar med Hicom, transportutrustning steel work, styrsystem och
vindsikt. Pilotanläggningen har för övrigt en Insitec partikelanalysator on line. Tidigare
användes rubber lining i Hicom men denna höll inte länge i våtmalning förmodligen på grund
av de höga krafterna och den höga temperaturen. Kylning av varmt gods på grund av den
höga energiintensiteten är fortfarande ett problem. Steve Marshall visade hur man genom
att ta upp ett hål i manteln kunde kyla effektivt. En annan möjlighet att kyla materialet är att
tillföra vatten men det är ej så praktiskt. Typiska temperaturer kan vara 90 grader C.
Nu användes steel lining bestående av white iron, (gjutjärn) och det går bra även för abrasiva
material som SiC. En steel lining kan räcka ett år jämfört med gummi kanske en månad.
Steve Marshall anser att man nu kommit över olika mekaniska problem som tidigare
förekom. För att abrasion inte skall vara något problem krävs att ingående inte är för grovt.
Ett ingående om cirka 50 mikron går bra. Vore det 1 mm skulle det blir slitageproblem.
En målsättning enligt Steve Marshall nu är att marknadsföra Hicom som ett system för
malning och coating av fyllmedel för plast. Med två Hicom och en klasserare torde man
kunna producera 2* 750 kg coatad filler, t ex CaCO3 per timme för termoplast.
Energiförbrukningen blir lägre än för den nu använda tekniken med våtmalning, torkning och
coating. Investeringskostnaden för en sådan anläggning blir ungefär MAUD 2 komplett. En
Hicom svarar för AUD 650 000. Däremot måste sägas att Hicom bara för malning inte är
särskilt energieffektiv . Coating med steric acid. Denna finns i en behållare som värms så att
stearinsyran smälter och sedan användes en pump för att spraya kemikalien. Ungefär 10
Hicom anläggningar är i drift. Exempel på material är:
Zirkon
Kiselkarbid
Talk
CaCO3
Silika
Mica
Baryt
Fly ash
Kaolin
Diamantmalm
För t ex Zirkon är det möjligt att uppnå D97 2,4 mikron och för CaCO3 D97 = 3.5 mikron.
För torrmalning utan coatingsyfte måste oftast grinding aids i form av tex EDTA tillsättas,
kemikalier väljs efter vilket mineral som skall malas.
Det finns sedan rätt länge en Hicom hos Sintef i Trondheim. För ett MinBas projekt är det
mer ändamålsenligt att göra försöken i Brisbane.
Som malmedia kan material ner till 1 mm användas. Normalt är dock 2,5 mm. Vanligen
användes yttriumstabiliserad zirkoniumoxid eller stål. Aluminiumoxid blir för sprött och slås
sönder snabbt vid den höga impacten. Media kostar storleksordningen USD 40 per kg. Detta
kan verka högt men det går inte åt mer än 170 kg media för hela chargen i en 110 kW
maskin.
Styrning av malfinlek sker genom:
Uppehållstid
Öppen utmatningsyta
Mediastorlek
Fyller man Hicom med mer media blir det snarare fråga om skrubbning än om malning.
Vad som verkligen sker inne i Hicom vet man inte så mycket om. Det finns DEM modeller och
PBM .
CSIRO har gjort CFD simuleringar som visar kulornas rörelser.
Vid t ex malning av mica och kaolin fås förmodligen en viss delaminering men det är osäkert.
För kaolin fås en bättre liberation och därmed ökat utbyte.
Andra material som skulle kunna vara intressanta för ett MinBaS projekt vore magnetit.
För försök med pilotanläggning får man räkna med 1 à 2 ton material och upp till fyra dagars
arbete. Kostnaden är AUD 2000 per dag men då ingår även rapport.
Steve Marshall skall skicka en hel del material på CD:
Presentation
Technical data
Particle size distribution
Movies
Pictures
Steve Marshall skall göra en round the world trip I februari/mars 2010 och besöker då gärna
intresserade företag.
File name ”Hicom6.10.09”
Bilaga 2
HICOM Projektförslag 16.11.09
Coating och malning av industrimineral med Hicom-teknik.
1. Inledning
Hicomtekniken utvecklades på 1980-talet. Målsättningen var att ta fram teknik för
malning med hög energiintensitet. Hicom karakteriseras av att malningen sker i
en behållare fylld med malkroppar och att denna är upphäng och utför en
nuterande rörelse. www.hicom-mill.com .
Utvecklingsarbetet bedrevs i stor skala i Sydney, NSWoch finansierades av
Charles Warman. (Warman pumps).
Ett litet antal Hicom-anläggningar såldes framför allt för våtmalning av marina
diamantförande material.
Hicom teknologin har 2008 övertagits av Ludowici Australia Pty. Ltd med
anläggningar i Brisbane, Australien.
En ny försöksanläggning har satts upp och focus har ändrats från våtmalning till
torr malning och behandling. En mycket intressant applikation är coating och
malning av industrimineral. Ytterligare information framgår av Eric Forssbergs
rapport från besök den 6.10.09.
Ett projekt föreslås omfattande coating och malning av ett à två utvalda
industrimineral vid Hicoms anläggning i Brisbane. Proverna skickas tillbaka till
de deltagande företagen för utvärdering och en sammanfattande rapport
utarbetas.
2. Målsättning.
Målsättningen med det föreslagna projektet är att utvärdera och bedöma
Hicomteknikens potential för malning och coating av filler.
3. Projektets genomförande.
Projektet genomföres av Eric Forssberg, Misec AB. Projektet omfattar följande
moment:
1. Val av försöksmaterial i samråd med deltagande företag.
2. 500 à 1000 kg försöksmaterial, mindre än 50 micron skickas till Hicom i
Brisbane
3. Försök med coating och malning vid Hicom i Brisbane.
Partikelstorleksfördelning bestämmes med befintlig Insitec-utrustning.
Försöksparamterar är uppehållstid, avskiljningsgräns för vindsikt, typ COMEX,
mediastorlek, öppen utmatningsyta, koncentration av coatingkemikalie.
Energiförbrukningen bestäms.
4. Prover tas ut och skickas för undersökning hos deltagande företag.
5. Sammanställning av försöksresultat och värdering av tekniken dels med
avseende på malning, dels för coating och produktutveckling av filler.
4. Kostnader för projektets genomförande.
Projektet beräknas kunna genomföras inom en kostnadsram av kronor 305000
Enligt nedanstående specifikation.
1.
2.
3.
4.
5.
6.
Uttag av prover, analysering och frakt till Brisbane, naturainsats 50000
Kostnad för försök vid Hicom AUD 10000, kontant
60000
Rese- och uppehållskostnader, kontant
45000
Analysering av prover vid deltagande företag, naturainsats
50000
Arbetskostnad för Eric Forssberg, kontant
50000
Arbetskostnad för Eric Forssberg, naturainsats
50000
Summa projektkostnad
305000
Kontant
Naturainsats
5. Tidplan
Projektet beräknas kunna genomföras under tiden 1.1.10 – 30.9.10.
Hicom projförslag 16.11.09
155000
150000
Bilaga 3
CONFIDENTIAL
Hicom pilot plant Description
Hicom_Pilot_Plant_Description[2]
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Contents
Hicom 25 Dry Pilot Plant: Description and Operating Procedures .......................................................... 3
Typical Test Procedure .................................................................................................................... 4
Grinding circuit behavior and sampling .......................................................................................... 6
Data Analysis Procedures ........................................................................................................................ 8
Test conditions .................................................................................................................................... 8
Feed and product rate ......................................................................................................................... 8
Circulating load ratio estimation ....................................................................................................... 10
Author:
Dr. Steve Marshall
Report Date:
23rd May 2010
Hicom_Pilot_Plant_Description[2]
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CONFIDENTIAL
Hicom 25 Dry Pilot Plant: Description and Operating Procedures
Figure 1
Photograph showing the Hicom 25 dry pilot plant
The Hicom 25 dry pilot plant is shown in the above picturAe (Figure 1) Figure 1and schematically in
Figure 2 below. The plant consists of a Hicom 25 kW mill with variable speed drive, operating in
closed circuit with a Comex ACX200 high efficiency air classifier. The entire plant is controlled and
monitored using a Siemens S7-300 PLC and Siemens WinCC SCADA package operating on a touchpanel PC mounted in the main control cabinet.
A 75 mm screw feeder is used to transport material to the mill from a feed bin. Solids feed rate to
the mill is calculated from loss-in-weight measurement from a load cell on the feed hopper. The
calculated rate can be used in closed loop with the screw feeder VSD to provide feed rate control.
The Hicom 25 mill motor is controlled by a Siemens VSD in the main control cabinet. The mill is
generally operated at discrete speeds of 760 and 960 RPM corresponding to maximum chamber
acceleration of 30 and 50 G respectively. The mill drive lubrication system is monitored and
controlled by the central Siemens PLC.
The grinding system operates under vacuum in order to avoid dust emission. Material is drawn
through the mill and pneumatically conveyed to the classifier. The air flow required for effective
pneumatic transport through the mill is much less than that required for effective classification.
Therefore, additional air is drawn into the system through the primary air valve indicated on Figure
A1.1. The setting of this valve and the secondary air valve also control the differential pressure across
the mill – that is the mill vacuum.
Oversize particles, rejected by the classifier rotor, fall by gravity down the oversize chute for regrinding in the mill. The classifier is operated by a VSD which allows the rotor speed to be set to
achieve a precise product top cut size. Compressed air is used to seal both the classifier rotor and the
Hicom_Pilot_Plant_Description[2]
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rotor bearings. The classifier oversize return is sealed by a 150 mm double-butterfly valve air lock
system as indicated on the diagram. The secondary air flow to the classifier is manually adjusted by a
butterfly valve, and monitored by an orifice-plate flow meter.
Air and fine product are pneumatically transported to a Torit-DCE DLM V20/12B Dalamatic dust
collector where the product is collected in a drum or bulker bag. The dust collector is sealed by a
200 mm double-butterfly valve air lock system.
An Insitec on-line particle size analyser is installed on the classifier fine-product line. This enables
instant feedback on classifier performance and provides the means for meeting precise particle size
specifications by automatic adjustment of classifier rotor speed.
Two blowers operated in parallel are used to generate the system air flow. A Rietschle SAP1500
(System Blower 2) is run at full speed, and a GAST R93150A (System Blower 1) is operated by a VSD
to provide trim control on system air flowrate in closed-loop feedback with an orifice-plate flow
meter downstream of the dust collector. The total system air capability is roughly 1600 m3/hr at 20 kPa using both blowers.
Instrumentation is incorporated for monitoring critical process and mill control parameters, most of
which are recorded on the SCADA system. The mill power draw is determined from direct reading of
the Mill VSD.
A microwave mass-flow indicator installed on the classifier feed (mill discharge) line provides
feedback as to whether the plant is at steady state.
The grinding chamber nominal volume is 10.7 L and its 40 mm discharge ports are positioned at the
circle of maximum diameter. Grates are placed over the discharge ports to retain the media inside
the grinding chamber. The grate slot width is generally selected at least one-half the diameter of the
smallest media particle used.
Typical Test Procedure
After every chamber change-out, or after an extended shutdown, the mill is operated for twenty
minutes with an empty chamber to establish the no-load power. The required charge of media is
added to the mill before commencing each test. The solids feed rate to the mill is selected, and the
system and secondary air flows set to maintain appropriate classifier conditions. The classifier rotor
speed is then adjusted to give the desired cut size based on Insitec particle size readings.
Product and recycle samples are taken once relatively steady-state plant operation is obtained, as
indicated by the mill discharge mass flow indicator. This is generally 20 to 25 minutes after starting a
run. Critical mill control and process parameters are monitored during each run and recorded on a
standard log sheet every time a sample is taken.
The recirculating load rate is estimated after taking a physical sample of the mill discharge after a
crash stop of the plant. The particle size distributions of the classifier feed, fine product and coarse
reject streams can be used to back-calculate the recirculating load ratio.
The rate of product discharge from the dust collector is calculated from gain-in-weight measurement
of the product bulk bag, which is positioned on electronic weigh-scales.
Hicom_Pilot_Plant_Description[2]
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F T F IC
PI
IN SITEC
FI
PI
D UST
C OL LEC TOR
2 0 0 NB
M
VSD
IA
15 0 N B
PI
COM MEX
ACX 200
CLASSIF IER
FI FT
PI
PI
M
V S D JT
JI
SY ST E M
BL OW E R 1
LOAD C ELL
FI FT
FEED
H OPPER
SE C ON DA R Y A IR V ALV E
PI
W
VSD
M
1 0 0 NB
F IC
F IN E PR OD U C T
C OL LEC T I ON
JT V S D
1 0 0 NB
JI
FI
M
TS TI
PI PT
H ICOM 25
MIL L
PE BB LE T R AP
Figure 2
Hicom Report PE-0816.P-1 (Revision 1)
PR IM A RY A IR V ALV E
Schematic diagram of the Hicom 25 dry pilot plant
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This rate is compared with the feed rate to assess whether the circuit is at steady state. Generally,
the feed and measured product rates must be within 20% of one another, otherwise the data is from
the run is not considered for analysis. The exception to this rule is when the material is very fine or
sticky and there is significant holdup of material in the dust collector. Under such conditions,
accurate determination of product rate is not possible over a short time period, and we rely on
microwave sensor readings of the circulating load to determine if the plant is at steady state.
The mill net power draw for calculation of specific mill grinding energy is determined as the
difference between the measured gross power and the no-load power.
Grinding circuit behavior and sampling
Typical circuit responses for dry pilot plant operation and the test protocol followed are best
illustrated with reference to Figure 3 below, which shows a characteristic SCADA trend obtained
during a pilot plant trial.
Figure 3
Hicom 25 pilot plant SCADA Trend screen
Between 5:54 pm and 6:10 pm, the mill power draw (red trace) was around 11 kW, the circulating
load (black trace) was below 10% and the mill exit temperature (light blue trace) was around 72oC.
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The feed rate (oscillating blue trace) was increased slightly at around 6:10 pm. This resulted in an
increase in circulating load, a decrease in mill power and a decrease in mill temperature due to the
increased rate of heat removal from the mill from the higher solids throughput.
Despite the increased circulating load, the circuit is nevertheless stable as the circulating load is not
increasing above 15-20% on average.
This indicated level of circulating load was considered the maximum stable level for plant operation
with ATH. Experience showed that further increases in feed rate resulted in accelerating increase in
circulating load rate due to the fact that the rate of fresh feed to the mill started to exceed the rate
of fine particle production.
The objective in pilot plant trials was to adjust conditions such as discharge port open area, mill
vacuum, media size and quantity and other factors to try and maximize the mill feed rate before an
excessive circulating load rate was reached.
In the example shown in Figure 3, at around 6:36 pm, the plant was stopped (crash stop) by stopping
the mill, air blowers, the classifier and by shutting the classifier return air lock valves. This way, a
‘snap shot’ was taken of the circuit from which samples could be taken for analysis. We sampled the
recycle stream, the residual powder on the internal walls of the mill body (equivalent to classifier
feed) and also the fine product collected in the product filter. These samples were used to estimate
recirculating load ratio, as outlined in Appendix B.
For some runs, the mill contents were also removed and the powder and grinding media separated
by screening. This way it was possible to determine the holdup level of powder in the mill and also to
assess media wear.
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Data Analysis Procedures
Test conditions
All of the data logged on the SCADA system is collated into an Excel spreadsheet. Where necessary, a
simple first order filter can be applied to smooth the data for more accurate estimation of parameter
values at the time of sample collection or crash stop.
Feed and product rate
For most test runs, estimation of feed and product rate is done by calculating the numerical
derivative of the recorded change in weight of the feed hopper and the product weigh scales
respectively. First-order filtering before and after numerical differentiation is used to reduce the
affect of inherent ‘noise’ in the data.
Generally, the feed rate data is considered more reliable as hold up of material in the product filter
meant that the change of measured product weight with time is usually not a smooth progression.
An algorithm was introduced into the PLC program to calculate the feed rate in real time. However,
because of the long lag times necessary to achieve a smooth output, and a periodic variation in screw
feeder output, use of this calculated rate to control the screw feeder can cause oscillation in the
controlled feed rate.
It is noted that these oscillations do not significantly affect process operation as they are usually
dampened by the relatively high circulating load in the grinding and classification circuit.
Typical rate calculation results are illustrated in Figure 4 below.
Figure 5 shows the corresponding process parameters of mill air temperature (discharge
temperature), mill power and circulating load corresponding to the same time period of the data in
Figure 3 and Figure 4. In this example, it can be seen that a relatively small increase in average feed
rate from around 58 kg/h to around 62 kg/h resulted in a significant increase in circuit load and it was
concluded that further increase was not possible beyond around 62 kg/h for this particular mill and
plant configuration.
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CONFIDENTIAL
Calculated Feed rate (filtered)
Feed rate (PLC output)
Feed Hopper Weight (raw)
Feed Hopper Weight (filtered)
100
620.0
90
600.0
80
70
580.0
50
560.0
WT (kg)
RATE (kg/h)
60
40
540.0
30
20
520.0
10
0
500.0
19/03/2010 16:00
19/03/2010 17:00
Figure 4
19/03/2010 18:00
Hicom 25 pilot plant feed rate estimation example
Air Temp
Mill Power
Circulating Load
80.0
70.0
60.0
50.0
40.0
30.0
20.0
10.0
0.0
19/03/2010 16:00
Figure 5
19/03/2010 17:00
19/03/2010 18:00
Process parameters corresponding to the time periods shown in Figure 3 and Figure 4
Hicom_Pilot_Plant_Description[2]
23-May-2010
Page 9 of 10
CONFIDENTIAL
Circulating load ratio estimation
The circulating load ratio, hence coarse recycle rate, can be estimated from the particle size
distribution of samples of classifier feed, fine product and coarse reject. The Excel solver function is
used to minimize the sum of squares of the difference between measured particles size distribution
and the corresponding particle size distribution calculated using an assumed ratio and the other two
distributions. Generally, the measured classifier feed is considered the least accurate of the collected
samples and this is then taken as the basis for the estimation procedure.
In the example shown in Figure 6 below, it can be seen the calculated and measured classifier feed
distribution closely match, which gives a high level of confidence in the ratio of 6.6 calculated for this
particular test run.
Calculation of the ratio using the coarse return and the fine product was also done to verify accuracy
of the primary estimate. In most cases, variation in calculated values was less than 10%.
The coarse recycle rate was then obtained by multiplying the steady state feed rate by the estimated
recirculating load ratio.
For those trial runs where no crash-stop samples were collected, the ratio may be estimated from
the recirculating load level indicated on the microwave sensor output. Such estimates are considered
accurate only within 20%.
Measured classif ier f eed
Measured coarse reject
Calculated Classif ier Feed
Measured f ine product
100
90
80
% Undersize
70
60
50
40
30
20
10
0
0.1
1
10
100
Size (µm)
Figure 6Results from estimation of recirculation load ratio (RLR) using sum of squares error (SSE)
minimization on adjustment of the calculated classifier feed particle size distribution
Hicom_Pilot_Plant_Description[2]
23-May-2010
Page 10 of 10
Bilaga 4
CONFIDENTIAL
Confidential Report H-2010.MIS.01
Hicom pilot plant dry grinding trials on
Calcium Carbonate for MISEC:
Nordkalk Parfill 7 results
H-2010.MIS.01 R0
16-September-2010
Page 1 of 28
CONFIDENTIAL
Contents
Executive Summary for MISEC ............................................................................................................ 4
1
Introduction ................................................................................................................................ 5
2
Objectives ................................................................................................................................... 5
3
Conclusions & Recommendations ............................................................................................... 5
4
Equipment and procedures ......................................................................................................... 7
4.1
Hicom 25 pilot plant ............................................................................................................ 7
4.1.1
5
Sample / run labelling .................................................................................................. 7
4.2
Particle Size Measurement ................................................................................................ 7
4.3
Data analysis ....................................................................................................................... 7
Test results & discussion ............................................................................................................. 8
5.1
Feed material particle size distribution ................................................................................ 8
5.2
Pilot plant results................................................................................................................. 8
5.2.1
Product size 3-4 µm (P97) - Table 2 ............................................................................ 12
5.2.2
Product size 5-6 µm (P97) - Table 3 ............................................................................ 14
5.2.3
Product size 8-9 µm (P97) - Table 4 ............................................................................ 15
5.2.4
Product size versus specific grinding energy ............................................................... 15
5.3
Scale-up and Hicom 110 production capacity ..................................................................... 17
5.4
Comments on production plant design .............................................................................. 17
Appendix A – Hicom 25 Dry Pilot Plant: Generic Description and Operating Procedures .................... 19
Generic Description of the plant.................................................................................................... 19
Stearic acid dosing system ............................................................................................................ 21
Typical test procedure................................................................................................................... 23
Grinding circuit behaviour and sampling ....................................................................................... 23
Appendix B – Data Analysis Procedures............................................................................................. 25
Test conditions.............................................................................................................................. 25
Feed and product rate................................................................................................................... 25
Circulating load ratio estimation ................................................................................................... 25
Figures
Figure 1
Nordkalk Parfill 7 feed size distribution compared with customer standard ....................... 8
Figure 2
Example of changing product size with change in classifier solids loading......................... 13
H-2010.MIS.01 R0
16-September-2010
Page 2 of 28
CONFIDENTIAL
Figure 3
Product size distributions from the finest uncoated (Run 2) and coated (Run 3)
product samples .............................................................................................................. 13
Figure 4
Example of product size control by automatic regulation of classifier speed..................... 14
Figure 5
PSD for intermediate coated product (Run 6) ................................................................... 15
Figure 6
PSD for coarse coated product (Run 9) ............................................................................. 16
Figure 7
Product size as a function of specific grinding energy – all data ........................................ 16
Figure 8
Projected Hicom 110 kW production rate as a function of product size ............................ 18
Figure 9
Photograph showing the Hicom 25 dry pilot plant ........................................................... 19
Figure 10 Schematic diagram of the Hicom 25 dry pilot plant .......................................................... 20
Figure 11
Hicom pilot plant stearic acid dosing system – reservoir and gear pump ........................ 22
Figure 12
Hicom pilot plant stearic acid dosing system – controls and dosing line .......................... 22
Figure 13 Hicom 25 pilot plant SCADA Trend screen ........................................................................ 24
Figure 14 Hicom 25 pilot plant feed rate estimation example.......................................................... 26
Figure 15 Process parameters corresponding to the time periods shown in Figure 13 and
Figure 14 ......................................................................................................................... 26
Figure 16 Results from estimation of recirculation load ratio (RLR) using sum of squares error
(SSE) minimization on adjustment of the calculated classifier feed particle size
distribution...................................................................................................................... 27
Tables
Table 1
Preferred Hicom mill grinding conditions for Nordkalk Parfill 7 ............................................ 5
Table 2
Summary of results for production of 3-4 µm material ........................................................ 9
Table 3
Summary of results for production of 5-6 µm material ...................................................... 10
Table 4
Summary of results for production of 8-9 µm material ...................................................... 11
Author:
Dr. Steve Marshall
Report Date:
18th September 2010
Revision No:
0
Comments:
Initial release for review by customer
H-2010.MIS.01 R0
16-September-2010
Page 3 of 28
CONFIDENTIAL
Executive Summary for MISEC
A series of trials was undertaken on Nordkalk Parfill 7 in the Hicom pilot plant to demonstrate the
concept of simultaneous grinding of calcium carbonate and coating with stearic acid in the one
process. Stable plant operation was achieved for manufacture of a range of coated product sizes and
provided a high degree of confidence in scale-up of the concept.
Reliable data on product size as a function of specific grinding energy, and projected Hicom 110 kW
mill production capacity as a function of product size was obtained and is presented in this report.
It is recommended that Nordkalk undertake their own particle size analysis and evaluation of other
powder properties on selected bulk samples generated during this test work.
H-2010.MIS.01 R0
16-September-2010
Page 4 of 28
CONFIDENTIAL
1 Introduction
Hicom was approached by Prof. Eric Forssberg, principal of MISEC with a view to understanding more
about current developments on the Hicom mill. During the course of discussions held in our Brisbane
facility, it was explained that Hicom had recently developed a method for simultaneous grinding
calcium carbonate and coating with stearic acid. Following this initial meeting, Prof. Forssberg
garnered interest from Nordkalk and OMYA SE in undertaking test work in the Hicom pilot plant on
their specific materials. This was done under the auspices and sponsorship of the MinBas group to
evaluate the technical and economic case for using new technology in Scandinavian mineral process
plants.
It was agreed that the present Hicom test work would be undertaken for MISEC who would be acting
on behalf of MinBas. This report is therefore directed to MISEC.
The first material received for testing was one metric ton of Nordkalk Parfill 7 calcium carbonate
from Finland. As there were no target size requirements or particle properties specified, the first
series of tests was undertaken as a generic proof-of-concept exercise to demonstrate the capabilities
of the Hicom process.
The purpose of this report is to present results from this first series of trials on the Nordkalk material.
The participation (and patience) of Prof. Forssberg during the initial stages of testing is gratefully
acknowledged.
2 Objectives
Specific objectives of the test work were as follows:
1. Determine suitable conditions for processing Parfill 7 in the Hicom Mill.
2. Estimate mill grinding energy and corresponding production capacity for a Hicom 110 kW mill
over a range of coated product sizes.
3. Provide test samples for evaluation by Nordkalk.
3 Conclusions & Recommendations
1. Table 1 below outlines the mill grinding conditions established as being suitable for this
application
Table 1 Preferred Hicom mill grinding conditions for Nordkalk Parfill 7
Feed
Mill
Mill speed, rpm
Mill filling, vol %
Media Mass, kg
Media type
Media SG, kg/L
Media size, mm
Liners
H-2010.MIS.01 R0
Parfill 7 D97=74 µm
Hicom 25 Pilot Plant
Hicom 110 Production Mill
760
600
50
60
19.0
175
Ce-TPZ (Zirconox, India)
Ce-TPZ (Zirconox, India)
6.1
6.0
1.2-1.4 mm
1.4-1.8 mm
440C Stainless Steel
15/3 Cr/Mo Cast Iron
16-September-2010
Page 5 of 28
CONFIDENTIAL
2. Mill grinding energy and production capacity estimates are provided in sections 5.2.4 (p. 15)
and 5.3 (p. 17) of this report.
3. Bulk product samples (5-15 kg) were collected for all test runs. It is suggested that Nordkalk
evaluate properties of selected samples from the best runs from each of the three product
size groups evaluated. At this stage evaluation of product samples from Runs 2, 3, 6 and 9
would be recommended.
H-2010.MIS.01 R0
16-September-2010
Page 6 of 28
CONFIDENTIAL
4 Equipment and procedures
4.1 Hicom 25 pilot plant
The Hicom 25 dry pilot plant employed for this test work is described in detail in Appendix A. The
grinding media was ‘Zirconox’ Ce-TPZ ceramic media (Jyoti, India). Further details of the operating
conditions are provided in Section 5.
4.1.1
Sample / run labelling
Each test run sample is given a number, as detailed in the table below:
Sample Number –
1st part
Sample Number –
2nd Part (example)
Description
Pilot Plant Tests on Nordkalk Parfill 7 – 1st series
NOR.P.A.001
-F
Feed material designation
-1AP
Run/Sample 1A Product (Classifier Fines)
-1AD
Run/Sample 1A Mill Discharge (Classifier Feed)
-1AR
Run/Sample 1A Recycle (Classifier Coarse Reject)
This labelling convention relates primarily to spreadsheet data and physical samples where provided.
In this report, run numbers are given without the first part prefix.
Generally, ‘A’ and ‘B’ samples refer to duplicate samples taken at the same run condition. In one case
here – Run 5 – the results for A and B samples taken five minutes apart are included to demonstrate
consistency of the data.
4.2 Particle Size Measurement
Feed and product sizing were measured by laser diffraction on Hicom’s Malvern 2000 Mastersizer
(with Hydro 2000MU) under the following conditions:
Mineral Type
CaCO3
Particle Refractive Index (Mie)
1.530
Particle Absorption Index (Mie)
0.1
Dispersant
Distilled Water
Dispersant RI
1.33
Pump speed
2000
Dispersion method (non-coated) Dry sample into 700 ml distilled water in beaker with 15 ml 0.5% w/v
Calgon T. 30s Ultrasonic Irradiation at Level 12 prior to measurement
Dispersion method (coated) Dry sample in test tube with 3 drops Nonidet P40, 15 ml 0.5% w/v Calgon
T, shake for 30s, soak for 1 hr. Froth killed with IPA, suspension agitated
with pipette and pipetted into 700 ml distilled water in beaker. 30s
Ultrasonic Irradiation at Level 12 prior to measurement.
4.3 Data analysis
Details of the procedures used for analysis of logged data are given in Appendix B.
H-2010.MIS.01 R0
16-September-2010
Page 7 of 28
CONFIDENTIAL
5 Test results & discussion
5.1 Feed material particle size distribution
The feed particle size distribution (PSD) measured on our Malvern laser size was close to the supplied
customer specification, as seen in Figure 1, although the top size may have been slightly coarser than
standard.
Parfill 7 (Hicom measurement)
Parfill 7 (Customer specification)
100
90
80
% Undersize
70
60
50
40
30
20
10
0
0.1
1
10
100
1000
Size (µm)
Figure 1
Nordkalk Parfill 7 feed size distribution compared with customer standard
Please note that there is often a wide discrepancy between Malvern (wet) sizing and Insitec (dry,
online) sizing data on the same product material. For the sake of consistency, unless noted
otherwise, all particle sizes mentioned in this report refer to the Malvern (wet) sizing data.
It is also important to recognise that virtually every size analysis method is likely to produce a
different result on the same sample. Therefore, the customer needs to analyse physical samples from
these pilot plant trials in order to correlate the data and information presented with their own
particular knowledge base.
5.2 Pilot plant results
Results from all tests are shown in Table 2, Table 3 and Table 4 below. The tabulated data is grouped
by product size and discussed below in terms of these groupings.
H-2010.MIS.01 R0
16-September-2010
Page 8 of 28
CONFIDENTIAL
Table 2
Summary of results for production of 3-4 µm material
Run Number
System Performance
Mill GE based on production rate, kWh/t
Feed F97, µm
Feed F80, µm
Feed F50, µm
Malvern (wet) product sizing data
Insitec online (dry) product sizing data
Recirculating load Ratio
Production rate, kg/h
Gross Power Draw, kW
Net Mill Power Draw, kW
Recirculating load, kg/h
ACX 200 Classifier Parameters
Classifier speed, rpm
System air flow, m3/h
Secondary air flow, m3/h
% Secondary Air
ACX200 Classifier Mass Balance
FEED, kg/h
PRODUCT, kg/h
RECYCLE, kg/h
System Configuration
Mill model
Mill speed, rpm
Discharge ports
Discharge slot width, mm
Liner material
Media
Media size, mm
Media S.G.
Mill Differential Pressure, mmWG
Mill Filling, J%
Additive
Additive rate vs fresh feed (%w/w)
Classifier Efficiency
Total Fines Mass Recovery
%Passing P97 in Classifier Feed
Classifier Efficiency @ P 97
Solids/Air Ratio to Classifier, kg/m3
H110 Plant Parameters
Feed rate, kg/h
Recycle rate, kg/h
Nominal Recirculating load Ratio
Classifier feed rate, kg/h
H-2010.MIS.01 R0
P97,
P90,
P80,
P50,
P97,
P90,
P80,
P50,
µm
µm
µm
µm
µm
µm
µm
µm
01A
02A
03A
12A
3/08/2010
12:20
150
73.8
51.8
17.5
3.07
2.52
2.15
1.55
3.48
2.54
1.91
0.96
30.0
29
6.65
4.35
870
3/08/2010
16:40
154
73.8
51.8
17.5
2.88
2.38
2.05
1.48
3.40
2.48
1.87
0.95
18.0
29
6.77
4.47
522
6/08/2010
11:25
169
73.8
51.8
17.5
3.42
2.84
2.44
1.77
4.23
3.16
2.44
1.19
15.0
24
6.34
4.04
360
13/09/2010
16:40
150
73.8
51.8
17.5
3.46
2.85
2.44
1.75
4.09
3.09
2.40
1.18
18.0
25
6.06
3.76
450
5283
800
265
33%
5283
800
267
33%
5283
800
274
34%
5285
800
271
34%
899
29
870
551
29
522
384
24
360
475
25
450
Hicom 25
760
Hicom 25
760
Hicom 25
760
Hicom 27
760
2/6
2/6
2/6
1.2
0.9
0.9
1/6*0.6; 1/6*0.9;
1/2*0.4
0.4, 0.6, 0.9
Steel
Ce-TPZ
2.4-2.8
6.0
93
52%
DEG
0.87
Steel
Ce-TPZ
1.4
6.0
125
52%
DEG
0.87
Steel
Ce-TPZ
1.4
6.0
126
52%
Stearic Acid
1.37
Steel
Ce-TPZ
1.4
6.0
137
52%
Stearic Acid
1.11
3.2%
35.8
8.7%
1.12
5.3%
35.9
14.2%
0.69
6.3%
41.3
14.7%
0.48
5.3%
41.9
12.2%
0.59
600
7400
12
8000
585
7415
13
8000
535
7465
14
8000
600
7400
12
8000
16-September-2010
Page 9 of 28
CONFIDENTIAL
Table 3
Summary of results for production of 5-6 µm material
Run Number
System Performance
Mill GE based on production rate, kWh/t
Feed F97, µm
Feed F80, µm
Feed F50, µm
Malvern (wet) product sizing data
Insitec online (dry) product sizing data
Recirculating load Ratio
Production rate, kg/h
Gross Power Draw, kW
Net Mill Power Draw, kW
Recirculating load, kg/h
ACX 200 Classifier Parameters
Classifier speed, rpm
System air flow, m3/h
Secondary air flow, m3/h
% Secondary Air
ACX200 Classifier Mass Balance
FEED, kg/h
PRODUCT, kg/h
RECYCLE, kg/h
System Configuration
Mill model
Mill speed, rpm
Discharge ports
Discharge slot width, mm
Liner material
Media
Media size, mm
Media S.G.
Mill Differential Pressure, mmWG
Mill Filling, J%
Additive
Additive rate vs fresh feed (%w/w)
Classifier Efficiency
Total Fines Mass Recovery
%Passing P97 in Classifier Feed
Classifier Efficiency @ P 97
Solids/Air Ratio to Classifier, kg/m3
H110 Plant Parameters
Feed rate, kg/h
Recycle rate, kg/h
Nominal Recirculating load Ratio
Classifier feed rate, kg/h
H-2010.MIS.01 R0
P97,
P90,
P80,
P50,
P97,
P90,
P80,
P50,
µm
µm
µm
µm
µm
µm
µm
µm
04A
05A
05B
06A
11A
6/08/2010
17:27
131
73.8
51.8
17.5
5.16
4.13
3.44
2.30
6.21
4.87
4.01
2.50
8.0
28
5.98
3.68
224
12/08/2010
15:25
138
73.8
51.8
17.5
4.79
3.87
3.26
2.21
6.05
4.53
3.61
1.98
9.0
29
6.31
4.01
261
12/08/2010
15:30
138
73.8
51.8
17.5
4.85
3.92
3.30
2.26
6.01
4.51
3.61
2.00
9.0
29
6.30
4.00
261
18/08/2010
14:05
113
73.8
51.8
17.5
4.97
4.00
3.36
2.28
6.25
4.78
3.83
2.22
7.6
31
5.81
3.51
236
2/09/2010
18:50
124
73.8
51.8
17.5
5.64
4.49
3.72
2.48
5.97
4.56
3.68
2.09
21.0
37
6.88
4.58
777
3740
800
277
35%
3682
801
278
35%
3682
800
278
35%
3758
797
277
35%
3627
800
285
36%
252
28
224
290
29
261
290
29
261
267
31
236
814
37
777
Hicom 25
760
Hicom 25
760
Hicom 25
760
Hicom 25
760
Hicom 26
760
2/6
1/6*0.6; 1/6*0.9
1/6*0.6; 1/6*0.9
1/6*0.6; 1/6*0.9
0.9
0.6, 0.9
0.6, 0.9
0.6, 0.9
1/6*0.6; 1/6*0.9;
1/2*0.4
0.4, 0.6, 0.9
Steel
Ce-TPZ
1.4
6.0
133
52%
Stearic Acid
1.27
Steel
Ce-TPZ
1.4
6.0
155
52%
Stearic Acid
1.23
Steel
Ce-TPZ
1.4
6.0
155
52%
Stearic Acid
1.23
Steel
Ce-TPZ
1.4
6.0
158
52%
Stearic Acid
1.15
Steel
Ce-TPZ
1.4
6.0
121
52%
Stearic Acid
0.96
11.1%
49.8
21.6%
0.32
10.0%
45.6
21.3%
0.36
10.0%
96.6
10.0%
0.36
11.6%
44.3
25.4%
0.33
4.5%
49.6
8.9%
1.02
760
6080
8
6840
725
6525
9
7250
725
6525
9
7250
885
6726
8
7611
730
7270
10
8000
16-September-2010
Page 10 of 28
CONFIDENTIAL
Table 4
Summary of results for production of 8-9 µm material
Run Number
System Performance
Mill GE based on production rate, kWh/t
Feed F97, µm
Feed F80, µm
Feed F50, µm
Malvern (wet) product sizing data
Insitec online (dry) product sizing data
Recirculating load Ratio
Production rate, kg/h
Gross Power Draw, kW
Net Mill Power Draw, kW
Recirculating load, kg/h
ACX 200 Classifier Parameters
Classifier speed, rpm
System air flow, m3/h
Secondary air flow, m3/h
% Secondary Air
ACX200 Classifier Mass Balance
FEED, kg/h
PRODUCT, kg/h
RECYCLE, kg/h
System Configuration
Mill model
Mill speed, rpm
Discharge ports
Discharge slot width, mm
Liner material
Media
Media size, mm
Media S.G.
Mill Differential Pressure, mmWG
Mill Filling, J%
Additive
Additive rate vs fresh feed (%w/w)
Classifier Efficiency
Total Fines Mass Recovery
%Passing P97 in Classifier Feed
Classifier Efficiency @ P 97
Solids/Air Ratio to Classifier, kg/m3
H110 Plant Parameters
Feed rate, kg/h
Recycle rate, kg/h
Nominal Recirculating load Ratio
Classifier feed rate, kg/h
H-2010.MIS.01 R0
P97,
P90,
P80,
P50,
P97,
P90,
P80,
P50,
µm
µm
µm
µm
µm
µm
µm
µm
07A
08A
09A
10A
31/08/2010
16:10
80
73.8
51.8
17.5
7.95
6.19
5.02
3.11
7.99
6.11
4.98
3.01
9.0
47
6.05
3.75
423
31/08/2010
18:00
76
73.8
51.8
17.5
9.25
6.98
5.57
3.40
7.95
6.12
5.02
3.09
11.2
53
6.35
4.05
594
2/09/2010
15:49
73
73.8
51.8
17.5
8.56
6.58
5.27
3.17
8.04
6.12
4.98
2.98
4.2
49
5.90
3.60
206
2/09/2010
17:25
77
73.8
51.8
17.5
8.53
6.61
5.32
3.24
8.47
6.35
5.09
3.05
11.0
56
6.59
4.29
616
2364
798
283
35%
2392
799
281
35%
2365
799
277
35%
2394
798
285
36%
470
47
423
647
53
594
255
49
206
672
56
616
Hicom 25
760
Hicom 25
760
Hicom 25
760
Hicom 25
760
1/6*0.6; 1/6*0.9;
1/2*0.4
0.4, 0.6, 0.9
1/6*0.6; 1/6*0.9;
1/2*0.4
0.4, 0.6, 0.9
1/6*0.6; 1/6*0.9;
1/2*0.4
0.4, 0.6, 0.9
1/6*0.6; 1/6*0.9;
1/2*0.4
0.4, 0.6, 0.9
Steel
Ce-TPZ
1.4
6.0
150
52%
Stearic Acid
0.76
Steel
Ce-TPZ
1.4
6.0
132
52%
Stearic Acid
0.72
Steel
Ce-TPZ
1.4
6.0
152
52%
Stearic Acid
0.99
Steel
Ce-TPZ
1.4
6.0
125
52%
Stearic Acid
0.87
10.0%
50.3
19.3%
0.59
8.2%
59.5
13.4%
0.81
19.2%
53.2
35.1%
0.32
8.3%
53.3
15.2%
0.84
1125
6875
6
8000
1180
6820
6
8000
1360
5712
4
7072
1175
6825
6
8000
16-September-2010
Page 11 of 28
CONFIDENTIAL
5.2.1
Product size 3-4 µm (P97) - Table 2
This series of test runs was conducted with the classifier rotor speed fixed at 5300 RPM (nominal).
While the ACX200 classifier is capable of higher speed (hence finer cut size), the speed used was a
conservative value that can be applied for scale up to the larger classifier sizes required for a
production plant.
The system air rate is obviously an important influence on classifier cut size also. Again, we adopted a
conservative approach of using a relatively high system air rate of 800 m3/h to ensure reliable
material transport in the grinding circuit. This air rate was used for all trials on Parfill 7.
In short, the product sizes obtained during these pilot plant trials can be readily achieved in a full
scale production plant using Hicom 110 kW mills with a commercially available classifier.
5.2.1.1 DEG only runs
Runs 1 and 2 were conducted with grinding aid only (diethylene glycol – DEG) to demonstrate the
system capability without stearic acid coating. This was of relevance as it is well known that in ball
mills for example, the grinding energy is greatly increased and hence production capacity is
decreased when attempting to grind and coat in the one machine.
While the grinding energy in both of these runs was similar, Run 2 conducted using 1.4 mm media
had a much lower circulating load compared to Run 1 conducted using 2.4-2.8 mm media. In
addition, the product size for Run 2 was slightly lower.
From this comparison we concluded that operation using the finer media was more efficient (as
expected) and all subsequent runs were conducted using the 1.4 mm media.
5.2.1.2 Stearic acid coating runs
In going to relatively high levels of stearic acid dosing in Runs 3 and 12, we see that the grinding
energy was similar to that obtained with DEG at the same classifier speed. However, the coated
product size is slightly higher.
The higher product size can be attributed to more effective dispersion of material in the classifier
separation zone. It is a known phenomenon of calcium carbonate air classification that as the
circulating load increases, the particle top cut decreases even though the classifier rotor speed and
system air rate remain unchanged. This phenomenon probably occurs because of a ‘filtering’ effect of
high solids loading in the swirling air in the separation zone just outside the classifier rotor.
The effect is quite clearly seen in Figure 2 which reproduces a chart from the Insitec online particle
size analyser. The red trace shows laser light transmission level which is inversely proportional to the
amount of material in the sampling pipe; higher transmission means lower solids loading.
The steady increase in product particle size (black traces) with increase in transmission (decrease in
solids loading) can clearly be seen in the chart.
H-2010.MIS.01 R0
16-September-2010
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CONFIDENTIAL
Figure 2
Example of changing product size with change in classifier solids loading
With stearic acid coating, the particles are more dispersed than with DEG alone, which is likely to
reduce the solids-loading filtering effect observed with non-coated material. This may partially
explain the coarser top cut with coated material at similar circulating loads, classifier speed and
system air rate, compared with non-coated material.
5.2.1.3 Product size distributions
The product size distributions shown in Figure 3 for the finest products made illustrate the difference
in classifier performance on coated and uncoated materials. The marked difference in distribution
shape as reported by the two measurement methods is also apparent.
NOR.P.A.001-2AP
Insitec (2A)
NOR.P.A.001-3AP
Insitec (3A)
100
90
80
% Undersize
70
60
50
40
30
20
10
0
0.1
1
10
Size (µm)
Figure 3
H-2010.MIS.01 R0
Product size distributions from the finest uncoated (Run 2) and coated (Run 3)
product samples
16-September-2010
Page 13 of 28
CONFIDENTIAL
5.2.2
Product size 5-6 µm (P97) - Table 3
For this series of tests, the Insitec size controller was set to a top cut (D97) of 6 µm nominal. The
classifier speed was allowed to vary under automatic control to maintain this cut size. An example of
such control can be seen in Figure 4.
D97 (Insitec)
D97 Set Point
4000
7
3900
6.8
3800
6.6
3700
6.4
3600
6.2
3500
6
3400
5.8
3300
5.6
3200
5.4
3100
5.2
3000
12/08 14:00
Figure 4
12/08 14:30
12/08 15:00
12/08 15:30
12/08 16:00
Size (µm)
Classifier Rotor Speed (RPM)
Classifier Speed
5
12/08 16:30
Example of product size control by automatic regulation of classifier speed
The product size distribution from Run 6 is shown in Figure 5. In general, the Malvern-measured
product size was somewhat lower and more variable than the Insitec-reported size, which is due to
the different measurement method and also possibly from variability in product sampling.
The data from Runs 4-6 is fairly consistent in terms of product rate. The lowest grinding energy and
smallest product size was obtained in Run 6.
In Run 11, the discharge open area on the grinding chamber was increased and the process was
‘pushed’ at a high circulating load. While this resulted in a significantly higher production rate, the
specific grinding energy was more or less the same as for Run 6.
This result demonstrates one way that production rate can be increased in the Hicom process.
H-2010.MIS.01 R0
16-September-2010
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CONFIDENTIAL
NOR.P.A.001-6AP
Insitec (P)
100
90
80
% Undersize
70
60
50
40
30
20
10
0
0.1
1
10
100
Size (µm)
Figure 5
5.2.3
PSD for intermediate coated product (Run 6)
Product size 8-9 µm (P97) - Table 4
For this series of tests, the product size controller was set to a D97 cut size (Insitec) of 8 µm. The
particle size distribution for Run 9 product is shown in Figure 6.
The data from Runs 7-10 showed a high degree of consistency in terms of specific grinding energy,
but with variation in production rate and power draw. This consistency indicates that the process
was probably quite well optimised for this product size under the range of conditions tested.
The best result was obtained with Run 9, which had the lowest grinding energy at a relatively low
circulating load rate.
5.2.4
Product size versus specific grinding energy
Figure 7 shows all of the P97 versus grinding energy test data. For the stearic acid coating runs, a line
drawn through the minimum grinding energy values represents the best performance obtained in the
pilot plant.
The DEG only data points are only slightly below this line. This clearly shows that there was only a
small reduction in process energy efficiency with simultaneous grinding and coating as compared to
grinding only using a typical glycol grinding aid.
This result is highly significant as it markedly differentiates the Hicom process from any other size
reduction method currently available for grinding and coating calcium carbonate.
H-2010.MIS.01 R0
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CONFIDENTIAL
NOR.P.A.001-9AP
Insitec (P)
100
90
80
% Undersize
70
60
50
40
30
20
10
0
0.1
1
10
100
Size (µm)
Figure 6
PSD for coarse coated product (Run 9)
DEG Only
Stearic acid coated
P97 Malvern (µm)
10
MINIMUM GRINDING ENERGY LINE
1
10
100
1000
Mill Specific Grinding Energy (kW.h/t)
Figure 7
H-2010.MIS.01 R0
Product size as a function of specific grinding energy – all data
16-September-2010
Page 16 of 28
CONFIDENTIAL
5.3 Scale-up and Hicom 110 production capacity
Experience has shown that full scale production capacity can usually be estimated from pilot plant
test results on the basis of mill specific grinding energy. This is because the grinding environment in
the Hicom 25 test mill is virtually identical to that in a Hicom 110 kW mill, provided the circulating
load is not too high.
The Hicom 110/60 mill has a nominal net power draw capability of 100 kW. Therefore estimates of
the corresponding capacity for a single Hicom 110/60 mill are obtained as follows:
Hicom 110 Mill Capacity (tph) = 100 (kW) / Pilot Plant Mill Grinding Energy (kWh/t)
In a number of the present test runs, the circulating load was relatively high due to the process being
‘pushed’ as much as possible to maximise production rate. However, in almost all such cases, a small
drop in fresh feed rate – no more than 10% – was sufficient to bring the circulating load down to a
low and stable level.
Experience has also shown that the total mill throughput (that is the circulating load, equal to fresh
feed plus recycle) should not exceed about 8000 kg/h in practice. Therefore, for those runs where
the projected full-scale circulating load calculated directly from the pilot plant recycle ratio exceeded
8000 kg/h, the classifier feed rate was capped at this value in the results tables shown above. The
projected Hicom mill capacity was also reduced by 10% for these runs. In other words, a value of
90 kW was used in the above formula rather than the full 100 kW.
The projected Hicom 110 kW mill capacity as a function of product size shown in Figure 8 below was
determined on the basis just described. The maximum capacity line shown corresponds to the
minimum energy line shown in Figure 7.
We have a high level of confidence that these production capacities would be achieved in practice.
5.4 Comments on production plant design
Overall, stable plant operation was obtained over the full range of conditions reported here. Similar
stable performance can be expected in a full scale production plant using Hicom 110 kW mills.
It is recognised that production capacity for a single Hicom 110 kW mill on the finest product may not
be economic. Therefore, we would propose a production plant concept using two Hicom 110 kW mill
operating in parallel but with a single classifier, system air blower and product collection filter. This
way, a doubling in mill capacity can be achieved with more or less the same capital outlay for
construction of the balance of the plant.
Details on a plant design utilising this two-mill concept are available on request.
H-2010.MIS.01 R0
16-September-2010
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CONFIDENTIAL
DEG only
Stearic Acid Coating
2000
Production Rate in H110 mill (kg/h)
1800
1600
MAXIMUM CAPACITY LINE
1400
1200
1000
800
600
400
200
0
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
P97 Malvern (µm)
Figure 8
H-2010.MIS.01 R0
Projected Hicom 110 kW production rate as a function of product size
16-September-2010
Page 18 of 28
CONFIDENTIAL
Appendix A – Hicom 25 Dry Pilot Plant: Generic Description and
Operating Procedures
IMPORTANT NOTE: The data presented in Appendices A and B is generic and may not correspond
to actual data obtained during the present test program.
Generic Description of the plant
The Hicom 25 dry pilot plant is shown in the picture below (Figure 9) and schematically in Figure 10.
The plant consists of a Hicom 25 kW mill with variable speed drive, operating in closed circuit with a
Comex ACX200 high efficiency air classifier. The entire plant is controlled and monitored using a
Siemens S7-300 PLC and Siemens WinCC SCADA package operating on a touch-panel PC mounted in
the main control cabinet.
Figure 9
Photograph showing the Hicom 25 dry pilot plant
A 75 mm screw feeder is used to transport material to the mill from a feed bin. Solids feed rate to
the mill is calculated from loss-in-weight measurement from a load cell on the feed hopper. The
calculated rate can be used in closed loop with the screw feeder VSD to provide feed rate control.
The Hicom 25 mill motor is controlled by a Siemens VSD in the main control cabinet. The mill is
generally operated at discrete speeds of 760 and 960 RPM corresponding to maximum chamber
acceleration of 30 and 50 G respectively. The mill drive lubrication system is monitored and
controlled by the central Siemens PLC.
H-2010.MIS.01 R0
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CONFIDENTIAL
FT FIC
PI
FI
VSD M
IA
PI
DUST
COLLECTOR
200 NB
INSITEC
15 0 N B
PI
COM MEX
ACX 200
CLASSIF IER
FI FT
PI
PI
M
VSD JT JI
SYSTEM
BLOWER 1
LOAD CELL
FI FT
FEED
HOPPER
SECONDARY AIR VALVE
PI
W
FINE PRODUCT
COLLECTION
VSD M
100 NB
FIC
100 NB
FI
JI JT VSD M
TS TI
PI PT
HICOM 25
MILL
PEBBLE TRAP
Figure 10
H-2010.MIS.01 R0
18-September-2010
PRIMARY AIR VALVE
Schematic diagram of the Hicom 25 dry pilot plant
Page 20 of 28
CONFIDENTIAL
The grinding circuit operates under vacuum in order to avoid dust emission. Material is drawn
through the mill and pneumatically conveyed to the classifier. The air flow required for effective
pneumatic transport through the mill is much less than that required for effective classification.
Therefore, additional air is drawn into the system through the primary air valve indicated on Figure
10.
The setting of this valve and the secondary air valve also control the differential pressure across the
mill – that is the mill vacuum.
Oversize particles, rejected by the classifier rotor, fall by gravity down the oversize chute for regrinding in the mill. The classifier is operated by a VSD which allows the rotor speed to be set to
achieve a precise product top cut size. Compressed air is used to seal both the classifier rotor and the
rotor bearings. The classifier oversize return is sealed by a 150 mm double-butterfly valve air lock
system as indicated on the diagram. The secondary air flow to the classifier is manually adjusted by a
butterfly valve, and monitored by an orifice-plate flow meter.
Air and fine product are pneumatically transported to a Torit-DCE DLM V20/12B Dalamatic dust
collector where the product is collected in a drum or bulker bag. The dust collector is sealed by a
200 mm double-butterfly valve air lock system.
An Insitec on-line particle size analyser is installed on the classifier fine-product line. This enables
instant feedback on classifier performance and provides the means for meeting precise particle size
specifications by automatic adjustment of classifier rotor speed.
Two blowers operated in parallel are used to generate the system air flow. A Rietschle SAP1500
(System Blower 2) is run at full speed, and a GAST R93150A (System Blower 1) is operated by a VSD
to provide trim control on system air flowrate in closed-loop feedback with an orifice-plate flow
meter downstream of the dust collector. The total system air capability is roughly 1600 m3/hr at 20 kPa using both blowers.
Instrumentation is incorporated for monitoring critical process and mill control parameters, most of
which are recorded on the SCADA system. The mill power draw is determined from direct reading of
the Mill VSD.
A microwave mass-flow indicator installed on the classifier feed (mill discharge) line provides
feedback as to whether the plant is at steady state.
The grinding chamber nominal volume is 10.7 L and its 40 mm discharge ports are positioned at the
circle of maximum diameter. Grates are placed over the discharge ports to retain the media inside
the grinding chamber. The grate slot width is generally selected at least one-half the diameter of the
smallest media particle used.
Stearic acid dosing system
The stearic acid dosing system for particle coating is shown in Figure 11 and Figure 12 below. Stearic
acid flakes (Symex #4989, Symex Holdings, Melbourne) are melted in the heated reservoir shown,
which is maintained at 70-80oC. The heated liquid stearic acid is then dosed directly (drip-wise) into
the feed tube of the Hicom mill through a heat-traced stainless steel tube using a Zenith gear pump
with DC speed control, which is also heat-traced. The gear pump enables precise, controlled and
reproducible dosing over a linear dosing rate calibration range of 4-20 g/min.
H-2010.MIS.01 R0
18-September-2010
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CONFIDENTIAL
As there is also fresh feed rate control on the plant, the stearic acid dosing can be manually ratioed
to that as required.
Figure 11
Hicom pilot plant stearic acid dosing system – reservoir and gear pump
Figure 12
Hicom pilot plant stearic acid dosing system – controls and dosing line
H-2010.MIS.01 R0
18-September-2010
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CONFIDENTIAL
Typical test procedure
After every chamber change-out, or after an extended shutdown, the mill is operated for twenty
minutes with an empty chamber to establish the no-load power. The required charge of media is
added to the mill before commencing each test series. The solids feed rate to the mill is selected, and
the system and secondary air flows set to maintain appropriate classifier conditions. The classifier
rotor speed is then adjusted to give the desired cut size based on Insitec particle size readings.
Product and recycle samples are taken once relatively steady-state plant operation is obtained, as
indicated by the mill discharge mass flow indicator. This is generally 30 to 45 minutes after starting a
run. Critical mill control and process parameters are monitored during each run and recorded on a
standard log sheet every time a sample is taken.
The recirculating load rate is estimated after taking a physical sample of the mill discharge after a
crash stop of the plant. The particle size distributions of the classifier feed, fine product and coarse
reject streams can be used to back-calculate the recirculating load ratio.
The rate of product discharge from the dust collector is calculated from gain-in-weight measurement
of the product bulk bag, which is positioned on electronic weigh-scales.
This rate is compared with the feed rate to assess whether the circuit is at steady state. Generally,
the feed and measured product rates must be within 20% of one another, otherwise the data is from
the run is not considered for analysis. The exception to this rule is when the material is very fine or
sticky and there is significant holdup of material in the dust collector. Under such conditions,
accurate determination of product rate is not possible over a short time period, and we rely on
microwave sensor readings of the circulating load to determine if the plant is at steady state.
The mill net power draw for calculation of specific mill grinding energy is determined as the
difference between the measured gross power and the no-load power.
Grinding circuit behaviour and sampling
Typical circuit responses for dry pilot plant operation and the test protocol followed are best
illustrated with reference to Figure 13 below, which shows a characteristic SCADA trend obtained
during a pilot plant trial.
In the example shown in Figure 13 , between 5:54 pm and 6:10 pm, the mill power draw (red trace)
was around 11 kW, the circulating load (black trace) was below 10% and the mill exit temperature
(light blue trace) was around 72oC.
The feed rate (oscillating blue trace) was increased slightly at around 6:10 pm. This resulted in an
increase in circulating load, a decrease in mill power and a decrease in mill temperature due to the
increased rate of heat removal from the mill from the higher solids throughput.
Despite the increased circulating load, the circuit is nevertheless stable as the circulating load is not
increasing above 15-20% on average.
This indicated level of circulating load was considered the maximum stable level for plant operation
in this particular case. Experience showed that further increases in feed rate resulted in accelerating
increase in circulating load rate due to the fact that the rate of fresh feed to the mill started to
exceed the rate of fine particle production.
H-2010.MIS.01 R0
18-September-2010
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CONFIDENTIAL
Figure 13
Hicom 25 pilot plant SCADA Trend screen
The objective in pilot plant trials was to adjust conditions such as discharge port open area, mill
vacuum, media size and quantity and other factors to try and maximize the mill feed rate before an
excessive circulating load rate was reached.
In the example shown in Figure 13, at around 6:36 pm, the plant was stopped (crash stop) by
stopping the mill, air blowers, the classifier and by shutting the classifier return air lock valves. This
way, a ‘snap shot’ was taken of the circuit from which samples could be taken for analysis. We
sampled the recycle stream, the residual powder on the internal walls of the mill body (equivalent to
classifier feed) and also the fine product collected in the product filter. These samples were used to
estimate recirculating load ratio, as outlined in Appendix B.
For some runs, the mill contents may also be removed and the powder and grinding media separated
by screening. This way it is possible to determine the holdup level of powder in the mill and also to
assess media wear.
H-2010.MIS.01 R0
18-September-2010
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CONFIDENTIAL
Appendix B – Data Analysis Procedures
IMPORTANT NOTE: The data presented in Appendices A and B is generic and may not correspond
to actual data obtained during the present test program.
Test conditions
All of the data logged on the SCADA system was collated into Excel spreadsheets. Where necessary, a
simple first order filter was applied to smooth the data for more accurate estimation of parameter
values at the time of sample collection or crash stop.
The resulting values are shown in the test condition tables in the body of this report.
Feed and product rate
For most test runs, estimation of feed and product rate was done by calculating the numerical
derivative of the recorded change in weight of the feed hopper and the product weigh scales
respectively. First-order filtering before and after numerical differentiation was used to reduce the
affect of inherent ‘noise’ in the data.
Typical rate calculation results are illustrated in Figure 14 below.
Figure 15 shows the corresponding process parameters of mill air temperature (discharge
temperature), mill power and circulating load corresponding to the same time period of the data in
Figure 13 and Figure 14. It can be seen that a relatively small increase in average feed rate from
around 58 kg/h to around 62 kg/h resulted in a significant increase in circuit load and it was
concluded that further increase was not possible beyond around 62 kg/h for this particular mill and
plant configuration.
Circulating load ratio estimation
The circulating load ratio, hence coarse recycle rate, was estimated from the particle size distribution
of samples of classifier feed, fine product and coarse reject. The Excel solver function was used to
minimize the sum of squares of the difference between measured particles size distribution and the
corresponding particle size distribution calculated using an assumed ratio and the other two
distributions. Generally, the measured classifier feed was considered the least accurate of the
collected samples and this was usually taken as the basis for the estimation procedure.
In the example shown in Figure 16 below, it can be seen the calculated and measured classifier feed
distribution closely match, which gives a high level of confidence in the ratio of 6.6 calculated for this
particular test run.
Calculation of the ratio using the coarse return and the fine product was also done to verify accuracy
of the primary estimate. In most cases, variation in calculated values was less than 10%.
The coarse recycle rate was then obtained by multiplying the steady state feed rate by the estimated
recirculating load ratio.
For those trial runs where no crash-stop samples were collected, the ratio was estimated from the
recirculating load level indicated on the microwave sensor output. These estimates were considered
accurate only within 20%.
H-2010.MIS.01 R0
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CONFIDENTIAL
Calculated Feed rate (filtered)
Feed rate (PLC output)
Feed Hopper Weight (raw)
Feed Hopper Weight (filtered)
100
620.0
90
600.0
80
70
580.0
50
560.0
WT (kg)
RATE (kg/h)
60
40
540.0
30
20
520.0
10
0
500.0
19/03/2010 16:00
Figure 14
19/03/2010 17:00
19/03/2010 18:00
Hicom 25 pilot plant feed rate estimation example
Air Temp
Mill Power
Circulating Load
80.0
70.0
60.0
50.0
40.0
30.0
20.0
10.0
0.0
19/03/2010 16:00
Figure 15
19/03/2010 17:00
19/03/2010 18:00
Process parameters corresponding to the time periods shown in Figure 13 and Figure
14
H-2010.MIS.01 R0
18-September-2010
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CONFIDENTIAL
Measured classifier f eed
Measured coarse reject
Calculated Classifier Feed
Measured f ine product
100
90
80
% Undersize
70
60
50
40
30
20
10
0
0.1
1
10
100
Size (µm)
Figure 16 Results from estimation of recirculation load ratio (RLR) using sum of squares error (SSE)
minimization on adjustment of the calculated classifier feed particle size distribution
H-2010.MIS.01 R0
18-September-2010
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CONFIDENTIAL
DISCLAIMER
1.
In conducting equipment testing, careful regard is given to the customer’s requirements. However, operating conditions and
materials used in testing cannot be guaranteed to replicate all operating materials or conditions in actual industrial use.
2.
The results shown in this test report may differ with different materials or in different environmental or operating conditions. Hicom
is not liable to you or any other person in relation to any failure to duplicate the results in this test report.
3.
Hicom warrants only that:
•
It has taken reasonable care in the conduct of tests and the preparation of this report; and
•
The test results in this report reflect the test results achieved.
4.
Hicom does not make, and will not be liable for any other representations or warranties, expressed or implied.
5.
This report is provided subject to confidentiality, only for the information of the party to whom it is addressed and solely for the
purpose of that party assessing Hicom’s equipment. Hicom accepts no responsibility for any reliance placed on this report by any
other party.
H-2010.MIS.01 R0
18-September-2010
Page 28 of 28
Bilaga 5
Hicom Technologies Pty Ltd
Head Office: 67 Randle Road, Pinkenba QLD 4008 Australia Tel: +61 7 3121 2900 Fax: +61 7 3121 2901 Confidential Report H‐2011.MIS.02 Hicom pilot plant dry grinding trials on Calcium Carbonate for Misec AB: OMYACARB 10 results CONFIDENTIAL Contents 1 Introduction ..................................................................................................................................... 3 2 Test results & discussion ................................................................................................................. 3 2.1 Feed material particle size distribution ................................................................................... 3 2.2 Pilot plant results ..................................................................................................................... 3 2.3 Product size versus specific grinding energy ........................................................................... 7 2.3.1 2.4 Comparison with Nordkalk data ...................................................................................... 7 Hicom 110 production capacity............................................................................................... 8 Figures Figure 1 OMYACARB 10 feed size distribution compared with Nordkalk Parfill 7 .............................. 3 Figure 2 Product size as a function of specific grinding energy – all data ........................................... 7 Figure 3 P97 versus grinding energy: present data compared with Nordkalk results ......................... 8 Figure 4 Projected Hicom 110 kW production rate as a function of product size .............................. 9 Tables Table 1 OMYACARB‐10 trials – summary of test conditions and results (1) ....................................... 4 Table 2 OMYACARB‐10 trials – summary of test conditions and results (2) ....................................... 5 Table 3 OMYACARB‐10 trials – summary of test conditions and results (3) ....................................... 6 Author: Dr. Steve Marshall Report Date: 25th January 2011 Revision No: 0 Comments: Initial release for review by customer H‐2011.MIS.02 R0.docx 25‐January‐2011 Page 2 of 10 CONFIDENTIAL 1 Introduction This report presents results from a second series of trials on simultaneous grinding and coating of calcium carbonate undertaken for Misec AB. The test material was a typical limestone sourced from OMYA Australia, chosen with the aim of providing OMYA‐SE with samples of coated product for evaluation in Sweden. Details of the background to this test program and also of the Hicom pilot plant and data analysis procedures are provided in the first report to Misec AB (Hicom No. H‐2010.MIS.01 R1). The focus here is on summarizing the results and comparing them with those obtained from testing of Nordkalk feed material. 2 Test results & discussion 2.1 Feed material particle size distribution Figure 1 shows that the OMYACARB‐10 feed material was slightly finer than the Parfill 7 used for the first series of trials, but otherwise typical of a ball‐milled product. OMYACARB-10
NORDKALK PARFILL 7
100
90
80
% Undersize
70
60
50
40
30
20
10
0
0.1
1
10
100
Particle Size (µm)
Figure 1 OMYACARB 10 feed size distribution compared with Nordkalk Parfill 7 2.2 Pilot plant results Test conditions and results from all pilot plant runs are shown in Table 1, Table 2 and Table 3 below. H‐2011.MIS.02 R0.docx 25‐January‐2011 Page 3 of 10 CONFIDENTIAL Table 1 OMYACARB‐10 trials – summary of test conditions and results (1) Run Number
System Performance
Mill GE based on production rate, kWh/t
Feed F97, µm
Feed F80, µm
Feed F50, µm
Malvern (wet) product sizing data
Insitec online (dry) product sizing data
Recirculating load Ratio
Production rate, kg/h
Gross Power Draw, kW
Net Mill Power Draw, kW
Recirculating load, kg/h
ACX 200 Classifier Parameters
Classifier speed, rpm
System air flow, m3/h
Secondary air flow, m3/h
% Secondary Air
ACX200 Classifier Mass Balance
FEED, kg/h
PRODUCT, kg/h
RECYCLE, kg/h
System Configuration
Mill speed, rpm
Liner material
Media
Media size, mm
Media S.G.
Mill Differential Pressure, mmWG
Mill Filling, J%
Additive
Additive rate vs fresh feed (%w/w)
Classifier Efficiency
Total Fines Mass Recovery
%Passing P97 in Classifier Feed
Classifier Efficiency @ P97
Solids/Air Ratio to Classifier, kg/m3
H110 Plant Parameters
Feed rate, kg/h
Recycle rate, kg/h
Nominal Recirculating load Ratio
Classifier feed rate, kg/h
H‐2011.MIS.02 R0.docx P97,
P90,
P80,
P50,
P97,
P90,
P80,
P50,
µm
µm
µm
µm
µm
µm
µm
µm
01A
02A
03A
04A
05A
05B
06A
06B
07A
07B
18/11/2010
16:30
164
43.0
30.7
11.1
2.81
2.31
1.99
1.44
3.07
2.24
1.66
0.89
3.5
25
6.45
4.15
89
18/11/2010
17:45
168
43.0
30.7
11.1
2.60
2.16
1.87
1.36
3.10
2.27
1.69
0.89
7.7
26
6.68
4.38
201
27/11/2010
8:53
181
43.0
30.7
11.1
2.66
2.20
1.89
1.35
3.15
2.29
1.71
0.90
6.8
27
7.25
4.95
187
27/11/2010
11:25
193
43.0
30.7
11.1
3.28
2.72
2.35
1.70
4.20
3.16
2.45
1.20
9.8
20
6.14
3.84
194
29/11/2010
14:58
185
43.0
30.7
11.1
3.33
2.76
2.37
1.71
4.08
3.04
2.33
1.14
6.5
20
6.02
3.72
131
29/11/2010
15:30
186
43.0
30.7
11.1
3.34
2.77
2.39
1.73
4.11
3.06
2.35
1.15
9.1
21
6.18
3.88
190
29/11/2010
16:18
192
43.0
30.7
11.1
3.46
2.84
2.42
1.72
4.10
3.06
2.35
1.15
13.5
22
6.44
4.14
290
29/11/2010
16:53
180
43.0
30.7
11.1
3.60
2.95
2.51
1.78
4.10
3.07
2.36
1.16
8.8
22
6.25
3.95
193
29/11/2010
17:30
199
43.0
30.7
11.1
3.32
2.75
2.37
1.72
4.03
3.02
2.31
1.14
18.2
23
6.80
4.50
411
29/11/2010
17:55
188
43.0
30.7
11.1
3.32
2.75
2.37
1.72
4.21
3.08
2.34
1.14
18.2
23
6.63
4.33
421
5283
799
247
31%
5283
800
250
31%
5283
800
267
33%
5285
801
262
33%
5285
799
248
31%
5285
799
250
31%
5285
800
254
32%
5285
800
252
32%
5285
799
256
32%
5284
799
259
32%
114
25
89
227
26
201
215
27
187
214
20
194
151
20
131
211
21
190
311
22
290
215
22
193
434
23
411
444
23
421
760
Steel
Ce-TPZ
1.4
6.0
175
52%
DEG
1.00
760
Steel
Ce-TPZ
1.4
6.0
170
52%
DEG
0.97
760
Steel
Ce-TPZ
1.4
6.0
147
52%
DEG
1.38
760
Steel
Ce-TPZ
1.4
6.0
195
52%
Stearic Acid
0.87
760
Steel
Ce-TPZ
1.4
6.0
181
52%
Stearic Acid
1.12
760
Steel
Ce-TPZ
1.4
6.0
177
52%
Stearic Acid
1.08
760
Steel
Ce-TPZ
1.4
6.0
167
52%
Stearic Acid
1.29
760
Steel
Ce-TPZ
1.4
6.0
169
52%
Stearic Acid
1.26
760
Steel
Ce-TPZ
1.4
6.0
159
52%
Stearic Acid
1.34
760
Steel
Ce-TPZ
1.4
6.0
145
52%
Stearic Acid
1.32
22.2%
49.5
43.5%
0.14
11.5%
41.2
27.1%
0.28
12.8%
42.7
29.0%
0.27
9.3%
47.8
18.9%
0.27
13.3%
45.5
28.3%
0.19
9.9%
43.9
21.8%
0.26
6.9%
42.7
15.7%
0.39
10.2%
46.4
21.3%
0.27
5.2%
41.4
12.2%
0.54
5.2%
42.1
12.0%
0.56
610
2136
4
2746
595
4577
8
5172
555
3791
7
4346
520
5074
10
5594
540
3518
7
4058
540
4923
9
5463
520
7003
13
7523
555
4890
9
5445
455
7545
17
8000
480
7520
16
8000
25‐January‐2011 Page 4 of 10 CONFIDENTIAL Table 2 OMYACARB‐10 trials – summary of test conditions and results (2) Run Number
System Performance
Mill GE based on production rate, kWh/t
Feed F97, µm
Feed F80, µm
Feed F50, µm
Malvern (wet) product sizing data
Insitec online (dry) product sizing data
Recirculating load Ratio
Production rate, kg/h
Gross Power Draw, kW
Net Mill Power Draw, kW
Recirculating load, kg/h
ACX 200 Classifier Parameters
Classifier speed, rpm
System air flow, m3/h
Secondary air flow, m3/h
% Secondary Air
ACX200 Classifier Mass Balance
FEED, kg/h
PRODUCT, kg/h
RECYCLE, kg/h
System Configuration
Mill speed, rpm
Liner material
Media
Media size, mm
Media S.G.
Mill Differential Pressure, mmWG
Mill Filling, J%
Additive
Additive rate vs fresh feed (%w/w)
Classifier Efficiency
Total Fines Mass Recovery
%Passing P97 in Classifier Feed
Classifier Efficiency @ P97
Solids/Air Ratio to Classifier, kg/m3
H110 Plant Parameters
Feed rate, kg/h
Recycle rate, kg/h
Nominal Recirculating load Ratio
Classifier feed rate, kg/h
H‐2011.MIS.02 R0.docx P97,
P90,
P80,
P50,
P97,
P90,
P80,
P50,
µm
µm
µm
µm
µm
µm
µm
µm
08A
09A
10A
10B
11A
11B
12A
13A
14A
15A
1/12/2010
9:20
194
43.0
30.7
11.1
3.25
2.70
2.32
1.68
4.07
3.03
2.32
1.13
15.3
23
6.70
4.40
348
1/12/2010
10:16
189
43.0
30.7
11.1
3.28
2.72
2.34
1.70
4.13
3.08
2.36
1.15
16.7
23
6.73
4.43
392
1/12/2010
11:30
178
43.0
30.7
11.1
3.21
2.66
2.28
1.65
4.02
3.00
2.29
1.12
18.0
26
6.85
4.55
461
1/12/2010
12:00
191
43.0
30.7
11.1
3.21
2.66
2.29
1.65
3.97
2.96
2.26
1.11
20.2
26
7.21
4.91
520
1/12/2010
15:45
146
43.0
30.7
11.1
4.14
3.35
2.83
1.94
5.98
4.04
3.01
1.44
11.5
30
6.62
4.32
339
1/12/2010
16:08
146
43.0
30.7
11.1
4.17
3.38
2.85
1.98
5.99
4.04
3.01
1.44
12.4
30
6.64
4.34
370
1/12/2010
16:57
148
43.0
30.7
11.1
4.25
3.44
2.90
2.01
6.00
4.06
3.03
1.45
15.8
32
7.02
4.72
503
1/12/2010
17:45
145
43.0
30.7
11.1
4.24
3.43
2.89
1.99
5.98
4.05
3.02
1.45
15.6
34
7.20
4.90
526
2/12/2010
10:40
139
43.0
30.7
11.1
4.30
3.47
2.92
2.00
5.95
4.12
3.10
1.52
13.1
34
7.02
4.72
443
2/12/2010
12:47
141
43.0
30.7
11.1
4.46
3.61
3.05
2.11
6.13
4.20
3.15
1.53
16.3
42
8.22
5.92
682
5284
801
260
32%
5284
799
262
33%
5284
799
271
34%
5283
800
279
35%
4256
801
260
32%
4245
800
260
33%
4189
801
264
33%
4119
800
267
33%
3995
801
260
32%
3851
801
269
34%
370
23
348
415
23
392
486
26
461
545
26
520
369
30
339
399
30
370
535
32
503
559
34
526
477
34
443
724
42
682
760
Steel
Ce-TPZ
1.4
6.0
160
52%
Stearic Acid
1.34
760
Steel
Ce-TPZ
1.4
6.0
154
52%
Stearic Acid
1.02
760
Steel
Ce-TPZ
1.4
6.0
168
52%
Stearic Acid
1.29
760
Steel
Ce-TPZ
1.4
6.0
157
52%
Stearic Acid
1.28
760
Steel
Ce-TPZ
1.4
6.0
163
52%
Stearic Acid
1.03
760
Steel
Ce-TPZ
1.4
6.0
160
52%
Stearic Acid
1.02
760
Steel
Ce-TPZ
1.4
6.0
155
52%
Stearic Acid
1.04
760
Steel
Ce-TPZ
1.4
6.0
156
52%
Stearic Acid
1.06
760
Steel
Ce-TPZ
1.4
6.0
168
52%
Stearic Acid
1.05
760
Steel
Ce-TPZ
1.4
6.0
161
52%
Stearic Acid
1.04
6.1%
41.5
14.3%
0.46
5.6%
43.2
12.7%
0.52
5.3%
41.5
12.3%
0.61
4.7%
41.6
11.0%
0.68
8.0%
45.6
17.1%
0.46
7.4%
45.6
15.8%
0.50
6.0%
45.5
12.7%
0.67
6.0%
45.3
12.9%
0.70
7.1%
44.4
15.5%
0.59
5.8%
46.0
12.2%
0.90
465
7535
16
8000
475
7525
16
8000
505
7495
15
8000
475
7525
16
8000
615
7385
12
8000
615
7385
12
8000
610
7390
12
8000
620
7380
12
8000
650
7350
11
8000
640
7360
12
8000
25‐January‐2011 Page 5 of 10 CONFIDENTIAL Table 3 OMYACARB‐10 trials – summary of test conditions and results (3) Run Number
System Performance
Mill GE based on production rate, kWh/t
Feed F97, µm
Feed F80, µm
Feed F50, µm
Malvern (wet) product sizing data
Insitec online (dry) product sizing data
Recirculating load Ratio
Production rate, kg/h
Gross Power Draw, kW
Net Mill Power Draw, kW
Recirculating load, kg/h
ACX 200 Classifier Parameters
Classifier speed, rpm
System air flow, m3/h
Secondary air flow, m3/h
% Secondary Air
ACX200 Classifier Mass Balance
FEED, kg/h
PRODUCT, kg/h
RECYCLE, kg/h
System Configuration
Mill speed, rpm
Liner material
Media
Media size, mm
Media S.G.
Mill Differential Pressure, mmWG
Mill Filling, J%
Additive
Additive rate vs fresh feed (%w/w)
Classifier Efficiency
Total Fines Mass Recovery
%Passing P97 in Classifier Feed
Classifier Efficiency @ P97
Solids/Air Ratio to Classifier, kg/m3
H110 Plant Parameters
Feed rate, kg/h
Recycle rate, kg/h
Nominal Recirculating load Ratio
Classifier feed rate, kg/h
H‐2011.MIS.02 R0.docx P97,
P90,
P80,
P50,
P97,
P90,
P80,
P50,
µm
µm
µm
µm
µm
µm
µm
µm
16A
16B
17A
17B
18A
18B
19A
20A
2/12/2010
14:05
86
43.0
30.7
11.1
6.75
5.20
4.22
2.66
8.12
5.78
4.47
2.50
7.9
59
7.41
5.11
471
2/12/2010
14:40
84
43.0
30.7
11.1
6.66
5.11
4.15
2.63
7.94
5.65
4.37
2.42
7.7
60
7.33
5.03
461
2/12/2010
15:25
85
43.0
30.7
11.1
7.01
5.41
4.40
2.78
8.03
5.63
4.33
2.36
8.1
69
8.23
5.93
559
2/12/2010
15:40
86
43.0
30.7
11.1
6.94
5.37
4.36
2.76
7.96
5.63
4.35
2.38
8.5
70
8.37
6.07
599
2/12/2010
16:26
63
43.0
30.7
11.1
10.10
7.30
5.72
3.36
10.60
7.25
5.51
3.01
6.2
79
7.27
4.97
492
2/12/2010
16:45
63
43.0
30.7
11.1
10.48
7.52
5.90
3.50
10.70
7.29
5.52
3.00
6.0
79
7.30
5.00
479
3/12/2010
11:15
67
43.0
30.7
11.1
9.75
7.41
5.90
3.53
10.60
7.28
5.54
3.00
5.1
77
7.49
5.19
394
3/12/2010
12:04
74
43.0
30.7
11.1
8.88
6.76
5.40
3.28
9.56
6.62
5.03
2.73
6.1
79
8.12
5.82
481
2668
800
272
34%
2675
799
270
34%
2670
800
273
34%
2640
799
272
34%
2225
801
268
33%
2241
800
267
33%
2190
799
266
33%
2387
800
269
34%
530
59
471
520
60
461
628
69
559
669
70
599
570
79
492
558
79
479
471
77
394
560
79
481
760
Steel
Ce-TPZ
1.4
6.0
171
52%
Stearic Acid
1.08
760
Steel
Ce-TPZ
1.4
6.0
173
52%
Stearic Acid
1.08
760
Steel
Ce-TPZ
1.4
6.0
172
52%
Stearic Acid
1.04
760
Steel
Ce-TPZ
1.4
6.0
171
52%
Stearic Acid
1.03
760
Steel
Ce-TPZ
1.4
6.0
172
52%
Stearic Acid
1.05
760
Steel
Ce-TPZ
1.4
6.0
173
52%
Stearic Acid
1.04
760
Steel
Ce-TPZ
1.4
6.0
181
52%
Stearic Acid
0.84
760
Steel
Ce-TPZ
1.4
6.0
179
52%
Stearic Acid
0.82
11.2%
49.5
21.9%
0.66
11.4%
48.7
22.8%
0.65
11.0%
52.4
20.4%
0.78
10.5%
51.7
19.7%
0.84
13.8%
65.0
20.6%
0.71
14.2%
66.1
20.8%
0.70
16.4%
62.4
25.5%
0.59
14.1%
61.9
22.1%
0.70
1045
6955
7
8000
1065
6935
7
8000
1055
6945
7
8000
1045
6955
7
8000
1425
6575
5
8000
1425
6575
5
8000
1335
6665
5
8000
1225
6775
6
8000
25‐January‐2011 Page 6 of 10 CONFIDENTIAL Differences between Malvern and Insitec (dry, on‐line) particles size analyses were similar to those reported previously. Only Malvern data is discussed here. It can be seen a reasonably wide range of product sizes was canvassed in this test series. In addition, different coating levels for stearic acid were evaluated to provide samples for evaluation. In general, there was little evidence that variations in coating level between 0.8% and 1.3% had any effect on plant performance or production capacity. 2.3 Product size versus specific grinding energy All of the P97 versus grinding energy test data is shown in Figure 2. Most of the data lies on the same straight line indicating the plant was operated at close to optimum conditions for most of the trials. This was not unexpected as the process was pre‐optimised on the Nordkalk Parfill 7 material. Coated
Grinding Aid Only (DEG)
P97 - Malvern Sizing (µm)
10
1
10
100
1000
Specific Grinding Energy (kWh/t)
Figure 2 Product size as a function of specific grinding energy – all data The reduction in grinding energy obtained when using grinding aid only is also similar to that observed with the Nordkalk test series. Indeed, general experience with calcium carbonate processing in the Hicom mill is that grinding energy is increased by 20‐30% when simultaneous grinding and coating, as compared to optimized processing with grinding aid only. 2.3.1
Comparison with Nordkalk data The comparison shown Figure 2Figure 3 indicates the OMYACARB‐10 and Nordkalk Parfill materials exhibit very similar grindability in the Hicom mill. It might be argued that the Nordkalk material was H‐2011.MIS.02 R0.docx 25‐January‐2011 Page 7 of 10 CONFIDENTIAL slightly more refractory at the fine end of the spectrum studied – say below five µm – but the differences are fairly marginal. OMYACARB-10 DATA
NORDKALK DATA
P97 - Malvern Sizing (µm)
10
1
50
500
Specific Grinding Energy (kWh/t)
Figure 3 P97 versus grinding energy: present data compared with Nordkalk results 2.4 Hicom 110 production capacity The production rate estimates shown in Figure 4 are consistent with those previously reported for the Nordkalk trials. Given the consistency of the present data set, and the similarity in grindability between the respective test materials, the straight line correlation shown Figure 4 is probably the more reliable predictor of expected Hicom 110 kW mill performance on simultaneous grinding and coating of a ‘typical’ calcium carbonate. The ca. 25% difference in mill productivity between coated and grinding aid only operation is also evident in Figure 4, reflecting the differences in specific grinding energy mentioned earlier. Finally, it is hoped the data presented here and in the previous report, together with samples of coated materials provided to respective parties, will provide sufficient information for economic assessment of the use of Hicom mills in this application. H‐2011.MIS.02 R0.docx 25‐January‐2011 Page 8 of 10 CONFIDENTIAL Coated
Grinding Aid only
1600
Estimated H110 Mill Capacity (kg/h)
1400
1200
1000
800
600
400
200
0
0
2
4
6
8
10
12
P97 - Malvern Sizing (µm)
Figure 4 Estimated Hicom 110 kW mill production rate as a function of product size H‐2011.MIS.02 R0.docx 25‐January‐2011 Page 9 of 10 CONFIDENTIAL DISCLAIMER 1.
In conducting equipment testing, careful regard is given to the customer’s requirements. However, operating conditions and materials used in testing cannot be guaranteed to replicate all operating materials or conditions in actual industrial use. 2.
The results shown in this test report may differ with different materials or in different environmental or operating conditions. Hicom is not liable to you or any other person in relation to any failure to duplicate the results in this test report. 3.
Hicom warrants only that: •
It has taken reasonable care in the conduct of tests and the preparation of this report; and •
The test results in this report reflect the test results achieved. 4.
Hicom does not make, and will not be liable for any other representations or warranties, expressed or implied. 5.
This report is provided subject to confidentiality, only for the information of the party to whom it is addressed and solely for the purpose of that party assessing Hicom’s equipment. Hicom accepts no responsibility for any reliance placed on this report by any other party. H‐2011.MIS.02 R0.docx 25‐January‐2011 Page 10 of 10