Zirconium Oxide in Metal Finishing

Transcription

Zirconium Oxide
in Metal Finishing
Bill Gaines
[email protected]
Zirconium Oxide in Metal Finishing
The Zr Process
Chemistry Introduced/Chemistry Removed
Zr Water Treatment
Zr Toxicity
Zr Regulations
Phosphate is part of a highly monitored, highly controlled painting process:
Pre-Cleaner
Stage
From body
shop
Cleaner
spray
Deluge
spray
Robot roof
ditch seal
station
Sealer
deck #0
Sealer
deck #1
Sealer
deck #2
Enamel
Oven
Enamel
strip
Cleaner
dip
E-coat
strip
Sealer gel
oven
H20 rinse
dip
E-coat
oven
Activation
dip
DI spray &
virgin DI spray
Sealer gel
cooling
Enamel
Clearcoat booth
Seek & repair
( Low & High Platform )
E-coat
scuff
Enamel
Basecoat booth
Phosphate
dip
DI water
dip
Blow
-off
Blow - off
Wax &
Blackout booth
H20 rinse Passivation
dip
dip
U/F dip&
virgin
U/F spray
Prime
spray booth
Prime
scuff
Surge
Spot repair
U/F perm
spray
DI dip &
virgin
DI spray
E-coat dipcream coat
rinse
Prime Oven
Cooling tunnel
To trim
PHOSPHATE STAGES 1-7
Times:
Stage Description:
Zone Description:
:27
:27
:27
Stage 1
Spray Cleaner 1
Stage 2
Deluge
Spray Cleaner 2
Drain Zone
:37
1:47
20' 8"
20' 8"
20' 8"
28' 9"
Stage 3
:47
Stage 4
Immersion Cleaner
:27
:37
Stage 5
City Water Rinse
Drain Zone
1:47
:36
1:47
:47
Stage 6
Drain Zone
Stage 7
Drain Zone
Immersion Rinse Conditioner
Immersion Phosphate
Drain Zone
From Body Shop
Shown Compressed
Length in Feet:
Phosphate Conveyor Parameters
Job/Hour
Line Speed
Conveyor Type
Job Spacing
Total Vehicle Length
Job Pitch
Total Application Time
74.6
46.3 FPM
OH/P&F
11'5"
18'8" to 21'3"
11'5"
32 minutes
82' 10"
Spray Cleaner 1 - CK275
Product ID
Product ID 2
Product ID 3
Concentration %
Free Alkalinity
Total Alkalinity
Ph Range
Chemkleen 275
N/A
N/A
N/C
1 - 2.4
1.4
N/A
Tank Capacity (US Gallons)
3600 GAL
Total Dwell Time
30 secs
Temperature
Ambient
Overflow Rate
N/A
Counterflow Rate
N/A
Over to Drain Rate
N/A
Total Header Rings
N/A
Total Number of Nozzles
96
Total Flow
N/C
Total Number of Tank Eductors
N/A
Header Pressure for Eductors
N/A
N/A
Drain Zone Apex Location
Tank Turn-Overs per Hour
N/A
Circulation
Pump Type
Number of Pumps
Pump HP
Gallons Per Minute
Risers
Gusher
2
75
N/C
N/A
Chemical Feed Pump Types
1
Pulsatron
3
2
4
Quick Feed Pumps Present?
No
Deluge - City Water
Fill Make-Up
Total Alkalinity
Total Dwell Time
Temperature
Overflow Rate
Counterflow Rate
Over to Drain Rate
Total Header Rings
Total Flow
8 ft from end
N/A
Circulation
Gusher
2
30
N/C
N/A
Filtering
Filter Type
Microns:
Number of Filters:
# of Vessels:
Bags per Vessel:
Do you use Magnets:
Change Point:
Filtering
Filter Type
City Water
N/A
8,625
30 secs
Ambient
15 gpms
N/A
N/A
N/A
N/A
N/C
N/A
N/A
Pump Type
Number of Pumps
Pump HP
Gallons Per Minute
Risers
36' 4"
Bag filters
400
21
3
7
No
N/A
Product ID
Product ID 2
Product ID 3
Concentration %
Free Alkalinity
Total Alkalinity
Ph Range
Chemkleen 166HP
Chemkleen 171A
N/A
N/C
.5-1.1
N/A
N/A
16,385
Total Dwell Time
35 secs
Temperature
120 - 130
Overflow Rate
15 gpms
Counterflow Rate
N/A
Over to Drain Rate
N/A
Total Header Rings
15
198
Total Flow
N/C
N/A
N/A
10 Feet From End
N/A
Circulation
Pump Type
Number of Pumps
Pump HP
Gallons Per Minute
Risers
Gusher
3
40
N/C
N/C
1
N/A
3
2
4
Overhead Nozzles
No
Filtering
bag filter
# of Nozzles
N/A
Microns:
400
Nozzle Type
N/A
Microns:
200
Number of Filters:
# of Vessels:
Bags per Vessel:
Do you use Magnets:
Change Point:
12
2
6
no
Pressure
Flow Rate
N/A
N/A
Number of Filters:
# of Vessels:
Bags per Vessel:
Do you use Magnets:
Change Point:
30
3
10
No
Pressure
Heat Exchanger
Type
Inlet Pressure
Outlet Pressure
Inlet Temperature
Outlet Temperature
Cleaning Schedule Basis
N/A
N/A
N/A
N/A
N/A
N/A
Overhead Nozzles
# of Nozzles
Nozzle Type
Pressure
Flow Rate
Vertical Nozzles
# of Nozzles
Nozzle Type
Pressure
Flow Rate
N/A
N/A
N/A
N/A
Floor Nozzles
# of Nozzles
Nozzle Type
Pressure
Flow Rate
N/A
N/A
N/A
N/A
Filter Type
Bag filters
Dump Frequency
1x Weekly
Dumped & Cleaned Saturday
Screens are cleaned in Same Schedule
# of Nozzles
Nozzle Type
Pressure
Flow Rate
77
V-jet 5070
N/C
N/C
Vertical Nozzles
40
0 degree
N/C
N/C
# of Nozzles
Nozzle Type
Pressure
Flow Rate
4
0 degree
N/A
N/A
# of Nozzles
Nozzle Type
Pressure
Flow Rate
Floor Nozzles
# of Nozzles
Nozzle Type
Pressure
Flow Rate
Plate and frame
27 psi
52 psi
120
129
Time
Overhead Nozzles
Vertical Nozzles
# of Nozzles
Nozzle Type
Pressure
Flow Rate
Pressure
Heat Exchanger
Type
Inlet Pressure
Outlet Pressure
Inlet Temperature
Outlet Temperature
Maintenance Information
52
0 degree
N/C
N/C
65
V-jet 5070
N/C
N/c
Floor Nozzles
Dump Frequency
1X Weekly
Tank is Dumped and Cleaned every Saturday
Screens are Cleaned on the same Schedule
20' 8"
Spray Cleaner 2 - CK166 / 171
56
V-jet 50150
N/C
N/c
Dump Frequency
1X Weekly
Screens are Cleaned on the same Schedule
28' 8"
82' 4"
28' 5"
Immersion Cleaner - CK166 / 171
Product ID
Product ID 2
Product ID 3
Concentration %
Free Alkalinity
Total Alkalinity
Ph Range
Entrance Spray Information
Chemkleen 166HP
Chemkleen 171A
Overhead Nozzles
N/A
# of Nozzles
30
N/C
Nozzle Type
V-jet 5070
1.2-3.0
Pressure
N/C
N/A
Flow Rate
N/C
N/A
Vertical Nozzles
# of Nozzles
30
Nozzle Type
V-jet 5070
84,557
Pressure
N/C
Total Dwell Time
120 secs
Flow Rate
N/C
Exit Spray Information
Temperature
120 - 130
Overflow Rate
N/A
Overhead Nozzles
Counterflow Rate
20 gpms
# of Nozzles
30
Over to Drain Rate
N/A
Nozzle Type
V-jet 5070
Entry Angle
N/C
Pressure
N/C
Exit Angle
N/C
Flow Rate
N/C
44
Vertical Nozzles
N/C
# of Nozzles
30
10 Feet From End Nozzle Type
V-jet 5070
N/A
Pressure
N/C
Flow Rate
N/C
Circulation
Front End Pump Type
Gusher
Number of Front End Pumps
4
Dump Frequency
GPM of Each Front End Pump
N/C
Tank is dumped and cleaned 2 x a year
Pump HP (Each)
50
Total Gallons per Minute (Front)
N/C
# of Front Eductor Headers
22
Exit Pump Type
N/A
Number of Exit Pumps
N/A
GPM of Each Exit End Pump
N/A
Pump HP (Each)
N/A
Total Gallons per Minute (Exit)
N/A
# of Exit Eductor Headers
N/A
1
Diaphgram
3
2
4
Source
Total Alkalinity
Ph Range
Bag
200
28
4
7
No
Microns:
Number of Filters:
# of Vessels:
Bags per Vessel:
Do you use Magnets:
Change Point:
Pressure
Heat Exchanger
Plate and Frame
16 psi
40 psi
122
125
Time
City
0 - 3.5
7-7.9
12,731
30 secs
Ambient
15 gpms
N/A
N/A
V-Jet 5070
346
N/C
N/A
N/A
Total Dwell Time
Temperature
Overflow Rate
Counterflow Rate
Over to Drain Rate
Total Header Rings
Total Flow
8 Feet From End
Gusher
3
50
N/C
N/C
Filtering
Filter Type
Bags
200
28
4
7
No
Microns:
Number of Filters:
# of Vessels:
Bags per Vessel:
Do you use Magnets:
Change Point:
N/A
Heat Exchanger
Type
N/A
Inlet Pressure
N/A
Outlet Pressure
N/A
N/A
Overhead Nozzles
# of Nozzles
Nozzle Type
Pressure
Flow Rate
82' 10"
Rinse Conditioner - Immersion
Total Titanium (PPM)
Filtereed Titanium (PPM)
Ph Range
Total Dwell Time
Temperature
Overflow Rate
Counterflow Rate
Over to Drain Rate
Entry Angle
Exit Angle
120
V-jet 5070
N/C
N/C
Circulation
Front End Pump Type
Pump HP (Each)
Exit Pump Type
Pump HP (Each)
No
Filtering
Filter Type
Microns:
Number of Filters:
# of Vessels:
Bags per Vessel:
Do you use Magnets:
Change Point:
120
V-jet 5070
N/C
N/C
84
V-jet 50150
N/C
N/C
Dump Frequency
1x Weekly
Screens are cleaned on Same Schedule
Type
Inlet Pressure
Outlet Pressure
N/A
N/A
N/A
N/A
2
K-Jet
NC
NC
Vertical Nozzles
# of Nozzles
Nozzle Type
Pressure
Flow Rate
Product ID
Free Acidity
Total Acidity
Liquid Additive
Chemfos 700Rcan
.65-.90
13-19
1.5-2.3
Test Method:
Flouride (PPM)
N/A
112,478
Total Dwell Time
120secs
Temperature
120-130
Overflow Rate
Counterflow Rate
N/A
Over to Drain Rate
N/A
Entry Angle
45 Degree
Exit Angle
45 Degree
28
N/C
10 Feet From End
N/C
Circulation
gusher
2
N/C
30
N/C
14
Gusher
2
N/A
40
N/C
10
Front End Pump Type
Pump HP (Each)
Exit Pump Type
Pump HP (Each)
1
Pulsatron
3
2
Pulsatron
4
2
K-Jet
NC
NC
Dump Frequency
Weekly
Tank is Dumped and Cleaned weekly
Screens are Cleaned Weekly
No
Filtering
Filter Type
Microns:
Number of Filters:
# of Vessels:
Bags per Vessel:
Do you use Magnets:
Change Point:
Filter Press
N/A
N/A
N/A
N/A
No
N/A
Heat Exchanger
N/A
Chemical Feed Harness
Overhead Nozzles
# of Nozzles
Nozzle Type
Pressure
Flow Rate
36' 5"
Phosphate - CF700Rcan
Bags
100
6
1
6
No
Heat Exchanger
Floor Nozzles
# of Nozzles
Nozzle Type
Pressure
Flow Rate
Gusher
2
N/C
40
N/C
14
N/A
N/A
N/A
N/A
N/A
N/A
1
Pulsatron
3
2
4
Vertical Nozzles
# of Nozzles
Nozzle Type
Pressure
Flow Rate
2.5>ppm
N/a
7-7.9
44,859
120 secs
Ambient
N/A
N/A
N/A
45 degree
45 degree
24
N/C
10 Feet From End
N/C
N/A
Circulation
Pump Type
Number of Pumps
Pump HP
Gallons Per Minute
Risers
No
Filtering
Filter Type
Type
Inlet Pressure
Outlet Pressure
Inlet Temperature
Outlet Temperature
City Water - Spray Rinse
Type
Plate and Frame
Inlet Pressure
20
Outlet Pressure
34
Inlet Temperature
120
Outlet Temperature
125
Time and/or Pressure
Overhead Nozzles
# of Nozzles
Nozzle Type
Pressure
Flow Rate
32
V-jet 5070
N/C
N/C
Vertical Nozzles
# of Nozzles
Nozzle Type
Pressure
Flow Rate
32
V-jet 5070
N/C
N/C
Dump Frequency
1x Yearly
Tank is Decanted and Chemically
Cleaned once a year.
Screens are cleaned weekly
PHOSPHATE STAGES 8-13
Times:
:17
:37
Stage Description:
Stage 8
Zone Description: City Water Spray
Drain Zone
1:24
:36
1:47
Drain Zone
Not in Use
Stage 9
City Water Immersion
:47
:27
Drain Zone
Recirc. DI Rinse
1:05
Stage 11
Drain and Observation Area
Stage 10
1:49
1:47
Stage 12
Recirc. DI Water Immersion
Drain Zone
:37
:09
Stage 13
Virgin DI Rinse
Drain Zone
Conveyor Turns
180 Degrees
To E-Coat
and Heads in the
Opposite
Direction
From Stage 7
Shown Compressed
Length in Feet:
13'
28' 8"
64' 7"
City Water - Spray Rinse
Source
Total Acid
Ph Range
Total Dwell Time
Temperature
Overflow Rate
Counterflow Rate
Over to Drain Rate
Total Header Rings
Total Flow
City
0-1.0
N/A
5711 gals
15 secs
ambient
15 gpms
N/A
N/A
22
186
N/C
N/A
N/A
10 Feet From End
N/A
Circulation
Pump Type
Number of Pumps
Pump HP
Gallons Per Minute
Risers
gusher
2
40
N/C
2
Filtering
Filter Type
Bags
100
28
4
7
Microns:
Number of Filters:
# of Vessels:
Bags per Vessel:
Do you use Magnets:
Change Point:
Pressure
City
0-1.0
N/A
44,859
45secs
ambient
N/C
20 gpms
N/A
45 degree
45 degree
24
N/C
Total Dwell Time
Temperature
Overflow Rate
Counterflow Rate
Over to Drain Rate
Entry Angle
Exit Angle
8 feet from end
N/C
Circulation
Front End Pump Type
Pump HP (Each)
Exit Pump Type
Pump HP (Each)
Shown Compressed
82' 10"
City Water - Immersion Rinse
Source
Total Acid
Ph Range
Overhead Nozzles
13
V-jet 5070
N/C
N/C
Vertical Nozzles
# of Nozzles
14
Nozzle Type
V-jet 5070
Pressure
N/C
Flow Rate
N/C
Overhead Nozzles
# of Nozzles
Nozzle Type
Pressure
Flow Rate
32
N/A
N/A
N/A
Source
Total Alkalinity
Ph Range
Total Dwell Time
Temperature
Overflow Rate
Counterflow Rate
Over to Drain Rate
Entry Angle
Exit Angle
Vertical Nozzles
gusher
2
N/C
40
N/C
14
N/A
N/A
N/A
N/A
N/A
3
# of Nozzles
Nozzle Type
Pressure
Flow Rate
Filter Type
Microns:
Number of Filters:
20' 8"
No Immersion Process
# of Nozzles
Nozzle Type
Pressure
Flow Rate
36' 4"
-
-
Circulation
32
N/A
N/A
N/A
Dump Frequency
1X Weekly
Tank is Dumped and Cleaned
every Saturday
Screens are cleaned on Same
Schedule
Front End Pump Type
Pump HP (Each)
Exit Pump Type
Pump HP (Each)
Filtering
No
Heat Exchanger
28' 5"
-
Filter Type
50'
Total Dwell Time
Temperature
Overflow Rate
Counterflow Rate
Over to Drain Rate
Total Header Rings
Total Flow
Make-up DI
N/A
500mmhos
12,731
30secs
ambient
15 gpm
N/A
N/A
13
356
N/C
N/A
N/A
10 Feet From End
N/A
Circulation
Pump Type
Number of Pumps
Pump HP
Gallons Per Minute
Risers
gusher
3
50
N/C
3
Filtering
Filter Type
bags
100
28
4
7
Microns:
Number of Filters:
# of Vessels:
Bags per Vessel:
Do you use Magnets:
-
Change Point:
Type
N/A
Pressure
Heat Exchanger
28' 4"
Recirc DI - Immersion Rinse
Virgin DI
N/A
50 mmhos
44,859
120 secs
ambient
15 gpm's
N/A
N/A
45 degrees
45 degrees
24
10 gpm's
Total Dwell Time
Temperature
Overflow Rate
Counterflow Rate
Over to Drain Rate
Entry Angle
Exit Angle
5 feet from end
N/C
Circulation
Front End Pump Type
Pump HP (Each)
Exit Pump Type
Pump HP (Each)
Filter Type
Microns:
Number of Filters:
Virgin DI - Spray Rinse
Overhead Nozzles
# of Nozzles
Nozzle Type
Pressure
Flow Rate
32
V-jet 5070
N/C
N/C
Vertical Nozzles
# of Nozzles
32
Nozzle Type
V-jet 5070
Pressure
N/C
Flow Rate
N/C
Overhead Nozzles
# of Nozzles
Nozzle Type
Pressure
Flow Rate
32
V-jet 5070
N/C
N/C
Vertical Nozzles
Gushers
2
N/C
40
N/C
12
N/A
N/A
N/A
N/A
N/A
12
Filtering
No
Microns:
Number of Filters:
82' 10"
Fill Source
Ph Range
Max Conductivity
Expanded
6' 11"
Shown Compressed
84'
Recirc DI - Spray Rinse
Fill Source
Ph Range
Max Conductivity
Filtering
bags
100
28
Total Time
for Process
27:25
# of Nozzles
Nozzle Type
Pressure
Flow Rate
32
V-jet 5070
N/C
N/C
Dump Frequency
Tank is treated with Hydrogen Peroxide
weekly on Saturday
Screens are cleaned weekly on Saturday
Soucre
Ph Range
Max Conductivity
Total Dwell Time
Temperature
Overflow Rate
Counterflow Rate
Over to Drain Rate
Total Header Rings
Total Flow
Plant DI
N/A
50mmhos
N/A
10 secs
Ambient
N/A
15 gpm's
N/A
1
12
15 gpm's
N/A
N/A
10 Feet From End
N/A
Circulation
Pump Type
Number of Pumps
Pump HP
Gallons Per Minute
Risers
N/C
N/C
N/C
N/C
N/C
Filtering
Filter Type
Microns:
Number of Filters:
# of Vessels:
Bags per Vessel:
N/A
N/A
N/A
N/A
N/A
Do you use Magnets:
N/A
Change Point:
N/A
bags
25
21
# of Nozzles
14
Overhead Nozzles
Type
N/A
Inlet Pressure
N/A
# of Vessels:
4
# of Vessels:
-
Inlet Pressure
N/A
# of Vessels:
3
Nozzle Type
V-jet 5070
Outlet Pressure
N/A
N/A
Bags per Vessel:
Do you use Magnets:
Change Point:
7
No
Bags per Vessel:
Do you use Magnets:
Change Point:
-
Outlet Pressure
N/A
N/A
Bags per Vessel:
Do you use Magnets:
Change Point:
7
No
Pressure
Flow Rate
N/C
15 gpm's
Overhead Nozzles
# of Nozzles
Nozzle Type
Pressure
Flow Rate
78
V-jet 5070
N/C
N/C
Vertical Nozzles
# of Nozzles
Nozzle Type
Pressure
Flow Rate
78
V-jet 5070
N/C
N/C
Pressure
Heat Exchanger
Type
Inlet Pressure
Outlet Pressure
Type
Inlet Pressure
Outlet Pressure
Dump Frequency
Overhead Nozzles
-
Heat Exchanger
N/A
N/A
N/A
N/A
# of Nozzles
Nozzle Type
Pressure
Flow Rate
Vertical Nozzles
# of Nozzles
Nozzle Type
Pressure
Flow Rate
Floor Nozzles
# of Nozzles
Nozzle Type
Pressure
Flow Rate
136
V-jet 5070
N/C
N/C
136
V-jet 5070
N/C
N/C
Floor Nozzles
40
V-jet 50151
N/C
N/C
Dump Frequency
1x Weekly
Screens are cleaned on Same Schedule
# of Nozzles
Nozzle Type
Pressure
Flow Rate
Vertical Nozzles
Pressure
Heat Exchanger
Type
Inlet Pressure
Outlet Pressure
N/A
N/A
N/A
N/A
# of Nozzles
Nozzle Type
Pressure
Flow Rate
14
V-jet 5070
N/C
15 gpm's
Floor Nozzles
# of Nozzles
Nozzle Type
Pressure
Flow Rate
N/A
N/A
N/A
N/A
84
V-jet 50100
N/C
N/C
Dump Frequency
1x Weekly
Tank is Dumped and Cleaned on Saturday
Screens are cleaned on the same schedule
Stage is treated weekly with 25 gallons of
hydrogen peroxide
Dump Frequency
N/A
Inside an Automotive Phosphate Machine
Inside an Automotive Phosphate Machine
Or more simply……….
Cleaner
STAGE 1
DELUGE
SPRAY
WASH
MANUAL
PREWIPE
STAGE 2
HIGH
PRESSURE
CAUSTIC
SPRAY
DRAIN
Condition
Rinse
STAGE 3
CLEANER DIP
DRAIN
STAGE 6
SURFACE
CONDITIONER DIP
(IN/OUT)
STAGE 4 STAGE 5
WATER
WATER
SPRAY
RINSE
DRAIN
DRAIN
DRAIN
VEST./
AIR
SEAL
TRAVEL
TRAVEL
Phosphate
STAGE 7
PHOSPHATE DIP
Rinse
STAGE 8
WATER
SPRAY
RINSE
DRAIN DRAIN
Rinse
Passivation
(Spray)
Water
Rinse
STAGE 9 STAGE 10
11
WATER PASSIVATION STAGE
D.I.
SPRAY
SPRAY
SPRAY
RINSE
DRAIN
DRAIN
DRAIN
TRAVEL
(Spray
STAGE 12
DEIONIZED
WATER DIP
(IN/OUT)
STAGE 13
VIRGIN D.I. ) DI
WATER
SPRAY (HALO) Rinse
DRAIN
DRAIN
TRAVEL
Dip
Rinse
Claimed Zr Benefits







60% reduction in DI rinse water
15% electricity reduction (pumps)
40% energy reduction (heat exchangers)
Reduced complexity
Smaller footprint
Increased throughput
No phosphate incrustation → fewer boil-outs
How Is It Done?
STAGE ELIMINATION
Pre-Cleaner
Stage
Deluge
spray
Cleaner
spray
Cleaner
dip
H2O rinse
dip
Activation
dip
Phosphate
dip
H2O rinse Passivation
dip
dip
DI dip &
virgin
DI spray
Pre-Cleaner
Stage
Deluge
spray
Cleaner
spray
Cleaner
dip
H2O rinse
dip
Activation
dip
Zirconium
dip
H2O rinse Passivation
dip
dip
DI dip &
virgin
DI spray
Replace Zinc Phosphate Zn3(PO4)2
with Zirconium Oxide ZrO2

Zn + P (virtually) eliminated from chemistry!!!

Process control simplified (~100,000-gal
phosphate tank needs temp control of 125+/-3 oF)
• High temp causes excessive formation
• Low temp causes unsatisfactory phosphate/steel reaction

Eliminate activation & passivation stages and their
associated chemistries
Zinc Phosphate Bath Converted to Zr

Zn, Ni, Mn, & P eliminated from coating chemistry!!!
NOTE: SOME P REMAINS IN CLEANER CHEMISTRY

Polycrystalline Zn3(PO4)2 becomes amorphous ZrO2

Lower coating weight leads to shortened processing time
(namely, reduced footprint and increased throughput)
Corrosion Performance
Better on Al – slightly worse for EG
GM 9540P
621-415
Ford APGE
European VDA
Dirty Little Secrets
•
Zirconium was present in some manufacturer’s
passivation steps (though much less)
•
Zinc is not eliminated – acidic leaching from
galvanized substrate (though much less)
•
Phosphate is not eliminated – still present in some
cleaners (though much less)
•
Cu/F remain in some manufacturer’s formulations
Zr Treatment - Transition Metals
Hydroxide precipitation works on:
Zinc
Chromium
Tin
Mercury
Iron
Silver
Nickel
Copper
Cobalt
Aluminum
Cadmium
Arsenic
so why not Zirconium???
Hydroxide Precipitation
Precipitating Agents:
 Calcium Hydroxide - Ca(OH)2
 Magnesium Hydroxide - Mg(OH)2
 Sodium Hydroxide - Na(OH)
Zn2+ (aq) + 2OH- (aq) = Zn(OH)2 (s)
Cu2+ (aq) + 2OH- (aq) = Cu(OH)2 (s)
Ni2+ (aq) + 2OH- (aq) = Ni(OH)2 (s)
Solubility Product Constant (KSP)
The amount of any ionic species that can be placed in
solution is determined by it’s solubility expression:
Zn(OH)2
Zn2+ + 2OH-
KZn(OH)2 = [Zn+] [OH-]2
(Which would suggest that the highest pH results in the lowest zinc
concentration – which isn’t the case.)
Compound
Formula
Ksp (25oC)
Aluminum hydroxide
Al(OH)3
3x10-34
Cadmium hydroxide
Cd(OH)2
7.2x10-15
Copper (II) hydroxide
Cu(OH)2
4.8x10-20
Lead (II) hydroxide
Pb(OH)2
1.43x10-20
Lead (IV) hydroxide
Pb(OH)4
3.2x10-66
Mercury hydroxide
Hg(OH)2
3.2x10-26
Nickel hydroxide
Ni(OH)2
5.48x10-16
Zinc hydroxide
Zn(OH)2
3x10-17
Zirconium hydroxide
Zr(OH)2
6.3x10-49
Zr Treatment
Most metal ions are multivalent so their solubility is proportional to the
power of the hydroxyl ion:
M(OH)x
M+x + xOH-
KSP = [M+x] [OH-]x
Zr Treatment
So why isn’t higher pH better?
Zn2+ (aq) + 2OH- (aq)
Zn(OH)2 (s) + OH- (aq)
Zn(OH)3- (aq) + OH- (aq)
Etc.
Etc.
Zn(OH)2 (s)
Good thing!
Zn(OH)3- (aq)
Zn(OH)4-2 (aq)
Bad
Bad
Hydroxide Precipitation
Zr Treatment – Henkel Laboratory Study
3
Baths Treated:
Fresh 3% laboratory standard
Ford TCAP Zr bath
Ford TCAP bath diluted 3 times
 Two
Methods Used:
• A: To pH 9.0 with Ca(OH)2, FeCl3, polymer
• B: Acidify to pH 2.0 then method A above
Final zinc blamed on “experimental errors”
Zr Treatment – Ford Field Study
Zr Treatment – StAP WWTP Data
Phosphate Batches
Zirconium Routine
Began bleeding in cleaner dumps and the majority of
batches didn’t require treatment (compliant coming in).
Stage 7 always required Zn treatment (up to 900 ppm before
stage becomes unuseable).
Zirconium Toxicity
CDC: “ziconium coumpounds posses a low order of toxicity”
(ZrO2 is used for hip replacements)
Zr Inhibition of Activated Sludge?
Not here……
Not here……
Not here……
USEPA ECOTOX Report
Zr Inhibition of Activated Sludge
(It’s pretty high)
Abstract Our contribution to Zr environmental hazard, arrived at by means of bioassays
on bacteria, microscopic algae and fish, confirms the hypothesis that Zr
has low toxicity. Toxic effects revealed with the Microtox test may
be attributed to pH rather than specifically to Zr (5 min. EC50
> 4.3 mg/L). Fish assays also confirmed the low toxicity of Zr (96-hr LC50 > 20 mg
L–1; 96 hr minimal stress concentration > 20 mg L–1; Mutagenicity (Fluctuation test) and
genotoxicity (S.O.S. Chromotest) assays failed to show any DNA-related effects linked to
this metal. Only the algal assays (ATP energy stress) demonstrated genuine toxicity at Zr
concentrations between 1.3 and 2.5 mg L–1.
Zirconium Toxicity Assessment using Bacteria, Algae and Fish Assays
P. Couture, C. Blaise, D. Cluis and C. Bastien
1989 The Netherlands
F019 Issue…….

F019 is one of EPA’s RCRA hazardous waste
listings, which include wastes that are generated
from processes such as chromating,
phosphating, metal coloring and/or immersion
plating. F019 wastes are defined as
wastewater treatment sludges from the
chemical conversion coating of aluminum
(except from zirconium phosphating in aluminum
can washing).
F019 Issue…….
The USEPA Office of Resource Conservation and
Recovery made a determination in 2009 that the
zirconium oxide process is not chemical
conversion coating.
Therefore wastewater treatment sludges
generated are not covered by the F019 listing.
Is Zr Regulated?
Is Zr Regulated?
Questions?

Zirconium Oxide in Metal Finishing

Transcription

Similar documents

Mattress PM320

Nuovo sistema ad iniezione sequenziale GPL e METANO

Lift Station Commander

Benefits of Hydrovac Daylighting (2.2 Meg)

VHF/FM FREQUENCY HOPPING RADIO SETS (9600 Series)

Schede KF - Pratissoli Pompe

Technical Data

POWER SYSTEM IN OIL AND GAS INDUSTRY

Depliant Ugelli soffianti a piu` canali Serie UGS