Laadi alla infomaterjal

Transcription

Laadi alla infomaterjal
Viis aastat kestnud Kohtla-Järve tööstusjäätmete ja poolkoksi
prügila sulgemistööde raames teisaldati 6 miljonit m³ mäemassiivi,
paigaldati enam kui 8 km pikkune sademevee kogumise süsteem
ning suleti ca 2,5 ha suurused fuussijärved. Väga järsu kaldenurga
all teostatud töid (kõige järsum osa objektist nõlvusega ehk nõlva
kõrguse ja laiuse suhtega oli 1:1) muutsid veelgi keerulisemaks
2013. aasta algul avastatud põlengud.
Põlengu summutamiseks ja õhu juurdepääsu takistamiseks
kaeti kolded üle 2 meetri paksuse vana tuha ja vähese
orgaanika sisaldusega ja halva soojusjuhtivusega poolkoksi
isolatsioonikihiga. Vaatamata õhu juurdepääsu sulgemisele,
põleng koheselt ei kustu, kuid põlenguprotsessid aeglustuvad,
mistõttu sisaldas põlenguala kattekonstruktsioon ka gaaside
kogumise ja väljutamise kihti, mis rajati paekivi killustikust
fraktsiooniga 32..64 mm. Üle 0,5 m paksune gaasikogumiskiht
jäeti gaaside väljumiseks põlenguala ühelt küljelt avatuks.
Prügila katmisel anti ladestule kõigepealt planeeritud kuju
ning pealispind tihendati ja tasandati. Tagamaks nõudeid
suletud ladestu kattekihi veejuhtivusele, kaeti ladestu
bentoniitmattidega. Vettpidavale mineraalkihile veesurve
alandamiseks ja läbi kattekihi filtreerunud sademevee ära
juhtimiseks kasutati drenaažimatti, mis paigaldati otse
bentoniitmatile. Nõlvadel, mille nõlvus on ≥ 1:2, kasutati
kattekihi stabiilsuse tagamiseks lisaks geovõrku, mis paigaldati
bentoniit- ja drenaažimattide peale. Kattekihina kasutati
värsket poolkoksi. Hüdrokülvi tehti objektil kokku umbes 60
hektaril, arukaskedest metsa istutati koos aluse hüdrokülviga
kokku ligikaudu 24 hektaril.
Tööstusjäätmete ja poolkoksi prügilate sulgemine Kohtla-Järvel
Aadress: Tellija : Tööde iseloom: Ehitusperiood: Kohtla-Järve, Ida-Virumaa
Keskkonnaministeerium
prügilate sulgemine
2009-2014
A hill of mine waste amounting to 6 million m³ was relocated, 84
hectares were replanted, a rainwater collection system more than 8
km long was installed, and 2.5 hectare lakes containing liquid oil shale
mining residues were closed – all part of the operation to close the
Kohtla-Järve industrial waste and semi-coke dump in north-eastern
Estonia. The works, undertaken on a very steep slope, were rendered
even more complicated by smouldering fires discovered in early 2013,
which were buried up to 5 metres deep.
To extinguish the blaze and prevent air from reaching it, the burning
areas were covered with a 2-metre-thick layer of old ash and an
insulation layer composed of semi-coke with low organic content and
heat conductivity. In spite of cutting off the access of air, the blaze did
not go out right away, but the combustion processes slowed down, as a
result of which the covering structure of the blaze area also contained a
gas collection and removal layer that in turn was made up of a crushed
limestone with particle size of 32-64 mm. This layer, which was over 0.5
metre thick, was left open on one side to allow gases to exit the blaze
area.
In the course of covering over the dump, the area was first given its
new shape specified in plans, and then the surface was compacted
and levelled. To ensure that water could run along the top layer of the
closed dump, it was covered with bentonite mats. To reduce the water
pressure on the waterproof mineral layer and divert any run-off that
filtered through the covering layer, drainage mats were used, being
installed directly on the bentonite mat. On slopes at an angle of 1:2, a
geo-mesh was used in addition to ensure stability of the covering layer.
The geo-mesh was installed on top of the bentonite and drainage mats.
Fresh semi-coke was used as the covering layer. The hydro-sowing was
performed over a total of about 60 hectares, and a total of about 24
hectares were planted with silver birches using hydro-sowing.
Closing of industrial waste and semi-coke landfill in Kohtla-Järve
Address: Client: Construction type: Construction period: Kohtla-Järve, Ida-Virumaa
Estonian Ministry of the Environment
closing the waste landfill
2009-2014