Nyob rau hauv sulfur rov qab units rau roj av refining, natural gas purification thiab thee chemical nroj tsuag, pa ob-theem thiab peb-theem Claus txheej txheem raug txwv los ntawm thermodynamic equilibrium, nrog rau qhov siab tshaj plaws tag nrho cov sulfur rov qab tus nqi ntawm tsuas yog 95% ~ 97%. Cov pa roj av muaj cov seem SO₂, COS, CS₂ thiab gaseous elemental sulfur, uas tsis ua raws li lub teb chaws emission qauv tam sim no rau cov pa phem hauv kev lag luam petrochemical. SCOT (Shell Claus Off-gas Treating), Plhaub Claus tawm- cov txheej txheem kho roj, yog qhov siv ntau tshaj plaws hydrogenation-raws li qhov sib sib zog nqus tail gas kho tshuab hauv kev lag luam refining thiab tshuaj lom neeg. Nws ua hauj lwm nyob rau hauv tandem nrog lub ntsiab Claus chav tsev kom paub qhov tob tshem tawm thiab kev pab rov qab ntawm sulfides.
1. Txheej txheem kev tsim kho thiab kev siv keeb kwm yav dhau
Tsim los ntawm Shell Netherlands, cov txheej txheem SCOT tau tsim muaj nyob rau xyoo 1973 thiab tsim los ua kev tshaj tawm - cov txheej txheem kho kom haum nrog Claus sulfur rov qab. Ua raws li kev siv ultra- cov qauv qis emission nyob rau hauv Tuam Tshoj txoj kev lag luam petrochemical, ncaj qha tso pa tawm ntawm tus Tsov tus tw los ntawm cov pa Claus units ua rau muaj emission ntau dhau. Raws li qhov tshwm sim, SCOT tau dhau los ua qhov chaw kho cov pa roj carbon monoxide rau cov refineries, LNG terminals thiab thee- mus rau -gas tej yaam num. Nws nce tag nrho cov sulfur rov qab tus nqi ntawm chav tsev ua ke kom siab dua 99.9%, ua raws li lub teb chaws ultra- qis SO₂ emission tswj cov cai.
2. Cov txheej txheem tshuaj tiv thaiv
Tag nrho cov txheej txheem muaj peb ntu tseem ceeb: txo hydrogenation, hnyav nqus thiab hnyav rov tsim dua tshiab.
Tail gas ntws mus rau hauv hydrogenation reactor, qhov twg txo thiab hydrolysis tshwm sim nyob rau hauv Co-Mo sulfur- resistant hydrogenation catalysts ntawm 270 ~ 310℃nyob rau hauv me ntsis zoo siab. SO₂ thiab S₈ yog hydrogenated rau hauv H₂S, thaum organic sulfur hom COS thiab CS₂ yog hydrolyzed rau hauv H₂S.
Txias hydrogenated tail gas nkag mus rau hauv lub absorber, qhov twg MDEA (methyldiethanolamine) selective hnyav absorbs H₂S. Purified flue gas yog incinerated ua ntej mus txog emission qauv. Cov nplua nuj amine hnyav raug xa mus rau lub tshuab hluav taws xob rau kev tshem tawm, ua kom muaj txiaj ntsig siab -concentration H₂S uas rov qab mus rau Claus rauv rau kev tsim cov sulfur.
3. Technical Advantages
Piv nrog rau kev xaiv oxidation thiab kua -theem oxidation tail gas txheej txheem, SCOT khav theeb ua haujlwm ruaj khov:
①High conversion tus nqi ntawm cov organic sulfur, haum rau kev ua hauj lwm tej yam kev mob nrog fluctuating siab thiab tsawg sulfur loads;
② Kev xaiv siab ntawm amine hnyav, qis co- nqus CO₂ thiab tswj tau lub zog noj;
③Hydrogenation catalysts muaj zog tiv thaiv cov hlau hnyav thiab sulfide lom, nrog rau kev pab cuam lub neej ntawm 5 mus rau 8 xyoo;
④ Kaw- txheej txheem voj voog yam tsis muaj kev phom sij thib ob, thiab los ntawm - cov khoom sulfur mus txog qib qib kev lag luam.
4. Muaj nuj nqis thov
Hloov kho SCOT cov txheej txheem yog universally nruab rau leej faj rov qab units nyob rau hauv loj domestic integrated refining thiab tshuaj complexes, ntsuas ib puag ncig ua raws cai thiab sulfur resources. Cov thev naus laus zis no rhuav tshem cov txheej txheem thev naus laus zis ntawm cov txheej txheem Claus ib txwm, txo cov kev ua haujlwm thiab kev saib xyuas nyuaj ntawm cov cuab yeej kho roj av, thiab ua raws cov qib qis - carbon thiab huv cov hom phiaj ntawm kev lag luam petrochemical. Nws ua haujlwm raws li tus qauv thiab cov ntsiab lus tseem ceeb-kev kho tshuab hauv cov xov tooj ntawm cov xov tooj cua tag nrho.