Kupiswa kwemarasha munzvimbo dzinogadzirwa magetsi kunogadzira marara akaomarara, akadai semadota epasi neanobhururuka, uye gasi rinobuda mumhepo. Mafekitori mazhinji anofanirwa kubvisa SOx kubva mugasi rinobuda mumhepo achishandisa masisitimu e flue gas desulfurization (FGD). Matekinoroji matatu anotungamira eFGD anoshandiswa muUS ndeekukwesha wet (85% yenzvimbo dzakaiswa), kukwesha dry (12%), uye dry sorbent injection (3%). Wet scrubbers anowanzo bvisa anopfuura 90% yeSOx, zvichienzaniswa ne dry scrubbers, ayo anobvisa 80%. Chinyorwa chino chinoratidza matekinoroji emazuva ano ekurapa mvura yakasviba inogadzirwa ne wet.Masisitimu eFGD.
Zvekutanga zveWet FGD
Tekinoroji dzeWet FGD dzine chikamu chereactor ine slurry uye chikamu chekubvisa mvura chakasimba. Mhando dzakasiyana dzezvinwiwa zvakashandiswa, zvinosanganisira machira akapetwa netray, venturi scrubbers, uye spray scrubbers muchikamu chereactor. Zvinwiwa izvi zvinobvisa acidic gasses nealkaline slurry ye lime, sodium hydroxide, kana limestone. Nekuda kwezvikonzero zvakasiyana-siyana zvehupfumi, zvinwiwa zvitsva zvinoshandisa limestone slurry.
Kana limestone ikapindirana neSOx mumamiriro ekuderedza kwechinhu chinonyungudutsa mvura, SO2 (chikamu chikuru cheSOx) inoshandurwa kuita sulfite, uye slurry yakapfuma mucalcium sulfite inogadzirwa. Kare masisitimu eFGD (anonzi natural oxidation kana kuti inhibited oxidation systems) akagadzira calcium sulfite by-product. ZvitsvaMasisitimu eFGDshandisa oxidation reactor umo calcium sulfite slurry inoshandurwa kuita calcium sulfate (gypsum); idzi dzinonzi limestone forced oxidation (LSFO) FGD systems.
Masisitimu emazuva ano eLSFO FGD anoshandisa spray tower absorber ine integral oxidation reactor mu base (Mufananidzo 1) kana jet bubbler system. Mune yega yega gasi rinonyudzwa mu limestone slurry pasi pemamiriro e anoxy; slurry inobva yaenda kune aerobic reactor kana reaction zone, uko sulfite inoshandurwa kuita sulfate, uye gypsum precipitates. Nguva ye hydraulic detention mu oxidation reactor ingangoita maminetsi makumi maviri.
1. Spray column limestone forced oxidation (LSFO) FGD system. MuLSFO scrubber slurry inopinda mureactor, uko mhepo inowedzerwa kuti ioxidation yesulfite ive sulfate. Oxidation iyi inoita seinoshandura selenite kuita selenate, zvichikonzera matambudziko ekurapwa gare gare. Chitubu: CH2M HILL
Masisitimu aya anowanzo shanda nezvinhu zvakasungirirwa zve14% kusvika 18%. Zvinhu zvakasungirirwa zvine gypsum solids dzakapfava uye dzakakora, ash inobhururuka, uye zvinhu zvisina simba zvinounzwa ne limestone. Kana zvinhu zvakasungirirwa zvasvika pamuganhu wepamusoro, slurry inobviswa. Mazhinji masisitimu eLSFO FGD anoshandisa masisitimu ekuparadzanisa zvinhu zvakasungirirwa uye ekudzima mvura kuti aparadzanise gypsum nezvimwe zvinhu zvakasungirirwa kubva mumvura inobviswa mvura (Mufananidzo 2).
2. Sisitimu yekubvisa mvura yegypsum kubva kuFGD. Musisitimu yekubvisa mvura yegypsum yakajairika, zvidimbu zviri mupuringi zvinopatsanurwa kuita zvikamu zvakakora uye zvitete. Zvikamu zvitete zvinopatsanurwa mukuwandisa kubva kuhydroclone kuti zvigadzire mvura iri pasi pemvura inoumbwa nemakristaro makuru egypsum (anogona kutengeswa) anogona kubviswa mvura kusvika pahunyoro hushoma nesisitimu yekubvisa mvura yebhandi revacuum. Chitubu: CH2M HILL
Dzimwe nzira dzeFGD dzinoshandisa zvinosimbisa simba remagetsi kana madziva ekugadzika kuti dzigadzire uye dzibvise mvura, uye dzimwe dzinoshandisa ma centrifuges kana kuti rotary vacuum drum dewatering systems, asi dzimwe nzira itsva dzinoshandisa ma hydroclones nema vacuum belts. Dzimwe dzinogona kushandisa ma hydroclones maviri akatevedzana kuti dziwedzere kubviswa kwemvura mu system yekubvisa mvura. Chikamu chekuwanda kwe hydroclone chinogona kudzoserwa ku system yeFGD kuderedza kuyerera kwemvura yakasviba.
Kubvisa simbi kunogonawo kutanga kana paine kuunganidzwa kwemachloride muFGD slurry, zvichikonzerwa nemiganhu inoiswa nekuramba kwengura kwezvinhu zvekuvaka zveFGD system.
Hunhu hweMvura Yakasviba yeFGD
Zvinhu zvakawanda zvinokanganisa kuumbwa kwemvura yakasviba yeFGD, zvakaita sekugadzirwa kwemarasha nelimestone, rudzi rwekukwesha, uye sisitimu yekubvisa mvura inoshandiswa negypsum. Marasha anobatsira magasi ane acidic - akadai sechlorides, fluorides, uye sulfate - pamwe nesimbi dzinoshanduka, dzinosanganisira arsenic, mercury, selenium, boron, cadmium, uye zinc. Limestone inopa iron nealuminium (kubva muzvicherwa zvevhu) kuenda kumvura yakasviba yeFGD. Limestone inowanzo pwanywa mugayo rebhora rakanyorova, uye kuputsika nekuora kwemabhora kunopa iron kuslurry yelimestone. Ivhu rinowanzo batsira mukusashanda zvakanaka kwemvura yakasviba, inova imwe yezvikonzero zvinoita kuti mvura yakasviba ibviswe muscrubber.
Kubva kuna: Thomas E. Higgins, PhD, PE; A. Thomas Sandy, PE; naSilas W. Givens, PE.
Email: caroline@rbsic-sisic.com
Nguva yekutumira: Nyamavhuvhu-04-2018