Ho chesoa ha mashala litsing tsa tlhahiso ea motlakase ho hlahisa litšila tse tiileng, joalo ka molora o ka tlase le o fofang, le khase ea flue e ntšetsoang sepakapakeng. Limela tse ngata lia hlokahala ho tlosa mesi ea SOx ho tsoa khaseng ea flue ho sebelisoa litsamaiso tsa flue gas desulfurization (FGD). Mekhoa e meraro e ka sehloohong ea FGD e sebelisoang US ke ho hlatsoa ka metsi (85% ea lits'ebetso), ho hlatsoa ka metsi (12%), le ente ea sorbent e omileng (3%). Hangata li-scrubbers tse metsi li tlosa ho feta 90% ea SOx, ha li bapisoa le li-scrubbers tse omileng, tse tlosang 80%. Sengoloa sena se hlahisa mahlale a morao-rao a ho phekola metsi a litšila a hlahisoang ke metsi.Mekhoa ea FGD.
Metheo ea Metsi ea FGD
Mahlale a Wet FGD a na le karolo e tšoanang ea sehakisi sa lerōle le karolo ea ho ntša metsi ka lintho tse tiileng. Mefuta e fapaneng ea li-absorber e sebelisitsoe, ho kenyeletsoa litora tse pakiloeng le tsa terei, li-scrubbers tsa venturi, le li-scrubbers tsa spray karolong ea sehakisi. Li-absorber li felisa likhase tse nang le asiti ka alkaline slurry ea lime, sodium hydroxide, kapa limestone. Ka mabaka a 'maloa a moruo, li-scrubbers tse ncha li atisa ho sebelisa lerōle la limestone.
Ha lejoe la mokoetla le arabela le SOx maemong a ho fokotsa a monyang, SO 2 (karolo e kgolo ya SOx) e fetoha sulfite, mme ho hlahiswa lerōle le nang le calcium sulfite. Ditsamaiso tsa FGD tsa pejana (tse bitswang oxidation ya tlhaho kapa ditsamaiso tsa oxidation tse thibetsweng) di hlahisitse sehlahiswa se seng sa calcium sulfite. E ntjha.Mekhoa ea FGDSebelisa sesebelisoa sa ho ntša oksijene moo calcium sulfite slurry e fetoloang ho ba calcium sulfate (gypsum); tsena li bitsoa litsamaiso tsa FGD tsa limestone forced oxidation (LSFO).
Mekhoa e tloaelehileng ea sejoale-joale ea LSFO FGD e sebelisa sesebelisoa sa ho fafatsa tora se nang le sesebelisoa sa ho ntša oksijene se kopaneng botlaaseng (Setšoantšo sa 1) kapa sistimi ea ho ntša metsi a jet bubbler. Karolong ka 'ngoe ea khase e monngoa ka har'a lerōle la mokoetla tlas'a maemo a chefo; lerōle ebe le fetela sebakeng sa ho ntša oksijene kapa sebaka sa karabelo, moo sulfite e fetoloang ho ba sulfate, 'me gypsum ea fetoha. Nako ea ho koalloa ha hydraulic ka har'a sesebelisoa sa ho ntša oksijene ke metsotso e ka bang 20.
1. Sistimi ea FGD ea ho fafatsa ea limestone ka lebaka la ho qobelloa ho oxidation (LSFO). Ka har'a LSFO scrubber slurry e fetela ho reactor, moo moea o eketsoang ho qobella ho oxidation ea sulfite ho ba sulfate. Ho bonahala eka ho oxidation ena ho fetola selenite ho ba selenate, e leng se fellang ka mathata a kalafo hamorao. Mohloli: CH2M HILL
Hangata litsamaiso tsena li sebetsa ka lintho tse tiileng tse emisitsoeng tsa 14% ho isa ho 18%. Lintho tse tiileng tse emisitsoeng li na le lintho tse tiileng tsa gypsum tse ntle le tse mahoashe, molora o fofang, le thepa e sa sebetseng e kenngoang le lejoe la mokoetla. Ha lintho tse tiileng li fihla moeling o ka holimo, lerōle lea hloekisoa. Boholo ba litsamaiso tsa LSFO FGD li sebelisa mekhoa ea ho arola lintho tse tiileng tsa mechine le ho tlosa metsi ho arola gypsum le lintho tse ling tse tiileng ho tsoa metsing a hloekisang (Setšoantšo sa 2).
2. Sistimi ea ho tlosa metsi ka gypsum ea FGD. Sistimi e tloaelehileng ea ho tlosa metsi ka gypsum, likaroloana tse ka har'a purge li aroloa, kapa li aroloa, ka likaroloana tse mahoashe le tse tšesaane. Likaroloana tse tšesaane li aroloa ka ho phalla ho tsoa ho hydroclone ho hlahisa phallo e ka tlase e nang le boholo ba likristale tse kholo tsa gypsum (tse ka rekisoang) tse ka tlosoang metsi ho ea boemong bo tlase ba mongobo ka sistimi ea ho tlosa metsi ka lebanta la vacuum. Mohloli: CH2M HILL
Mekhoa e meng ea FGD e sebelisa li-thickeners tsa matla a khoheli kapa matamo a ho sesa bakeng sa ho arola le ho tlosa metsi a thata, 'me e meng e sebelisa li-centrifuge kapa mekhoa ea ho tlosa metsi a rotary vacuum drum, empa boholo ba mekhoa e mecha e sebelisa li-hydroclone le mabanta a vacuum. Tse ling li ka sebelisa li-hydroclone tse peli ka tatellano ho eketsa ho tlosoa ha lintho tse thata tsamaisong ea ho tlosa metsi. Karolo ea phallo ea hydroclone e ka khutlisetsoa tsamaisong ea FGD ho fokotsa phallo ea metsi a litšila.
Ho ntsha metsi ho ka boela ha qalwa ha ho na le ho bokellana ha di-chloride ka hara seretse sa FGD, ho hlokehang ke meedi e behilweng ke ho hanyetsa ho bola ha thepa ya kaho ya sistimi ya FGD.
Litšobotsi tsa Metsi a Litšila a FGD
Lintho tse ngata tse fapaneng li ama sebopeho sa metsi a litšila a FGD, joalo ka sebopeho sa mashala le lejoe la mokoetla, mofuta oa scrubber, le sistimi ea ho tlosa metsi ea gypsum e sebelisoang. Mashala a kenya letsoho likhase tse nang le asiti - joalo ka li-chloride, fluoride le sulfate - hammoho le litšepe tse feto-fetohang, ho kenyeletsoa arsenic, mercury, selenium, boron, cadmium le zinc. Lejoe la mokoetla le kenya letsoho tšepe le aluminium (ho tsoa liminerale tsa letsopa) ho ea metsing a litšila a FGD. Hangata lejoe la mokoetla le silakanngoa ka har'a polasi ea bolo e metsi, 'me khoholeho le ho bola ha libolo li kenya letsoho tšepe ho slurry ea lejoe la mokoetla. Letsopa le atisa ho kenya letsoho ho se sebetseng hantle, e leng e 'ngoe ea mabaka a etsang hore metsi a litšila a hloekisoe ho scrubber.
Ho tsoa ho: Thomas E. Higgins, PhD, PE; A. Thomas Sandy, PE; le Silas W. Givens, PE.
Email: caroline@rbsic-sisic.com
Nako ea poso: Phato-04-2018