Mu njira iliyonse yamakampani yopanga syngas, ndi njira yofunika kwambiri yogwiritsira ntchito kupita patsogolo kwa kusintha kwa mpweya wamadzi kuti asinthe CO kukhala hydrogen.
Kuchita izi ndi njira yosinthika ya exothermic. Kutentha kukakwera, kusintha kofanana kumachepa. Nthawi yomweyo, kuchita izi ndi njira yodziwika bwino yosinthira. Ngati palibe chothandizira, zimakhala zovuta kuchitapo kanthu pa 700. Pakakhala chothandizira, kutentha kwa reaction kumachepa kwambiri. Pogwiritsa ntchito chothandizira kutentha kwambiri, kutentha kwa reaction ndi 300 ~ 500 ° C; Pamene chothandizira kutentha kochepa chikugwiritsidwa ntchito, kutentha kwa reaction ndi 200-400 ° C (tebulo 22). Chifukwa chakuti kuchitapo kanthu ndi isomolecular reaction, kuthamanga sikukhudza kuyanjana kwa reaction, koma ntchito ya pressure imatha kusintha mphamvu yopanga ndi liwiro la reaction.
Pa gawo loyamba la reaction, njirayi ili kutali ndi malire a equilibrium ndipo imayendetsedwa ndi kinetics. Kuonjezera kutentha kumatha kusintha kwambiri liwiro la reaction ndikuwonjezera magwiridwe antchito a process. Pa gawo lotsatira la reaction, kusintha kwa ndondomekoyi kumachepetsedwa ndi thermodynamic equilibrium. Kusintha kwa thermodynamic equilibrium pa kutentha kwakukulu kumakhala kochepa. Chifukwa chake, pa gawo lotsatira la reaction, ntchito yotsika kutentha iyenera kutsatiridwa kuti ikonze kusintha kwa CO. Makhalidwe a thermodynamic ndi kinetic a process amatsimikizira kuti njira yosinthira CO iyenera kugwiritsa ntchito kutentha kosinthasintha.
Pa gawo loyamba la reaction, njirayi ili kutali ndi malire a equilibrium ndipo imayendetsedwa ndi kinetics. Kuonjezera kutentha kumatha kusintha kwambiri liwiro la reaction ndikuwonjezera magwiridwe antchito a process. Pa gawo lotsatira la reaction, kusintha kwa ndondomekoyi kumachepetsedwa ndi thermodynamic equilibrium. Kusintha kwa thermodynamic equilibrium pa kutentha kwakukulu kumakhala kochepa. Chifukwa chake, pa gawo lotsatira la reaction, ntchito yotsika kutentha iyenera kutsatiridwa kuti ikonze kusintha kwa CO. Makhalidwe a thermodynamic ndi kinetic a process amatsimikizira kuti njira yosinthira CO iyenera kugwiritsa ntchito kutentha kosinthasintha.
Chifukwa cha kuletsa kwa reaction balance, ngakhale kuti CO imasinthidwa kwambiri pambuyo pa kusintha kwa mpweya wa madzi kutentha kochepa, kuchuluka kwake kumakhalabe pafupifupi 1%, komwe sikungakwaniritse zofunikira pakugwiritsa ntchito njira zambiri zotsatizana. Mu mafakitale, nthawi zambiri imachotsedwa ndi ma chemical reactions ena. Kusungunuka kwa CO ndi O2 pamaso pa hydrogen yambiri kumapanga CO2, ndipo hydrogen ndi O2 ndizosavuta kuchitapo kanthu. Chifukwa chake, njirayi imadalira kutentha kwa reaction ndi mtundu wa catalyst [29301].
Njira ina yopitira patsogolo ndi hydrogenation ya CO ndi kuchuluka kwa hydrogen komwe kulipo mwachindunji pa nickel based catalyst kuti ipange methane.
Pambuyo pa kusintha kwa mpweya wa m'madzi ndi kuchotsa CO2, zigawo zazikulu za mpweya zimakhala H2 ndi CO2. Mu makampani opanga ammonia, CO2 iyenera kulekanitsidwa kaye. CO2 iyi imatha kupitiliza kuchitapo kanthu ndi ammonia yopangidwa ndi haidrojeni m'gawo lotsatira kuti ipange ammonium bicarbonate, ammonium carbonate kapena urea ndi feteleza ena a mankhwala kuti CO2 igwiritsidwe ntchito bwino kwambiri. Munjira iyi, ukadaulo wolekanitsa CO2 ndi H2 makamaka ndikuwonetsetsa kuti CO2 ikhoza kugwiritsidwanso ntchito.
Pa ntchito za haidrojeni monga ma cell amafuta a pulotoni, haidrojeni yokha ndi yomwe imagwiritsidwa ntchito m'malo mwa CO2. CO2 imakhala mpweya wopanda ntchito, womwe ungafunike kuphatikizidwa ndi njira zina zopangira mchere (monga kupanga calcium carbonate ya mtundu wa chakudya).
Komabe, mu njira zonse zolekanitsa CO2, ndi njira yabwino yogwiritsira ntchito organic amine kapena methanol kuti itenge CO2. Makamaka mu njira yoyamwitsa CO2 ndi methanol pa kutentha kochepa, kusungunuka kwa mpweya wambiri kumawonjezeka pa kutentha kochepa. Kusungunuka kwa haidrojeni kokha sikumachepetsedwa ndi kutentha, ndipo kutentha kukakhala kotsika, kusungunuka kumachepa. Kumasonyeza kusankha bwino kwa kulekanitsa H2.
Pobwezeretsa CO2, poganizira zopewa kuwonongeka kwa haidrojeni, yesetsani kupewa kugwiritsa ntchito zinthu zodula (monga caustic soda) zomwe zingagwirizane kwambiri ndi CO2, kuti mutsimikizire kuti njira yogwiritsira ntchito zinthuyi ndi yotsika mtengo.
Nthawi yotumizira: Disembala-10-2021