Uyini umbhede omanzi?
A umbhede omanzi inqubo ebandakanya ukumisa izinhlayiya eziqinile esimweni esifana noketshezi, ngokuvamile ngokufutha umoya noma igesi ngaphansi kwesiqukathi. Lokhu kudala umbhede wezinhlayiya ezinyakazayo njalo futhi ezinezakhiwo zakho kokubili uketshezi negesi. Imibhede enoketshezi ivame ukusetshenziswa ezinqubweni zezimboni ezifana nokukhiqizwa kwamakhemikhali, ukucwengwa kukawoyela, kanye nokukhiqiza amandla.
Umqondo wokukhipha uketshezi lwaqala ukutholwa ngeminyaka yawo-1930 ngunjiniyela waseBrithani uLewis Fry Richardson, owaqaphela ukuthi isihlabathi sasiziphatha njengoketshezi lapho sipheshulwa umoya. Ngawo-1940, usosayensi waseJalimane uFritz Winkler wasungula i-reactor yokuqala yombhede oketshezi ukuze kukhiqizwe uphethiloli wokwenziwa.
Imibhede efakwe uketshezi inezinzuzo eziningi ngaphezu kwama-reactor emibhede engaguquki evamile, okuhlanganisa ukushisa okuthuthukisiwe nokudluliswa kwenqwaba, ukukhuphuka kwamazinga okusabela, nokulawula okungcono kwezinga lokushisa nokucindezela. Ukuziphatha okufana noketshezi kwezinhlayiya nakho kunciphisa ubungozi bezindawo ezishisayo noma izindawo ezifile, ezingabangela ukusabela okungasebenzi kahle noma okungaphelele.
Idizayini eyisisekelo yombhede onoketshezi iqukethe isitsha noma umkhumbi ogcwele into eqinile, ngokuvamile into eyimbudumbudu njengesihlabathi, i-limestone, noma izinhlayiya ze-catalyst. Umoya noma igesi bese kwethulwa kusukela phansi esitsheni, kwakheka ukugeleza koketshezi oluphakamisa futhi lumise izinhlayiya emoyeni.
Njengoba uketshezi lugeleza embhedeni, lubangela ukuba izinhlayiya zinyakaze futhi zingqubuzane, zenze ukuxuba okuguquguqukayo nomphumela wokuhlanganisa. Lokhu kunyakaza futhi kuveza izinhlayiya endaweni enkulu, okuvumela ukushisa okuphumelelayo nokudluliselwa okukhulu phakathi kwezinhlayiya noketshezi oluzungezile.
Enye yezinzuzo ezibalulekile zemibhede enamanzi amandla ayo okulawula izinga lokushisa lokusabela. Ngokulungisa izinga lokugeleza nezinga lokushisa loketshezi, ama-opharetha angagcina izinga lokushisa elingaguquki kuwo wonke umbhede, avimbele izindawo ezishisayo futhi aqinisekise ukuthi ukusabela kuqhubeka ngesilinganiso esifanele.
Imibhede enoketshezi ivame ukusetshenziswa ekukhiqizeni amakhemikhali, njengokukhiqizwa kwe-ammonia, i-methanol, namanye amakhemikhali e-petrochemical. Zibuye zisetshenziswe ekucubunguleni ukudla kanye nemithi, kanye nokwelapha amanzi angcolile nokunye okulahlwa yizimboni.
Embonini yokuphehla ugesi, imibhede enoketshezi isetshenziswa ekushisweni kwamalahle nezinye izinto ezimbiwa phansi. Le nqubo ihilela ukushisa uphethiloli embhedeni omanzi we-limestone, othintana ne-sulphur dioxide ekhiqizwa ngesikhathi sokusha ukuze yakhe i-calcium sulfate (gypsum). Le nqubo, eyaziwa ngokuthi i-fluidized bed combustion, inciphisa ukukhishwa kwe-sulphur dioxide nezinye izinto ezingcolisayo ezihambisana nezitshalo zamandla ezisetshenziswa ngamalahle ezivamile.
Sengiphetha, imibhede enoketshezi iwubuchwepheshe obusha nobuguquguqukayo obunemisebenzi eminingi yezimboni. Banikeza ukushisa okuthuthukisiwe nokudluliswa kwenqwaba, ukukhuphuka kwamazinga okusabela, nokulawula okungcono kwezinga lokushisa nokucindezela. Asetshenziswa ezimbonini eziningi, okuhlanganisa ukukhiqiza amakhemikhali, ukukhiqiza amandla, ukucubungula ukudla, nokuhlanza amanzi angcolile.
