Imayini iya ngokujula minyaka yonke - 30 m, ngokwemibiko yemboni.
Njengoba ukujula kukhula, siyanda nesidingo sokungenisa umoya nokupholisa, futhi uHowden ukwazi lokhu ngokuhlangenwe nakho kokusebenza nezimayini ezijulile eNingizimu Afrika.
I-Howden yasungulwa ngo-1854 nguJames Howden eScotland njengenkampani yobunjiniyela basolwandle futhi yangena eNingizimu Afrika ngeminyaka yawo-1950 ukuze ihlinzekele izidingo zezimboni zezimayini kanye namandla.Ngawo-1960, inkampani yasiza ekuhlomiseni izimayini zegolide ezijulile zezwe ngazo zonke izinhlelo zokungena komoya kanye nokupholisa okudingekayo ukuze kukhishwe amamayela ensimbi ngaphansi komhlaba ngokuphepha nangempumelelo.
“Ekuqaleni, imayini ibisebenzisa kuphela umoya wokupholisa njengendlela yokupholisa, kodwa njengoba ukujula kwezimayini kwanda, ukupholisa ngemishini kwadingeka ukuze kunxephezele umthamo wokushisa okhulayo emayini,” uTeunes Wasserman, inhloko yophiko lweHowden's Mine Cooling and Compressors, etshela i-IM.
Izimayini eziningi zegolide ezijulile eNingizimu Afrika zifake ama-Freon™ centrifugal coolers ngaphezulu nangaphansi komhlaba ukuze ahlinzeke ngokupholisa okudingekayo kubasebenzi abangaphansi komhlaba kanye nemishini.
Naphezu kokuba ngcono kwesimo esikhona, uhlelo lokukhipha ukushisa lomshini ongaphansi komhlaba lubonakale luyinkinga, njengoba amandla okupholisa umshini alinganiselwe izinga lokushisa kanye nenani lomoya wokukhipha umoya otholakalayo, kusho u-Wasserman.Ngesikhathi esifanayo, ikhwalithi yamanzi asezimayini ibangele ukungcoliswa okunamandla kwezishintshi zokushisa zegobolondo neshubhu ezisetshenziswa kulawa ma-cold centrifugal asekuqaleni.
Ukuze kuxazululwe le nkinga, izimayini zaqala ukumpompa umoya obandayo usuka phezulu uye phansi.Nakuba lokhu kwandisa umthamo wokupholisa, ingqalasizinda edingekayo ithatha indawo esiseleni futhi inqubo idinga amandla namandla.
Ukubhekana nalezi zinkinga, izimayini zifuna ukukhulisa inani lomoya obandayo olethwa phansi ngamayunithi amanzi abandayo.
Lokhu kugqugquzele u-Howden ukuthi ethule ama-amino screw cooler ezimayini eNingizimu Afrika, okokuqala ngokuhambisana ngemva kwama-cooler e-surface centrifugal akhona.Lokhu kuholele ekushintsheni kwesinyathelo senani lokupholisa okungalethwa kulezi zimayini zegolide ezijulile ezingaphansi komhlaba, okuholela ekwehleni kwezinga lokushisa lamanzi angaphezulu eliphakathi ukusuka ku-6-8°C kuya ku-1°C.Imayini ingasebenzisa ingqalasizinda yepayipi lezimayini efanayo, iningi lazo esivele lifakiwe, kuyilapho ikhulisa kakhulu inani lokupholisa elilethwa ezingqimbeni ezijulile.
Cishe eminyakeni engu-20 ngemva kokwethulwa kwe-WRV 510, u-Howden, umdlali wemakethe ohamba phambili kulo mkhakha, wasungula i-WRV 510, i-screw compressor enkulu ene-rotor engu-510 mm.Kwakungenye yemishini emikhulu yokucindezela isikulufu emakethe ngaleso sikhathi futhi ihambisana nosayizi wemojuli ye-chiller edingekayo ukupholisa lezo zimayini ezijulile zaseNingizimu Afrika.
“Lokhu kuyawushintsha umdlalo ngoba izimayini zingafaka i-chiller eyodwa ye-10-12 MW esikhundleni senqwaba yama-chillers,” kusho u-Wasserman."Phakathi kwesikhathi esifanayo, i-ammonia njengesiqandisi esiluhlaza ifaneleka kahle ekuhlanganiseni ama-screw compressor kanye nezishintshi zokushisa zamapuleti."
Ukucatshangelwa kwe-ammonia kwenziwa ngokusemthethweni emibhalweni kanye namazinga okuphepha e-ammonia embonini yezimayini, kanti i-Howden idlala indima ebalulekile enqubweni yokuklama.Abuyekeziwe futhi afakwa emthethweni waseNingizimu Afrika.
Le mpumelelo ifakazelwa ukufakwa kwamandla angaphezu kwama-350 MW esiqandisini se-ammonia yimboni yezimayini yaseNingizimu Afrika, ethathwa njengenkulu emhlabeni.
Kodwa ukuqamba okusha kwe-Howden eNingizimu Afrika akuphelelanga lapho: ngo-1985 inkampani yengeza umshini weqhwa ongaphezu kohlobo olukhulayo lwezipholile zasezimayini.
Njengoba izinketho zokupholisa ngaphezulu nangaphansi komhlaba zandiswa noma kuthathwa ngokuthi zibiza kakhulu, izimayini zidinga isisombululo esisha sokupholisa ukuze kuqhutshekwe nokunwetshwa kwezimayini ziye emazingeni ajulile.
I-Howden yafaka isikhungo sayo sokuqala sokwenza iqhwa (isibonelo ngezansi) ngo-1985 e-EPM (East Rand Proprietary Mine) empumalanga yeGoli, enamandla okupholisa aphelele angaba ngu-40 MW kanye nomthamo weqhwa ongu-4320 t/h.
Isisekelo salo msebenzi ukwakheka kweqhwa phezulu bese lithuthwa emayini liye edamini leqhwa elingaphansi komhlaba, lapho amanzi asuka edamini leqhwa abe esesakazwa eziteshini zokupholisa ngaphansi komhlaba noma asetshenziswe njengamanzi enqubo yokumba imithombo.Iqhwa elincibilikile libe seliphindiselwa phezulu.
Inzuzo enkulu yalolu hlelo lwe-icemaker yizindleko zokumpompa ezincishisiwe, ezinciphisa izindleko zokusebenza ezihambisana nezinhlelo zamanzi abandayo angaphezulu cishe ngo-75-80%.Kwehlela “kumandla okupholisa angokwemvelo agcinwe ezinguqulweni zesigaba samanzi,” kusho u-Wasserman, echaza ukuthi i-1kg/s yeqhwa inamandla okupholisa afana no-4.5-5kg/s wamanzi ayiqhwa.
Ngenxa “yokusebenza kahle kokuma okuphakeme”, idamu elingaphansi komhlaba lingagcinwa liku-2-5°C ukuze kuthuthukiswe ukusebenza okushisayo kwesiteshi sokupholisa umoya esingaphansi komhlaba, futhi kwandise umthamo wokupholisa.
Enye inzuzo yokubaluleka okuthile kwesikhungo sokuphehla amandla eqhwa eNingizimu Afrika, izwe elaziwa ngegridi yaso kagesi engazinzile, ikhono lohlelo lokusebenzisa indlela yokugcina ukushisa, lapho kwakhiwa khona iqhwa futhi liqoqwe emadamini eqhwa angaphansi komhlaba kanye nangezikhathi eziphakeme kakhulu..
Umhlomulo wokugcina uholele ekuthuthukisweni kwephrojekthi yobambiswano lwemboni esekelwa u-Eskom lapho i-Howden iphenya ngokusetshenziswa kwezikhiqizi zeqhwa ukuze kwehliswe isidingo sikagesi esiphezulu, ngamacala okuhlola e-Mponeng nase-Moab Hotsong, izimayini ezijule kakhulu emhlabeni.
"Saqandisa idamu ebusuku (ngemuva kwamahora) futhi sasebenzisa amanzi kanye neqhwa njengendlela yokupholisa imayini ngesikhathi sokusebenza kanzima," kuchaza uWasserman."Amayunithi okupholisa ayisisekelo ayacishwa ngezikhathi eziphakeme kakhulu, okunciphisa umthwalo kugridi."
Lokhu kuholele ekuthuthukisweni komshini weqhwa ojikajikayo eMponeng, lapho u-Howden aqeda khona umsebenzi ohlanganisa i-civil, ugesi kanye nemishini yemishini yomshini weqhwa ongu-12 MW, 120 t/h.
Ukwengezwa kwakamuva esu lokupholisa eliyinhloko likaMponeng zifaka iqhwa elithambile, amanzi abandayo angaphezulu, ama-surface air cooler (BACs) kanye nesistimu yokupholisa engaphansi komhlaba.ukuba khona emanzini asezimayini ukugxila okuphezulu kosawoti nama-chloride ancibilikile ngesikhathi somsebenzi.
Ingcebo yesipiliyoni saseNingizimu Afrika kanye nokugxila ezisombululweni, hhayi emikhiqizweni kuphela, iyaqhubeka nokuguqula izinhlelo zesiqandisi emhlabeni wonke, usho kanje.
Njengoba u-Wasserman eshilo, njengoba ziya ngokwanda izimayini zingena zijula ​​nendawo eningi ezimayini, kulula ukubona izixazululo ezinjengalezi ezitholakala kwezinye izingxenye zomhlaba.
UMeinhardt uthe: “I-Howden isineminyaka engamashumi eminyaka ithumela ubuchwepheshe bokupholisa imayini ejulile eNingizimu Afrika.Isibonelo, sinikeze izixazululo zokupholisa imayini ezimayini zegolide ezingaphansi komhlaba e-Nevada emuva ngeminyaka yawo-1990.
“Ubuchwepheshe obuthakaselayo obusetshenziswa kwezinye izimayini zaseNingizimu Afrika ukugcina iqhwa elishisayo ukuze lidlulise umthwalo - amandla ashisayo agcinwa emadamini amakhulu eqhwa.Iqhwa likhiqizwa ngezikhathi eziphakeme futhi lisetshenziswa ngezikhathi eziphakeme kakhulu, ”kusho yena.“Ngokwesiko, iziqandisi zenzelwe izinga lokushisa eliphezulu elingafinyelela amahora amathathu ngosuku phakathi nezinyanga zasehlobo.Kodwa-ke, uma unamandla okugcina amandla okupholisa, ungawehlisa lawo mandla.”
"Uma unohlelo olunezinga eliphakeme kakhulu futhi ufuna ukuthuthukela emazingeni ashibhile ngezikhathi ezingabizi kakhulu, lezi zixazululo zokwenza iqhwa zingenza ibhizinisi eliqinile," esho."Imali yokuqala yesimboni inganciphisa izindleko zokusebenza."
Ngaso leso sikhathi, i-BAC, osekuphele amashumi eminyaka isetshenziswa ezimayini zaseNingizimu Afrika, izuza ukubaluleka okukhulu emhlabeni jikelele.
Uma kuqhathaniswa nemiklamo ye-BAC evamile, isizukulwane sakamuva sama-BAC sinokusebenza okushisayo okuphezulu kunangaphambili, imikhawulo ephansi yokushisa komoya yemayini kanye nendawo encane.Baphinde bahlanganise imojuli yokupholisa-pholisa (i-CoD) endaweni yesikhulumi se-Howden Ventsim CONTROL, elungisa ngokuzenzakalelayo izinga lokushisa lomoya wekholomu ukuze lifane nezidingo ezingaphansi komhlaba.
Ngonyaka odlule, u-Howden ulethe ama-BAC amathathu esizukulwane esisha kumakhasimende aseBrazil naseBurkina Faso.
Le nkampani iyakwazi futhi ukukhiqiza izixazululo ezenziwe ngokwezifiso zezimo ezinzima zokusebenza;isibonelo sakamuva ukufakwa 'okuyingqayizivele' kwezipholile ze-BAC ammonia ze-OZ Minerals emayini yase-Carrapateena eNingizimu ye-Australia.
"I-Howden ifake ama-condensers omile ane-Howden ammonia compressor kanye nama-cooler air dry dry e-Australia lapho engekho amanzi," kusho u-Wasserman mayelana nokufakwa.“Ngenxa yokuthi lokhu ukufakwa 'komile' futhi akuzona izifutho ezivulekile ezifakwe ezinhlelweni zamanzi, lezi zipholile zenzelwe ukusebenza kahle kakhulu."
Le nkampani njengamanje ihlola isixazululo sokuqapha isikhathi esengeziwe semboni ye-BAC esogwini engu-8 MW (esithombeni ngezansi) eklanywe futhi yakhiwa emayini ye-Yaramoko Fortuna Silver (eyayiyi-Roxgold) eBurkina Faso.
Uhlelo, olulawulwa yifekthri yase-Howden eGoli, luvumela inkampani ukuthi yeluleke mayelana nentuthuko engase ibe khona kanye nokunakekelwa okufanele ukuze igcine imboni isebenza ngendlela yayo yonke.Iyunithi ye-BAC endaweni yezimayini yase-Caraiba e-Ero Copper, e-Brazil nayo yakhelwe ukusebenzisa lesi sici.
Inkundla yeTotal Mine Ventilation Solutions (TMVS) iyaqhubeka nokwakha ubudlelwano obuqhubekayo bevalue-added futhi inkampani izokwethula izifundo ezimbili ezingenzeka zeVentilation On Demand (VoD) ezweni ngo-2021.
Khona lapho emngceleni weZimbabwe, inkampani le isebenzela uhlelo oluzakwenza ukuthi i-video-on-demand ivuleke emigodini engaphansi komhlaba, ivumele ukuthi ivuleke ngezikhathi ezitshiyeneyo futhi inikeze umoya opholisayo oneleyo kusiya ngezidingo ezithile zemota.
Lokhu kuthuthukiswa kobuchwepheshe, kusetshenziswa ingqalasizinda ekhona yezimayini kanye nemithombo yedatha engekho eshalofini, kuzoba yingxenye ebalulekile yemikhiqizo yesikhathi esizayo ye-Howden.
Ulwazi lwase-Howden eNingizimu Afrika: Funda indlela yokuklama izixazululo zokupholisa ukuze ubhekane nezinga eliphansi lamanzi ezimayini zayo zegolide ezijulile, indlela yokwenza izixazululo ngendlela eyonga ugesi ngangokunokwenzeka ukuze kugwenywe izinkinga zegridi, kanye nendlela yokuhlangabezana nezinye zezidingo zekhwalithi yomoya eziqinile.izinga lokushisa kanye nezidingo zempilo yomsebenzi emhlabeni wonke Umthethonqubo - uzoqhubeka nokukhokhela izimayini emhlabeni jikelele.
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