Mgodi ukukulirakulira chaka chilichonse - mamita 30, malinga ndi malipoti a makampani.
Pamene kuya kumawonjezeka, kufunika kwa mpweya wabwino ndi kuziziritsa kumawonjezekanso, ndipo Howden amadziwa izi kuchokera ku luso lake pogwira ntchito ndi migodi yozama kwambiri ku South Africa.
Howden idakhazikitsidwa mu 1854 ndi James Howden ku Scotland ngati kampani ya uinjiniya wapamadzi ndipo idalowa ku South Africa m'zaka za m'ma 1950 kuti ikwaniritse zosowa za mafakitale a migodi ndi magetsi. Pofika m'ma 1960, kampaniyo idathandizira kukonzekeretsa migodi yagolide yakuzama mdzikolo ndi njira zonse zopumira mpweya ndi kuziziritsira zomwe zimafunikira kuti zitulutse miyala yamtengo wapatali pansi pa nthaka mosamala komanso moyenera.
"Poyamba, mgodi unkangogwiritsa ntchito mpweya wozizira ngati njira yoziziritsira, koma pamene kuzama kwa mgodiwo kunawonjezeka, kuzizira kwa makina kunafunika kuti kulimbitse kutentha komwe kunkakulirakulira mumgodiwo," Teunes Wasserman, mkulu wa dipatimenti ya Howden's Mine Cooling and Compressors, adauza IM.
Migodi yambiri yagolide yozama ku South Africa yayika ma cooler a Freon™ centrifugal pamwamba ndi pansi pa nthaka kuti aziziziritsa anthu ogwira ntchito pansi pa nthaka ndi zida.
Ngakhale kuti zinthu zasintha monga momwe zinalili panopa, makina oyeretsera kutentha a pansi pa nthaka anali ovuta, chifukwa mphamvu yoziziritsira ya makinawo inali yochepa chifukwa cha kutentha ndi kuchuluka kwa mpweya wotuluka, anatero Wasserman. Nthawi yomweyo, ubwino wa madzi m'migodi unachititsa kuti zinthu zotenthetsera zomwe zimagwiritsidwa ntchito m'mafiriji oyambirira a centrifugal ziipire kwambiri.
Pofuna kuthetsa vutoli, migodi inayamba kutulutsa mpweya wozizira kuchokera pamwamba kupita pansi. Ngakhale izi zikuwonjezera mphamvu yozizira, zomangamanga zofunika zimatenga malo mu silo ndipo njirayi imafuna mphamvu komanso mphamvu zambiri.
Pofuna kuthana ndi mavutowa, migodi ikufuna kuwonjezera kuchuluka kwa mpweya wozizira womwe umabweretsedwa pansi kudzera m'madzi ozizira.
Izi zinapangitsa Howden kuyambitsa ma amino screw cooler m'migodi ku South Africa, choyamba mogwirizana ndi ma surface centrifugal cooler omwe alipo kale. Izi zapangitsa kuti pakhale kusintha pang'ono kwa kuchuluka kwa coolant yomwe ingaperekedwe ku migodi yagolide yakuya pansi pa nthaka, zomwe zapangitsa kuti kutentha kwa madzi pamwamba pa nthaka kuchepe kuchokera pa 6-8°C kufika pa 1°C. Mgodiwu ukhoza kugwiritsa ntchito zomangamanga zomwezo za mapaipi a migodi, zomwe zambiri mwa izo zayikidwa kale, pomwe zikuwonjezera kwambiri kuchuluka kwa kuzizira komwe kumaperekedwa ku zigawo zakuya.
Patatha zaka pafupifupi 20 kuchokera pamene WRV 510 inayambitsidwa, Howden, yemwe anali mtsogoleri pa msika, adapanga WRV 510, compressor yayikulu yokhala ndi screw rotor ya 510 mm. Inali imodzi mwa ma screw compressor akuluakulu kwambiri pamsika panthawiyo ndipo inali yofanana ndi kukula kwa chiller module komwe kumafunika kuti kuziziritse migodi yakuya ya ku South Africa.
"Izi zasintha kwambiri chifukwa migodi imatha kukhazikitsa chiller imodzi ya 10-12 MW m'malo mwa chiller zambiri," adatero Wasserman. "Panthawi yomweyo, ammonia ngati refrigerant yobiriwira ndi yoyenera kuphatikiza ma compressor a screw ndi ma plate heat exchangers."
Zinthu zokhudzana ndi ammonia zinakonzedwa m'njira zosiyanasiyana komanso miyezo ya chitetezo cha ammonia m'makampani opanga migodi, ndipo Howden anali ndi gawo lofunika kwambiri pakupanga zinthu. Zasinthidwa ndikuphatikizidwa mu lamulo la South Africa.
Kupambana kumeneku kukuonekera bwino chifukwa cha kukhazikitsidwa kwa mphamvu zoziziritsira za ammonia zoposa 350 MW ndi makampani amigodi aku South Africa, omwe amaonedwa kuti ndi akuluakulu padziko lonse lapansi.
Koma luso la Howden ku South Africa silinathere pamenepo: mu 1985 kampaniyo inawonjezera makina oundana pamwamba pa makina ake oziziritsira omwe anali kukula.
Popeza njira zoziziritsira pamwamba ndi pansi pa nthaka zimaonedwa kuti ndi zokwera mtengo kwambiri, migodi ikufunika njira yatsopano yoziziritsira kuti ipititse patsogolo migodi mpaka kufika pamlingo wozama.
Howden adakhazikitsa fakitale yake yoyamba yopanga ayezi (chitsanzo pansipa) mu 1985 ku EPM (East Rand Proprietary Mine) kum'mawa kwa Johannesburg, komwe kuli mphamvu yoziziritsira yonse ya pafupifupi 40 MW ndi mphamvu ya ayezi ya 4320 t/h.
Maziko a ntchitoyi ndi kupanga ayezi pamwamba ndikuinyamula kudzera mu mgodi kupita ku dambo la ayezi la pansi pa nthaka, komwe madzi ochokera ku dambo la ayezi amayendetsedwa m'malo ozizira apansi pa nthaka kapena kugwiritsidwa ntchito ngati madzi opangira zitsime zokumba. Kenako ayezi wosungunuka amapopedwa kubwerera pamwamba.
Phindu lalikulu la makina opangira ayezi awa ndi kuchepetsa ndalama zopopera madzi, zomwe zimachepetsa ndalama zogwirira ntchito zokhudzana ndi makina ozizira pamwamba pa madzi ndi pafupifupi 75-80%. Izi zimadalira "mphamvu yozizira yomwe imasungidwa mu kusintha kwa madzi," adatero Wasserman, pofotokoza kuti 1kg/s ya ayezi ili ndi mphamvu yoziziritsira yofanana ndi 4.5-5kg/s ya madzi ozizira.
Chifukwa cha "kukonza bwino malo", damu la pansi pa nthaka likhoza kusungidwa pa 2-5°C kuti liwongolere kutentha kwa malo oziziritsira mpweya pansi pa nthaka, komanso kuwonjezera mphamvu yoziziritsira.
Ubwino wina wa kufunika kwa malo opangira magetsi a ayezi ku South Africa, dziko lodziwika ndi gridi yake yamagetsi yosakhazikika, ndi kuthekera kwa makinawa kugwiritsidwa ntchito ngati njira yosungira kutentha, komwe ayezi amapangidwa ndikusonkhanitsidwa m'madamu a ayezi apansi pa nthaka komanso nthawi yomwe madzi amafika pachimake.
Phindu lomalizali lapangitsa kuti pakhale mgwirizano wamakampani wothandizidwa ndi Eskom pomwe Howden ikufufuza momwe opanga ayezi amagwiritsidwira ntchito kuti achepetse kufunikira kwa magetsi, ndi mayeso ku Mponeng ndi Moab Hotsong, migodi yakuya kwambiri padziko lonse lapansi.
"Tinazizira damu usiku (titamaliza kugwira ntchito) ndipo tinagwiritsa ntchito madzi ndi ayezi wosungunuka ngati gwero loziziritsira mgodi nthawi yomwe ntchito ikupitirira," Wasserman anafotokoza. "Magawo oziziritsira madzi amazimitsidwa nthawi yomwe ntchito ikupitirira, zomwe zimachepetsa katundu pa gridi."
Izi zinapangitsa kuti pakhale makina oyeretsera ayezi ku Mponeng, komwe Howden anamaliza ntchitoyo kuphatikizapo zida zapakhomo, zamagetsi ndi zamakina za makina oyeretsera ayezi a 12 MW, 120 t/h.
Zowonjezera zaposachedwa pa njira yayikulu yoziziritsira ya Mponeng zikuphatikizapo ayezi wofewa, madzi ozizira pamwamba, zoziziritsira mpweya pamwamba (BACs) ndi makina oziziritsira pansi pa nthaka, kupezeka kwa mchere wosungunuka ndi ma chloride m'madzi a migodi panthawi yogwira ntchito.
Iye akutero chifukwa cha luso la South Africa komanso kuyang'ana kwambiri pa mayankho, osati zinthu zokha, zomwe zikupitiriza kusintha makina oziziritsira padziko lonse lapansi.
Monga momwe Wasserman adanenera, pamene migodi yambiri ikukulirakulira m'migodi, n'zosavuta kuwona mayankho ngati awa omwe amapezeka m'madera ena a dziko lapansi.
Meinhardt anati: “Howden yakhala ikutumiza ukadaulo wake wozizira kwambiri ku South Africa kwa zaka zambiri. Mwachitsanzo, tidapereka njira zoziziritsira ku migodi yagolide yapansi panthaka ku Nevada m'zaka za m'ma 1990.
"Ukadaulo wosangalatsa womwe umagwiritsidwa ntchito m'migodi ina ya ku South Africa ndi kusunga ayezi wotentha kuti azitha kunyamula katundu - mphamvu yotenthetsera imasungidwa m'madamu akuluakulu a ayezi. Iye amapangidwa nthawi ya ntchito yochuluka ndipo amagwiritsidwa ntchito nthawi ya ntchito yochuluka," adatero. "Mwachikhalidwe, mafiriji amapangidwa kuti azitentha kwambiri komwe kumatha kufika maola atatu patsiku m'miyezi yachilimwe. Komabe, ngati muli ndi mphamvu yosungira mphamvu yoziziritsira, mutha kuchepetsa mphamvuyo."
"Ngati muli ndi dongosolo lokhala ndi chiwongola dzanja chapamwamba kwambiri ndipo mukufuna kukweza mitengo kukhala yotsika mtengo nthawi yomwe si nthawi yotanganidwa, njira zopangira ayezi izi zitha kukhala bizinesi yolimba," adatero. "Ndalama zoyambira za fakitaleyi zitha kuchepetsa ndalama zogwirira ntchito."
Pa nthawi yomweyo, BAC, yomwe yakhala ikugwiritsidwa ntchito m'migodi ya ku South Africa kwa zaka zambiri, ikuyamba kutchuka kwambiri padziko lonse lapansi.
Poyerekeza ndi mapangidwe achikhalidwe a BAC, mibadwo yaposachedwa ya BACs ili ndi mphamvu yotenthetsera kwambiri kuposa yakale, kuchepetsa malire a kutentha kwa mpweya m'migodi komanso kuchepa kwa malo. Amaphatikizanso gawo loziziritsa-pofuna (CoD) mu nsanja ya Howden Ventsim CONTROL, yomwe imasintha yokha kutentha kwa mpweya wa kolala kuti igwirizane ndi zosowa za pansi pa nthaka.
Chaka chathachi, Howden yapereka ma BAC atatu atsopano kwa makasitomala ku Brazil ndi Burkina Faso.
Kampaniyo imathanso kupanga njira zothetsera mavuto; chitsanzo chaposachedwa ndi kukhazikitsa 'kwapadera' kwa zoziziritsira za BAC ammonia za OZ Minerals ku mgodi wa Carrapateena ku South Australia.
“Howden anaika ma condenser ouma ndi ma compressor a ammonia a Howden ndi ma closed loop dry air cooler ku Australia popanda madzi,” anatero Wasserman ponena za kukhazikitsa. “Popeza kuti iyi ndi njira yokhazikika osati ma open spray cooler omwe amaikidwa m'madzi, ma cooler awa apangidwa kuti azigwira ntchito bwino kwambiri.”
Kampaniyo pakadali pano ikuyesa njira yowunikira nthawi yogwira ntchito ya fakitale ya BAC ya 8 MW yomwe ili m'mphepete mwa nyanja (yomwe ili pachithunzi pansipa) yopangidwa ndikumangidwa ku mgodi wa Yaramoko Fortuna Silver (womwe kale unkatchedwa Roxgold) ku Burkina Faso.
Dongosololi, lomwe limayang'aniridwa ndi fakitale ya Howden ku Johannesburg, limalola kampaniyo kupereka upangiri pakusintha magwiridwe antchito ndi kukonza kuti fakitaleyo igwire ntchito bwino. Gawo la BAC ku Caraiba migodi ku Ero Copper, Brazil lapangidwanso kuti ligwiritse ntchito izi.
Pulatifomu ya Total Mine Ventilation Solutions (TMVS) ikupitilizabe kumanga ubale wokhazikika komanso wowonjezera phindu ndipo kampaniyo idzayambitsa maphunziro awiri ofunikira okhudza momwe Ventilation On Demand (VoD) ikuyendera mdziko muno mu 2021.
Pamalire a dziko la Zimbabwe, kampaniyo ikugwira ntchito yokonza pulojekiti yomwe ingathandize kuti zitseko zodziyimira zokha zizigwiritsidwa ntchito pa intaneti, zomwe zimathandiza kuti zitsekozo zitsegulidwe nthawi zosiyanasiyana komanso kuti mpweya uzizire mokwanira kutengera zosowa za galimotoyo.
Kukonza ukadaulo kumeneku, pogwiritsa ntchito zomangamanga zomwe zilipo kale za migodi komanso magwero a deta omwe alipo kale, kudzakhala gawo lofunika kwambiri la zinthu zamtsogolo za Howden.
Chidziwitso cha Howden ku South Africa: Phunzirani momwe mungapangire njira zoziziritsira kuti muthane ndi vuto la madzi otsika m'migodi yake yagolide, momwe mungapangire njira zogwiritsira ntchito mphamvu moyenera momwe mungathere kuti mupewe mavuto a gridi, komanso momwe mungakwaniritsire zina mwazofunikira kwambiri pa kutentha ndi thanzi la ntchito padziko lonse lapansi. Malamulo - apitilizabe kupindulitsa migodi padziko lonse lapansi.
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