Raporo z’inganda zivuga ko ikirombe kigenda kirushaho kuba kirekire buri mwaka - metero 30.
Uko ubujyakuzimu bwiyongera, ni nako gukenera guhumeka no gukonjesha bigenda byiyongera, kandi Howden arabizi akurikije ubunararibonye afite mu gukorana n'ibirombe birebire cyane muri Afurika y'Epfo.
Howden yashinzwe mu 1854 na James Howden muri Ecosse nk'ikigo cy'ubuhanga mu by'amazi, yinjiye muri Afurika y'Epfo mu myaka ya 1950 kugira ngo ikorere ibyo inganda z'ubucukuzi bw'amabuye y'agaciro n'amashanyarazi zikeneye. Mu myaka ya 1960, iyi sosiyete yafashije mu guha ibikoresho byose byo mu birombe bya zahabu byo mu gihugu ibikoresho byo guhumeka no gukonjesha byari bikenewe kugira ngo icukure amabuye y'agaciro mu butaka mu buryo bwizewe kandi bunoze.
“Mbere, ikirombe cyakoreshaga umwuka nk'uburyo bwo gukonjesha gusa, ariko uko ubujyakuzimu bw'ubucukuzi bwiyongeraga, hakenewe gukonjesha hakoreshejwe imashini kugira ngo habeho ubushyuhe bwinshi bwari buri kwiyongera mu kirombe,” Teunes Wasserman, umuyobozi w’ishami rya Howden rishinzwe gukonjesha no gukamura ibikomoka kuri kompanyi, yabwiye IM.
Ibirombe byinshi bya zahabu byimbitse muri Afurika y'Epfo byashyizeho ibyuma bikonjesha bya Freon™ hejuru no munsi y'ubutaka kugira ngo bitange ubukonje bukenewe ku bakozi bo munsi y'ubutaka n'ibikoresho.
Nubwo ibintu byari bimeze neza, uburyo bwo gukwirakwiza ubushyuhe bw’imashini yo munsi y’ubutaka bwagaragaye ko ari ikibazo, kuko ubushobozi bwo gukonjesha bw’imashini bwari bugabanijwe n’ubushyuhe n’umuvuduko w’umwuka uturuka mu kirere, nk’uko Wasserman yabitangaje. Muri icyo gihe, ubwiza bw’amazi yo mu birombe bwateje umwanda ukomeye ku byuma bihindura ubushyuhe byakoreshejwe muri ibyo byuma bikonjesha bya mbere.
Kugira ngo iki kibazo gikemuke, ibirombe byatangiye gukurura umwuka ukonje uva hejuru ujya hasi. Nubwo ibi byongera ubushobozi bwo gukonjesha, ibikorwa remezo bikenewe bifata umwanya muri silo kandi inzira ikoresha ingufu n'ingufu nyinshi.
Kugira ngo ibi bibazo bikemuke, ibirombe birashaka kongera ingano y'umwuka ukonje uzanwa mu butaka binyuze mu byuma bikonjesha.
Ibi byatumye Howden ashyiraho uburyo bwo gukonjesha amino screw mu birombe byo muri Afurika y'Epfo, bwa mbere bugakurikira ubwo gukonjesha buriho hejuru. Ibi byatumye habaho impinduka mu ntambwe mu mubare w'ibikoresho bikonjesha bishobora gutangwa muri ibyo birombe bya zahabu biri munsi y'ubutaka, bituma ubushyuhe bw'amazi yo hejuru bugabanuka kuva kuri 6-8°C kugera kuri 1°C. Iki kirombe gishobora gukoresha ibikorwa remezo bimwe by'imiyoboro y'ikirombe, byinshi muri byo bikaba byarashyizweho, mu gihe cyongera cyane ingano y'ibikoresho bikonjesha bigezwa mu bice biri hejuru.
Nyuma y'imyaka igera kuri 20 hashyizweho WRV 510, Howden, umukinnyi ukomeye ku isoko, yakoze WRV 510, compressor nini ifite rotor ya mm 510. Yari imwe muri compressor nini cyane ku isoko icyo gihe kandi yari ijyanye n'ingano ya module ikoreshwa mu gukonjesha yari ikenewe kugira ngo ikonjeshe ibyo birombe byo mu mazi byimbitse byo muri Afurika y'Epfo.
Wasserman yagize ati: “Ibi ni impinduka kuko ibirombe bishobora gushyiraho icyuma kimwe cya MW 10-12 aho gushyiraho icyuma kinini cya firigo.” Muri icyo gihe, ammonia nk'icyuma gikonjesha icyatsi kibisi ikwiriye cyane mu guhuza compressors za screw na plate heating.”
Ibipimo bya amoniya byashyizweho mu buryo bwemewe n'amategeko agenga umutekano wa amoniya mu nganda z'ubucukuzi bw'amabuye y'agaciro, aho Howden yagize uruhare runini mu gushushanya. Byavuguruwe kandi byinjiye mu mategeko ya Afurika y'Epfo.
Iyi ntsinzi igaragazwa n’inganda zicukura amabuye y’agaciro zo muri Afurika y’Epfo zishyiramo megawati zisaga 350 z’ubukonje bwa ammonia, zifatwa nk’izinini ku isi.
Ariko udushya twa Howden muri Afurika y'Epfo ntitwahagaze aho: mu 1985 isosiyete yongereye imashini ikora urubura ku ruganda rwayo rukora ibintu bikonjesha mu birombe byayo.
Kubera ko uburyo bwo gukonjesha hejuru no munsi y’ubutaka bukoreshwa cyane cyangwa bufatwa nk’aho buhenze cyane, ibirombe bikeneye uburyo bushya bwo gukonjesha kugira ngo ubucukuzi burusheho kwaguka mu buryo bwimbitse.
Howden yashyizeho uruganda rwa mbere rukora urubura (urugero ruri hepfo) mu 1985 kuri EPM (East Rand Proprietary Mine) mu burasirazuba bwa Johannesburg, rufite ubushobozi bwo gukonjesha bwa MW 40 n'ubushobozi bwo gukonjesha bwa 4320 t / h.
Ishingiro ry'igikorwa ni ukubaka urubura hejuru y'ubutaka rukarutwara runyuze mu kirombe rujya mu rugomero rw'urubura rwo munsi y'ubutaka, aho amazi ava mu rugomero rw'urubura anyura mu bigega bikonjesha munsi y'ubutaka cyangwa agakoreshwa nk'amazi yo gutunganya amariba yo gucukura. Urubura rwashongeshejwe rugasubizwa hejuru y'ubutaka.
Inyungu nyamukuru y'iyi sisitemu yo gukora urubura ni ukugabanya ikiguzi cyo kuvoma, bigabanya ikiguzi cyo gukoresha amazi akonje ku buso ku kigero cya 75-80%. Biterwa n'"ingufu zo gukonjesha zibikwa mu gihe cy'impinduka z'amazi," nk'uko Wasserman yabitangaje, asobanura ko 1kg/s y'urubura ifite ubushobozi bwo gukonjesha nk'ubwa 4.5-5kg/s bw'amazi akonje.
Bitewe n' "ubushobozi bwo gushyira ibintu mu mwanya mwiza cyane", urugomero rwo munsi y'ubutaka rushobora kugumana ubushyuhe kuri 2-5°C kugira ngo hongerwe imikorere y'ubushyuhe bw'aho icyuma gikonjesha umwuka kiri munsi y'ubutaka, byongere ubushobozi bwo gukonjesha.
Indi nyungu y'akamaro k'uruganda rw'amashanyarazi rukora urubura muri Afurika y'Epfo, igihugu kizwiho amashanyarazi adahindagurika, ni ubushobozi bw'uru ruganda bwo gukoresha nk'uburyo bwo kubika ubushyuhe, aho urubura ruremwa kandi rugakusanyirizwa mu ngomero z'urubura zo munsi y'ubutaka no mu bihe by'ubushyuhe bwinshi.
Inyungu ya nyuma yatumye habaho umushinga w’ubufatanye mu nganda uterwa inkunga na Eskom, aho Howden irimo gukora iperereza ku ikoreshwa ry’ibikoresho bicukura urubura mu kugabanya ikoreshwa ry’amashanyarazi mu rwego rwo hejuru, aho ibizamini bikorerwa muri Mponeng na Moab Hotsong, ibirombe birebire cyane byo munsi y’ubutaka ku isi.
Wasserman yasobanuye ati: “Twakonjesheje urugomero nijoro (nyuma y’amasaha y’akazi) kandi dukoresha amazi n’urubura rwashongeshejwe nk’isoko yo gukonjesha ibirombe mu gihe cy’akazi kenshi.” “Ibyuma byo gukonjesha birinda kuzimwa mu gihe cy’akazi kenshi, ibyo bikagabanya umutwaro ku muyoboro w’amashanyarazi.”
Ibi byatumye habaho imashini ikora urubura i Mponeng, aho Howden yarangije imirimo irimo ibikoresho bya gisivili, amashanyarazi n'imashini ya kaninike ku imashini ikora urubura ya megawati 12 na toni 120 ku isaha.
Inyongera ziherutse kugerwaho ku ngamba z’ingenzi za Mponeng zo gukonjesha zirimo urubura rworoshye, amazi akonjesha hejuru, ibikoresho bikonjesha hejuru (BACs) n’uburyo bwo gukonjesha munsi y’ubutaka, kuba mu mazi yacukuwe hari umunyu mwinshi washongeshejwe na chloride mu gihe cy’akazi.
Avuga ko ubunararibonye bwinshi bwa Afurika y'Epfo n'uburyo yibanda ku bisubizo, atari ku bicuruzwa gusa, bikomeje guhindura uburyo bwo gukonjesha hirya no hino ku isi.
Nkuko Wasserman yabivuze, uko ibirombe byinshi bigenda byiyongera mu birombe, biroroshye kubona ibisubizo nk'ibi biboneka mu bindi bice by'isi.
Meinhardt yagize ati: “Howden imaze imyaka ibarirwa muri za mirongo yohereza ikoranabuhanga ryayo ryo gukonjesha ibirombe muri Afurika y'Epfo. Urugero, twatanze ibikoresho byo gukonjesha ibirombe bya zahabu byo munsi y'ubutaka muri Nevada mu myaka ya 1990.
Yagize ati: “Ikoranabuhanga rishimishije rikoreshwa mu birombe bimwe na bimwe byo muri Afurika y’Epfo ni ugubika urubura rushyushye kugira ngo rwohereze imizigo – ingufu z’ubushyuhe zibikwa mu ngomero nini z’urubura. Urubura rukorwa mu masaha y’ubushyuhe kandi rukoreshwa mu masaha y’ubushyuhe.” “Ubusanzwe, ibikoresho byo gukonjesha byagenewe ubushyuhe ntarengwa bushobora kugera ku masaha atatu ku munsi mu gihe cy’izuba. Ariko, niba ufite ubushobozi bwo kubika ingufu zo gukonjesha, ushobora kugabanya ubwo bushobozi.”
Yagize ati: “Niba ufite gahunda ifite igipimo cyo hejuru cyane kandi ukaba ushaka kuzamuka ukagera ku giciro gito mu bihe bitari iby’umuvuduko, ibi bisubizo byo gukora urubura bishobora kuba ikimenyetso gikomeye cy’ubucuruzi.” “Imari y’ibanze y’uruganda ishobora kugabanya ikiguzi cyo gukora.”
Muri icyo gihe, BAC, imaze imyaka ibarirwa muri za mirongo ikoreshwa mu birombe byo muri Afurika y'Epfo, irimo kwiyongera ku rwego rw'isi.
Ugereranyije n'imiterere gakondo ya BAC, ubwoko bugezweho bwa BAC bufite ubushobozi bwo gukoresha ubushyuhe bwinshi kurusha ubwa mbere, bugabanya ubushyuhe bw'umwuka mu birombe kandi bufite aho bugarukira hato. Bunashyiramo module ya cooling-on-demand (CoD) muri platform ya Howden Ventsim CONTROL, ihindura ubushyuhe bw'umwuka mu ijosi kugira ngo buhuze n'ibikenewe munsi y'ubutaka.
Mu mwaka ushize, Howden yatanze imiti itatu mishya ya BAC ku bakiriya bo muri Brezili na Burkina Faso.
Iyi kompanyi kandi ishobora gukora ibisubizo byihariye ku mikorere igoye; urugero ruherutse ni ugushyiramo "imyuka idasanzwe" ya BAC ammonia cooler kuri OZ Minerals mu kirombe cya Carrapateena muri Ositaraliya y'Amajyepfo.
“Howden yashyizeho ibikoresho byumye bifite ibyuma bikonjesha bya Howden ammonia na ibyuma bikonjesha umwuka bifunganye muri Ositaraliya mu gihe nta mazi ahari,” Wasserman yavuze ku bijyanye no gushyiraho. “Bitewe n’uko iyi ari ibyuma byumye kandi atari ibyuma bikonjesha bifunguye byashyizwe mu buryo bw’amazi, ibi bikoresho bikonjesha byagenewe gukora neza cyane.”
Ubu iyi kompanyi irimo kugerageza uburyo bwo gukurikirana igihe ntarengwa cy’uruganda rwa BAC rufite ingufu za MW 8 ku nkombe (rugaragara ku ifoto iri hepfo) rwakozwe kandi rwubakwa mu kirombe cya Yaramoko Fortuna Silver (cyahoze ari Roxgold) muri Burkina Faso.
Ubu buryo, bugenzurwa n'uruganda rwa Howden ruri i Johannesburg, bwemerera isosiyete gutanga inama ku kunoza imikorere no kubungabunga uruganda kugira ngo rukomeze gukora neza. Ishami rya BAC riri mu nyubako y'ubucukuzi bwa Caraiba muri Ero Copper, muri Brezili naryo ryagenewe gukoresha ubu buryo.
Porogaramu ya Total Mine Ventilation Solutions (TMVS) ikomeje kubaka umubano urambye n’inyongeramusaruro, kandi iyi sosiyete izatangiza inyigo ebyiri zo kugenzura niba Ventilation On Demand (VoD) zishoboka mu gihugu mu 2021.
Ku mupaka wa Zimbabwe, iyi kompanyi irimo gukora umushinga uzatuma inzugi zikora amashusho ku buryo bworoshye mu birombe byo munsi y’ubutaka, bityo zikabasha gufunguka mu bihe bitandukanye no gutanga ingano ikwiye y’umwuka ukonje bitewe n’ibyo imodoka ikeneye.
Iri terambere ry'ikoranabuhanga, rikoresheje ibikorwa remezo by'ubucukuzi bw'amabuye y'agaciro bihari n'amakuru aboneka ku isoko, rizaba igice cy'ingenzi cy'ibicuruzwa bya Howden mu gihe kizaza.
Ubunararibonye bwa Howden muri Afurika y'Epfo: Menya uburyo bwo gushushanya ibisubizo byo gukonjesha kugira ngo uhangane n'ubuziranenge bw'amazi mu birombe byayo binini bya zahabu, uburyo bwo gukoresha ingufu mu buryo bushoboka kugira ngo wirinde ibibazo by'amashanyarazi, n'uburyo bwo kubahiriza bimwe mu bisabwa cyane mu buziranenge bw'umwuka. Ibisabwa ku bushyuhe n'ubuzima bw'akazi ku isi yose Amabwiriza - azakomeza gutanga umusaruro ku birombe hirya no hino ku isi.
Itsinda Mpuzamahanga ry’Ubucukuzi bw’Amabuye y’Agaciro (International Mining Team Publishing Ltd) 2 Claridge Court, Lower Kings Road Berkhamsted, Hertfordshire Ubwongereza HP4 2AF, Ubwongereza