I-Hydrogen Sulfide Corrosion in Oil and Gas Industries

Amapayipi adlala indima ebalulekile emkhakheni kawoyela negesi ngokwenza kube lula ukuthuthwa kwemikhiqizo iye ezikhungweni zokwelapha, ezindaweni zokugcina izinto, nasezindaweni zokuhluzwa. Njengoba lawa mapayipi athutha izinto ezibalulekile neziyingozi, noma yikuphi ukwehluleka okungaba khona kunemiphumela ephawulekayo yezezimali neyemvelo, okuhlanganisa ingozi yokulahlekelwa kwezomnotho okuyinhlekelele nezinsongo ekuphileni komuntu. Ukwehluleka kungase kuvele ezintweni ezihlukahlukene, okuhlanganisa ukugqwala (ukuqhekeka kwangaphandle, kwangaphakathi, nokucindezeleka), izinkinga zemishini (njengamaphutha wezinto ezibonakalayo, umklamo, nokwakhiwa), imisebenzi yezinkampani zangaphandle (ngengozi noma ngamabomu), izinkinga zokusebenza (ukungasebenzi kahle, ukungasebenzi kahle, ukungasebenzi kahle, ukungasebenzi kahle, ukungasebenzi kahle, ukungasebenzi kahle, ukungasebenzi kahle), ukuphazamiseka kwezinhlelo zokuvikela, noma amaphutha omqhubi), kanye nezenzakalo zemvelo (njengokushaya umbani, izikhukhula, noma ukushintshwa komhlaba).

Ukusatshalaliswa kokwehluleka eminyakeni eyi-15 (1990–2005) kuyaboniswa. Ukugqwala kuyisici esiyinhloko esinomthelela, okubalelwa ku-46.6% ukwehluleka kwamapayipi egesi yemvelo kanye no-70.7% wamapayipi kawoyela ongahluziwe. Ukuhlolwa kwezindleko zokugqwala okwenziwa yinkampani kawoyela negesi ehlonishwayo kwembula ukuthi ngonyaka wezimali ka-2003, izindleko zokugqwala zaba cishe izigidi ezingama-USD 900. Izindleko zomhlaba wonke ezidalwe ukugqwala emkhakheni kawoyela negesi zilinganiselwa ku-USD 60 billion. E-United States kuphela, izindleko ezibhaliwe ezihlobene nokugqwala ezimbonini ezinjalo zifinyelela ku-USD 1.372 billion. Ngaphezu kwalokho, uma kucatshangelwa ukwanda kwesidingo samandla atholakala kuwoyela negesi kanye nokukhathazeka okuhlobene, izindleko zokugqwala emhlabeni wonke embonini kulindeleke ukuthi ziqhubeke nokukhuphuka. Ngakho-ke, kunesidingo esibalulekile sokuhlolwa kwengozi okusebenzayo okulinganisa ukusebenza kahle kwezindleko nokuphepha.

Ukuqinisekisa ubuqotho bamapayipi kubalulekile ekusebenzeni okuphephile, ukulondolozwa kwemvelo, kanye nokusebenza kwezimpahla ezinkulu zokukhiqiza. Ukugqwala kubangela usongo olukhulu, ngaphandle nangaphakathi. Ukugqwala kwangaphandle kungabangelwa izici ezifana ne-oxygen ne-chloride endaweni yangaphandle [6]. Ngokuphambene, ukugqwala kwangaphakathi kungase kusuke ezintweni ezifana ne-hydrogen sulfide (H2S), i-carbon dioxide (CO2), nama-asidi aphilayo akhona oketshezini lokukhiqiza. Ukugqwala okunganakiwe nokungalawuleki kwamapayipi kungaholela ekuvuzeni nasekuhlulekeni okuyinhlekelele. Ukugqwala kwangaphakathi kube yinto ekhathaza kakhulu, ehlanganisa cishe u-57.4% no-24.8% wokungagqwali kwamapayipi kawoyela ongahluziwe nawegesi yemvelo, ngokulandelana . Ukubhekana nokugqwala kwangaphakathi kubalulekile ukuze kugcinwe ubuqotho nokuphepha kwemboni.

Emkhakheni kawoyela negesi, ukugqwala kuvame ukuhlukaniswa ngezinhlobo ezimbili eziyinhloko: ukugqwala okumnandi nokumuncu, okuvame kakhulu ezindaweni ezinezingcindezi eziphakeme ze-H2S ne-CO2 (PH2S ne-PCO2). Lezi zinhlobo zokugqwala zimele izinselelo ezibalulekile embonini. Ukugqwala kuphinde kuhlukaniswe ngezigaba ezintathu ezisekelwe kwisilinganiso se-PCO2 kuya ku-PH2S: ukugqwala okumnandi (PCO2/PH2S > 500), ukugqwala okumuncu (PCO2/PH2S okusuka ku-20 kuye ku-500), nokugqwala okumuncu (PCO2/PH2S

Izici ezibalulekile ezithonya ukugqwala zihlanganisa amazinga e-PH2S kanye ne-PCO2, kanye nezinga lokushisa namanani e-pH. Lokhu okuguquguqukayo kuthinta kakhulu ukuqedwa kwamagesi abolayo, ngaleyo ndlela kube nomthelela wezinga nendlela yokwakheka komkhiqizo wokugqwala ezindaweni ezinoshukela nezimuncu. Amazinga okushisa asheshisa ukusebenza kwamakhemikhali futhi andise ukunyibilika kwegesi, kube nomthelela emazingeni okugqwala. Amazinga e-pH anquma i-asidi yendawo noma i-alkalinity, ene-pH ephansi esheshisa ukugqwala kanye ne-pH ephezulu engase ibangele izindlela zokugqwala zasendaweni. Amagesi e-CO2 ne-H2S ancibilikisiwe akhiqiza ama-asidi abolayo emanzini, asabela ngezindawo zensimbi ukuze akhe izinhlanganisela ezivikela kancane, ngaleyo ndlela kusheshiswe ukugqwala. Ukugqwala okumnandi ngokuvamile kuhilela ukwakhiwa kwe-metal carbonates (MeCO3), kuyilapho ukugqwala okumuncu kuhilela ukwakheka okuhlukahlukene kwe-metal sulfide.

Emkhakheni kawoyela negesi, ukwehluleka kwempahla okubangelwa ukugqwala kuzo zombili izindawo ezimuncu nezimnandi kubangela izinselele ezihlukahlukene zokuphepha, ezomnotho, nezemvelo. Umfanekiso wesi-2 ubonisa umnikelo ohlobene wezinhlobo ezahlukene zokwehluleka ukugqwala phakathi nawo-1970. Ukugqwala okumuncu okudalwe i-H2S kukhonjwa njengembangela eyinhloko yokungasebenzi kahle okuhlobene nokugqwala kule mboni, nokusabalala kwayo kukhula kancane kancane ngokuhamba kwesikhathi. Ukubhekana nokugqwala okumuncu kanye nokusungula izinyathelo zokuvimbela kubalulekile ekulawuleni ubungozi obuhlobene nezimboni ze-petroleum.

Ukuphatha nokucubungula izinto eziqukethe i-H2S kubangela izinselelo ezinkulu emkhakheni kawoyela negesi. Ukuqonda ubunkimbinkimbi bokugqwala kwe-H2S kubalulekile, njengoba kubeka engcupheni enkulu kumathuluzi nengqalasizinda, kukhuphula ubungozi bokwehluleka kwesakhiwo kanye nezingozi ezingaba khona. Lolu hlobo lokugqwala ngokusobala lunciphisa isikhathi sokuphila kwemishini, kudinge ukulungiswa okumba eqolo noma imizamo yokuyishintsha. Ngaphezu kwalokho, kuthikameza ukusebenza kahle, okuholela ekwehleni komkhiqizo kanye namazinga aphezulu okusetshenziswa kwamandla.

Ukuqonda nokubhekana nezinselele ezibangelwa ukugqwala kwe-H2S phakathi kwezimboni ezinjalo kuveza izinzuzo eziphawulekayo. Izinyathelo zokuphepha ziqiniswa ngokuvimbela ukuwohloka nokugcinwa kwemishini, futhi amathuba ezingozi nemiphumela yemvelo ayancishiswa. Leli su liphinde landise isikhathi sokuphila kwezinto zokusebenza, linciphise isidingo sokushintshwa ezibizayo futhi linciphise isikhathi sokuphumula esidingekayo ukuze kulungiswe. Ukwengeza, ithuthukisa ukusebenza kahle ngokuqinisekisa izinqubo ezisebenzayo nezingashintshi, ukunciphisa ukusetshenziswa kwamandla, nokuqinisa ukwethembeka kokugeleza.

Ukuhlola izindawo zophenyo olwengeziwe, okuhlanganisa nobuchwepheshe bokunamathela obuphambili, izinto ezintsha, izinqubo ze-electrochemical, nobuchwepheshe obusafufusa, kubalulekile. Ukuthuthukiswa kwezindlela ezintsha, njengezinhlelo zokuqapha eziqhubekayo kanye nokubikezela imodeli, kubonisa amandla okuthuthukisa izinyathelo zokuphepha. Ukusebenzisa ubuhlakani bokwenziwa obuthuthukisiwe kanye nezibalo ezithuthukile ekuphatheni, ekuqaguleni, nasekulawuleni ukugqwala kuyinkambu esafufusayo edinga ukuhlolwa okwengeziwe.

Umnyango we-R&D we-Vigor uthuthukise ngempumelelo ipulagi yebhuloho eliyinhlanganisela entsha (fiberglass) elimelana ne-hydrogen sulfide. Ibonise ukusebenza okuhle kakhulu kukho kokubili ukuhlolwa kwelebhu kanye nokuhlolwa kwensimu yamakhasimende. Ithimba lethu lezobuchwepheshe likuhlomele ngokugcwele ukwenza ngendlela oyifisayo futhi likhiqize lawa mapulagi ngokwezidingo ezithile zesayithi. Ukuze uthole imibuzo mayelana nezixazululo zepulagi yebhuloho le-Vigor, xhumana nethimba lethu ukuze uthole imikhiqizo eklanyelwe kanye nekhwalithi yesevisi ehlukile.

Ukuze uthole ulwazi olwengeziwe, ungabhalela ibhokisi lethu lemeyiliinfo@vigorpetroleum.com&marketing@vigordrilling.com