Tsarin konewa na Oxy

Oxy-fuel combustion shine tsari na ƙone man fetur ta amfani da iskar oxygen mai tsabta, ko cakuda iskar oxygen da iskar gas, maimakon iska. Tunda bangaren nitrogen na iska ba a dumama shi ba, ana rage amfani da man fetur, kuma yanayin zafi na wuta yana yiwuwa. A tarihi, amfani na farko na konewar oxy-fuel ya kasance a cikin walda da yankan karafa, musamman ƙarfe, tunda oxy-fues yana ba da damar yanayin zafi na wuta fiye da yadda za'a iya samu tare da harshen wuta na iska. Har ila yau, ya sami kulawa mai yawa a cikin 'yan shekarun nan a matsayin yiwuwar kama carbon da fasahar adanawa.

A halin yanzu ana yin bincike a cikin kashe masana'antun samar da man fetur tare da haɗin iskar oxygen maimakon iska. Kusan dukkanin nitrogen an cire su daga iska mai shigowa, suna samar da rafi wanda ke da kusan 95% oxygen.[./Oxy-fuel_combustion_process#cite_note-3 [1]] Yin wuta tare da iskar oxygen mai tsabta zai haifar da yawan zafin wuta, don haka ana narkar da cakuda ta hanyar haɗuwa da iskar gas mai sake amfani da shi, ko ƙonewa. Hakanan za'a iya amfani da iskar gas ɗin da aka sake amfani da ita don ɗaukar man fetur a cikin bututun ruwa da kuma tabbatar da isasshen canja wurin zafi zuwa duk wuraren bututun ruwa. Oxy-fuel konewa yana samar da kusan kashi 75% ƙasa da iskar gas fiye da iska mai konewa kuma yana samar da hayaki wanda ya kunshi CO2 da H2O (duba adadi).

 Tattalin arziki da inganci 
Dalilin yin amfani da man fetur na oxy shine samar da iskar gas mai cike da CO2 a shirye don tsare. Oxy-fuel konewa yana da fa'idodi masu mahimmanci akan tsire-tsire masu amfani da iska na gargajiya. Daga cikin wadannan sune:

 An rage yawan da kuma girman iskar gas da kusan kashi 75%.
 Saboda an rage yawan iskar gas, an rasa karancin zafi a cikin iskar gas.
 Za'a iya rage girman kayan aikin maganin iskar gas da kashi 75%.
 Gas din shine CO2, wanda ya dace da tsare-tsare.
 Adadin gurɓataccen abu a cikin iskar gas ya fi girma, yana sauƙaƙa rabuwa.
 Yawancin iskar gas ɗin suna iya haɗuwa; wannan yana sa rabuwa ta matsawa ta yiwu.
 Za'a iya kama zafi kuma a sake amfani da shi maimakon ya ɓace a cikin iskar gas.
 Saboda nitrogen daga iska ba ya nan, samar da nitrogen oxide ya ragu sosai.
 Idan man fetur ya ƙunshi sulfur, ana iya dawo da sulfuric acid maimakon a saki shi a matsayin mai gurɓata muhalli mai haɗari ko "ya ɓace" a cikin gas din.

A fannin tattalin arziki wannan hanyar tana da tsada fiye da kayan aikin iska na gargajiya. Babban matsalar ita ce raba iskar oxygen daga iska. Wannan tsari yana buƙatar makamashi mai yawa, kusan 15% na samarwa ta tashar wutar lantarki mai amfani da kwal za a iya cinye shi don wannan tsari. Koyaya, ana iya amfani da sabuwar fasahar da ba ta da amfani da ake kira ƙonewar sinadarai  don rage wannan farashi. A cikin ƙonewar sinadarai, iskar oxygen da ake buƙata don ƙone kwal ana samar da ita a ciki ta hanyar halayen oxidation da ragewa, sabanin amfani da hanyoyin da suka fi tsada na samar da iskar oxygen ta hanyar raba shi daga iska.

A halin yanzu ba tare da wani buƙatar rage hayaki na CO2 ba, oxy-fuel ba gasa ba ne. Koyaya, oxy-fuel wani zaɓi ne mai yiwuwa don cire CO2 daga iskar gas daga masana'antar man fetur mai amfani da iska. Koyaya, mai mai mai Mai mayar da hankali ga iskar oxygen na iya taimakawa, saboda kawai yana cire nitrogen.

A cikin masana'antu ban da samar da wutar lantarki, konewar oxy-fuel na iya zama gasa saboda wadatar zafi mai mahimmanci. Oxy-fuel konewa ya zama ruwan dare a fannoni daban-daban na samar da ƙarfe.

Masana'antar gilashi tana canzawa zuwa man fetur tun farkon shekarun 1990 saboda murfin gilashi yana buƙatar zafin jiki na kusan digiri 1500 C, wanda ba a iya samun tattalin arziki a 2" href="./Adiabatic_flame_temperature" id="mwRQ" rel="mw:WikiLink" title="Adiabatic flame temperature">yanayin zafi na wuta na adiabatic don konewar iska-mai sai dai idan an sake farfado da zafi tsakanin rafin hayaki da rafin iska mai shigowa. An haɓaka su a tsakiyar karni na 19, masu sabunta wutar lantarki na gilashi sune manyan bututun tubali masu tsada cike da tubali da aka shirya a cikin tsari na allon don kama zafi yayin da iskar gas ta fita daga cikin wutar lantarki. Lokacin da aka yi amfani da bututun ruwa sosai, ana juyar da iskar iska kuma bututun ruwa ya zama iska, yana fitar da zafi a cikin iska mai shigowa, kuma yana ba da damar yanayin zafi mafi girma fiye da yadda za'a iya samu tare da iska-fuel kawai. Saiti biyu na hanyoyin sabuntawa sun ba da izinin juyawa da iska a lokuta na yau da kullun, don haka kula da zafin jiki mai girma a cikin iska mai shigowa. Ta hanyar ba da izinin gina sabbin murhu ba tare da kuɗin masu sabuntawa ba, kuma musamman tare da ƙarin fa'idar rage nitrogen oxide, wanda ke ba da damar tsire-tsire na gilashi su sadu da ƙuntatawa na fitarwa, oxy-fuel yana da tsada ba tare da buƙatar rage fitar da CO2 ba. Hakanan konewar Oxy-fuel yana rage sakin CO2 a wurin masana'antar gilashi, kodayake ana iya kawar da wannan ta hanyar samar da CO2 saboda samar da wutar lantarki wanda ya zama dole don samar da iskar oxygen don tsarin konewa.

Oxy-fuel konewa na iya zama mai tsada a cikin ƙone ƙarancin ƙarancin BTU mai haɗari. Sau da yawa ana haɗa shi da ƙonewa don rage nitrogen oxide, tunda iskar oxygen mai tsabta na iya daidaita halaye na ƙonewa na harshen wuta.

 Shuke-shuke masu tuka jirgin sama 

Akwai tsire-tsire masu matukin jirgi da ke fuskantar gwajin tabbacin ra'ayi na farko don kimanta fasahar don haɓaka har zuwa tsire-shuke na kasuwanci, gami da

 Callide Tashar Wuta a Queensland, Ostiraliya 
 Tashar wutar lantarki ta Schwarze Pumpe a Spremberg, Jamus
 CIUDEN in Cubillos del Sil, Spain 
 Wurin Nuna Wutar NET a La Porte, Texas, Amurka 

 Shuka na White Rose 
Ɗaya daga cikin binciken shari'a na konewar oxy-fuel shine yunkurin White Rose a Arewacin Yorkshire, Ingila. Shirin da aka tsara shi ne tashar wutar lantarki ta oxy-fuel tare da rabuwa da iska don kama tan miliyan biyu na carbon dioxide a kowace shekara. Za a kawo carbon dioxide ta hanyar bututun mai don a rufe shi a cikin ruwan gishiri a ƙarƙashin Tekun Arewa. Koyaya, a ƙarshen 2015 da farkon 2016, biyo bayan janyewar kudade daga Drax Group da gwamnatin Burtaniya, an dakatar da aikin. Rashin kudade da ba a tsammani ba daga Shirin Kasuwancin CCS na gwamnatin Burtaniya, tare da raguwar tallafi don makamashi mai sabuntawa, ya bar White Rose Plant ba tare da isasshen kudade don ci gaba da ci gaba.

 Tasirin muhalli 
Ɗaya daga cikin manyan tasirin muhalli na ƙonewa burbushin mai shine sakin CO 2, wanda ke taimakawa wajen sauyin yanayi . Saboda konewar oxyfuel yana haifar da iskar gas wanda ya riga ya sami babban taro na CO , yana sa ya fi sauƙi don tsaftacewa da adana CO 2 maimakon sakewa zuwa yanayi. 

Yawancin albarkatun mai, irin su gawayi da shale mai, suna haifar da toka sakamakon konewa. Wannan toka kuma yana buƙatar zubar da shi, wanda zai iya tasiri ga muhalli. Ya zuwa yanzu bincike ya nuna cewa, gabaɗaya, konewar oxyfuel ba ta da tasiri sosai kan abun da ke tattare da toka. Ma'aunai sun nuna irin ma'adinan ma'adinai da ƙarfe mai nauyi ba tare da la'akari da ko an yi amfani da yanayin iska ko iskar oxygen ba.   Duk da haka, ɗayan sanannen bangaranci shine tokar oxyfuel sau da yawa yana da ƙananan ƙwayoyin calcium oxide ko calcium hydroxide (lemun tsami kyauta). Lemun tsami kyauta yana samuwa lokacin da ma'adinan carbonate a cikin man fetur kamar kwal da shale mai suna bazuwa a yanayin zafi da ke faruwa a lokacin konewa ( calcination ). Calcination shine amsa ma'auni kuma mafi girman matsi na CO  yana canza ma'auni don goyon bayan CaCO3 da MgCO3 bi da bi. Lemun tsami kyauta yana amsawa kuma yana iya yuwuwar tasiri ga muhalli, misali ta ƙara alkalinity na ash. Saboda konewar oxyfuel yana faruwa a cikin yanayi mai wadatar CO 2, raguwa yana raguwa kuma ash gabaɗaya yana ƙunshe da ƙarancin lemun tsami.   Ana amfani da desulfurization na iskar gas yawanci don ƙara pH na iskar hayaki ko samfurin su lokacin da ake amsawa da danshi na yanayi ( ruwan acid ). Bayan sulfur da oxides, wani abu mai yuwuwar ruwan acid yana samuwa daga nitric da nitrous oxide suna hulɗa da ruwa - kawar da nitrogen daga konewa yana rage wannan abu gaba ɗaya.

 Manazarta 

Rukuni:Shafuka masu fassarorin da ba'a duba ba