本文關(guān)鍵詞：煤制甲醇過(guò)程的低溫余熱利用與碳減排工藝研究　出處：《華南理工大學(xué)》2016年博士論文　論文類(lèi)型：學(xué)位論文

  更多相關(guān)文章： 煤制甲醇 低溫余熱 夾點(diǎn)分析 碳捕集技術(shù) 節(jié)能減排

【摘要】：中國(guó)是世界最大的甲醇生產(chǎn)和消費(fèi)國(guó)。基于富煤貧油少氣的能源現(xiàn)狀,國(guó)內(nèi)甲醇生產(chǎn)是以煤氣化制甲醇為主。煤制甲醇工藝能耗高,并且碳排放強(qiáng)度大。在煤制甲醇生產(chǎn)過(guò)程中,釋放大量低品位余熱,很多企業(yè)未加有效利用。另外,在CO_2回收和捕集情景下,CO_2壓縮機(jī)組消耗大量電能,最終轉(zhuǎn)化為低溫?zé)崃颗欧�。將這些余熱加以利用,可在推進(jìn)減排二氧化碳的同時(shí)實(shí)現(xiàn)節(jié)能降耗。本文以煤制甲醇過(guò)程的低溫余熱及碳減排為研究?jī)?nèi)容,通過(guò)熱集成、余熱發(fā)電和過(guò)程耦合技術(shù),在流程模擬的基礎(chǔ)上,對(duì)提出的煤制甲醇過(guò)程的低溫余熱利用工藝和碳減排集成工藝進(jìn)行了評(píng)價(jià)分析。以GE水煤漿氣化為基礎(chǔ)的煤制甲醇工藝包括:水煤漿氣化、激冷除塵、水煤氣變換、低溫甲醇洗、甲醇合成、甲醇精餾等單元。過(guò)程模擬軟件AspenPlus為工具,建立了60萬(wàn)噸產(chǎn)能的煤制甲醇流程模擬。通過(guò)模擬計(jì)算,研究了各個(gè)單元內(nèi)的流程配置、工藝參數(shù),為煤制甲醇過(guò)程的低溫余熱利用和碳減排工藝的研究提供了工藝數(shù)據(jù)基礎(chǔ)。煤制甲醇過(guò)程是大量反應(yīng)熱及高溫物流熱量釋放的工藝過(guò)程。夾點(diǎn)分析表明,氣化及灰水處理、水煤氣變換、甲醇合成及精餾單元的換熱網(wǎng)絡(luò)都是只需冷公用工程的閾值問(wèn)題,并且存在著大量的低溫余熱。甲醇合成及精餾單元的余熱量較大,但溫度低于70℃,難以利用。氣化及灰水處理,水煤氣變換的溫度在80~150℃低溫余熱,可以作為煤制甲醇工藝過(guò)程的低品位熱能,進(jìn)一步進(jìn)行余熱發(fā)電利用。有機(jī)朗肯循環(huán)發(fā)電是應(yīng)用低沸點(diǎn)有機(jī)物做循環(huán)工質(zhì),將低品位熱能轉(zhuǎn)換為電能的余熱利用技術(shù)。應(yīng)用R600a為煤制甲醇過(guò)程余熱發(fā)電的有機(jī)工質(zhì),對(duì)余熱發(fā)電單元進(jìn)行了夾點(diǎn)分析和換熱網(wǎng)絡(luò)的設(shè)計(jì)。在最大余熱回收量時(shí),有機(jī)朗肯發(fā)電單元是一個(gè)只需冷公用工程的換熱單元,總體單元內(nèi)熱源物流產(chǎn)生總熱量64.2MW,冷、熱物流單元內(nèi)換熱量32.2MW。對(duì)60萬(wàn)噸產(chǎn)能的甲醇廠,余熱利用的發(fā)電功率為3.95MW,凈輸出電為3.55MW,投資回收期為3年。為降低煤制甲醇工藝外排CO_2,提高CO_2捕集效率,將低溫甲醇洗酸氣脫除單元的解吸與CO_2壓縮進(jìn)行過(guò)程耦合。通過(guò)提高CO_2解吸的甲醇富液分離溫度、降壓閃蒸,可大幅提高CO_2捕集率。將低溫甲醇洗流程中甲醇富液升溫所提供的低溫冷量用于壓縮過(guò)程的低溫冷卻,在提升CO_2捕集率的情況下,同時(shí)可節(jié)省壓縮過(guò)程電力消耗9.6%,降低冷卻水消耗36.1%。從提高單位能量利用效率、提高CO_2捕集率兩方面考慮,80~90%為集成碳捕集流程的合理CO_2捕集范圍。在碳捕集技術(shù)應(yīng)用于煤制甲醇過(guò)程時(shí),CO_2多級(jí)壓縮也會(huì)產(chǎn)生低溫余熱。帶常規(guī)碳捕集的煤制甲醇進(jìn)行有機(jī)朗肯余熱發(fā)電,對(duì)外供電約4.32MW,相應(yīng)每噸甲醇的成本降低39元。在應(yīng)用低溫甲醇洗與CO_2壓縮集成工藝時(shí),CO_2捕集率提高到85%;CO_2壓縮過(guò)程采用四級(jí)壓縮,余熱量與常規(guī)碳捕集過(guò)程相比略有下降,余熱電站對(duì)外供電約4MW。余熱的發(fā)電利用減少了電力的使用,間接減少了煤制甲醇過(guò)程的碳排放。
[Abstract]:Chinese is the world's largest methanol production and consumption in the energy situation. Based on the rich coal less gas, the domestic methanol production is dominated by coal gasification methanol. Coal methanol process of high energy consumption, and carbon emission intensity. In the production process of coal methanol, the release of a large number of low grade waste heat, a lot of enterprises is not effective use. In addition, the CO_2 recovery and capture scenarios, CO_2 compressors consume a lot of power, eventually transformed into low temperature heat emission. The heat will be used to achieve energy saving in advance of carbon dioxide emissions at the same time. In this paper, the low temperature waste heat and carbon emission reduction process of coal methanol as the research content, through the heat integrated waste heat power generation and process coupling technology, based on the flow simulation, the low temperature waste heat utilization technology and integrated technology for carbon emission reduction of coal methanol process proposed were evaluated with GE analysis. For coal water slurry gasification Including coal to methanol technology based on the coal water slurry gasification, chilled dust, water gas shift, Rectisol, methanol synthesis, methanol distillation unit. Process simulation software AspenPlus, the establishment of the production capacity of 600 thousand tons of coal methanol process simulation. Through simulation research, each unit within the process configuration and the process parameters, process data provides a foundation for the study of the utilization of low temperature waste heat of coal methanol process and carbon emission reduction process. Coal methanol process is the process a large number of high temperature reaction heat and heat release. The logistics pinch analysis shows that the gasification and ash water treatment, water gas shift, heat exchanger network synthesis and methanol distillation the unit is only threshold of cold utilities, and there are a lot of low-temperature waste heat. The heat quantity of methanol synthesis and distillation unit is large, but the temperature is below 70 DEG C, it is difficult to use gas and ash water treatment, Water gas shift temperature at 80~150 degrees of low temperature waste heat, can be used as low-grade heat coal methanol process, further the use of waste heat power generation. The organic Rankine cycle power generation is using low boiling point organic as refrigerant, the low grade heat energy to heat energy utilization technology. The application of R600a for organic fluid process coal methanol waste heat power generation, cogeneration unit of heat exchanger network pinch analysis and design. The maximum heat recovery amount, organic Rankine power generating unit is a heat exchanger unit only cold utilities, the overall unit heat source logistics total heat 64.2MW, cold heat, logistics unit heat 32.2MW. production capacity of 600 thousand tons of methanol plant, power generation of waste heat utilization for 3.95MW, the net output power is 3.55MW, the payback period is 3 years. In order to reduce the coal methanol efflux of CO_2, improve the CO_2 capture efficiency will be. Desorption and CO_2 low temperature methanol washing acid gas removal unit compression process coupling by increasing the separation temperature, methanol rich liquid CO_2 desorption pressure flash, can greatly improve the capture rate of CO_2. The low temperature methanol washing process of methanol in liquid rich heating cold quantity are provided for the compressed cryogenic cooling process, in ascension CO_2 capture rate, and can save the compression process 9.6% of the electricity consumption, reduce the consumption of cooling water from 36.1%. improve energy efficiency, improve the capture rate of CO_2 in two aspects, the reasonable CO_2 80~90% integrated carboncapture flow capture range. The carbon capture technology in coal methanol process CO_2, multistage compression will produce low temperature waste heat. Coal methanol with conventional carbon capture for organic Rankine heat generation, the power is about 4.32MW, the corresponding cost reduced by 39 yuan per ton of methanol. Washing and CO_2 pressure in the application of low temperature methanol The integrated process of shrinkage, CO_2 capture rate increased to 85%; the CO_2 compression process using four stage compression, residual heat and conventional carbon capture process phase decreased slightly, the external power supply of about 4MW. waste heat power plant waste heat generation by decreasing the use of electricity, indirect coal to methanol process to reduce carbon emissions.

【學(xué)位授予單位】：華南理工大學(xué)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2016
【分類(lèi)號(hào)】：TQ223.121

【參考文獻(xiàn)】

相關(guān)期刊論文 前2條

1 張學(xué)模,儲(chǔ)政,古俊智;脫CO_2技術(shù)進(jìn)展及評(píng)價(jià)[J];化學(xué)工業(yè)與工程技術(shù);2001年02期

2 朱世勇;合成氣脫二氧化碳的技術(shù)經(jīng)濟(jì)評(píng)價(jià)[J];化學(xué)工業(yè)與工程技術(shù);1995年01期

相關(guān)博士學(xué)位論文 前1條

1 張彥;煤氣化甲醇聯(lián)產(chǎn)電系統(tǒng)的工業(yè)示范研究[D];中國(guó)科學(xué)院研究生院（工程熱物理研究所）;2009年

相關(guān)碩士學(xué)位論文 前1條

1 金鑫;煤基甲醇和電力聯(lián)產(chǎn)過(guò)程的物流和能量集成設(shè)計(jì)[D];華南理工大學(xué);2013年

，

本文編號(hào)：1411348