化工进展
化工進展
화공진전
Chemical Industry and Engineering Progress
2015年
12期
4191-4197
,共7页
系统工程%(用)%优化设计%夹点技术%乙烯%复叠制冷
繫統工程%(用)%優化設計%夾點技術%乙烯%複疊製冷
계통공정%(용)%우화설계%협점기술%을희%복첩제랭
systems engineering%exergy%optimal design%pinch%ethylene%cascade refrigerating system
乙烯装置的分离过程要在低温下进行,由乙烯制冷系统提供所需冷量.乙烯制冷系统为封闭式循环,独立于分离单元之外.将乙烯分离单元与制冷系统同时优化,能有效提高装置用能效率.复叠式制冷级数是当前乙烯工业中使用最为广泛的制冷技术.本文针对乙烯分离过程和配套的复叠制冷系统,采用Aspen Hysys进行模拟并进行?分析,发现系统主要的?损失发生在换热与压缩两部分,其占总?损失的 83%,为节能的重点.进而通过夹点技术对冷剂配置进行分析,发现?56℃以上各温位的冷量配置不合理,远超过理论最小值,?56℃以下各温位的冷量基本达到理论最小值.提出了采用多股流换热器的换热网络理论设计方法,并对冷剂进行重新配置,该理论方案可以降低丙烯制冷压缩机约 30%的功耗,并节约部分乙烯制冷压缩机功耗,显著降低了乙烯深冷分离能耗.
乙烯裝置的分離過程要在低溫下進行,由乙烯製冷繫統提供所需冷量.乙烯製冷繫統為封閉式循環,獨立于分離單元之外.將乙烯分離單元與製冷繫統同時優化,能有效提高裝置用能效率.複疊式製冷級數是噹前乙烯工業中使用最為廣汎的製冷技術.本文針對乙烯分離過程和配套的複疊製冷繫統,採用Aspen Hysys進行模擬併進行?分析,髮現繫統主要的?損失髮生在換熱與壓縮兩部分,其佔總?損失的 83%,為節能的重點.進而通過夾點技術對冷劑配置進行分析,髮現?56℃以上各溫位的冷量配置不閤理,遠超過理論最小值,?56℃以下各溫位的冷量基本達到理論最小值.提齣瞭採用多股流換熱器的換熱網絡理論設計方法,併對冷劑進行重新配置,該理論方案可以降低丙烯製冷壓縮機約 30%的功耗,併節約部分乙烯製冷壓縮機功耗,顯著降低瞭乙烯深冷分離能耗.
을희장치적분리과정요재저온하진행,유을희제랭계통제공소수랭량.을희제랭계통위봉폐식순배,독립우분리단원지외.장을희분리단원여제랭계통동시우화,능유효제고장치용능효솔.복첩식제랭급수시당전을희공업중사용최위엄범적제랭기술.본문침대을희분리과정화배투적복첩제랭계통,채용Aspen Hysys진행모의병진행?분석,발현계통주요적?손실발생재환열여압축량부분,기점총?손실적 83%,위절능적중점.진이통과협점기술대랭제배치진행분석,발현?56℃이상각온위적랭량배치불합리,원초과이론최소치,?56℃이하각온위적랭량기본체도이론최소치.제출료채용다고류환열기적환열망락이론설계방법,병대랭제진행중신배치,해이론방안가이강저병희제냉압축궤약 30%적공모,병절약부분을희제냉압축궤공모,현저강저료을희심랭분리능모.
The separation process of an ethylene plant should be operated at low temperature,and a refrigeration system supplies the cooling demand. The refrigeration system in an ethylene plant is a closed cycle system independent of the separation process. The energy efficiency can be effectively improved if the separation process and refrigeration system are optimized simultaneously. Cascade refrigerating systems are most widely used in ethylene plants. In this paper,Aspen Hysys is used to simulate and analyze an ethylene separation process with a cascade refrigerating system. The exergy analysis showed lower efficiency of heat exchanger and compressor sections,whose exergy loss contribute 83% of the whole loss of the system. So energy conservation work should focus on the two sections. Then pinch technology is used to analyze refrigerant configuration. It is found that refrigerant usage above?56℃ is far more than the theoretical minimum quantity,and refrigerant usage below?56℃ is reasonable. A novel design method by using multi-pass exchangers for heat exchanger networks is proposed and the refrigerant usage is reconfigured. The new design can reduce about 30% propylene compressor work and some ethylene compressor work consumption,reducing the energy consumption of the ethylene separation significantly.
