The traditional methods for synthesizing flexible heat exchanger networks(HENs)are not directly applicable to inter-plant HEN challenges,primarily due to the spread of system uncertainty across plants via intermedium ...The traditional methods for synthesizing flexible heat exchanger networks(HENs)are not directly applicable to inter-plant HEN challenges,primarily due to the spread of system uncertainty across plants via intermedium fluid circles.This complicates the synthesis process significantly.To tackle this issue,this study proposes a decomposed stepwise methodology to facilitate the flexible synthesis of the interplant HENs performing indirect heat integration.A decomposition strategy is proposed to divide the overall network into manageable sub-networks by dissecting the intermedium fluid circles.To address the variability in intermedium fluid temperatures,a temperature fluctuation analysis approach is developed and a heuristic rule is introduced to maintain the temperature feasibility of the intermedium fluids.To ensure adequate flexibility and cost-effectiveness of the designed networks,flexibility analysis and network retrofit steps are conducted through model-based optimization techniques.The efficacy of the method is demonstrated through two case studies,showing its potential in achieving the desired operational flexibility for inter-plant HENs.展开更多
China is rich of oil shale as one of alternative fossil energy resources.The exploitation and utilization of oil shale are strategically important in alleviating the shortage of oil and gas resources in China.However,...China is rich of oil shale as one of alternative fossil energy resources.The exploitation and utilization of oil shale are strategically important in alleviating the shortage of oil and gas resources in China.However,low utilization rate of raw material,low oil yield,and high content of heavy components in the oil are the main problems in current Fushun type oil shale refinery technology.An indirectly heated moving bed is developed to de-bottleneck Fushun type technology.The oil shale refinery process with the indirectly heated moving bed is modeled and simulated in this work.Based on the simulation,a techno-economic analysis is performed and compared with the conventional Fushun oil shale refinery process.Results show that:for a shale refinery of 3.0 Mt/y scale,375 t/h oil shale retorting requires 149.6 MW of heat,in which 60%of the heat is produced by combustion of the oil shale pyrolysis gas,while remaining 40%from the coal gasified gas.In consideration of investment and operation,the cost of product shale oil of the new process is 2636 CNY/t,which is 12%lower than that of the conventional Fushun refinery process.This benefit comes from higher utilization of raw material and oil yield of the new process.The competitive crude oil price of the indirectly heated moving bed refinery process is about 51$/bbl,while that of the Fushun refinery process is 58$/bbl.During 2017 year,the crude oil price fluctuates at around 50$/bbl,thus the new indirectly heated moving bed refinery process shows better economic competitiveness.展开更多
基金financial support provided by the National Natural Science Foundation of China(22378045,22178045).
文摘The traditional methods for synthesizing flexible heat exchanger networks(HENs)are not directly applicable to inter-plant HEN challenges,primarily due to the spread of system uncertainty across plants via intermedium fluid circles.This complicates the synthesis process significantly.To tackle this issue,this study proposes a decomposed stepwise methodology to facilitate the flexible synthesis of the interplant HENs performing indirect heat integration.A decomposition strategy is proposed to divide the overall network into manageable sub-networks by dissecting the intermedium fluid circles.To address the variability in intermedium fluid temperatures,a temperature fluctuation analysis approach is developed and a heuristic rule is introduced to maintain the temperature feasibility of the intermedium fluids.To ensure adequate flexibility and cost-effectiveness of the designed networks,flexibility analysis and network retrofit steps are conducted through model-based optimization techniques.The efficacy of the method is demonstrated through two case studies,showing its potential in achieving the desired operational flexibility for inter-plant HENs.
基金the National Basic Research Program(2014CB744306)the China NSF projects(21676101 and 21736004).
文摘China is rich of oil shale as one of alternative fossil energy resources.The exploitation and utilization of oil shale are strategically important in alleviating the shortage of oil and gas resources in China.However,low utilization rate of raw material,low oil yield,and high content of heavy components in the oil are the main problems in current Fushun type oil shale refinery technology.An indirectly heated moving bed is developed to de-bottleneck Fushun type technology.The oil shale refinery process with the indirectly heated moving bed is modeled and simulated in this work.Based on the simulation,a techno-economic analysis is performed and compared with the conventional Fushun oil shale refinery process.Results show that:for a shale refinery of 3.0 Mt/y scale,375 t/h oil shale retorting requires 149.6 MW of heat,in which 60%of the heat is produced by combustion of the oil shale pyrolysis gas,while remaining 40%from the coal gasified gas.In consideration of investment and operation,the cost of product shale oil of the new process is 2636 CNY/t,which is 12%lower than that of the conventional Fushun refinery process.This benefit comes from higher utilization of raw material and oil yield of the new process.The competitive crude oil price of the indirectly heated moving bed refinery process is about 51$/bbl,while that of the Fushun refinery process is 58$/bbl.During 2017 year,the crude oil price fluctuates at around 50$/bbl,thus the new indirectly heated moving bed refinery process shows better economic competitiveness.