This paper investigates the thermal-coupled effect across the wall and the optimal heat transfer region of the wall for enhancing the energy saving effect of dividing wall column (DWC), and also studies the effects of...This paper investigates the thermal-coupled effect across the wall and the optimal heat transfer region of the wall for enhancing the energy saving effect of dividing wall column (DWC), and also studies the effects of feed thermal condition (q) and middle component composition of feed (cB) on the heat transfer process, the optimal heat transfer region, and the maximum heat transfer quantity across the wall. The simulation results show that the maximum heat transfer quantity across the wall and the potential for energy saving increase with the increase of q, while with the limitation of temperature difference across the wall, the beneficial heat transfer effect between certain range of stages, which are involved in the optimal heat transfer region, cannot be realized completely for a specific value of q. Besides, compared with q, a changing cB does not change the degree of realizing the beneficial heat transfer effect, but can bring about the variation of liquid split ratio (RL) and vapor split ratio (Rv). Thus, for achieving a maximum energy-saving effect of DWC, different q and cB need to find its own corresponding suitable heat transfer process across the wall.展开更多
This paper proposes optimization models of crude oil distillation column for both limited and unlimited feed stock and market value of known products prices. The feed to the crude distillation column was assumed to be...This paper proposes optimization models of crude oil distillation column for both limited and unlimited feed stock and market value of known products prices. The feed to the crude distillation column was assumed to be crude oil containing naphtha gas, kerosene, petrol and diesel as the light-light key, light key, heavy key and heavy-heavy key respectively. The models determined maximum concentrations of heavy key in the distillate and light key in the bottom for limited feed stock and market condition. Both were impurities in their respective positions of the column. The limiting constraints were sales specification concentration of light key in the distillate [ ], heavy key in the bottom [ ] and an operating loading constraint of flooding above the feed tray. For unlimited feed stock and market condition, the optimization models determined the optimum separation [ and ] and feed flow rate that would give maximum profit with minimum purity sales specification constraints of light key in the distillate and heavy key in the bottom as stated above. The feed loading was limited by the reboiler capacity. However, there is need to simulate the optimization models for an existing crude oil distillation column of a refinery in order to validate the models.展开更多
提出了一种基于塔总组合曲线(column grand composite curve,CGCC)确定分馏塔合理进料位置的方法——将分馏塔分别视为精馏塔与提馏塔进行物料与能量衡算,构造出与CGCC部分重合的两条相交的全塔精馏线和全塔提馏线,通过分析CGCC进料点...提出了一种基于塔总组合曲线(column grand composite curve,CGCC)确定分馏塔合理进料位置的方法——将分馏塔分别视为精馏塔与提馏塔进行物料与能量衡算,构造出与CGCC部分重合的两条相交的全塔精馏线和全塔提馏线,通过分析CGCC进料点与两曲线交点的位置关系,或定量比较两曲线上各塔板焓差大小,可以判断进料位置的合理性。研究发现,与非进料塔板相比,若CGCC进料点最靠近两曲线交点以及两曲线上进料塔板焓差取得最小值,则该进料位置最佳。两个二组分塔和一个多组分塔的应用实例表明,本文给出方法确定的分馏塔合理进料位置,与其它基于节能考虑确定分馏塔合理进料位置的方法和技术得到的计算结果基本相同。展开更多
基金supported by the Natural Science Research Youth Foundation of Hebei Higher Education of China [QN2016084]the National Natural Science Foundation of China[21878066]
文摘This paper investigates the thermal-coupled effect across the wall and the optimal heat transfer region of the wall for enhancing the energy saving effect of dividing wall column (DWC), and also studies the effects of feed thermal condition (q) and middle component composition of feed (cB) on the heat transfer process, the optimal heat transfer region, and the maximum heat transfer quantity across the wall. The simulation results show that the maximum heat transfer quantity across the wall and the potential for energy saving increase with the increase of q, while with the limitation of temperature difference across the wall, the beneficial heat transfer effect between certain range of stages, which are involved in the optimal heat transfer region, cannot be realized completely for a specific value of q. Besides, compared with q, a changing cB does not change the degree of realizing the beneficial heat transfer effect, but can bring about the variation of liquid split ratio (RL) and vapor split ratio (Rv). Thus, for achieving a maximum energy-saving effect of DWC, different q and cB need to find its own corresponding suitable heat transfer process across the wall.
文摘This paper proposes optimization models of crude oil distillation column for both limited and unlimited feed stock and market value of known products prices. The feed to the crude distillation column was assumed to be crude oil containing naphtha gas, kerosene, petrol and diesel as the light-light key, light key, heavy key and heavy-heavy key respectively. The models determined maximum concentrations of heavy key in the distillate and light key in the bottom for limited feed stock and market condition. Both were impurities in their respective positions of the column. The limiting constraints were sales specification concentration of light key in the distillate [ ], heavy key in the bottom [ ] and an operating loading constraint of flooding above the feed tray. For unlimited feed stock and market condition, the optimization models determined the optimum separation [ and ] and feed flow rate that would give maximum profit with minimum purity sales specification constraints of light key in the distillate and heavy key in the bottom as stated above. The feed loading was limited by the reboiler capacity. However, there is need to simulate the optimization models for an existing crude oil distillation column of a refinery in order to validate the models.
文摘提出了一种基于塔总组合曲线(column grand composite curve,CGCC)确定分馏塔合理进料位置的方法——将分馏塔分别视为精馏塔与提馏塔进行物料与能量衡算,构造出与CGCC部分重合的两条相交的全塔精馏线和全塔提馏线,通过分析CGCC进料点与两曲线交点的位置关系,或定量比较两曲线上各塔板焓差大小,可以判断进料位置的合理性。研究发现,与非进料塔板相比,若CGCC进料点最靠近两曲线交点以及两曲线上进料塔板焓差取得最小值,则该进料位置最佳。两个二组分塔和一个多组分塔的应用实例表明,本文给出方法确定的分馏塔合理进料位置,与其它基于节能考虑确定分馏塔合理进料位置的方法和技术得到的计算结果基本相同。
