带热压缩的低温多效蒸发海水淡化系统研究
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摘要
带热压缩的低温多效蒸发海水淡化系统由于可以利用低品位的电厂抽汽热量，可以较大的提高了造水比，有效降低了制水成本。本文对带热压缩的低温多效蒸发海水淡化系统进行了研究。
针对海水淡化系统横管降膜蒸发器，分别总结了管内冷凝侧与管外蒸发侧的换热系数关联式，比较了管内径、入口蒸汽流速、蒸汽冷凝温度、出口蒸汽干度对管内蒸汽冷凝侧换热系数的影响；研究了传热温差以及喷淋密度对管外蒸发侧换热系数的影响。结合不同的污垢系数，进行了总传热系数的影响因素分析。同时对横管降膜蒸发器冷凝侧管内流动阻力计算进行了总结与分析。
针对6种不同流程，在质量守恒和热量守恒方程的基础上，建立了包括蒸发器、冷凝器、预热器、闪蒸罐和喷射器在内的带热压缩的低温多效蒸发海水淡化系统的数学模型。采用基于高斯-约旦消元法的等面积迭代方法对带热压缩的低温多效蒸发海水淡化系统的数学模型进行了求解；利用Visual Basic语言编制了带热压缩的低温多效蒸发海水淡化系统的计算求解程序，该程序针对6种不同的流程既可以进行设计计算也可以进行校核计算，具有良好的通用性和可再植入性且界面友好。
利用求解结果，针对进口海水温度、第一效加热蒸汽温度、系统浓缩比、电厂抽汽参数、外界热源预热量以及预热位置、热压缩布置形式等参数对系统性能的影响进行了分析与比较，同时分别针对串联和并联流程、有热压缩和无热压缩的低温多效海水淡化系统方案进行分析。比较了带热压缩的6种低温多效海水淡化的流程，综合考虑，并联4+2流程的综合性能较好，其结果可以指导工程设计与实际运行。
As MED-TVC(low-temperature multi-effect distillation with thermal vapor compression)has some technical advantages through the possibility of utilizing low temperature waste heat sources, increasing gained output ratio and reducing water cost, it was studied In the dissertation .
The heat transfer coefficients inside and outside the horizontal tube were summarized. Not only the effects of tube diameter, inlet vapor velocity, steam condensing temperature and outlet vapor quality on the inside heat transfer coefficient, but also the effect of overall heat transfer temperature difference and flow density on the outside heat transfer coefficient were studied and compared. On these basis, the overall heat transfer coefficient was calculated in terms of different fouling resistance.
Based on the mass and energy equations, the physical model and mathematic model of 6 different kinds of MED-TVC was established. Equal-area design method the mathematic model was solved through Equal-area design method combined Gauss-Jordan elimination. By using Visual Basic programming language, the MED-TVC calculation software was worked out which had better generality, friendly interface and re-embeddability. Both design calculation and check calculation can be done by the software.
The effect of the feed seawater temperature, the heating steam temperature of NO.1 evaporator, the concentration ration, the steam extraction, the quantity and location of preheat flow, the form of TVC on performance of a distiller is discussed. Not only serial flow and parallel flow, but also system with and without TVC was compared. Synthetically, 4+2 parallel flow showed the best performance among the 6 flows.The conclusions provide a significant guidance in the specific extent of engineering.
针对海水淡化系统横管降膜蒸发器，分别总结了管内冷凝侧与管外蒸发侧的换热系数关联式，比较了管内径、入口蒸汽流速、蒸汽冷凝温度、出口蒸汽干度对管内蒸汽冷凝侧换热系数的影响；研究了传热温差以及喷淋密度对管外蒸发侧换热系数的影响。结合不同的污垢系数，进行了总传热系数的影响因素分析。同时对横管降膜蒸发器冷凝侧管内流动阻力计算进行了总结与分析。
针对6种不同流程，在质量守恒和热量守恒方程的基础上，建立了包括蒸发器、冷凝器、预热器、闪蒸罐和喷射器在内的带热压缩的低温多效蒸发海水淡化系统的数学模型。采用基于高斯-约旦消元法的等面积迭代方法对带热压缩的低温多效蒸发海水淡化系统的数学模型进行了求解；利用Visual Basic语言编制了带热压缩的低温多效蒸发海水淡化系统的计算求解程序，该程序针对6种不同的流程既可以进行设计计算也可以进行校核计算，具有良好的通用性和可再植入性且界面友好。
利用求解结果，针对进口海水温度、第一效加热蒸汽温度、系统浓缩比、电厂抽汽参数、外界热源预热量以及预热位置、热压缩布置形式等参数对系统性能的影响进行了分析与比较，同时分别针对串联和并联流程、有热压缩和无热压缩的低温多效海水淡化系统方案进行分析。比较了带热压缩的6种低温多效海水淡化的流程，综合考虑，并联4+2流程的综合性能较好，其结果可以指导工程设计与实际运行。
As MED-TVC(low-temperature multi-effect distillation with thermal vapor compression)has some technical advantages through the possibility of utilizing low temperature waste heat sources, increasing gained output ratio and reducing water cost, it was studied In the dissertation .
The heat transfer coefficients inside and outside the horizontal tube were summarized. Not only the effects of tube diameter, inlet vapor velocity, steam condensing temperature and outlet vapor quality on the inside heat transfer coefficient, but also the effect of overall heat transfer temperature difference and flow density on the outside heat transfer coefficient were studied and compared. On these basis, the overall heat transfer coefficient was calculated in terms of different fouling resistance.
Based on the mass and energy equations, the physical model and mathematic model of 6 different kinds of MED-TVC was established. Equal-area design method the mathematic model was solved through Equal-area design method combined Gauss-Jordan elimination. By using Visual Basic programming language, the MED-TVC calculation software was worked out which had better generality, friendly interface and re-embeddability. Both design calculation and check calculation can be done by the software.
The effect of the feed seawater temperature, the heating steam temperature of NO.1 evaporator, the concentration ration, the steam extraction, the quantity and location of preheat flow, the form of TVC on performance of a distiller is discussed. Not only serial flow and parallel flow, but also system with and without TVC was compared. Synthetically, 4+2 parallel flow showed the best performance among the 6 flows.The conclusions provide a significant guidance in the specific extent of engineering.
引文
[1] 何季民．我国海水淡化事业基本情况．电站辅机，2002，2：35-43．
[2] 中国海洋学会编．青年海洋论坛文集．北京：中国海洋出版社，1997．
[3] Wangnick K. 2004 IDA worldwide desalting plants inventory Report No. 18.
[4] 王世昌．人类需要海水淡化技术．国际学术动态，北京，1997，1．
[5] Zahid Amjad著．殷琦耀祖译．反渗透膜技术．北京：水化学和工业应用化学工业出版社，1999．
[6] Costas Pappas. The Value of Water in the 21st Century. IDA World Congress on Desalination and Water Reuse. SAN DIEGO, CALIFORNIA U. S. A.: 1999.
[7] 高从堦．海水淡化．海洋高薪技术产业化高级论坛，容城，2000．
[8] International Atomic Energy Agency. General Conference GC(ⅩⅩⅩⅪ), 1990: 928.
[9] Corrado Sammariva. Progress in thermal desalination. IDA World Congress on Sandiego, Carlifornia, USA, 2000.
[10] U. Fisher, A. Gendel. Single and dual purose desalination plants. IDA World Congress on Desalination and Water Reuse, Washington D. C., 1982.
[11] Sidney Loeb. The Loeb-Sourirajan membrane: How it came about. Desalination & Water Reuse, 1991, 3(2): 10-15.
[12] Sourirajan S. Reverse Osmosis. London: Logos Press, 1970.
[13] 林斯清．海水反渗透淡化技术现状及未来．海水利用技术研讨会论文集，北京，1998年．
[14] 国际脱盐协会数据库(IDA Database)，网站http://www.ida.com./
[15] Eli Oklejas. Energy efficiency conciderations for RO plants: a method for evalution. IDA World Congress on Desalination and Water Reuse, Washington D. C., 1991.
[16] John P. Macharg. The evolution of SWRO energy-recovery systems. IDA World Congress on Desalination and Water Reuse, Washington D. C., 1991.
[17] Adil Al-Radif. Desalination. 1993, 93: 119-125
[18] Darwish M A, Al Najem N M. Desalination. 1987, 64: 83
[19] 张维润等．电渗析工程学．北京：科学出版社，1995：100．
[20] R Rautenbach, J Widua, S Schafer. Refections on desalination processes for the 21st century. Proceedings of the IDA world congress on desalination and water sciences, Abu Dhabi, UAE, 1995: 117-136.
[21] M A Darwish, H T El-Dessouky. The heat recovery thermal vapor-compression desalting system: a comparison with other thermal desalination processes. Applied Thermal Engineering, 1996, 16(6): 523-537.
[22] 王世昌．蒸馏法发展十年．水处理技术．1985，11(5)：48-53．
[23] 张洪．多级闪蒸在水处理及工业废液蒸发方面的应用．水处理技术．1984，10(4)：28-32．
[24] Zhanghong et al, The growth of MSF in China. D & WR. 1999, 4(1): 15-21.
[25] 周少祥等．天津市研制出百吨级蒸馏装置．水处理技术．1982，1(1)：33-38．
[26] 大连市多级多效蒸馏法海水淡化会战组．多级多效蒸馏海水淡化小型实验研究-蒸发工艺试验．水处理技术．1978，4(1)：12-17．
[27] 周少祥，胡三高．1200吨／日MSF中式装置及其运行调试．庆祝中国海水淡化与水再利用学会成立十周年论文报告会．青岛，2001．
[28] 徐克俊．引进美国日产3000吨多级闪蒸海水淡化装置的设备特点，工艺流程及调试状况综述．天津市节水处理技术研讨会．天津，1991．
[29] 阮国岭．海水淡化及其在电厂中的应用．电力设备，2006，7(9)：1-5．
[30] 天津海水淡化与综合利用研究所．低温压汽蒸馏海水淡化技术研究．国家重点科技攻关计划专题研究报告，2000．
[31] 谭永文等．嵊山500吨／日反渗透海水淡化示范工程．工业水处理和海水淡化技术应用与发展研讨会．北京，1999．
[32] 国家海洋局第二海洋研究所．西沙日产二百吨淡水电渗析海水淡化装置现场运行报告．水处理技术，1982，1(1)：16-21．
[33] 第二海洋研究所西沙工程电器小组．西沙大型电渗析器海水淡化装置产品水的浓度调节．水处理技术，1982，4(2)：38-42．
[34] Chato, J. C.. Laminar Condensation inside Horizontal and Inclined Tubes. ASHRAE J., 1962, Feb, 52-60.
[35] 卓宁，孙家庆，《工程对流换热》。机械工业出版社，1991．
[36] M. M. SHAH. A General Correlation for Heat Transfer During Film Condensation Inside Pipes. Int. J. Heat Mass Transfer, 1979, Vol.22, 547-556.
[37] Li Xu, Shiyong Wang, Shichang Wang, Yuxin Wang. Studies on heat-transfer film coefficients inside a horizontal tube in falling film evaporators. Desalination, Vol.166, 2004, 215-222.
[38] Chun, K. R., Seban, R. A. Performance of prediction of falling film evaporators. ASME Journal of heat transfer, Vol.94, 432: 436
[39] 许莉，王世昌，王宇新，凌毅，水平管外壁薄膜蒸发侧表面传热系数。化工学报，55(1)，2004，19-24．
[40] 陈之航，曹柏林，赵在三，气液双相流动和传热。机械工业出版社，1983。
[41] 徐济鋆，贾斗南，沸腾传热与气液两相流。原子能出版社，2000。
[42] 刘巍，冷换设备工艺计算手册。中国石化出版社，2003。
[43] J Mitrovic. Influence of tube spacing and flow rate on heat transfer from a horizontal tube to a falling liquid film. Proceedings of the eighth international heat transfer conference, San Francisco, 1986, 4: 1949-1956.
[44] X Hu, A M Jacobi. The intertube falling film: Part 1. flow characteristics, mode transitions, and hysteresis. Heat Transfer, 1996, 118: 616-625.
[45] A B Berezin, V L Podberezney, V B Chemozubov. Investigation of heat transfer in a film horizontal tube evaporator for sea water. Proceedings of 6th int. Sym. Fresh water from the sea, Las palmas, 1978, 2: 97-104.
[46] V G Rifert, A I Sardak, A I Sardak, V L Podbereznyj. Heat exchange at dropwise condensation in heat exchangers of desalination plants. Desalination, 1989, 74: 373-382.
[47] 王培红．热能转换过程中水和水蒸汽性质计算模型．汽轮机技术，1993，35(3)：31-38．
[48] S Hennig, K Wangnick. Comparison of different equations for the calculation of heat transfer coefficients in MSF evaporators. Abu-Dhabi, UAE: IDA World Congress on Desalination and Water Sciences, 1995: 515-524.
[49] 谭浩强等．Visual Basic程序设计教程．北京：清华大学出版社，2000．
[50] 阮奇等．复杂并流多效蒸发系统的数学模型与矩阵解法．中国工程科学．2001，3(4)：36-41．
[51] 何光渝．Visual Basic常用数值算法集．北京-科学出版社，2002．
[2] 中国海洋学会编．青年海洋论坛文集．北京：中国海洋出版社，1997．
[3] Wangnick K. 2004 IDA worldwide desalting plants inventory Report No. 18.
[4] 王世昌．人类需要海水淡化技术．国际学术动态，北京，1997，1．
[5] Zahid Amjad著．殷琦耀祖译．反渗透膜技术．北京：水化学和工业应用化学工业出版社，1999．
[6] Costas Pappas. The Value of Water in the 21st Century. IDA World Congress on Desalination and Water Reuse. SAN DIEGO, CALIFORNIA U. S. A.: 1999.
[7] 高从堦．海水淡化．海洋高薪技术产业化高级论坛，容城，2000．
[8] International Atomic Energy Agency. General Conference GC(ⅩⅩⅩⅪ), 1990: 928.
[9] Corrado Sammariva. Progress in thermal desalination. IDA World Congress on Sandiego, Carlifornia, USA, 2000.
[10] U. Fisher, A. Gendel. Single and dual purose desalination plants. IDA World Congress on Desalination and Water Reuse, Washington D. C., 1982.
[11] Sidney Loeb. The Loeb-Sourirajan membrane: How it came about. Desalination & Water Reuse, 1991, 3(2): 10-15.
[12] Sourirajan S. Reverse Osmosis. London: Logos Press, 1970.
[13] 林斯清．海水反渗透淡化技术现状及未来．海水利用技术研讨会论文集，北京，1998年．
[14] 国际脱盐协会数据库(IDA Database)，网站http://www.ida.com./
[15] Eli Oklejas. Energy efficiency conciderations for RO plants: a method for evalution. IDA World Congress on Desalination and Water Reuse, Washington D. C., 1991.
[16] John P. Macharg. The evolution of SWRO energy-recovery systems. IDA World Congress on Desalination and Water Reuse, Washington D. C., 1991.
[17] Adil Al-Radif. Desalination. 1993, 93: 119-125
[18] Darwish M A, Al Najem N M. Desalination. 1987, 64: 83
[19] 张维润等．电渗析工程学．北京：科学出版社，1995：100．
[20] R Rautenbach, J Widua, S Schafer. Refections on desalination processes for the 21st century. Proceedings of the IDA world congress on desalination and water sciences, Abu Dhabi, UAE, 1995: 117-136.
[21] M A Darwish, H T El-Dessouky. The heat recovery thermal vapor-compression desalting system: a comparison with other thermal desalination processes. Applied Thermal Engineering, 1996, 16(6): 523-537.
[22] 王世昌．蒸馏法发展十年．水处理技术．1985，11(5)：48-53．
[23] 张洪．多级闪蒸在水处理及工业废液蒸发方面的应用．水处理技术．1984，10(4)：28-32．
[24] Zhanghong et al, The growth of MSF in China. D & WR. 1999, 4(1): 15-21.
[25] 周少祥等．天津市研制出百吨级蒸馏装置．水处理技术．1982，1(1)：33-38．
[26] 大连市多级多效蒸馏法海水淡化会战组．多级多效蒸馏海水淡化小型实验研究-蒸发工艺试验．水处理技术．1978，4(1)：12-17．
[27] 周少祥，胡三高．1200吨／日MSF中式装置及其运行调试．庆祝中国海水淡化与水再利用学会成立十周年论文报告会．青岛，2001．
[28] 徐克俊．引进美国日产3000吨多级闪蒸海水淡化装置的设备特点，工艺流程及调试状况综述．天津市节水处理技术研讨会．天津，1991．
[29] 阮国岭．海水淡化及其在电厂中的应用．电力设备，2006，7(9)：1-5．
[30] 天津海水淡化与综合利用研究所．低温压汽蒸馏海水淡化技术研究．国家重点科技攻关计划专题研究报告，2000．
[31] 谭永文等．嵊山500吨／日反渗透海水淡化示范工程．工业水处理和海水淡化技术应用与发展研讨会．北京，1999．
[32] 国家海洋局第二海洋研究所．西沙日产二百吨淡水电渗析海水淡化装置现场运行报告．水处理技术，1982，1(1)：16-21．
[33] 第二海洋研究所西沙工程电器小组．西沙大型电渗析器海水淡化装置产品水的浓度调节．水处理技术，1982，4(2)：38-42．
[34] Chato, J. C.. Laminar Condensation inside Horizontal and Inclined Tubes. ASHRAE J., 1962, Feb, 52-60.
[35] 卓宁，孙家庆，《工程对流换热》。机械工业出版社，1991．
[36] M. M. SHAH. A General Correlation for Heat Transfer During Film Condensation Inside Pipes. Int. J. Heat Mass Transfer, 1979, Vol.22, 547-556.
[37] Li Xu, Shiyong Wang, Shichang Wang, Yuxin Wang. Studies on heat-transfer film coefficients inside a horizontal tube in falling film evaporators. Desalination, Vol.166, 2004, 215-222.
[38] Chun, K. R., Seban, R. A. Performance of prediction of falling film evaporators. ASME Journal of heat transfer, Vol.94, 432: 436
[39] 许莉，王世昌，王宇新，凌毅，水平管外壁薄膜蒸发侧表面传热系数。化工学报，55(1)，2004，19-24．
[40] 陈之航，曹柏林，赵在三，气液双相流动和传热。机械工业出版社，1983。
[41] 徐济鋆，贾斗南，沸腾传热与气液两相流。原子能出版社，2000。
[42] 刘巍，冷换设备工艺计算手册。中国石化出版社，2003。
[43] J Mitrovic. Influence of tube spacing and flow rate on heat transfer from a horizontal tube to a falling liquid film. Proceedings of the eighth international heat transfer conference, San Francisco, 1986, 4: 1949-1956.
[44] X Hu, A M Jacobi. The intertube falling film: Part 1. flow characteristics, mode transitions, and hysteresis. Heat Transfer, 1996, 118: 616-625.
[45] A B Berezin, V L Podberezney, V B Chemozubov. Investigation of heat transfer in a film horizontal tube evaporator for sea water. Proceedings of 6th int. Sym. Fresh water from the sea, Las palmas, 1978, 2: 97-104.
[46] V G Rifert, A I Sardak, A I Sardak, V L Podbereznyj. Heat exchange at dropwise condensation in heat exchangers of desalination plants. Desalination, 1989, 74: 373-382.
[47] 王培红．热能转换过程中水和水蒸汽性质计算模型．汽轮机技术，1993，35(3)：31-38．
[48] S Hennig, K Wangnick. Comparison of different equations for the calculation of heat transfer coefficients in MSF evaporators. Abu-Dhabi, UAE: IDA World Congress on Desalination and Water Sciences, 1995: 515-524.
[49] 谭浩强等．Visual Basic程序设计教程．北京：清华大学出版社，2000．
[50] 阮奇等．复杂并流多效蒸发系统的数学模型与矩阵解法．中国工程科学．2001，3(4)：36-41．
[51] 何光渝．Visual Basic常用数值算法集．北京-科学出版社，2002．