机械蒸汽再压缩(MVR)蒸发系统性能研究
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AThesisSubmitted to
NanjingTechUniversity
For the AcademicDegreeofMasterof
Engineering
BY
Chengzhen Gu
Supervised by
Prof. Housheng Hong
April 2015
学位论文独创性声明
本人声明所呈交的学位论文是我个人在导师指导下进行的研究工作及取得的研究成果。尽我所知，除了文中特别加以标注和致谢的地方外，论文中不包含其他人已经发表或撰写过的研究成果，也不包含为获得南京工业大学或其它教育机构的学位或证书而使用过的材料。与我一同工作的同志对本文所做的任何贡献均已在论文中作了明确的说明并表示了谢意。
根据实际工业生产的需要，初步设计了蒸发量为1000kg/h工业级MVR系统，详述了具体工况的能量转变和单体设备规模。通过与三效蒸发器在能耗上的理论对比，MVR系统每年可节约运行成本40万元，能源效益上可节能74%。
关键词：机械蒸汽再压缩能耗蒸发量单位能耗蒸发量Aspen plus
A
The world today is facing both severe energy crisis and environmental crisis. The total energy is shortage, which seriously constrains the rapid development of China`s national economy and the ቤተ መጻሕፍቲ ባይዱountry has been advocating energy saving production methods. Concentrated by evaporation process which is a very energy-intensive production processes ,and is widely used in dyeing and finishing ,paper making, chemical engineering, pharmaceutical and food industries. Therefore, it is necessary to develop a new evaporation plant which is low energy consumption, low operating costs and a high degree of automation.
□2、本论文已经通过保密申请，请保留三年后按照第一项公开（打钩生效）
□3、本论文已经通过校军工保密申请，不予公开（打钩生效）
研究生签名：导师签名：
日期：日期：
摘要
能源和环境危机是当今世界的难题，能源总量的供不应求严重制约着我国经济的快速发展，国家也一直倡导节能减排的生产方式。其中蒸发浓缩过程是十分耗能的一道生产工序，并广泛应用在印染、造纸、化工、医药和食品等行业。研究设计出一种能耗少、运行费用低和自动化程度高的新蒸发设备具有重要的现实意义。
分类号密级
U D C编号
硕士学位论文
机械再压缩蒸发系统的研究开发
研究生姓名： 顾承真
导师姓名：洪教授
申请学位级别： 硕士
一级学科名称：化学工程与技术
二级学科名称：生物化工
2015年4月
Research and development of Mechanical Vapor Recompression system
设计了蒸发量为150kg/h的水蒸发体系的MVR实验平台，其中降膜蒸发器的蒸发面积为10m2，选用了功率为18kw的罗茨压缩机作为蒸汽压缩机，同时也设计气液分离器、储罐和管道的大小。实验中以总蒸发水量和单位能耗蒸发水量作为MVR蒸发系统的性能指标，分别研究了进料温度、蒸发压强、压缩机频率对其影响。结果表明：最佳进料温度是蒸发压强下的饱和液体温度;最适蒸发压强与具体系统的蒸发能力和压缩机效率密切有关，在压缩机效率保持较高水平的前提下，适当降低蒸发压强有利于系统的节能；压缩机的频率直接影响系统的蒸发量和压缩机的功耗，在压缩机允许的范围内增大压缩机频率，单位能耗蒸发量是增加的；实测的MVR在蒸发压强为86kPa时，系统的能耗只有理论三效蒸发器的最低能耗的46%。
This paper established a MVR evaporation process flow that can fully use energy. Quality and energy of each operation node were calculated，and a system of simulation process was establish using the Aspen Plus software. This research investigated the mass flow of cyclic steam and the mass flow of added water under different feed temperatures, condensation temperatures，the ratio of vapor compression and evaporation pressure，by analyzing controlling unit operations. The results in theory showed that: (1) raw materials reached the optimal conditions in saturated liquids or slightly overheated. (2) the vapor compression ratio of compressor in the 1.8—2.2 was more reasonable. (3) The vaporpressureof MVR system shouldbe combined with specific heat-sensitive products as much as possible at a relatively low evaporationpressure.(4) The condensate is preferably discharged in the saturated liquid.
研究生签名：日期：
学位论文的使用声明
□1、南京工业大学、国家图书馆、中国科学技术信息研究所、万方数据电子出版社、中国学术期刊（光盘版）电子杂志社有权保留本人所送交学位论文的复印件和电子文档，可以采用影印、缩印或其他复制手段保存论文并通过网络向社会提供信息服务。论文的公布（包括刊登）授权南京工业大学研究生部办理。（打钩生效）
MVR experimental platform which can handle 150kg/h water evaporation is designed ,where falling film evaporator having an evaporation area of 10m2. Root compressor is selected as a vapor compressor which own power of 18kw,also design gas-liquid separator ,tanks and piping size. This paper investigated that feed temperature, evaporation pressure and compressor frequency how to affectevaporation of the total amount of water evaporationandspecific moisture extraction rater (SMER), which is as performance indicators of MVR. The results show that: the optimum temperature of the feed is a saturated liquid temperature at the evaporator pressure. the optimum evaporation pressure based on evaporation capacity and compressor efficiency which Closely related to the specific system. While maintaining a high level of efficiency of the compressor,the evaporator pressure is suitably in favor of energy saving. Frequency of the compressor directly affect evaporation of the total amount of water and compressor power,SMER is increasing when improve the frequency of the compressor within the allowable range.The energy consumption of the system, measured at 86kPa of evaporator pressure, onlyoccupytheoretical minimum energy consumption of 46%compared to the three-effect evaporation.
机械蒸汽再压缩（Mechanical Vapor Recompression，简称MVR）蒸发技术因热量的重复利用和提高能源效率的特点，被认为是当今世界最节能的蒸发方式。其原理是：溶液在蒸发器内受热产生的二次蒸汽经蒸汽压缩机的作用，使蒸汽的温度、压力和热焓增加，重新作为系统的热源使用。物料吸收蒸汽的冷凝潜热并继续产生二次蒸汽，二次蒸汽再次被压缩利用，这样物料持续蒸发，系统只需要消耗压缩机的功耗便可完成蒸发工段。
Mechanical Vapor Recompression (MVR), which has been considered one of the most energy-efficient evaporation, help to reuse heat and improve energy efficient. The theory is that the secondary steam created by evaporator is recompressed by compressor, the pressure , temperature and enthalpy of the vapor is higher, and can be used as the heat source to heat system itself. Materials absorbs heat because of condensation of steam, and water in the materials becomes vapor because of endotherm. The secondary steam is compressed and used again, so the materials continued to evaporate. Hence, the system only demands of energy from the compressor.
本文建立了一套充分利用热源的MVR蒸发工艺流程，并通过理论分析对每个操作节点进行了质量和能量衡算，同时利用Aspen Plus模拟软件建立了系统的流程模拟图。通过对操作单元的变量控制，研究了二次蒸汽循环量、补充水的量与进料温度、冷凝液温度、蒸汽压缩比以及蒸发压强等之间的变化关系。理论上得出的结论有：1.原料进入蒸发器前应先预热至饱和液体或微过热状态。2.二次蒸汽在压缩阶段，压缩比在1.8—2.2时节能效果最佳3. MVR热泵系统蒸发压强应结合具体产品的热敏性，尽可能控制在较低的蒸发压强。4.蒸汽冷凝液在饱和液体下排出较好。
NanjingTechUniversity
For the AcademicDegreeofMasterof
Engineering
BY
Chengzhen Gu
Supervised by
Prof. Housheng Hong
April 2015
学位论文独创性声明
本人声明所呈交的学位论文是我个人在导师指导下进行的研究工作及取得的研究成果。尽我所知，除了文中特别加以标注和致谢的地方外，论文中不包含其他人已经发表或撰写过的研究成果，也不包含为获得南京工业大学或其它教育机构的学位或证书而使用过的材料。与我一同工作的同志对本文所做的任何贡献均已在论文中作了明确的说明并表示了谢意。
根据实际工业生产的需要，初步设计了蒸发量为1000kg/h工业级MVR系统，详述了具体工况的能量转变和单体设备规模。通过与三效蒸发器在能耗上的理论对比，MVR系统每年可节约运行成本40万元，能源效益上可节能74%。
关键词：机械蒸汽再压缩能耗蒸发量单位能耗蒸发量Aspen plus
A
The world today is facing both severe energy crisis and environmental crisis. The total energy is shortage, which seriously constrains the rapid development of China`s national economy and the ቤተ መጻሕፍቲ ባይዱountry has been advocating energy saving production methods. Concentrated by evaporation process which is a very energy-intensive production processes ,and is widely used in dyeing and finishing ,paper making, chemical engineering, pharmaceutical and food industries. Therefore, it is necessary to develop a new evaporation plant which is low energy consumption, low operating costs and a high degree of automation.
□2、本论文已经通过保密申请，请保留三年后按照第一项公开（打钩生效）
□3、本论文已经通过校军工保密申请，不予公开（打钩生效）
研究生签名：导师签名：
日期：日期：
摘要
能源和环境危机是当今世界的难题，能源总量的供不应求严重制约着我国经济的快速发展，国家也一直倡导节能减排的生产方式。其中蒸发浓缩过程是十分耗能的一道生产工序，并广泛应用在印染、造纸、化工、医药和食品等行业。研究设计出一种能耗少、运行费用低和自动化程度高的新蒸发设备具有重要的现实意义。
分类号密级
U D C编号
硕士学位论文
机械再压缩蒸发系统的研究开发
研究生姓名： 顾承真
导师姓名：洪教授
申请学位级别： 硕士
一级学科名称：化学工程与技术
二级学科名称：生物化工
2015年4月
Research and development of Mechanical Vapor Recompression system
设计了蒸发量为150kg/h的水蒸发体系的MVR实验平台，其中降膜蒸发器的蒸发面积为10m2，选用了功率为18kw的罗茨压缩机作为蒸汽压缩机，同时也设计气液分离器、储罐和管道的大小。实验中以总蒸发水量和单位能耗蒸发水量作为MVR蒸发系统的性能指标，分别研究了进料温度、蒸发压强、压缩机频率对其影响。结果表明：最佳进料温度是蒸发压强下的饱和液体温度;最适蒸发压强与具体系统的蒸发能力和压缩机效率密切有关，在压缩机效率保持较高水平的前提下，适当降低蒸发压强有利于系统的节能；压缩机的频率直接影响系统的蒸发量和压缩机的功耗，在压缩机允许的范围内增大压缩机频率，单位能耗蒸发量是增加的；实测的MVR在蒸发压强为86kPa时，系统的能耗只有理论三效蒸发器的最低能耗的46%。
This paper established a MVR evaporation process flow that can fully use energy. Quality and energy of each operation node were calculated，and a system of simulation process was establish using the Aspen Plus software. This research investigated the mass flow of cyclic steam and the mass flow of added water under different feed temperatures, condensation temperatures，the ratio of vapor compression and evaporation pressure，by analyzing controlling unit operations. The results in theory showed that: (1) raw materials reached the optimal conditions in saturated liquids or slightly overheated. (2) the vapor compression ratio of compressor in the 1.8—2.2 was more reasonable. (3) The vaporpressureof MVR system shouldbe combined with specific heat-sensitive products as much as possible at a relatively low evaporationpressure.(4) The condensate is preferably discharged in the saturated liquid.
研究生签名：日期：
学位论文的使用声明
□1、南京工业大学、国家图书馆、中国科学技术信息研究所、万方数据电子出版社、中国学术期刊（光盘版）电子杂志社有权保留本人所送交学位论文的复印件和电子文档，可以采用影印、缩印或其他复制手段保存论文并通过网络向社会提供信息服务。论文的公布（包括刊登）授权南京工业大学研究生部办理。（打钩生效）
MVR experimental platform which can handle 150kg/h water evaporation is designed ,where falling film evaporator having an evaporation area of 10m2. Root compressor is selected as a vapor compressor which own power of 18kw,also design gas-liquid separator ,tanks and piping size. This paper investigated that feed temperature, evaporation pressure and compressor frequency how to affectevaporation of the total amount of water evaporationandspecific moisture extraction rater (SMER), which is as performance indicators of MVR. The results show that: the optimum temperature of the feed is a saturated liquid temperature at the evaporator pressure. the optimum evaporation pressure based on evaporation capacity and compressor efficiency which Closely related to the specific system. While maintaining a high level of efficiency of the compressor,the evaporator pressure is suitably in favor of energy saving. Frequency of the compressor directly affect evaporation of the total amount of water and compressor power,SMER is increasing when improve the frequency of the compressor within the allowable range.The energy consumption of the system, measured at 86kPa of evaporator pressure, onlyoccupytheoretical minimum energy consumption of 46%compared to the three-effect evaporation.
机械蒸汽再压缩（Mechanical Vapor Recompression，简称MVR）蒸发技术因热量的重复利用和提高能源效率的特点，被认为是当今世界最节能的蒸发方式。其原理是：溶液在蒸发器内受热产生的二次蒸汽经蒸汽压缩机的作用，使蒸汽的温度、压力和热焓增加，重新作为系统的热源使用。物料吸收蒸汽的冷凝潜热并继续产生二次蒸汽，二次蒸汽再次被压缩利用，这样物料持续蒸发，系统只需要消耗压缩机的功耗便可完成蒸发工段。
Mechanical Vapor Recompression (MVR), which has been considered one of the most energy-efficient evaporation, help to reuse heat and improve energy efficient. The theory is that the secondary steam created by evaporator is recompressed by compressor, the pressure , temperature and enthalpy of the vapor is higher, and can be used as the heat source to heat system itself. Materials absorbs heat because of condensation of steam, and water in the materials becomes vapor because of endotherm. The secondary steam is compressed and used again, so the materials continued to evaporate. Hence, the system only demands of energy from the compressor.
本文建立了一套充分利用热源的MVR蒸发工艺流程，并通过理论分析对每个操作节点进行了质量和能量衡算，同时利用Aspen Plus模拟软件建立了系统的流程模拟图。通过对操作单元的变量控制，研究了二次蒸汽循环量、补充水的量与进料温度、冷凝液温度、蒸汽压缩比以及蒸发压强等之间的变化关系。理论上得出的结论有：1.原料进入蒸发器前应先预热至饱和液体或微过热状态。2.二次蒸汽在压缩阶段，压缩比在1.8—2.2时节能效果最佳3. MVR热泵系统蒸发压强应结合具体产品的热敏性，尽可能控制在较低的蒸发压强。4.蒸汽冷凝液在饱和液体下排出较好。