全自然能源海水淡化系统

由北京理工大学研制海水淡化装置主机，重庆后勤工程学院和北京理工大学共同组织实施的全自然能源海水淡化系统在河北秦皇岛市某海军基地成功建造并实现全自动运行。     

新型平板太阳能集热器海水淡化系统研究

海水淡化是利用海水脱盐生产淡水的技术和过程。多效蒸馏海水淡化原理是高温蒸汽或热水与海水进行热交换,海水被加热,蒸发出的水蒸气冷凝得到淡水,但其结垢和腐蚀问题比较严重。低温多效蒸馏是多效蒸馏技术的一种改进技术,操作温度较低,避免和减轻了海水对设备造成的腐蚀与结垢问题,     

太阳能光热海水淡化系统应用研究

介绍太阳能光热产蒸汽系统和海水淡化系统,将高温蒸汽和海水淡化装置在集成系统中加以融合,实现一种太阳能光热海水淡化系统,并以风力发电作为辅助系统。文章以全国第一个太阳能光热海水淡化示范项目为例,对该系统进行详细的性能和效果应用分析,在该项目成功产水之后展望太阳能海水淡化今后的发展方向与前景。     

直接减压式太阳能海水淡化装置

本文介绍已获国家专利（申请号：９８２１４８９９．２）的太阳能海水淡化设备。设备利用高效太阳能集热技术加热海水,利用真空减压技术收集水蒸汽制备淡水,该设备是一种适于为缺乏淡水的海边和岛屿生活的人们提供淡水的处理设备。     

一种新型太阳能海水淡化系统的实验研究

介绍了一种新型的太阳能海水淡化方法,即结合太阳能空气集热器和太阳能热管、利用空气增湿除湿来实现海水淡化。分别进行了电吹风模拟太阳能空气集热器的蒸发器实验,以及结合3m2太阳能空气集热器和热管集热器的实际装置实验。结果表明,影响蒸发量的主要因素为热空气温度、热空气流量、初始水量、水温、出气孔直径和数量。实验结果表明,装置可获得的最大冷凝量为790g/h,计算出系统的产水率和热力学效率分别为5.59×10-5kg/kJ和12.4%。     

多级增湿太阳能海水淡化的实验研究

基于多级增湿和分级冷凝原理,设计搭建了一台新型利用太阳能的多级增湿海水淡化装置,实验研究了喷水温度、不同的空气循环方式、分级冷凝对系统产水率和热耗的影响变化规律。研究结果表明,由于采用了分级冷凝和多级增湿技术,系统产水率提高了25%～50%,产水热耗得以降低。     

吸收式太阳能海水淡化技术

介绍了吸收式太阳能海水淡化技术,简述了该技术的运行原理,分析了研究现状,总结了它的工艺特点、经济可行性以及与其他低品位能源相匹配等问题,并展望了其广阔的应用前景。     

太阳能海水淡化技术

太阳能海水淡化技术无污染、低能耗、生产规模可有机组合,是有效解决淡水危机的新途径.介绍了现有的海水淡化技术,分析了太阳能海水淡化,尤其是中高温槽式太阳能闪蒸法海水淡化系统.     

多级迭盘式太阳能海水淡化装置的性能研究与经济性分析

设计制作了一台多级迭盘式太阳能海水淡化装置。该装置通过折皱底面来强化凝结作用,利用与最下面一级相连的热管式真空管集热器供热,在天气晴朗时能够不需其他动力自动制取淡水,具有操作简单、运行可靠、维护费用低等特点。试验结果表明,该装置利用太阳能制取淡水的性能系数为1.01,是一种较理想的户用太阳能海水淡化装置。文章还对装置寿命期内的经济效益进行了分析。     

低温多效蒸发海水淡化装置的计算分析

建立了多效蒸发海水淡化装置计算模型,对串流、并流和并叉流三种不同工艺流程下的低温多效蒸发海水淡化系统进行了计算和分析。计算结果显示,对于给定的多效蒸发海水淡化装置,提高加热蒸汽温度,可大大提高装置的淡化水量,同时对加热蒸汽的需求量也增大,但造水比随加热蒸汽温度的升高呈减小趋势;就三种工艺流程而言,并叉流具有较好的热利用率。     

Feasibilty study of renewable energy powered seawater desalination technology using natural vacuum technique

With an ever-increasing population and rapid growth of industrialization, there is great demand for fresh water. Desalination has been a key proponent to meet the future challenges due to decreasing availability of fresh water. However, desalination uses significant amount of energy, today mostly from fossil fuels. It is, therefore, reasonable to rely on renewable energy sources such as solar energy, wind energy, ocean thermal energy, waste heat from the industry and other renewable sources. The present study deals with the energy-efficient seawater desalination system utilizing renewable energy sources and natural vacuum technique. A new desalination technology named Natural Vacuum Desalination is proposed. The novel desalination technique achieve remarkable energy efficiency through the evaporation of seawater under vacuum and will be described in sufficient detail to demonstrate that it requires much less electric energy compared to any conventional desalination plant of fresh water production of similar capacity. The discussion will highlight the main operative and maintenance features of the proposed natural vacuum seawater desalination technology which seems to have promising techno-economic potential providing also advantageous coupling with renewable energy sources.     

Investigation on a small-scale vertical tube evaporator multieffect desalination system: Modeling,analysis, and optimization

A growing population with depleting water resources has increased the requirement for desalination systems. Large-scale desalination plants have seen a growth in the recent period; however, the small-scale (SS) decentralized desalination plants' need has not been realized for the rural population. Low specific heat consumption for multieffect desalination systems makes it suitable for such decentralized operation. The challenge now lies in determining the system capacity and optimal operational range for the SS requirements. In this study, the thermoeconomic model for an SS multieffect desalination system for various configurations is developed. Optimization of the SS plant for the number of effects is performed to determine the optimal operational range of motive steam pressure, motive steam flow rate, and feed water flow rate. Total distillate production and freshwater cost are focused on objectives and constraints imposed over the input parameters with SS production. The results reveal that for a distillate production of 750 L/day, the motive steam flow requirement is estimated to be 25–35 kg/h with a pressure range of 2–5 bar. This study provided an overview for selecting the number of effects based on the commercial aspect of total production requirements.     

Experimental study of a solar desalination pond as second stage in proposed zero discharge desalination process

This work represents the efficiency of a solar desalination pond as a second stage of proposed zero discharge desalination processes to reach fresh water and also concentrated brine from the effluent wastewater of the desalination unit of Mobin petrochemical complex. So a solar desalination pond is constructed after a pretreatment unit to concentrate the softened wastewater to about 20 wt%. The concentrated wastewater is as a suited feed for a forced circulation crystallizer. During one year, the effects of major parameters such as ambient temperature and solar insolation rate are investigated, experimentally. specific gravity in each layer of concentrated brine wastewater is evaluated. Also, evaporation rates are calculated theoretically and are verified by experimental data. Theoretical values predict evaporation rate accurately. Results show good agreement with experimental data. According to results, maximum evaporation rate is 5 l/m² day when the insolation rate is about 24,602 kJ/m² day Solar energy absorption factor on June is max. Also, experimental results show the best proposed time to gain highest thermal energy is on spring therefore performance efficiency of solar desalination pond promote on spring comparing with the other months. Extracted data for specific gravity prove the bottom of solar desalination pond, layer 1, is best zone for energy saving and energy utilization.Also, theoretical values of evaporation rate are calculated according to measured temperatures and related mass conservation equation. Comparison between theoretical and experimental values shows dusty weather, humidity and wind velocity affects on heat transfer coefficients approximately. So, deviations between theoretical data and measured values can be explained. Results show good agreements with experimental data.     

真空法制取冰浆的实验分析与研究

本文通过分析总结,构建真空法制取冰浆实验的总体布局,建立可视化的真空法制取冰浆的实验台。通过改变水滴初温与真空罐内初始压力,对真空制取冰浆的方法进行了实验研究。实验表明,初始压力对冰浆生成率的影响更大。     

Wastewater desalination system utilizing a low‐temperature heat pump

A wastewater desalination system based on a low‐temperature air source heat pump was developed and studied in this paper. The system consists of 2 main parts: the wastewater flow process and the heat pump cycle. A series of experiments were conducted on the system under different conditions, and the effect of the evaporation temperature was investigated. This system can reach equilibrium at any evaporation temperature using the combination of the compressor and vacuum pump. To treat wastewater with low boiling point organic matter, the system was operated at a low evaporation temperature of 48°C. The organic matter remained in the concentrated wastewater, and the organic removal was approximately 97%. Three kilograms of treated water was produced in 1 hour with an energy consumption of 250 W. The performance ratio (PR) obtained from the experiments ranged from 4.6 to 7.3. The cost for treating 1 kg of water was 0.038 yuan CNY assuming 0.5 yuan CNY per kWh at the compressor frequency of 50 Hz.     

Thermoeconomic analysis of a low-temperature multi-effect thermal desalination system coupled with an absorption heat pump

This study presents a thermal and economic performance analysis of a LT-MEE (low-temperature multi-effect evaporation) water desalination system coupled with an LiBr-H₂O ABHP (absorption heat pump). A 60-78% water production increase over a stand-alone LT-MEE run at the same heat source conditions can be obtained owing to the coupling. A detailed thermodynamic sensitivity analysis of the ABHP-MEE is performed. Although ABHP is usually considered to be more efficient than an EHP (ejector heat pump), we also compare the thermal performance of the ABHP-MEE with an integrated EHP-MEE system. The results show that the ABHP has a more favorable thermal performance than the EHP only in certain parameters ranges. The reasons and these parameters ranges are discussed. The economic analysis of the ABHP-MEE shows that the capital cost of the ABHP accounts for a very small part of the water cost, and when designing an ABHP for an existing MEE unit, the parameters selection of an ABHP for lower water cost is consistent with that for better thermal performance. The unit steam cost is an important factor in determining whether the ABHP-MEE or the EHP-MEE is economically favorable, with the influence discussed. Also, a recommended general procedure for economic comparison between ABHP-MEE and EHP-MEE is outlined.     

The thermal characteristics and economic analysis of a solar pond coupled low temperature multi stage desalination plant

The paper discusses optimisation of the size of the pond and the number of stages for three different storage zone temperatures taking into account the large variation in quantity of energy supplied by the pond between summer and winter. One result is that over-sizing the pond, leading to some rejection of the heat collected during the summer (which is referred to as peak clipping), will result in a higher utilisation factor of the desalination plant and a reduction in the summer/winter yield ratio. Optimum peak clipping days, leading to the minimum product water cost, for each storage zone temperature and performance ratio is presented.The sensitivity analysis of the various factors affecting the overall water costs show that the capital costs comprise about two thirds (2/3) of the total desalinated water costs. This demonstrates and re-emphasises the inherent and basic fact that solar desalination is a capital intensive enterprise. Each 1% increase in interest rate increases solar pond thermal energy costs by about 13-15% and desalinated water costs from SP/MSF combination by about 10-13%.     

Experimental study of an innovative solar water desalination system utilizing a passive vacuum technique

A solar desalination system based on an innovative passive vacuum concept, utilizing low-grade solar heat, was studied experimentally. The system uses the natural means of gravity and atmospheric pressure to create a vacuum, under which liquid can be evaporated at much lower temperatures and with less energy than conventional techniques. A vacuum equivalent to 3.7 kPa (abs) or less can be created depending on the ambient temperature at which condensation will take place. The system consists of a heat source, an evaporator, a condenser, and injection, withdrawal and discharge pipes. The effect of various operating conditions (withdrawal rate, depth of water body and temperature of the heat source) were studied experimentally and compared with theoretical results. The experimental results agreed well with the theoretical predictions. It was found that the effects of withdrawal rate and the depth of water in the evaporator were small while the effect of heat source temperature was significant.     

小型太阳能海水淡化装置

基于空气增湿-除湿海水淡化技术,采用热海水与空气逆流对喷的空气加湿器,设计了结合太阳能集热器的小型太阳能海水淡化系统。试验结果表明,该结构的空气加湿器具有很好的加湿效果,出口空气相对湿度可达到98%以上。当喷水温度为60℃、空气流量为11.8 L/s时,该小型海水淡化装置产水率可达3.42 kg/h。