海水淡化浓海水用于电解制氯试验

海水直接用于电解制氯存在有效氯产率低和电流效率低等问题,而水电联产海水淡化装置排放的浓海水温度和盐度均高于海水,应有利于电解制氯。为此,进行了动态对比模拟试验,将浓海水和海水作为原料水分别通入小型次氯酸钠发生器,测定有效氯产率和电流效率,观察、分析试验装置的结垢及酸洗情况。试验结果表明,浓海水较海水能够有效提高试验装置的有效氯产率和电流效率,电解浓海水产生的较多盐垢可以通过盐酸清洗而彻底去除。试验为提高次氯酸钠发生装置的电解效率以及浓海水的工业化应用提供了一条可行的技术路径。     

电厂低温多效海水淡化系统优化设计

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,可以较大的提高造水比,有效降低制水成本。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,并以法国SIDEM公司4效低温多效海水淡化装置为基础提出了新的带热压缩的低温多效蒸发海水淡化系统,并得到了给定初参数下该系统的最优设计。     

船用海水淡化装置监控系统的模块化设计

根据船用真空蒸馏式海水淡化装置的运行特点,开发出一套可视化监控系统,可以对整个装置的状态及工作参数进行动态实时监测。尤其采用了独特的前馈反馈控制方式,对该系统的产水量控制单元进行了重点模块化分析。只要把采集和分析的数据经扩充和修改,就可以将所开发的监控系统应用在其它类型海水淡化装置上。     

Potential for desalination using lower critical solution temperature polymers: Concentration of salt solutions by pluronic PE6200

A commercially available lower critical solution temperature (LCST) polymer was demonstrated to preferentially adsorb water containing a reduced ion concentration, from CrCl₃ salt solutions and release some of this scavenged water at higher temperatures. The scavenging ability of the polymer was demonstrated to be dependent on the bulk salt concentration. The volume of water scavenged and the concentration of the remaining CrCl₃ solution increased linearly with the amount of LCST polymer (Pluronic PE 6200) used. Both the volume of water removed and the amount by which the remaining CrCl₃ solution was concentrated decreased with increasing CrCl₃ concentration. Implications for research into a novel method for sea water desalination are addressed. We also show water extraction from dilute sodium chloride and sea water, and that these results are consistent with the CrCl₃ model system. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

A computer simulation of batch ion exchange membrane electrodialysis for desalination of saline water

A computer simulation program is developed for predicting desalinating performance of a batch electrodialysis process. The program includes the principle of ① mass transport, ② current density distribution, ③ cell voltage, ④ mass balance/energy consumption and ⑤ limiting current density. In this simulation the following parameters are inputted; ① membrane characteristics such as overall transport number, overall solute permeability, overall electro-osmotic permeability, overall hydraulic permeability, direct current electric resistance etc., ② electrodialyzer specifications such as flow-pass thickness, flow-pass width and flow-pass length in a desalting cell etc. and ③ electrodialytic conditions such as voltage, electrolyte concentration in a feeding solution, linear velocity in desalting cells, standard deviation of normal distribution of solution velocity ratio etc.The following phenomena were computed and discussed; ① Changes of electrolyte concentration and current density with operation time. ② Influence of cell voltage on operation time (batch duration), water recovery and energy consumption. ③ Influence of volume of an electrolyte solution prepared at first on operation time. ④ Influence of cell voltage, electrolyte concentration and standard deviation of solution velocity ratio in desalting cells on limiting current density. ⑤ Energy consumption in a reverse osmosis process. ⑥ Excepting limiting current density, the performance of an electrodialyzer is never influenced by the standard deviation of normal distribution of solution velocity ratio in desalting cells. ⑦ Energy consumption in electrodialysis is less than that in reverse osmosis at feeding saline water concentration less than about 2000 mg/l.     

煤焦油原料脱水除盐过程研究及动力学模型验证

以陕西某厂中低温煤焦油为原料,考察了煤焦油脱水除盐过程中的注水洗涤温度、洗涤过程注水量、洗涤级数、洗涤停留时间、洗涤器结构、分水方式对脱水除盐效果的影响,结果表明当洗涤温度为80 ℃、洗涤工艺过程注水量为8%～15%、洗涤级数为2～4级、洗涤停留时间为0.8～1.6 min、采用高效注水洗涤构件、分水方式采用聚结分离方式时,能够取得最佳的脱水除盐效果。建立了煤焦油脱水除盐动力学模型,用Matlab软件拟合出煤焦油脱水除盐过程的动力学参数,并采用实验数据对模型进行了验证,结果表明高效聚结分离器分水的实测值与模型预测值拟合度较好,说明该方法更适合中低温煤焦油原料的脱水除盐,可为工业应用提供参考。     

太阳能膜蒸馏系统进展与展望

海水淡化技术可有效解决现有的淡水资源短缺等问题,但受限于高成本、高能耗、低热效率等因素,传统海水淡化工艺难以进一步推广。近年来,太阳能海水淡化作为一种高效低廉的海水淡化技术正逐渐进入人们的视野,其中,太阳能膜蒸馏技术更是凭借着适用范围广、蒸发效率高、能耗低、成本低廉等诸多优点为众多学者所青睐。各国学者从宏观的系统结构到微观的光热材料等方面展开了大量的工作。但由于膜蒸馏固有的温度极化以及膜污染等问题,太阳能膜蒸馏技术仍然处于发展瓶颈中。本文按照太阳能引入膜蒸馏装置位置的不同,对现有的诸多太阳能膜蒸馏系统进行分类,并针对各类太阳能膜蒸馏系统的发展现状和技术瓶颈进行详细阐述。探讨了当前太阳能膜蒸馏技术的局限性及未来的挑战,以期为太阳能膜蒸馏系统的进一步发展及应用提供参考。     

采用增湿-去湿工艺的竖直列管式脱盐装置的实验研究

A vertical tubular desalination unit with shell and tube structure was built to perform humidification and dehumidification simultaneously on the tube and shell side of the column, respectively. The effects of several operating conditions on the productivity and thermal efficiency of the column were investigated. The results show that both the productivity and thermal efficiency of the column enhance with the elevation of the inlet water temperature. The flow rates of water and carrier gas both have optimal operating ranges, which are 10-30kg·h-1 and 4-7kg·h-1 for the present column, respectively. Meanwhile, the increase of external steam flow rate will promote the productivity of the column but reduce its thermal efficiency.     

海水淡化预处理及副产物应用的绿色化学理念

叙述一种绿色的碱絮凝海水淡化预处理技术,介绍海水淡化预处理过程中产生的新型环保材料氢氧化镁及其在环保领域的应用.例如:烟气脱硫,酸性废水的中和,处理含镍、铬、铅的工业废水.