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21.
文章介绍了兰州石化公司炼油污水深度处理反渗透(RO)系统的工艺流程及维护。通过进出水电导率、产水回收率等变化情况,分析了RO系统的运行状况。得知:运用此系统,反渗透系统产水回收率达到65%~70%,系统脱盐率在99%以上,产水可以满足一级除盐水要求,实现了装置稳定运行的目标。  相似文献   
22.
华能玉环电厂4X1000MW燃煤机组生产用水全部采用经“膜法”海水淡化技术处理的淡化海水,该淡水海水具有较强的腐蚀性,对电厂脱硫系统产生一定影响,探讨了淡化海水对脱硫系统的腐蚀及应对措施。  相似文献   
23.
电吸附技术作为高效、环境友好型的除盐、除氨氮技术,可应用与水的深度处理领域内。为了使污水回用达到工业用水的水质标准,对电吸附去除水中盐类、氨氮、COD的效果进行分析,结果表明,电吸附设备处理不同氨氮浓度的废水,对中低浓度的氨氮去除效果稳定,当进水氨氮浓度低于20 mg/L时,处理后出水氨氮浓度低于5 mg/L,COD浓度小于25 mg/L,达到回用标准;随着进水盐浓度的增大电吸附处理效果逐渐变差,在电导率低于2 500 μS/cm时除盐率在75%左右,氨氮去除率达到70%左右,COD去除率达到60%左右。经电吸附处理后的低氨氮浓度废水,TDS、氨氮浓度均可达到工业回用水标准。  相似文献   
24.
Liu, Clark C.K. and John J. Dai, 2012. Seawater Intrusion and Sustainable Yield of Basal Aquifers. Journal of the American Water Resources Association (JAWRA) 48(5): 861‐870. DOI: 10.1111/j.1752‐1688.2012.00659.x Abstract: Basal aquifers, in which freshwater floats on top of saltwater, are the major freshwater supply for the Hawaiian Islands, as well as many other coastal regions around the world. Under unexploited or natural conditions, freshwater and the underlying seawater are separated by a relatively sharp interface located below mean sea level at a depth of about 40 times the hydraulic head. With forced draft, the hydraulic head of a basal aquifer would decline and the sharp interface would move up. It is a serious problem of seawater intrusion as huge amounts of freshwater storage is replaced by saltwater. Also, with forced draft, the sharp interface is replaced by a transition zone in which the salinity increases downward from freshwater to saltwater. As pumping continues, the transition zone expands. The desirable source‐water salinity in Hawaii is about 2% of the seawater salinity. Therefore, the transition zone expansion is another serious problem of seawater intrusion. In this study, a robust analytical groundwater flow and salinity transport model (RAM2) was developed. RAM2 has a simple mathematical structure and its model parameters can be determined satisfactorily with the available field monitoring data. The usefulness of RAM2 as a viable management tool for coastal ground water management is demonstrated by applying it to determine the sustainable yield of the Pearl Harbor aquifer, a principal water supply source in Hawaii.  相似文献   
25.
ABSTRACT .Operating rule procedures are developed for the optimal use of desalination in conjunction with surface water impoundments. Results obtained from the use of hill-climbing and dynamic programming methods are compared. Benefits to be obtained from the integrated use of desalination are demonstrated through a case study for the Barcelona area of Spain.  相似文献   
26.
ABSTRACT The selection of an evaporator design must reflect the balancing of captial cost (primarily in heat exchanger surface and vessels) against operating cost (primarily steam cost) to achieve minimum cost. In a conjunctive plant the tendency is to select a low-capital cost, high-operating cost plant. In addition, it is advantageous to use a high-capacity plant which needs to be operated much less of the time than a plant which is sized just at the needed rate. For example, in the study of a possible system to satisfy a future increase of 450 MGD in water supply to New York Qty, a plant of 750 MGD capacity was selected as optimum. This plant, of the advanced VTE-MSF process type, would have a performance ratio of 9 lb product/1000 Btu as compared to 10-13 normally used for base-loaded plants. Steam would be supplied by a multi-unit dual-purpose nuclear power plant. The most economical type of energy supply would be “interruptible”; the steam would be used by a low pressure turbine to generate electricity during periods of peak electrical demand but would be available to the desalting plant at other times. The low pressure turbine would be available as spinning reserve during desalting plant operation. It is estimated that the desalting plant would have a load factor of 27 per cent over its life.  相似文献   
27.
The study contains the methodology of finding the optimal time to start the operation of a desalting plant or any other non conventional source of water for agricultural use in Israel. The essence of the methodology is the moving equilibrium price and quantity of agricultural products. The market of agricultural products is represented by a single demand curve and a supply curve which is derived from the agricultural sector production function. Both the demand for and the supply of agricultural products functions are shifting over time. The marginal value product of water is the critical value that determines the optimal time of a desalting plant. The study is static in the sense that dynamic aspects per se are not dealt with-e.g. learning by doing of building and operating desalting plants. The empirical results although used for illustrative purposes can be used as reference points for other detailed and more ‘exact’ studies on water desalination.  相似文献   
28.
从气候、淡水资源和海洋资源等方面简要介绍了山东省的水产资源自然条件,概述了主要淡水虾和海水虾的资源及其分布。从养殖规模和养殖模式两方面总结了主要经济虾类的养殖现状,指出了优质虾苗繁殖困难、病害防治水平低、产品质量差、销售渠道狭窄等制约虾类养殖业发展的主要问题,并据此提出了相应的对策。  相似文献   
29.
海水中有机污染物的气相色谱-质谱法鉴定   总被引:5,自引:0,他引:5  
本文采用一种简便的连续萃取装置.对海水中痕量有机物进行富集,大量的海水被萃取后,萃取物经干燥浓缩在毛细管气相色谱上进行了分离,并用质谱-计算机自动检索装置进行了定性鉴定,共确定出36种组分。本方法的检测限为辛烷10ppt。  相似文献   
30.
为了解秦皇岛洋戴河流域浅层地下水咸化程度,开展了野外调查和水样采集,现场测试EC、TDS指标,并对水样进行了室内水化学分析.应用层次分析法结合Arcgis对选取的6个指标(Cl离子、TDS、Li离子、钠吸附比、硝酸盐、潜在盐度)进行权重计算、归一化处理和栅格计算,得出地下水咸化等级分区(未咸化区、轻微咸化区、中等咸化区、严重咸化区).咸化最严重区域位于沿海平原,包括枣园村、王各庄村.中度咸化区部分位于沿海平原,包括都寨村、西陆庄村、蒋营村、樊各庄,主要是由海水入侵导致的;而樊各庄咸化的原因是海水入侵和工业废水的污染;其他中度咸化区位于低山丘陵区,包括大湾子村、兴隆寨村,则是由水岩作用、农业污水、生活污水造成的.轻微咸化区主要分布在中等咸化区周围,未咸化区集中在山前平原区.  相似文献   
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