外文翻译---冷却水的回收和再利用的潜力.docx

the potential for the recovery and reuse of cooling water abstractthe cooling water is the major part of industrial wateruse , either from the view of demand priority or supply volume. in order to save water, the loading of supply system can be reduced if the cooling water can be recovered and reused. for this reason, exploration of the recent operation status of the cooling water system has become essential . this study was initially focused on the current applications and reuse trends of cooling water in oil refineries, chemical industry, steel mills, food industry, electronics works, textile plants and power stations. according to the statistical analysis, the portable water and groundwater are the primary sources of makeup water for cooling systems. the multiple-chemicals method and makeup treatment are increasingly accepted for the reclamation of cooling water. on the other hand, sidestream treatment and blowdown reuse are not popular . the recovery rate of blowdown is only 26.8%. the fact of higher cost is the major reason to depress the willingness of recovery. some representative plants had been selected for case study. however, most cooling water systems are only operated by operators experience according to field investigation. in each case, the water quality indexes were used to evaluate the operational condition of cooling water systems. there was no case plant found to be operated at appropriate cycles of concentration. this paper also presented the bottlenecks of conservation technologies of cooling water. these bottlenecks include increasing the cycles of concentration, the reuse of wastewater, and the blowdown treatment for reuse. this paper also demonstrates that the recovery and reuse of cooling water has great potential and is feasible for the available technologies , but the industries are still unwilling to upgrade because of initial cost finally, some approaches associated with technology, economics, environment and policy are proposed to be a reference for the industries and the government authorities. 1999 elsevier science b.v. all rights reserved.keywords: cooling water; recovery and reuse; taiwan; makeup; blowdown1. introductionthe demand of water resource has apparently increased because of the highly economical growth, rapid industrial development and the upgrading of living standard in . the water source is difficult to develop economically due to land sinking, groundwater pollution and the difficulty of new reservoir construction. therefore, how to reclaim and reuse the water is an efficient way to solve this problem. among the industries wastewaters, the cooling water is most valuable for recovery because it has larger volume and is less contaminated. on the other hand, some industries reuse the properly treated process wastewater or domestic sewage for cooling. although the multiple chemicals dosage method is a mature technology to increase the recycling amount, the potential must be evaluated for the reuse and recovery of cooling water when enhancing the execution of reusing cooling water further. this study is interested in perceiving the matters concerned with cooling water quality, treatment technology for reclamation and the feasibility of recovery and reuse.2. the characteristic and operational problems of cooling water system the cooling water systems were divided into once through, open recirculating and closed recirculating systems. the operating problems of cooling water system are combined with corrosion, scale, fouling and slime . corrosion is induced by the electrochemical reaction and induces the weight loss of metal. the scale is formed under metal salts supersaturation, e.g. calcium, magnesium, and formed sediments on the metal surface. fouling is caused by the corrosion products or the suspended matter that is attached on the metal surface. slime is caused by the growth of microorganism which also combined microorganical fouling and corrosion, etc. the operational problems described as above are normally concerned with thecharacteristic of the cooling water system. therefore, the water quality needs to be carefully considered when reusing the cooling water. table 1 displayed the relationship between the more important water constituents and the operational problems of the cooling water system. if a cooling water system is operated under the characteristics of neutral ph, lower temperature, higher velocity, lower concentration of dissolved salts and nutrition matter, the situation of operational problems can be reduced.2.1changes over time in different locations between ammoniafig.2 variation of nh3-n in leachate with the lapsed time and the different areasfrom the figure, the overall trend curve can be seen from the more recent sampling point pollution sources, pollutants and, generally higher, close to the sand box at the bottom and away from sources of ammonia concentration at the latest sampling point, reflecting the most insensitive. as the leachate into the passage of time, changes in pollutant concentration with distance curve is also gradually move over, along with changes in the amount of leachate into the concentration of the sampling points followed by corresponding changes. at the level of ammonia migration rate decreased gradually along the flow direction, the attenuation rates were increased. ammonia used to migrate to g2 point of time of about 12d, used to reach the point of time is about k2 30d, migration rate is determined by 4cm / d down to 3.2cm / d; decay rates were higher: c2, g2, k2 three largest ammonia concentration ratio of c2: g2: k2 = 732:477:86. in the vertical, the nitrogen transfer rate along the flow direction followed by increased migration of ammonia from c3 to c1 point point of time used for the 15d so, g3 g2 g1 in the first 15d, three were detected ammonia. along the flow direction and reduce the concentration of ammonia under different mechanisms, can in turn be contaminated sand box in the halo into the transitional zone and adjust the saturation area: in the saturation region the lowest rate of nitrogen attenuator; adjust the attenuation of the region the highest rate of ammonia. at 15d, g3 g2 g1 saturation point for the transition zone, respectively, and adjust the area, three of the concentration ratio of 195:50:5, adjust the area is much larger than the decay rate of the decay rate of the saturation region. ammonium salt water environment in the underground decay, migration is mainly affected by advection, dispersion and effects with the media. because the laboratory sand box filler sand for the size of the uniform, and the packing density is uniform, the sand inside the convection has little effect on the ammonia concentration; dispersion (including proliferation) effect mainly affects the migration of nitrogen, ammonia nitrogen in the saturated district spread the fastest rate of diffusion of the slowest adjustment area; main function is the biological role of the media (mainly microbial) and abiotic effects (mainly with absorption), biological effect occurs mainly in saturated zone, unsaturated zone microorganisms most, the strongest action of microorganisms, mainly non-biological role in adjusting the area, adjusting the strongest adsorption capacity of soil.3. the bottlenecks and the potential when recovering and reusing cooling water .3.1. the bottlenecks of reco6ering and reusing cooling water in taiwan according to the above description, the bottlenecks of recovering and reusing cooling water in taiwan can be divided into three aspects . further description and discussion are derived as follows.3.1.1. the bottleneck of increasing the cycles of concentration increasing cycles of concentration can reduce blowdown volume, treatment cost and makeup water volume. the attainable technology includes the pretreatment of makeup and the treatment of recirculating water and sidestream. 3.1.2. the bottleneck of wastewater reusethe industries may reduce makeup if they reuse producing wastewater or sewage for cooling water. unfortunately, there have a rare case. it may be because of the problems of the sense, treatment technology, treatment cost or the lack of experience.3.1.3. the bottleneck of blowdown treatmentfrom the above description, significant initial cost was the bottleneck for developing blowdown treatment. the above encountered bottlenecks were mostly caused by technology problems. because of the cost concern, the industries continued to overpump groundwater or use more expensive portable water. nevertheless, iso 14000 regulates the aspects about environmental management systems, environmental performance evaluation and life cycle assessment, etc. we expect the concerned industries must pay more attention to the environmental issues. to meet the iso 14000s requirement, the industries in taiwan should increase their cycles of concentration to reduce blowdown or reuse the producing wastewater for cooling water. in addition, the water pollution induced from blowdown also becomes an environmental concern. from the above discussion, the encountered bottlenecks of cooling water reuse are related to technology, economics and environment. these bottlenecks can be overcome if the government authorities and policies support the industries.4. conclusioncooling water usage occupies more than one half of the industrial water supply.if its volume can be reduced, the industrial water supply can be markedly depressed. in addition, this may also decrease the impact of blowdown, and decrease the land sinking that induced from groundwater overpumping. from the above perspectives, the reclamation of cooling water is an inevitable trend. to reuse and recover the cooling water is feasible when using proper technology. 冷却水的回收和再利用的潜力 摘要 冷却水是工业回用水重要组成部分，无论是从需求的优先级或供应量的看。为了节约用水，供应系统的负载，可以降低冷却水可以回收再利用。出于这个原因，探索对冷却水系统运行状况近期已成为重要的一研究。这项研究最初集中在当前的应用和冷却炼油厂，化工，钢铁厂，食品工业，电子工程，水，纺织厂重用趋势和发电站。据统计分析，饮用水和地下水是化妆水冷却系统的主要来源。多重化学物质治疗方法和化妆越来越接受了冷却水回收。另一方面，侧流处理和回用不排污很流行。对排污回收率仅为26.8，较高的成本其实是压低复苏的意愿一个主要原因。一些有代表性的植物已被选定为研究对象。然而，大多数只冷却水系统经营的运营商的经验都是根据实地调查。在每一种情况下，用水质指标来评估冷却水系统运行现状。在有任何情况的下，工厂都操作在适当的浓度周期。本文还介绍了冷却节水技术的瓶颈。这些瓶颈包括增加浓度循环，废水再利用，排污处理。这个文件还表明，冷却水回收和再利用具有很大的潜力，在目前来说现有的技术是可行的，但行业仍不愿因为初始成本升级最后，技术，经济，环境和相关的一些方法政策建议是为行业和政府部门参考。关键词：冷却水的回收与再利用;化妆;排污1. 简介 因为经济的高度增长，工业迅速发展和生活水准的提升, 水资源的需求明显增加。水源是难以发展的经济，由于土地下沉，地下水污染和新水库施工难。因此，如何回收和再利用的水是一种有效的办法来解决这个问题。其中行业的废水，冷却水是最宝贵的，因为它的恢复具有较大的体积和较少污染。另一方面，一些行业重复使用适当的治疗过程中的冷却废水或生活污水。虽然多种化学品用量的方法是一项成熟的技术增加回收量，必须评估潜在的重用和冷却水时，提高冷却水回用执行恢复进一步。这项研究有兴趣与感知冷却填海和回收和再利用的可行性水质，处理技术有关的事项。2.冷却水系统的特点和运作上的问题冷却水系统为一次通过，分为开放式循环和封闭循环系统。冷却水系统的操作与问题相结合，具有耐腐蚀，规模，污染和煤泥。腐蚀是由电化学反应诱导和诱导金属的重量损失，形成规模下金属盐类饱和，例如钙，镁，并在金属表面形成沉积物。结垢是造成腐蚀的产品或悬浮物是在金属表面附着。煤泥是由于微生物的生长也结合，结垢和腐蚀等的运作问题通常描述为与上述有关 有特点的冷却水系统。因此，重复使用冷却水，水的质量需要仔细考虑时。如果冷却水系统是在中性ph值，温度较低，较高的速度，较低的溶解盐类和营养物浓度的特点、操作、经营困难的情况可以减少。尤其是氮引起的问题。2.1 不同位置氨氮随时间变化关系 图.2 不同位置氨氮随时间变化曲线 从图中曲线变化的总趋可以看出距离污染源越近的取样点，污染物浓度值一般较大，靠近砂箱底部且远离污染源的取样点氨氮浓度变化最晚，反映最不