Moselle River电厂冷却水回路 斑马纹贻贝 控制—— 五种处理方法的试验.doc

美思国际 法国创新 Serving Industrial with TechnologyMexel4321MEXEL 432 ®法国Moselle发电厂冷却水回路 斑纹贻贝控制五种处理方法的比较“ TESTING OF FIVE METHODS FOR THE CONTROL OF ZEBRA MUSSELS IN COOLING CIRCUITS OF POWER PLANTS LOCATED ON THE MOSELLE RIVER ”<法国国家电力(EDF) 报告>不论是以(技术可行性)、(对抗贻贝的效果)或是(环保观点)和(处理成本)来说，试验结果显示使用Mexel.432是达到试验主旨所寻求的最佳处理方案。 本文译自EDF(法国电力公司) Report ”Testing of five methods for the control of Zebra (including MEXEL 432) - Ref DEF-DER-1993” (completed on Dec., 1993)目 录 试验目标 (Objectives) 方法 (Methods) 结果 (Results) 各种方法的比较 (Comparison of methods) 简介 (Introduction) Cattenom核能发电厂 (the Cattenom nuclear power plant) 机械式清洗 (Mechanical cleaning) Moselle河水的水质 (Water quality in the Moselle River) Moselle河Dreissena polymorpha生物数据 (Dreissena polymorpha in the Moselle) 热处理 (Thermal treatment) 瞬间氯化 (Shock chlorination) 二氧化氯 (Chlorine dioxide) 氯化钾 (Potassium chloride) 有机产品的测试 (Testing of an organic product) 结论与评论 (Conclusion and prospects) 参考资料 (References)法国Moselle River电厂冷却水回路 斑马纹贻贝 控制 <五种处理方法的试验> TESTING OF FIVE METHODS FOR THE CONTROL OF ZEBRA MUSSELS IN COOLING CIRCUITS OF POWER PLANTS LOCATED ON THE MOSELLE RIVER试验目标 (Objectives)位于Moselle River河谷的热电厂进水回路内长满了斑马纹贻贝，每年夏天将其幼虫产在河盆和渠道的壁面上。研究的主旨是要寻求可替代或可互补方案，以期得以清除回路中的斑马纹贻贝，依据过去已发展的一些防止斑马纹贻贝的处理方案(EDF/DER report HE/31-90.34)，作为现场评估选定处理方法的试验指导。Zebra mussels are building up in the raw water circuits of the thermal power plants located in the Moselle river valley. Their larvae settle in summer of every year on all the walls of the basins and galleries. The aim of this study is to seek alternative or complementary methods to annual cleaning of the circuits in order to eliminate zebra mussels. Following a bibliographical review of methods applicable to the prevention of zebra mussels ( EDF/DER report HE/31-90.34 ), an experimental study was conducted on site to assess the selected treatments.方法 (Methods)试验是在Cattenom核能发电厂进行，针对Moselle River采集的斑马纹贻贝。为了测试二氧化氯和有机产品MEXEL 432，一套试验设备是采用持续给水，水源来自电厂Moselle River河水的进流处。Tests were carried out at the Cattenom Nuclear Power Generation Center on zebra mussels samples collected in the Moselle River. To test chlorine dioxide and the organic compound, an experimental device was continuously fed with Moselle river water taken from the power plant water intake structure.结果 (Results)热处理：因为夏天的热度状况(适应温度在20-25)，37/20分钟或40/10分钟的瞬间热处理对于消除斑马纹贻贝是有效的。Thermal treatment. For summer thermal conditions ( acclimatization temperature in the of 20-25 range, ) a shock on the order of 37 for 20 minutes or 40 for 10 minutes is effective in eliminating the zebra mussels.瞬间氯化：使用高剂量氯化并且残余氯浓度为100-200 mg/l时，做2个24小时的添加处理可杀死斑马纹贻贝。Shock chlorination. It is possible to kill the zebra mussels with high-dosage chlorination and free-chlorine concentrations in the range of 100 to 200 ppm by a two 24-hour injections.二氧化氯：残余量0.2 mg/l持续8天的处理是有效的，较低浓度的长期添加也可达到效果。Chlorine dioxide. A continuous injection of 8 days with a residual of 0.2 ppm is effective, but smaller concentrations are also probably effective on a long term basis.氯化钾：斑纹贻贝对于钾非常敏感，可是需要非常高浓度的氯化钾，约需浓度600mg/l并做2天的添加处理。Potassium chloride. Zebra mussels are especially sensitive to potassium, though very high concentrations of potassium chloride are required: about 600 ppm for a two-day treatment.有机产品 MEXEL 432：M.432不含毒性有机物或矿物质，一旦混合于水中，会形成分子膜来对抗生物附着，直接作用在贻贝鳃，使用M.432的处理约需20小时7 mg/l (残余量3.5mg/l)的添加即可见效。An organic product: Mexel 432. This compound contains no toxic organic or mineral substances. Once mixed in the water, it forms a film which is responsible for its anti-fouling properties. probably by direct action on the gills of the mussels. Treatment with Mexel 432 is effective with injection of 7 ppm ( residuel 3.5 ppm ) for about 20 hours.各种方法的比较 (Comparsion of methods)热处理：不会产生化学排放物质。然而，以目前的冷却水系统而言，若没有特殊设计装置，此种处理方法，实际上应用起来非常困难。Thermal treatment does not generate chemical discharges. However, it is very difficult to implement in existing cooling water systems not especially designed for this purpose.二氧化氯： 由于处理Moselle River河水的高需求量，二氧化氯处理的成本非常昂贵；此外，二氧化氯处理会产生化学副产品；现场二氧化氯的生产是非常危险的，必须受到严格安全规则的规范。Chlorine dioxide is counter-indicated because of the cost due to the high demand in the Moselle water; in addition, it produces chemical releases of by-products. On site production of chlorine dioxide is also dangerous and implies compliance with strict safety rules.瞬间氯化 和 氯化钾：关于瞬间氯化或氯化钾的处理，只能使用在处理回路中最敏感区域的小量非-更新水，而且氯化也会产生有机卤素化合物。As regards shock chlorination or potassium chloride, the only solution is the treatment of small volumes of non-renewed water in the most sensitive sections of the circuit. Chlorination also produces organohalogenated compounds.有机产品 MEXEL 432：在施用技术和成本观点上，显示M.432的处理最理想。另外还要考虑的是环境影响：必须确认放流水中没有残余毒性。以下会更详细介绍M.432生物分解性和长期影响。Mexel 432 figures in best position in terms of technical feasibility and cost, but the environmental acceptability is not certain: it would be necessary to confirm that there is no residual toxicity in the discharged waters. More information is required on the degradation and long-term effects of this compound.简介 (Introduction)法国EDF.电力在Moselle、Rhone和Seine河谷的所有发电厂，在进水入口处和冷却水系统的多处不同区域，遭遇斑纹贻贝问题已有数十年的历史。Zebra mussels have for decades been found in the water intake structures and in different parts of the cooling systems on all of the EDF-operated power plants in the Moselle, Rhone and Seine river valleys.在八十年代初期，EDF.研发部门进行了多项研究：法国各大河川Dreissena polymorpha的生物习性(1)、使用氯及二氧化氯处理的试验(2)(3)，至今还没有特定的方法可采用来防止贻贝的生成。While several studies were undertaken by the EDF Research and Development Division at the beginning of the Eighties, on the biology of Dreissena polymorpha in large French rivers (1) and testing of chlorine or chlorine dioxide treatments (2) (3), no specific measures have yet been taken to prevent development of the mussels.一般而言，大型生物附着问题，可使用机械式清洗冷却系统。以EDF.的经验来说，河水的生物附着(bio-fouling)对于冷却系统的威胁较轻微，海水电厂冷凝器的藤壶(barnacles)和蓝贻贝(blue mussels)附着污塞问题比较严重。针对附着在冷却水塔填料(packing)上的periphyton(底栖性藻类)和algae(藻类)的消除，通常很少使用瞬间氯化处理，然而沿海电厂系统的防护措施则是采用持续低剂量氯化处理。In general, cleaning the cooling system by mechanical means solves the problem in cases of major infestation. In the experience of EDF, bio-fouling of rivers has been perceived as a lesser threat to cooling systems than that represented by barnacles and blue mhssels blocking condensers on marine plant sites. Shock chlorination is used very infrequently to eliminate periphyton and algae on the packing in cooling towers, whereas coastal power plant systems are protected by continuous low-dosage chlorination (4).1989年在EDF.Cattenom核能电厂，核能和非核能辅助冷却系统的热交换器，必须非常频繁的清洗，约400m3的斑纹贻贝和泥浆从给水管路中清出。为了解决交换器的堵塞危险，决定使用下述2种方法： 每年使用机械式清洗，来降低管壁上的贻贝数量 逐渐设置碎片过滤器(debris filter)，以防止贻贝和碎壳随着水流进到热交换器In 1989 at the EDF Cattenom plant, the heat exchangers on the nuclear and conventional auxiliary cooling systems had to be washed out very frequently, and some 400 m3 of zebra mussels and mud were removed from the pipes supplying the systems. To eliminate the risk of total clogging of the exchangers, it was decided to adopt two measures:- mechanical cleaning of the system every year, to reduce the quantity of mussels on the walls.- gradual installation of a debris filter, to protect the exchangers from mussels or pieces of shell being drawn into the pipes.1990年初，决定进行另一项计划来寻求更理想的处理方法，以取代每年使用机械清洗来清除斑纹贻贝的作业。Beginning in 1990, a program was undertaken to seek alternative or complementary methods to annual cleaning of the systems in order to eliminate zebra mussels.计划分为三个阶段：1. 依据过去已发展的处理方案，找出可应用于防止斑纹贻贝者2. 抗生物附着涂料和涂布的测试3. 选出5种对抗生物附着处理来进行试验：Ø 热处理Ø 瞬间氯化Ø 二氧化氯Ø 氯化钾Ø 有机产品MEXEL 432The program was threefold:1. a bibliographical review of methods applicable to the prevention of zebra mussels;2. testing of anti-fouling paints and coatings;3. testing of five anti-fouling treatments selected following the bibliographical review:- thermal treatment - shock chlorination - chlorine dioxide - potassium chloride - an organic compound (Mexel 432)测试是1991、1992年在Cattenom电厂进行，以下述4个标准做评估：对抗斑纹贻贝的有效性、无毒性、操作简单及成本效益。Tests were carried out at Cattenom in 1991 and 1992 with a view to assessing the selected treatments in terms of four criteria : effectiveness against the zebra mussel, absence of toxic releases, simplicity of implementation and cost.Cattenom核电厂 (the Cattenom nuclear power plant)EDF操作的Cattenom电厂具有4座1300-MW PWR机组，位于法国Moselle river河谷，每一机组配备一自然通风冷却水塔，每一机组的进流水以2.2 m3/s速率抽取Moselle river河水，抽取的进流水最先使用于冷却非核能和核能辅助系统，再作为主冷却系统的补充水。正常操作状况下，排放水流入一个大型的人造贮水池Mirgenbach贮水池在池中停留约10天后，再排放到Moselle河下流。水流在冷却水塔产生蒸发，每一机组回流到河中的水量是1.35 m3/s。The EDF-operated Cattenom nuclear power plant consists in four 1300-MW PWR units and is located in the French part of the Moselle River valley. Each unit is equipped with a natural-draft cooling tower. Water is pumped from the Moselle at a rate of 2.2 m3 /s for each unit. This water first cools the systems in the conventional and nuclear auxiliaries, then serves as makeup for the main cooling system. Under normal operating conditions, the blowdown waters are discharged into a large artificial reservoir-Mirgenbach reservoir-in which residence time is approximately ten days, before being released into the Moselle River downstream. Given evaporation in the cooling towers, the flow restored to the river is approximately 1.35 m 3/s per unit.机械式清洗 (Mechanical cleaning)目前，系统中的4个机组都是以潜水夫使用机械式清洗，这项操作每年约4个月(从11月到隔年2月)，在这种水底式的清洗作业中，需尽可能的降低循环水量，因辅助泵可能随时操作，对于潜水夫必须有特别的防护措施。刮除壁面的贻贝及管路中所有的壳片和底层泥浆，再使用吸引泵浦抽引至储存槽储放，以备相关测试使用。At the present time, the systems of all four units are mechanically cleaned by divers. The operation takes about four months per year (from November to February). During this underwater cleaning, water circulation is reduced as much as possible, but since auxiliary pumps can run at any time, special protection is required for the divers. The mussels are scraped off the walls and all shells and mud on the bottom of the pipes are removed by a suction pump and stored in a retention basin, for the purposes of measurement.Moselle河水的水质 (Water quality in the Moselle River)这段区域的Moselle河水质非常恶劣，主要是因为工业和民生污染，氯化物的工业放流污染使得溶解固体物质达到非常高的浓度。在夏天，特别是在过去几年遭受严重的干旱，低水流导致氨(0.21.0ppm)、亚硝酸盐(0.31.0ppm)、正磷酸盐(0.52.0ppm)的增加，这种营养盐丰富的水质造成浮游植物泛滥(叶绿素a：10-20g/l，58月)；在春天和夏天，发现由于过多浮游植物导致产生了悬浮物质(10-85ppm)。此地区气候特征，春天、夏天的水温超过20，多半为23-26。The quality of the water in this stretch of the Moselle is poor, primarily because of industrial and domestic pollution. Dissolved solids reach very high levels downstream of industrial discharges of chlorides. During the summer, and especially in the past few years marked by severe droughts, low flow rates have resulted in increased ammonia ( 0.2 to 1.0 ppm ), nitrites ( 0.3 to 1.0 ppm ) and orthophosphates ( 0.5 to 2.0 ppm ). Phytoplankton is abundant in this nutrient-rich water ( chlorophyll a: 10 to 120 g/l from May to August ). In spring and summer, phytoplankton contributes significantly to the suspended matter found in the river ( 10 to 85 ppm ).The thermal regime is characterized in spring and summer by water temperatures above 20 ,with long periods of time in the 23 to 26 range.Moselle河Dreissena polymorpha生物学资料 (Biological data on Dreissena polymorpha in the Moselle)幼虫的沉积时期和幼贻贝生长速率的正确资料，可用来判断处理的最佳时机：添加时间和处理频率。Precise data on larval settlement periods and on growth rates of young mussels is needed to determine the timing best suited to treatment: injection periods and frequency.Metz大学de De'moecologie实验室J.C.Moreteau教授进行的Moselle河贻贝Dressena的生物研究，P.Testard教授也针对Oise河(Seine河支流)的Dressena作类似的研究(5)。1991和1992年49月在Moselle河水进流口和Cattenom电厂机组#1、#2冷却水系统监测到大量沉积的浮游贻贝幼虫。A biological study was carried out on the Dreissena population in the Moselle by the Laboratoire de Demoecologie of the University of Metz , under the direction of Professor J. C. Moreteau. A similar study was carried out by P. Testard on Dreissena in the Oise River, a tributary of the Seine ( 5 ). Abundance and settlement of planktonic mussel larvae were monitored between April and September of 1991 and 1992, in the water intake on the Moselle and the cooling systems in units 1 and 2 at Cattenom.1991年4月和1992年5月开始记录veligers，6月到8月间其密度起伏变化很大，在2年之中，共发现4次幼虫密集的高峰期：1991年：6月底(主要高峰期)和7月底1992年：6月中和7月中，具相似密度(180230 veligers/L)The first veligers were recorded in April (1991) or in May (1992) , though the density fluctuates from June to August. In both years, two abundance peaks were found for larval density:1991: end of June ( the major peak ) and end of July;1992: mid-June and mid-July, with similar densities (180 to 230 veligers per liter).幼虫沉积密度的变动非常大。在1992年，记录的沉积数量7月(6,00010,000个/m2)低于8月和9月中旬的数量(最大数量是8月初72,000个/m2)。Larval settlement is also subject to significant fluctuations. In 1992, settlement recorded in July (6,000 to 10,000 per m2) was lower than that found in August and mid-September (maximum of 72,000 per m2 at the beginning of August ).这些数量的变动，说明了一个或二个贻贝主沉积的形成。These major fluctuations explain the formation of one or two major cohorts of settled mussels.1992年69月记录管路中5组沉积幼贻贝壳长(0.51.0mm)的详细资料，第1沉积记录的资料是每星期平均成长avg. 1.3 mm/week，从6月中旬到9月中旬的3个月期间，其尺寸已达到1516mm。Detailed measurements of shell length for 5 cohorts of young mussels (0.5 to 1.0 mm) were made in the water pipes between June and September 1992. For the first cohort, mean growth of 1.3 mm per week was recorded. Over the three months between mid-June and mid-September, the first cohort reached a size of 15 to 16 mm.上述Moselle河贻贝生长记录(avg. 1.3 mm/week)高于Jantz and Neumann (6)记录的1989年310月Rhine河最大壳长生长记录：每星期成长max. 0.60.8 mm/week。The mussel growth recorded in the Moselle in 1992 is higher than the maximum shell length increment found by Jantz and Neumann (6) from March to October 1989 in the Rhine : 0.6 to 0.8 mm per week.热处理 (Thermal treatment)于1992年5月和8月进行测试，贻贝样品收集自Moselle河水，储放在测试桶，以温度20.0-20.4水温持续换水，贻贝在5月时适应温度是20，在8月时则是25。Tests were carried out in May and August 1992 on samples collected in the Moselle River and kept in test tanks, with continuous renewal of water at temperatures ranging from 20.0 to 24 . In May, the acclimatization temperature was 20, whereas in August it was 25.贻贝样品使用2种尺寸：710 mm和1216 mm。并使用33、37和40来做热处理。Two size classes were tested: 7-10 mm and 12-16 mm. The samples were subjected to thermal shocks at 33 and 40 .经过4小时和24小时后测量死亡率，观察到死亡率有显着的提高。结果显示2个尺寸间的些微差异：经过24小时后，以33热处理的(710 mm)小型贻贝其中10%仍继续存活了5小时，然而所有(1216 mm)贻贝则全都死亡。在适应温度2025对于处理结果不会有影响。Mortality was measured after 4 hours and 24 hours; within this time range, there is a significant increase in the mortality rate. Results showed a slight difference between the two size classes: after 24 hours, 10% of the smaller mussels had survived exposure to a 33 shock for five hours, while the entire 12-16 mm sample had died. In the range of 20 to 25 , t