青岛电厂温排水对胶州湾海域影响评价

本文叙述了青岛电厂温排水对海域的环境影响,分析了温排水对胶州湾水质、沉积物、生物群落的影响,给出了影响范围和影响程度,研究结果为海洋环境保护提供了一定依据。     

青岛滨海电厂温排水对海洋生态环境影响研究现状

随着滨海电厂的迅速发展,电厂温排水排放对邻近海域的生态环境影响越来越受到人们的关注。文章概括了青岛电厂温排水数值模拟现状、温排水排放对海洋生态环境影响方面的一些研究成果,并提出了存在的问题和今后应关注的研究方向。     

浅谈我国滨海电厂温排水对海洋环境的影响状况

我国经济的发展对能源电力需求越来越大,滨海火/核电厂的大量建设在一定程度上缓解了紧张局面,但电厂温排水的排放对海洋环境和水产养殖等造成了影响。文章总结了我国电厂温排水(冷却水)及其对海洋环境等的影响状况,并对温排水管理和技术研究工作提出了几点看法。     

珠海电厂温排水分布特征及排水工程降温效果研究

根据2009-07和2010-01三次调查的数据,分析了珠海电厂温排水分布特征、季节变化;同时,利用调查资料分析排水明渠和跌入式阶梯的降温效果。结果显示,以排水口为中心,电厂温排水向外海扩散的距离越远,水温越低;最高温升4℃的影响面积小潮期大于大潮期,冬季大于夏季。电厂排水方式采用排水明渠有一定的降温效果,但效果不太明显,而温排水经跌入式阶梯跌落入海的降温效果较为突出,平均降温约3．7℃。     

滨海电厂温排水对生态环境影响研究进展

文章综述了滨海电厂温排水温升、余氯及卷载效应对附近海域生态系统中的浮游生物、底栖生物、鱼类等生物因子影响的研究进展,并阐述了滨海温排水对生态环境影响出现的新问题及今后研究趋势。     

海上浮式核电站温排水对海洋生态环境的影响

开发海上浮式核电站,可以有效地解决海洋工业的用能需求,符合国家能源发展战略。海上核电冷却循环系统产生的温排水会对海洋环境本体及其生态系统产生一定的负面影响,是环评工作关注的重点。论述了海上核电站温排水的特点,分析了其对受纳海域水文条件、海水水质、生态环境、生物群落组成与结构等方面产生的影响,提出了温排水的热污染控制对策。     

电厂温排水中余氯浓度预测

利用有限元分步杂交方法,对胶州湾海域潮流场进行了数值模拟。考虑余氯在水体中的化学反应,利用前人大量实验成果选取余氯衰减系数,建立胶州湾余氯的二维输运-扩散模型,并将此模型应用于青岛市黄岛发电厂三期温排水工程,预测了温排水中余氯的浓度分布及影响范围,为电厂冷却水排放口邻近水域的生态环境保护提供依据。     

萧山电厂温排水二维热污染数值模型

本文用二维水流方程和平面热扩散方程模拟电厂温排水在浦阳江中的扩散情况。在数值计算中,对二维水流方程采用显式迎流有限元方法,对平面热扩散方程采用显式直接差分法,并对这两种方法进行了耦合计算。比较全面地分析了电厂向浦阳江排水和取水后,浦阳江水温的分布特性,为选择电厂取排水的工程方式提供了判断依据。     

田湾海域温排水分布及变化规律分析

选取田湾核电站附近海域,采用定点连续、多点同步的水温分层现场观测方式,辅以连续高分辨率的气象、水位和海流等观测,分析研究了田湾核电温排水的分布及变化规律,绘制出逐时的1℃温升曲线,从而经计算得到与之相对应的温升在1℃以上的海域面积,并据此讨论了影响温排水的主要因子。结果表明,在现场观测期间,温排水面积变化趋势与潮汐潮流直接相关。在落急时刻,温排水面积达到最大值,为32.33km2。在涨憩时刻,温排水面积最小,仅为7.93km2。     

滨海电厂温排水用海管理范围界定初步研究

目前我国电厂温排水用海面积大、占用岸线长、形状不规则等问题已经造成海域资源的严重浪费,同时增加海域使用管理的难度。文章基于对我国18个滨海电厂温排水排放特性的调查研究,分析18个案例中的温排水用海确权情况,通过单位兆瓦发电量对温排水的实际用海面积和申请用海面积进行量化取值;针对案例分析结果,结合温排水降温效果,从方便温排水用海管理角度提出建议。     

Statistical analyses of the effects of a coastal power plant cooling system on underwater irradiance

The authors estimated the effects of a cooling water discharge from a coastal power plant on underwater light levels using 6 years of integrated hourly irradiance measurements which were taken at the sea bottom in water depths of 10–14m. They applied a before-after-control-impact design (BAC1) to the irradiance recordings. The basic BAC1 design estimates the power plant effect as the difference between the means of impact-control differences observed in separate periods after and before the power plant began operation. This design subtracts out constant spatial differences and uniform temporal changes, leaving only the time-by-location interaction which is the power plant effect. They modified the basic BACI analysis in several ways to deal with high natural variability, serial correlation in the data, and the effects of current direction. The daily irradiance data were divided into two sets of days in which the impact stations were downcurrent or upcurrent from the power plant discharge. For downcurrent days, the authors found significant (p < 0·0.016) reductions in irradiance ranging from 20 to 28% at three impact stations. For the upcurrent days, they found insignificant increases of about 14%.     

某滨海核电厂低放射性废水的海洋环境影响预评价

以某滨海核电厂为例,分析确定58 Co、60Co、90Sr、134 Cs、137 Cs和110m Ag等放射性核素为该核电厂低放射性废水中的主要海洋环境影响评价因子.根据国际原子能机构推荐的评估模式预测了上述放射性核素排海后对电厂排放口海域环境(海水水质和沉积物质量)的影响,预测结果表明该核电厂低放射性废水正常排放后,排放口附近海域海水中的58 Co、60Co、134Cs、1 10m Ag比活度低于放射性核素比活度背景值检测限2～3个数量级;90Sr低于背景值4个数量级;137Cs略高于背景值,对周围海水环境未造成放射性污染.但58 Co、60Co、134Cs、137Cs、110m Ag在排放口近岸海域沉积物中的沉积量分别比背景值检测限高2～5个数量级,其中60Co和110m Ag沉积量最大;90Sr沉积量低于放射性背景值2个数量级.最后提出可以从生物辐射评价和核素的迁移转化规律、联合效应(综合考虑温排水、低放射性废水和余氯)和选取合适的指示生物3个方面进行跟进研究的建议,以便更完善和全面地评价核电厂低放射性废水对排放口附近海域环境的影响.     

Chlorination by-products in chlorinated cooling water of some European coastal power stations

Chlorination by-products (CBPs) are formed as a result of the cnlorination of power station cooling water for anti-fouling purposes. Their production was studied at 10 coastal power stations in the UK, France and The Netherlands. Three categories of CBPs were determined: trihalomethanes; haloacetonitriles; and halophenols. Bromoform was the CBP most abundantly present in the effluents of all 10 power stations. At a mean chlorine dosage of 0.5–1.5 mg/litre (as Cl₂) the mean bromoform concentration was 16.32 ± 2.10 μg/litre. The CBP found in second highest concentrations was dibromoacetonitrile (DBAN) with mean concentrations of 1.48 ± 0.56 μg/litre. Other CBPs detected were dibromochloromethane, bromodichloromethane and 2,4,6-trichlorophenol; concentrations of these three compounds were very low (< 1 μg/litre). At those sites at which bromoform was measured in the dispersing effluent plume it was found to behave as a conservative parameter (Significant direct correlation with plume ΔT).     

浙江苍南电厂冷却水温排放的数值模拟

电厂排放的冷却水水量大且热量高,其排放的热水将引起周围水域水温的升高,导致不同程度的热污染.针对浙江苍南电厂附近海域水流和污染物的对流扩散特点,采用MIKE21软件对电厂温排水进行数值模拟,分析不同潮型、不同流量及不同季节下的最大温升包络面积和取水口的温升变化.研究结果表明,电厂冷却水温排放的最大温升包络面积范围与流速和水深的关系密切.从本工程的情况来看,在高温升(4 ℃)区以保证率为97%的低水位潮型下的最大温升包络面积为最大,达0.69 km2,大潮、中潮和小潮相应的面积分别为0.63、0.66和0.48 km2;在低温升(0.5 ℃)区以小潮相应的面积为最大,达14.96 km2,中潮、大潮和保证率为97%的低水位潮型相应的面积分别为13.48、10.30和6.90 km2.温升包络面积与电厂冷却水的排放量不为线性关系.冬季电厂冷却水排放的温升包络面积大于夏季,冬季4 ℃温升包络面积是夏季的3倍,其它各级温升包络面积为夏季的1.1～1.4倍.由于取排水口被挡沙防浪堤隔开,故取水口区域的温升较小.研究成果可为电厂的建设提供依据.     

滨海电厂钢筋混凝土腐蚀防护应用

某滨海电厂钢筋混凝土结构在海洋大气环境中腐蚀较重,通过分析已破坏的混凝土,确定腐蚀原因主要是二氧化碳腐蚀和氯离子腐蚀,采用TPEI——乳液砂浆和喷射混凝土两种方案,对钢筋混凝土结构进行修复,确保电厂设施正常安全运行。     

Transport of waste heat from a nuclear power plant into coastal water

A numerical and experimental modeling is presented for studying the transport of waste heat from a nuclear power plant into coastal water by using a full-field physical model with scale distortion, a local physical model with normal scale and a depth-averaged k− turbulence model with a modified second-order upwind scheme. Field investigations are also used to provide the calibration and validation of the modeling. A case study simulating the turbulent tidal flow and waste heat transport in the coastal water near Daya Bay Nuclear Power Plant in Southern China was conducted. The experimental result of the case study shows that the water temperature in coastal water was a little oversimulated near the surface and was a little undersimulated near the bottom of heated-water layer by the full-field physical model. The numerical study shows that the depth-averaged k− turbulence model presented a satisfied prediction of turbulent tidal flow and far-field temperature distribution in coastal water, although the near-field stratification due to the heated water effluent was not accounted for. The result of the effect of scale distortion on physical model shows that a full-field physical model with a scale distortion of 10 produced a satisfied result of temperature distribution in the present case study.     

滨海火电厂海水烟气脱硫对海洋环境影响的初步探讨

以华能威海电厂2×125MW工程海水脱硫项目为例对滨海火电厂海水烟气脱硫方法的条件、原理、工艺流程以及脱硫废海水排海后对水质环境的影响进行分析。结果表明,滨海火电厂利用海水对烟气脱硫取用条件十分方便,而且达到烟气脱硫、节能减排保护海洋环境的目的。     

Formation of thermohaline front by cooling of the sea surface and inflow of the fresh water

A numerical study of characteristics of the front formed by cooling of the sea surface and inflow of the fresh water is made within a vertical two-dimensional plane without the rotation of the earth. The convective adjustment technique is employed to parameterize the small scale convective overturning process.A sharply edged shelf causing the marked difference of the heat capacity of the water columns between over the shelf (50 m depth) and in the deeper region (150 m depth), is responsible for the formation of a thermal front over the shelf edge and two cell circulations of the same sense with each other adjoining at the frontal region.Inflow of the fresh water at the upper region of the coast (which is equivalently replaced by the outflow of the salt from the same region) adds a circulation of the opposite sense to the above ones, which transports the water of low salinity and low temperature offshore and forms a sharp front both of temperature and salinity with the offshore water of high salinity and high temperature. This thermohaline front or Oceanic front has a remarkable character that the horizontal density gradient is minimal at the front due to the counteracting contributions of temperature and salinity to density. Response of this front to the sudden ceases of the surface cooling and the fresh water supply, is also studied in order to understand its transient behaviors.