在重水堆核电机组的多次大修中,海水厂用水系统(RAW SERVICE WATER SYSTEM)一直处于大修关键路径或次关键路径之上。本文通过对海水厂用水系统大修计划时间窗口的思考,特别是增加了设备冷却水(RECIRCULATION SYSTEM)检修备用系统后,探...在重水堆核电机组的多次大修中,海水厂用水系统(RAW SERVICE WATER SYSTEM)一直处于大修关键路径或次关键路径之上。本文通过对海水厂用水系统大修计划时间窗口的思考,特别是增加了设备冷却水(RECIRCULATION SYSTEM)检修备用系统后,探讨进一步优化海水厂用水系统大修时间窗口、工作逻辑和方法,以期达到缩短大修总工期的最终目的。展开更多
Skeletonema tropicum is regarded as a species with an affinity to warm waters and it has never been reported in seas where temperatures drop below 11℃ in winter. Previous studies in China reported that S. tropicum wa...Skeletonema tropicum is regarded as a species with an affinity to warm waters and it has never been reported in seas where temperatures drop below 11℃ in winter. Previous studies in China reported that S. tropicum was restricted to subtropical and warm temperate seas （East and South China Seas）, but the species was recently found during August cruises of 2009 and 2010 in Jiaozhou Bay, Yellow Sea, located several hundred kilometers to the north. Here, winter water temperatures often drop below 5℃. Identification of S. tropicum was confirmed under light and scanning electronic microscopes and maximum cell abundance in Jiaozhou Bay was estimated as 1.73× 10^4 celI/L. This record of S. tropicum in Jiaozhou Bay represents a significant northward expansion in the geographic range of the species. Ship ballast water was identified as a possible carrier of S. tropicum from southern places along Chinese coastline, and in addition, thermal pollution from local power stations and seawater desalination plants may provide suitable conditions for species over-wintering.展开更多
Reverse osmosis （RO） is proved to be the most reliable, cost effective, and energy efficient in producing fresh water compared to other desalination technologies. It is the fastest-growing desalination technology wi...Reverse osmosis （RO） is proved to be the most reliable, cost effective, and energy efficient in producing fresh water compared to other desalination technologies. It is the fastest-growing desalination technology with a greater number of installations around the world. The economic and technical performance of a medium-capacity RO desalination plant （2,000 m^3/day） proposed to be installed in Umm Qasr city south of Basra, Iraq is analyzed using DEEP-3.2 software created by the International Atomic Energy Agency （IAEA）. This port city is located on the Gulf shore and does not have any fresh water resources. The analysis shows that the cost of fresh water produced by this plant is US$0.986/m^3 with a good quality of fresh water （279 ppm）, which is a reasonable price for this remote area. The analysis also shows an increase in water production cost of about 12% at increased electricity price from 0.06 to 0.1 US$/kWh, 53% when the seawater salinity increased from 35,000 to 45,000 ppm, 2.5% when the seawater temperature decreased from 33 ℃ to 20 ℃, and 0.71% when the interest rate increased from 0% to 5%. Pumping fresh water from the Basra purification plant （located 175 km north of Umm Qasr） is 22.16 times the cost and 236.7% poorer quality than the fresh water produced by the RO plant.展开更多
In this paper, operation characteristic of condensate polishing system is studied during startup, based on generator blowdown limit, given limit ion concentration in condensate during condenser leakage. Further give c...In this paper, operation characteristic of condensate polishing system is studied during startup, based on generator blowdown limit, given limit ion concentration in condensate during condenser leakage. Further give conclusion about condensate polishing system configuration and operation requirement： full flow condensate polishing system （CPS） is necessary to the units cooled by sea water, and it is better that one or two series put in service during normal operation other than all of them in hot standby. While continuous condensate tube leakage is 256 L/h, the units cooled by fresh water will be shutdown immediately, for this level leakage, whichever condensate polishing system capacity is 50% （30%） or 100%, action level 2 will be preformed, so 50% （30%） is enough for fresh water cooled units.展开更多
Desalination processes have environmental impacts. The brine water discharge has an impact on marine ecosystem. This is mostly due to the highly saline brine that is discharged into the sea, which may be increased by ...Desalination processes have environmental impacts. The brine water discharge has an impact on marine ecosystem. This is mostly due to the highly saline brine that is discharged into the sea, which may be increased by temperature, contain residual chemicals from the pretreatment process, heavy metals from corrosion or intermittently used cleaning agents. The effluent from desalination plants is a multi-component waste, with multiple effects on water, sediment and marine organisms. Therefore, it affects the quality of the resource which it depends on. In this study, selected water quality parameters in the seawater and the presence of heavy metals of concern in the sediments and algae were monitored to investigate the impacts of the discharges by seawater desalination plants using reverse osmosis on the receiving marine environment. In light of the results obtained, the analyzed water has a physicochemical quality more or less adequate, moreover, chemical analyzes in seaweed and sediments show relatively low levels of heavy metals.展开更多
文摘在重水堆核电机组的多次大修中,海水厂用水系统(RAW SERVICE WATER SYSTEM)一直处于大修关键路径或次关键路径之上。本文通过对海水厂用水系统大修计划时间窗口的思考,特别是增加了设备冷却水(RECIRCULATION SYSTEM)检修备用系统后,探讨进一步优化海水厂用水系统大修时间窗口、工作逻辑和方法,以期达到缩短大修总工期的最终目的。
基金Supported by the National Natural Science Foundation of China (Nos.40976097, 41006040)the Strategic Priority Research Program of Chinese Academy of Sciences (No. XDA05130703)the Marine Special Scientific Fund for Non-profit Public Industry (No. 200805031)
文摘Skeletonema tropicum is regarded as a species with an affinity to warm waters and it has never been reported in seas where temperatures drop below 11℃ in winter. Previous studies in China reported that S. tropicum was restricted to subtropical and warm temperate seas （East and South China Seas）, but the species was recently found during August cruises of 2009 and 2010 in Jiaozhou Bay, Yellow Sea, located several hundred kilometers to the north. Here, winter water temperatures often drop below 5℃. Identification of S. tropicum was confirmed under light and scanning electronic microscopes and maximum cell abundance in Jiaozhou Bay was estimated as 1.73× 10^4 celI/L. This record of S. tropicum in Jiaozhou Bay represents a significant northward expansion in the geographic range of the species. Ship ballast water was identified as a possible carrier of S. tropicum from southern places along Chinese coastline, and in addition, thermal pollution from local power stations and seawater desalination plants may provide suitable conditions for species over-wintering.
文摘Reverse osmosis （RO） is proved to be the most reliable, cost effective, and energy efficient in producing fresh water compared to other desalination technologies. It is the fastest-growing desalination technology with a greater number of installations around the world. The economic and technical performance of a medium-capacity RO desalination plant （2,000 m^3/day） proposed to be installed in Umm Qasr city south of Basra, Iraq is analyzed using DEEP-3.2 software created by the International Atomic Energy Agency （IAEA）. This port city is located on the Gulf shore and does not have any fresh water resources. The analysis shows that the cost of fresh water produced by this plant is US$0.986/m^3 with a good quality of fresh water （279 ppm）, which is a reasonable price for this remote area. The analysis also shows an increase in water production cost of about 12% at increased electricity price from 0.06 to 0.1 US$/kWh, 53% when the seawater salinity increased from 35,000 to 45,000 ppm, 2.5% when the seawater temperature decreased from 33 ℃ to 20 ℃, and 0.71% when the interest rate increased from 0% to 5%. Pumping fresh water from the Basra purification plant （located 175 km north of Umm Qasr） is 22.16 times the cost and 236.7% poorer quality than the fresh water produced by the RO plant.
文摘In this paper, operation characteristic of condensate polishing system is studied during startup, based on generator blowdown limit, given limit ion concentration in condensate during condenser leakage. Further give conclusion about condensate polishing system configuration and operation requirement： full flow condensate polishing system （CPS） is necessary to the units cooled by sea water, and it is better that one or two series put in service during normal operation other than all of them in hot standby. While continuous condensate tube leakage is 256 L/h, the units cooled by fresh water will be shutdown immediately, for this level leakage, whichever condensate polishing system capacity is 50% （30%） or 100%, action level 2 will be preformed, so 50% （30%） is enough for fresh water cooled units.
文摘Desalination processes have environmental impacts. The brine water discharge has an impact on marine ecosystem. This is mostly due to the highly saline brine that is discharged into the sea, which may be increased by temperature, contain residual chemicals from the pretreatment process, heavy metals from corrosion or intermittently used cleaning agents. The effluent from desalination plants is a multi-component waste, with multiple effects on water, sediment and marine organisms. Therefore, it affects the quality of the resource which it depends on. In this study, selected water quality parameters in the seawater and the presence of heavy metals of concern in the sediments and algae were monitored to investigate the impacts of the discharges by seawater desalination plants using reverse osmosis on the receiving marine environment. In light of the results obtained, the analyzed water has a physicochemical quality more or less adequate, moreover, chemical analyzes in seaweed and sediments show relatively low levels of heavy metals.
