海水系统主要问题及处理-中英对照
Main Problems of Sea Water and Its Solutions
许卫东 Xu Weidong
（江苏核电有限公司222042）
摘要：本文简述了海水取水系统存在的主要问题及产生的原因，处理措施及建议处理方案，目的为了保障机组正常运行的海水冷却水供应，尤其是在机组夏季需要大量冷却水的情况下提供稳定的海水供应。
Abstract: The article describes the main problems existing in sea water intake system, its causes, treatment measures and solutions, for the propose of supplying cooling water of sea water to ensure normal operation of unit, especially providing stable seawater supply to unit in summer when the unit demands a large amount of cooling water.
关键词：除污机、旋转滤网、杂物、堵塞
Key words: Pollutant remover, rotation filter screen, sundries, block
1. 海水系统和设备概述 Seawater system and equipment description
1.1 海水系统介绍 Introduction of Seawater System
海水田湾核电站海水取水系统包括常规岛供水系统（PA系统）和核岛供水系统（PE系统），PA系统与PE系统在外海至厂外引水隧洞出水构筑物（01UPR）之前共用一条直径6米的厂外引水隧洞。PA系统的海水经暗沟、厂内引水隧洞直接到达海水循环泵入口，而PE系统的海水经前池缓冲、沉淀、净化后通过暗沟供给安全厂用水系统海水泵，海水比较干净，同时，PE系统用水量极小，不到总水量的5％，因此本文只针对PA系统。
Seawater intake system of seawater Tianwan nuclear power station consists of conventional island water supply system (PA system) and nuclear island water supply system (PE system). PA system and PE system share a outside-plant diversion tunnel with 6m diameter in the front of outlet structure of diversion tunnel from open sea to outside plant. The seawater of PA system is flown from blind ditch and inside-plant diversion tunnel to directly reach inlet of seawater circulation pump. However, PE system seawater is supplied to xxx pump of safe plant water consuming system through blind ditch after it is buffered in front pool, precipitated and purified. The xxx is clean. Meanwhile, the water consumption of PE system is little, less than 5% of total water amount, therefore, the article only aims at PA system.
工艺流程：PA系统的工艺流程为：引水明渠（01UPA）－厂外引水隧洞进水构筑物（01UPR）－厂外引水隧洞（01UPL）－厂外引水隧洞出水构筑物（01UPR）－厂内循环冷却水引水暗沟（UPM）－循环冷却水连接井（01UPD）－厂内循环冷却水引水隧洞（11UPN）－消波池（UPF）－除污格栅、旋转滤网－常规岛厂房冷却水用户（MAG、PGB、QKM）－虹吸井（UQF）－厂内循环冷却水排水暗沟（11UQN）－循环冷却水排水构筑物（01UQQ）－大海。
Process：Process of PA system：Intake open channel（01UPA）－Inlet structure of outside-plant intake tunnel （01UPR）－outside-plant intake tunnel （01UPL）－Outlet structure of outside-plant intake tunnel （01UPR）－Intake blind ditch of inside-plant circulation cooling water（UPM）－Junction well of circulation cooling water（01UPD）－Intake tunnel of inside-plant circulation cooling water(11UPN）－water absorption pool（UPF）－pollutant removing grille, rotation filter screen－Cooling water user of conventional island workshop（MAG、PGB、QKM）－虹吸井（UQF）－Outlet of blind ditch for inside-plant circulation cooling water（11UQN）－Outlet structure of circulation cooling water（01UQQ）－Sea.
1.2 主要设备 Main Equipment
取水明渠（拦污网）——粗格栅（15cm）——细格栅（5cm）——UQA厂房格栅和除污机（2cm）——旋转滤网。
Intake open channel（Dust barrier screen）——rough grille（15cm）——fine grille（5cm）——UQA workshop grille and pollutant remover（2cm）——rotation filter screen.
2. 海水系统主要问题及原因分析 Main Problems of Seawater System and Its Reason Analysis
2.1 海水水质差，容易造成堵塞 Water quality of seawater is poor so as to it is easy to cause blocking
高公岛附近的海水水质差，海水中有大量杂物，同时海生物在设备上大量生长对取水系统构成威胁。机组投入运行以来，共出现3次堵塞和取水不足造成机组降负荷。主要有：05年海生物在格栅和隧洞壁生长造成取水阻力增大，取水水量不足使机组降负荷。06年7月、07年7月大量麦秸秆涌入取水明渠，堵塞格栅，造成机组降负荷。
The water quality of seawater in Gaogong island is poor, with a large amount of sundries in it. Meanwhile, a lot of marine plants growing on the equipment threaten the intake system. After the unit is operated, it causes 3 blocks and insufficient intake to force load reduction. The details are followed: In 2005, the marine plants growing on the grille and tunnel wall resulted in increasing intake resistance and reducing the load of unit because of insufficient intake. In July 2006 and July 2007, a lot of wheat straws flowed into intake open channel to block the grille, which forced the unit to reduce the loads.
2.2 海水中杂物构成 Sundries compositions in seawater
2.2.1 每年11月~次年4月份，是近海的紫菜养殖时间。在此期间紫菜都有大量脱落的情况发生。分别是：
From Nov. of each year-April of next year, it is the season of culturing the laver in offshore. During the period, lots of lavers are dropped off. It is respectively followed:
海水流通不畅或种植过密，易产生病害，腐烂流失，病烂易发生在11～12月。
Flow of xxx is not smoothly or laver is cultured too dense so as to it is easy to cause disease, decay and loss. It is more often to cause disease and decay in Nov.-Dec.
冬季风浪持续时间较长，渔民来不及收割，较长的紫菜会被风浪打掉，时间在12月~2月。
The wind wave lasts for a long time in winter. Before the fish man harvests the laver, the long laver is broken by wind wave from Dec. to Feb.
春季气温升高时，紫菜生长加快，春末的紫菜经多次剪收后，已衰老质差不能食用，渔民大多将其丢弃在海里。时间在3月~4月。
The temperature is raised in spring so as to the laver is grown fast. However, after the laver at the end of spring is trimmed for many times, it is old with poor quality and not available for eating, therefore, the fish man discards it in the sea. The time is from March to April.
2.2.2 每年6~7月份的麦收季节，大量麦秸秆受风吹和雨水冲刷直接进入海中。导致堵塞取水口，造成将机组降负荷运行。
The wheat is harvested in June-July each year, so lots of wheat straws are blown by the wind and scoured by the rain and then directly flown into the sea, which results in blocking the intake and reducing the loads of the unit.
图1：取水明渠清理麦秸秆情况
Diagram 1: Cleaning the wheat straws in intake open channel
2.2.3 每年春末夏初天然海生植物、藻类大量繁殖。增加设备除污负担。
At the end of spring and at the beginning of summer each year, natural marine plant and alga are reproduced in large amounts, which increases the burden of equipment to remove the pollutants.
图2：格栅正面上海生植物情况
Diagram 2:Marine plant conditions on the front of grille
图3：格栅背面海生植物情况
Diagram 3: Marine plant conditions on the back of grille
2.2.4 海中天然生长小鱼、小虾在夏季大量繁殖，增加设备除污负担。下图为滤网停运10分钟后网片上的照片。
The small fishes and shrimps naturally grown in the sea are reproduced in large amounts in summer, which increases the burden of equipment to remove the pollutants. The following diagram describes the screen conditions after the filter screen is stopped for 10 minutes.
图4：旋转滤网上鱼虾情况
Diagram 4: Fishes and shrimps on the rotation filter screen
2.3 海水系统设备故障多 Various failures of seawater system equipments
2.3.1 格栅除污机效率低下、故障频繁（构成堵塞主要因素）。
Low efficiency of grille pollutant remover and frequent failures (it is the main reason of blocking).
高公岛取水构筑物上第一道和第二道拦污装置的所有格栅清污机、包括UQA厂房的2cm俄供格栅除污机在使用时，清理的杂物很少，对于紫菜、海生植物、鱼、虾等杂物不能有效清除。在大量麦秸秆堵塞时，能够清理出少部分，格栅除污机只能起到疏通作用，使大量麦秸秆进入下一级除污设备，而此时，已经发生了堵塞事件。对于UQA厂房的俄供2cm格栅除污机，除了上述去污效果差外，在正常运行过程中故障频繁，主要表现在以下几个方面：
When all grille pollutant removers (including 2cm grille pollutant remover supplied by Russian) at the first and second pollutant barrier devices of Gaogong island intake structure are used, it can clean few sundries. For laver, marine plants, fish and shrimps, it can’t clean them effectively. When lots of wheat straws block, only a few straws can be cleaned so as to the grille pollutant remover only functions as dredging and force lots of wheat straws to enter next stage pollutant removing equipment. At that time, the blocking is already formed. For 2cm yyy supplied by Russian in UQA workshop, in addition to the above poor pollutant removing effects, it fails frequently in normal operation, and its failures are followed:
耙斗容易发生卡轨：俄供除污机的耙斗部分借用拦污栅导槽，在水下格栅处采用变轨设计，具有一个转弯，当耙斗到达变轨处，容易发生卡涩现象。
Scraper bucket easily trap the rail: the scraper bucket of pollutant remover supplied by Russian shares the guidance channel of trash rack, and it adopts rail transfer design, with a turning. When the scraper bucker reaches the rail transfer point, it is easy to trap.
钢丝绳乱绳：俄供除污机的钢丝绳滚筒的螺旋槽采用浅槽设计，对钢丝绳的定位效果不好，且滚筒下多个被动轮没有对钢丝绳有效定位，增加了钢丝绳乱槽几率。
Steel rope is mixed: the spiral groove of steel rope roller in the pollutant remover supplied by Russian adopts the shallow groove so as to it can’t effectively position the steel rope, moreover, various passive wheel under roller can’t effectively position the steel rope, which increase the rate of mixing the steel rope.
电气限位容易失灵：俄供除污机采用复杂的传动机构，机械的复杂决定了电气的复杂，且限位装置采用多个不可靠的行程开关，增加了系统的不可靠性，任何环节出现问题，都导致除污机无法使用。
Electric positive stop easily fails: The pollutant remover supplied by Russian uses complicated driving mechanism. The complication of machine decides that of electric, furthermore, the positive stop device adopts various unreliable stroke switches, which increase the unreliability of system. So if any chain fails, the pollutant remover can’t be used.
耙斗清污效果不好：俄供除污机耙斗采用三根钢丝绳控制，其中两根钢丝绳负责提升耙斗，另外一根钢丝绳负责耙斗打开闭和，该结构除污机具有耙斗打开角度小，承载污物少的缺点。
Poor effects of scraper bucket to remove the pollutants: the scraper bucket of pollutant remover supplied by Russian uses 3 steel ropes to control among which two steel ropes are used to lift the scraper bucket and the rest one to open and close the scraper bucket. Such pollutant remover is characterized in small opening angle of scraper bucket and carrying little sewage.
由于除污机去污效果差，同时，运行过程中容易出现故障，尤其是在海水中出现麦秸杆情况时堵塞格栅，是造成机组降负荷运行主要原因。2007年7月14日凌晨因大量麦秸杆附着在UQA厂房格栅上造成巨大的水头损失，导致2#机组降功率运行。
The main reasons of reducing the loads of unit to operate are that poor pollutant removing effects of remover and frequent failures in the operation process as well as the wheat straws blocking the grille in xxx. At the early morning of July 14th 2007, lots of wheat straws are attached to UQA workshop grille to cause huge water head losses and to operate 2# unit at reduced power.
2.3.2 旋转滤网能力不足，故障频繁 Insufficient capability of rotation filter screen and frequent failures
由于高公岛取水海水中杂质较多，俄供旋转滤网不能满足田湾核电站使用要求。主要表现在以下几个方面：
Because of multiple sundries in intake xxx of Gaogong island, rotation filter screen supplied by Russian can’t meet the using requirements of Tianwan nuclear power plant. It is described as following:
旋转滤网驱动力不足：俄罗斯旋转滤网电机采用4KW，电机电流7.5A，过载保护电流12.5A，旋转滤网最大液位差500mm。而在田湾核电站实际运行中，在液位差没有达到500mm时，旋转滤网频繁出现过载而无法启动。
Driving force of rotation filter screen is insufficient: Russian rotation filter screen motor adopts 4kw, with 7.5A motor current, 12.5A overload protection current, 500mm maximum water level differences of rotation filter screen. However, in the actual operation of Tianwan nuclear power plant, when the water level difference doesn’t reach 500mm, the rotation filter screen overloads frequently so no starting is possible.
旋转滤网运行方式不能满足要求：俄罗斯旋转滤网维护手册1.3. 2.1条规定：旋转滤网每8小时运行15~30分钟。由于海水中杂物较多，根据统计，每天旋转滤网需要运行6~15小时，俄罗斯滤网维护手册规定的运行方式无法满足田湾现场要求。
Operation mode of zzz can’t meet the requirements: Article 1.3.2.1 in Russian zzz maintenance manual stipulates: zzz operates 15-30 minutes each 8 hours. For multiple sundries in the xxx, according to statistical, the zzz needs to work for 6-15 hours each day. The operation mode stipulated in Russian zzz maintenance manual can’t meet the requirements of Tianwan site.
零部件磨损严重：由于滤网实际运行时间远远大于滤网维护手册规定的时间要求，因此，需要滤网零部件磨损严重。主要原因是链条结构和材料选择不合理造成。见图5、图6中5mm厚的铜轴套和不锈钢轴套磨损情况。
Components worn seriously: Because the actual operation time of filter screen is far more than that stipulated in filter screen maintenance manual
侧密封不严，容易卡涩：俄罗斯旋转滤网侧密封板在轨道中运行的方式进行密封。这种方式不能有效阻止杂物进行滤网净水区，同时，很容易出现侧密封板变形导致旋转滤网卡涩故障。
网板之间密封不严和夹杂物无法去除：俄罗斯旋转滤网采用两块网板之间增加橡胶条的方式，对阻挡杂物进入净水区的效果不佳，同时杂物容易夹再橡胶条和网板之间，无法去除。橡胶条还需要定期更换，维护工作量大。
图5；铜轴套磨损情况 图6：不锈钢轴套磨损情况
2.4 海生物生长影响 Growth effects of marine plants
2.4.1取水口粗格栅、细格栅海生物生长严重。
由于高公岛取水口粗格栅位于加氯管道上游，不受加氯保护，海生物附着生长严重。细格栅紧邻加氯管道，而加氯管线线状布置，在面积很大的过水截面中扩散不均匀，无法有效防止海生物附着生长。
2.4.2 隧洞洞壁海生物生长严重。
由于田湾核电站从2003年隧洞通水后，机组处于安装调试阶段，取水量不稳定，加氯也不正常。导致大量海生物在隧洞附着，增加洞壁摩擦系数，导致供水不足。2005年底机组调试时出现循环水泵取水不足情况。
图7：洞壁生长海生物情况
2.4.3 设备上海生物生长情况。
目前，已经出现海生物在UQA厂房海水设备上生长的情况。
图8： 海生物在滚轮上生长情况
造成海生物生长主要原因为制氯站的制氯能力不足，以及机组调试期间加氯工作不正常等多方面因素。
海水系统主要问题及处理
许卫东
（江苏核电有限公司222042）
摘要：本文简述了海水取水系统存在的主要问题及产生的原因，处理措施及建议处理方案，目的为了保障机组正常运行的海水冷却水供应，尤其是在机组夏季需要大量冷却水的情况下提供稳定的海水供应。
关键词：除污机、旋转滤网、杂物、堵塞
3. 海水系统和设备概述
1.1 海水系统介绍
海水田湾核电站海水取水系统包括常规岛供水系统（PA系统）和核岛供水系统（PE系统），PA系统与PE系统在外海至厂外引水隧洞出水构筑物（01UPR）之前共用一条直径6米的厂外引水隧洞。PA系统的海水经暗沟、厂内引水隧洞直接到达海水循环泵入口，而PE系统的海水经前池缓冲、沉淀、净化后通过暗沟供给安全厂用水系统海水泵，海水比较干净，同时，PE系统用水量极小，不到总水量的5％，因此本文只针对PA系统。
工艺流程：PA系统的工艺流程为：引水明渠（01UPA）－厂外引水隧洞进水构筑物（01UPR）－厂外引水隧洞（01UPL）－厂外引水隧洞出水构筑物（01UPR）－厂内循环冷却水引水暗沟（UPM）－循环冷却水连接井（01UPD）－厂内循环冷却水引水隧洞（11UPN）－消波池（UPF）－除污格栅、旋转滤网－常规岛厂房冷却水用户（MAG、PGB、QKM）－虹吸井（UQF）－厂内循环冷却水排水暗沟（11UQN）－循环冷却水排水构筑物（01UQQ）－大海。
1.2 主要设备
取水明渠（拦污网）——粗格栅（15cm）——细格栅（5cm）——UQA厂房格栅和除污机（2cm）——旋转滤网。
4. 海水系统主要问题及原因分析
2.1 海水水质差，容易造成堵塞
高公岛附近的海水水质差，海水中有大量杂物，同时海生物在设备上大量生长对取水系统构成威胁。机组投入运行以来，共出现3次堵塞和取水不足造成机组降负荷。主要有：05年海生物在格栅和隧洞壁生长造成取水阻力增大，取水水量不足使机组降负荷。06年7月、07年7月大量麦秸秆涌入取水明渠，堵塞格栅，造成机组降负荷。
2.2 海水中杂物构成
2.2.1 每年11月~次年4月份，是近海的紫菜养殖时间。在此期间紫菜都有大量脱落的情况发生。分别是：
海水流通不畅或种植过密，易产生病害，腐烂流失，病烂易发生在11～12月。
冬季风浪持续时间较长，渔民来不及收割，较长的紫菜会被风浪打掉，时间在12月~2月。
春季气温升高时，紫菜生长加快，春末的紫菜经多次剪收后，已衰老质差不能食用，渔民大多将其丢弃在海里。时间在3月~4月。
2.2.5 每年6~7月份的麦收季节，大量麦秸秆受风吹和雨水冲刷直接进入海中。导致堵塞取水口，造成将机组降负荷运行。
图1：取水明渠清理麦秸秆情况
2.2.6 每年春末夏初天然海生植物、藻类大量繁殖。增加设备除污负担。
图2：格栅正面上海生植物情况
图3：格栅背面海生植物情况
2.2.4 海中天然生长小鱼、小虾在夏季大量繁殖，增加设备除污负担。下图为滤网停运10分钟后网片上的照片。
图4：旋转滤网上鱼虾情况
2.3 海水系统设备故障多
2.3.1 格栅除污机效率低下、故障频繁（构成堵塞主要因素）。
高公岛取水构筑物上第一道和第二道拦污装置的所有格栅清污机、包括UQA厂房的2cm俄供格栅除污机在使用时，清理的杂物很少，对于紫菜、海生植物、鱼、虾等杂物不能有效清除。在大量麦秸秆堵塞时，能够清理出少部分，格栅除污机只能起到疏通作用，使大量麦秸秆进入下一级除污设备，而此时，已经发生了堵塞事件。对于UQA厂房的俄供2cm格栅除污机，除了上述去污效果差外，在正常运行过程中故障频繁，主要表现在以下几个方面：
耙斗容易发生卡轨：俄供除污机的耙斗部分借用拦污栅导槽，在水下格栅处采用变轨设计，具有一个转弯，当耙斗到达变轨处，容易发生卡涩现象。
钢丝绳乱绳：俄供除污机的钢丝绳滚筒的螺旋槽采用浅槽设计，对钢丝绳的定位效果不好，且滚筒下多个被动轮没有对钢丝绳有效定位，增加了钢丝绳乱槽几率。
电气限位容易失灵：俄供除污机采用复杂的传动机构，机械的复杂决定了电气的复杂，且限位装置采用多个不可靠的行程开关，增加了系统的不可靠性，任何环节出现问题，都导致除污机无法使用。
耙斗清污效果不好：俄供除污机耙斗采用三根钢丝绳控制，其中两根钢丝绳负责提升耙斗，另外一根钢丝绳负责耙斗打开闭和，该结构除污机具有耙斗打开角度小，承载污物少的缺点。
由于除污机去污效果差，同时，运行过程中容易出现故障，尤其是在海水中出现麦秸杆情况时堵塞格栅，是造成机组降负荷运行主要原因。2007年7月14日凌晨因大量麦秸杆附着在UQA厂房格栅上造成巨大的水头损失，导致2#机组降功率运行。
2.3.2 旋转滤网能力不足，故障频繁
由于高公岛取水海水中杂质较多，俄供旋转滤网不能满足田湾核电站使用要求。主要表现在以下几个方面：
旋转滤网驱动力不足：俄罗斯旋转滤网电机采用4KW，电机电流7.5A，过载保护电流12.5A，旋转滤网最大液位差500mm。而在田湾核电站实际运行中，在液位差没有达到500mm时，旋转滤网频繁出现过载而无法启动。
旋转滤网运行方式不能满足要求：俄罗斯旋转滤网维护手册1.3. 2.1条规定：旋转滤网每8小时运行15~30分钟。由于海水中杂物较多，根据统计，每天旋转滤网需要运行6~15小时，俄罗斯滤网维护手册规定的运行方式无法满足田湾现场要求。
零部件磨损严重：由于滤网实际运行时间远远大于滤网维护手册规定的时间要求，因此，需要滤网零部件磨损严重。主要原因是链条结构和材料选择不合理造成。见图5、图6中5mm厚的铜轴套和不锈钢轴套磨损情况。
侧密封不严，容易卡涩：俄罗斯旋转滤网侧密封板在轨道中运行的方式进行密封。这种方式不能有效阻止杂物进行滤网净水区，同时，很容易出现侧密封板变形导致旋转滤网卡涩故障。
网板之间密封不严和夹杂物无法去除：俄罗斯旋转滤网采用两块网板之间增加橡胶条的方式，对阻挡杂物进入净水区的效果不佳，同时杂物容易夹再橡胶条和网板之间，无法去除。橡胶条还需要定期更换，维护工作量大。
图5；铜轴套磨损情况 图6：不锈钢轴套磨损情况
2.4 海生物生长影响
2.4.1取水口粗格栅、细格栅海生物生长严重。
由于高公岛取水口粗格栅位于加氯管道上游，不受加氯保护，海生物附着生长严重。细格栅紧邻加氯管道，而加氯管线线状布置，在面积很大的过水截面中扩散不均匀，无法有效防止海生物附着生长。
2.4.4 隧洞洞壁海生物生长严重。
由于田湾核电站从2003年隧洞通水后，机组处于安装调试阶段，取水量不稳定，加氯也不正常。导致大量海生物在隧洞附着，增加洞壁摩擦系数，导致供水不足。2005年底机组调试时出现循环水泵取水不足情况。
图7：洞壁生长海生物情况
2.4.5 设备上海生物生长情况。
目前，已经出现海生物在UQA厂房海水设备上生长的情况。
图8： 海生物在滚轮上生长情况
造成海生物生长主要原因为制氯站的制氯能力不足，以及机组调试期间加氯工作不正常等多方面因素。
3. 海水系统处理措施及建议方案
3. Treatment measure and proposal scheme of seawater system
3.1 针对海水水质差制定的措施和方案
3.1 Measure and scheme against the bad water quality of sea water
3.1.1 海水杂物较多，采取纵深防御措施，在取水明渠设置3道拦污网
3.1.1 As sundries are more common in sea water, it is applicable to take the depth defense measure and arrange 3 dust barrier screens in the intake open channel.
第一道拦污网的网孔80×80mm，设置在取水明渠头部。拦污网采用固定式，通过水泥桩固定，在每年6~7月安装使用，主要目的拦截麦秸杆功能。
Mesh of the first dust barrier screen shall be 80×80mm, which is arranged at the front part of intake open channel. The water screen adopts the regular type and shall be fixed with cement stake. It shall be installed and put in operation in June - July every year. The main purpose the water screen is to block the wheat straw.
第二道拦污网的网孔50×50mm，设置在取水明渠中部。拦污网采用浮漂，两端用缆绳在两端的桩上。
The second dust barrier screen shall be 50×50mm of the dirty network, which is arranged in the middle part of intake open channel. The water screen adopts floating type. The both ends of water screen shall be fixed on the stake.
第三道拦污网的网孔25×25mm，设置在取水明渠中后部，固定方式于第二道网方式相同。
The third dust barrier screen shall be 25×25mm of the dirty network, which is arranged in the end part of intake open channel. The fixing method is the same with the second water screen.
3.1.2 制定详细的海工系统应急预案
3.1.2 Establish the detailed emergency preplan of ocean engineering system
当海工系统的取水明渠出现大量杂物，如：麦秸杆、紫菜等，造成高公岛的拦污网、粗格栅、细格栅堵塞，液位差大于设计值；UQA厂房的除污机、旋转滤网因杂物堵塞造成停运或无法启动时。立即启动应急预案。主要采取人工干预的方式，消除或降低海水系统和设备故障，减少对机组负荷的影响。主要措施有：When the intake open channel has a large quantity of sundries, for instance: straw pole and laver, etc may cause the liquid level difference of dust barrier screen, rough grille and fine grille is greater than the design value; when the water screen and rotation filter screen of UQA factory building is shut down or fails to operate due the blockage of sundries. It is required to initial the emergency preplan immediately, mainly apply the measure of manual intervention, dispel or reduce the failure of seawater system and equipments and reduce the impact on unit load. The main measure is as follows:
利用小船清理取水明渠和拦污网上的杂物，如：麦秸杆等。
Utilize the boat to clear up sundries of intake open channel and dust barrier screen, for instance: Wheat straw, etc.
及时吊出格栅清理。
Hang out the grille to clear up in time.
人工干预除污机、旋转滤网运行。
Operation of the pollutant remover of manual intervention and rotation filter screen;
采用人工方法清洁旋转滤网网板上的杂物。
Adopt the artificial method to clear up the sundries on the mesh of rotation filter screen;
3.2 针对设备存在问题，实施改造和建议处理方案
3.2 Treatment scheme of the existing problem, reconstruction and suggestion of equipment
3.2.1 解决除污机效率低下，故障频繁的主要措施和建议方案
3.2.1 Main measure and proposal scheme to solve the low efficiency and high frequent failure of pollutant remover
高公岛第一道格栅增加不锈钢丝网：原格栅的净间距为150mm，对海水中的漂浮物拦截效果差，按照分级拦截的思路，在格栅上增加了50×50mm的不锈钢丝网，使用行吊吊出格栅，在地面上人工清洗。见图2、图3格栅清洗前的照片。此方法提高了格栅拦污能力，但是在麦收季节、紫菜养殖季节海水污物大量出现，容易发生突然堵塞，机组存在断水风险。
The first grille of Gaogong Island applies the screen of stainless steel: the clear spacing of the original grille is about 150mm, which has a poor blockage result for the floating materials in the sea water. According to the design idea of grading interception, it adds the stainless steel screen of 50×50mm on the grille, applies the overhead hoister to lift the grille and washes on the ground with artificial method. See the photos of Fig. 2 and Fig. 3 before the grille are cleared. This method has improved the blockage performance of grille, however, in harvest season of wheat cultivation, there are large amount of filth appeared in sea water, which may easily cause the sudden blockage and the risk of water cut off of units.
高公岛第二道格栅改为活动式：原格栅的净间距50mm，主要问题是除污机清理出的污物很少。尤其时在格栅上长满贝类海生物情况下，耙斗无法清除这些海生物。另外， 8台格栅中有6台格栅固定在水下，不抽干厂外隧洞的海水无法检修。目前，2#机组3台固定式格栅已经改造成活动式，1#机组3台格栅安排在机组07年11月大修时进行改造。
The second grille of Gaogong Island changes into a moving type: the clear spacing of the original grille is about 50mm. The main problem is the filth removed by the pollutant remover is little, especially when the grille is covered with marine plant of shellfish. The scraper is unable to remove these marine plants. In addition, 6 grilles of 8 grilles are fixed under the water and unable to overhaul without pump out the sea water of tunnel outside the factory. At present, 3 fixed grille of 2# unit have already reconstructed as moving type. 3 fixed grille of 1# unit have arranged for reconstruction in overhauling in November of 07.
UQA厂房的除污机改造：该除污机是俄供产品，目前正在调研国内厂家，做改造的方案研究。
The reconstruction of the pollutant remover of UQA factory building: the pollutant remover is the products of Russia, which is still surveyed and studied by the domestic producer at present for the research reconstruction scheme.
3.2.2 解决旋转滤网动力不足，故障频繁的主要措施和建议方案
3.2.2 The main measures and proposal scheme for solving the insufficient power of rotation filter screen and frequent failure
更换电机和驱动机构：将原齿轮传动系统为链轮传动系统，该传动系统的技术成熟, 链轮传动为硬齿面啮合，耐磨损，强度高，寿命长，维护和检修方便，在国内大量电厂投运行中性能良好、性能稳定。将原有4KW电机改为7.5KW电机，国内类似旋转滤网电机功率通常为7~8KW。目前，两台机组各修改了2台旋转滤网，该传动机构已经运行3月以上，情况良好，满足滤网运行时间要求。
Replace the motor and driving mechanism: replace the transmission system of original gear to transmission system of chain gear which has a mature technology. The chain gear is harden gear surface meshing, which is featured with wear-resisting, high intensity, long service life and convenient for maintenance and overhauling. It has a sound and steady performance during the operation in large number of domestic power stations. Replace original 4KW motor into 7.5KW. Usually the motor power of domestic rotating screen is about 7-8 KW. At present, there 2 unit replace 2 rotating screen respectively. These transmission mechanisms have already operated more than three months, which have a sound condition and meet the relevant requirements of operating time of filter screen.
轴承材料选择建议：俄罗斯旋网的滚轮轴套采用青铜轴套,磨损严重。目前，已经在1PAA32AT101旋转滤网上安装10个不锈钢无油自润滑轴承。该轴承采用英国技术制造的不锈钢耐腐蚀轴承以不锈钢为基体，中间烧结铜粉，表面轧制以聚四氟乙烯为主的低摩擦材料，卷制而成。其使用效果正在验证中。
The proposal of bearing material selection: the roller shaft sleeve of Russia rotating screen applies the bronze axle sleeve which may seriously wear and tear. At present, it have already installed 10 pieces of stainless steel oil-less self-lubricating bearing on 1PAA32AT101 rotation filter screen. This bearing adopts the stainless steel corrosion-resistant bearing of British technology which applies stainless steel as base body, copper powder in intermediate sintering, and low friction material mainly on polytetrafluoroethylene (PTFE) on the surface rolling. The application result is in the process of verification.
侧密封板密封不严，容易卡涩建议处理方式：目前正在讨论使用MC尼龙条密封方式。旋网侧密封板和网板采用MC尼龙条密封进行密封后，间隙小于1毫米，流道净水室与污水室完全被旋网分隔开，能有效阻止污物进入净水区。同时可以消除侧密封板与轨道摩擦变形容易卡涩的问题。
The proposal treatment measure of the tightness of side sealing board and easy trap: discuss the sealing method of the application MC nylon at present. After the side sealing board of rotating screen and mesh board apply MC nylon for sealing, the interval is smaller than 1mm; the channel of water purification chamber is totally separated with the sewage chamber by rotating screen, which may effectively block the filth entering into the water purification area. At the same time, it can eliminate the trap of deformation of side sealing board and track.
建议修改网格板结构：采用圆弧齿合式网板结构，两网板骨架之间采用圆弧齿合。骨架用一系列模具磨牙成形，制造精度高，两块网板之间间隙在运动全过程中小于3mm。满足阻挡杂物需要。
Proposal for changing the structure of screen: adopt the arc tooth shutting type structure of screen; adopt the arc tooth between two frameworks of screen. The frameworks apply series moulds of tooth shaping, which has a high manufacturing precision. The spacing between two screens shall be smaller than 3mm during the course of operating, so as to meet the requirements for blocking the sundries.
图9：建议改造后旋转滤网图
Fig. 9: Rotation filter screen picture after proposal reconstruction
3.3 海生物生长问题和建议解决方案。
3.3 Growth of marine plant and proposing solution
3.3.1对制氯系统进行改造，增加制氯能力
3.3.1Reconstruction of chlorine manufacturing system; promote chlorine manufacturing ability
目前，田湾核电站制氯系统已经投运3~4年，存在制氯设备老化，制氯能力不足问题。需要，尽快更新老化的电极等零部件。另外，目前已经在01UPD厂房增加次氯酸钠溶液储罐，作为制氯设备的补充。从长期考虑，建议增加1~2套制氯设备，作为制氯设备检修时备用。At present, chlorine manufacturing system of Tianwan nuclear power station has already put into operation for 3 years, which has the problem of equipment aging of chlorine manufacturing and insufficient chlorine manufacturing. It is required to replace the spare parts such as electrode as soon as possible. In addition, it has already increased stock tank of sodium hypochlorite solution in 01UPD factory building at present as the supplement of chlorine manufacturing equipments. Consider from the long-term, it is suggested to add 1-2 sets of chlorine manufacturing equipments as the back up of the chlorine manufacturing equipments while overhauling.
3.3.2 建议优化对循环水系统的加氯方式。
3.3.2 Propose to optimize the chlorination feeding method of the circulating water system.
目前，加氯点分别在取水头部和进入UQA厂房的消波池。建议可以考虑在隧洞出口01UPR处增加加氯点，由于厂外隧洞长度在3公里左右，余氯已经很少。有必要在此处增设加氯点，用来防止厂内循环水引水隧洞洞壁海生物生长。取水头部的加氯量应参考日常监测的厂外引水隧洞水头损失情况及时调整。消波池的加氯量可参考设备上海生物生长情况进行调整。同时，监测海水出口残余氯含量，在保证余氯含量满足国家排放标准的前提下，确保加药量对海生物杀灭的有效。
At present, the chlorination feeding point is arranged in the front part of water intake area and wave basin entering into UQA factory building. It is suggested to add the chlorination feeding point at the tunnel export of 01UPR. As the length of tunnel outside the factory is about 3 kilometers, the residual chlorine is little. It is necessary to add the chlorination feeding point here, so as to prevent the growth of the marine plant on the wall of outlet structure of diversion tunnel. The chlorination feeding amount in the front position shall consult daily monitoring of the water head loss of outlet structure of diversion tunnel outside the factory for adjusting in time. The chlorination feeding amount of wave pool shall consult growth of the marine plant for adjusting. Meanwhile, monitor the content of residual chlorine in the sea water and guarantee the efficiency of eliminating effect of marine plant by the chlorination amount base on the premise that the content of chlorination meets the national residual chlorine discharge standard.
3.3.3 设备涂刷防污涂料防止海生物生长
3.3.3 The equipments paint with antipollution coating for preventing the growth of the marine plant
选择有效的防污涂料的作用主要是防止海生物在拦污设备上附着生长，保证拦污设备正常运行，减少水头损失。目前，有多家防污涂料厂家在田湾海域进行长期挂板试验。验证成功的产品，最终将形成田湾核电的技术储备。The function of selecting effective antipollution coating is mainly to prevent the growth of the marine plant adhering on the pollutant remover, guarantee normal running of pollutant remover and reduce water head losses. At present, many antipollution coating producers are tested in the Tianwan for a long time. The successful products shall be the final technological reserve of the Tianwan nuclear power station.
参考文献
References
1、 海水拦污系统设计改进报告
1. The design upgrading report of filth blockage system of sea water
2、 海工系统麦秸杆堵塞时间专项工作报告
2. Special work report of the blockage time of the wheat straw of ocean engineering system
3、 海工系统事故应急预案
3. Accident emergency preplan of ocean engineering system
2012.10.27