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1、火电厂干湿混合式冷却塔节能、节水技术洛阳万山高新技术应用工程有限公司地址：洛阳市凯旋西路29号建设大厦东座16层 联系人：曲万山 邮编：471000电话： 037963940258 63901966 13903793181 传真： 037963913080网站：http:/ E-mail: 火电厂干湿混合式冷却塔节能、节水技术节水在火电厂有着越来越重要的地位。热力发电厂的排汽采用干湿混合是符合可持续发展战略的有前途的发电技术，在我国这项技术尚未得到人们的关注。对电厂排汽采用干、湿混合进行了深入的研究，以便使干、湿混合其显著的节水性、科学的节能性及环保性能够在我国干旱缺水的北方地区得到应用。
2、使排汽冷却系统的配置更趋完善化、合理化。水是人类社会生存和发展不可替代的资源，是经济社会可持续发展的基础。当代人类生活水准同能量和淡水的消耗是息息相关的。全球人口的剧增使能源和淡水消耗量难以估算。我国将进入严重缺水期，水资源的严重短缺，将严重制约着经济发展。为保证国民经济的可持续发展，合理使用淡水资源和有效节约淡水、保护现存珍贵的淡水资源，就是保护我们人类生存的必要条件。为推动循环经济发展，建设资源节约型社会，火力发电厂高耗能、高耗水、粗放型经营越来越不适合经济发展的需要，做为用水大户之一的火力发电厂,其节水工作更应在科技力量的推进下走在社会的前列。火力发电厂汽轮机组排汽冷却系统采用干湿混合冷
3、却系统可推动节能降耗、节水工作的开展。一、目前我国火电厂冷却系统工作现状分析节能、节水与环保将是我国火电发展的主题，源于水资源的紧迫性，缺水地区火电厂空冷技术已得到应用。空冷以其显著的节水效果被人们所关注，空冷机组冷却系统本身可节水97以上，全厂性节水约65。一般13的水可建设100万千瓦湿冷机组，而建设100万千瓦空冷机组只需0.353的水。因此相同数量的水可建设的空冷机组规模比湿冷机组可建设的规模大三倍，这充分显示了空冷技术节水的优越性。目前我国用于发电厂的冷却系统有二种：一种为空冷系统；另一种为湿冷系统。空冷系统有三种形式：直接空冷系统、带表面式凝汽器的间接空冷系统（海勒式）和带喷射式（
4、混合式）凝汽器的间接空冷系统（哈蒙式）。直接空冷、（海勒式与哈蒙式间接空冷系统）虽然节水效果较好，但由于其高背压和现有冷却水塔冷却面积所限，夏季会造成出力的限制。配有空冷系统的空冷机组，一次性投资较高，发电标准煤耗较高，夏季也要限制机组出力。故空冷机组节水能力强但全年都在不经济的背压下运行，造成很大能源浪费，故经济性不高。湿冷系统就是传统的湿冷机组，虽然它的冷却效果好，经济性高，上述问题较小，但却需要消耗大量的循环水（火力发电厂70%消耗在这里）。在北方缺水地区新建电厂已受限制。二、一种新的冷却系统的提出-干湿混合冷却系统那么有没有一种冷却系统兼容二种冷却系统之长呢？答案是肯定的。电厂采用空冷
5、（干冷）、水冷（湿冷）的干湿混合冷却系统是一种解决上述两方面不中足的可行性方案，是火力发电厂机组冷却系统的又一种形式。它的节能、节水、环保优于上述两种系统单独运行。干湿混合冷却系统既能发挥空冷机组节水的优越性，又能保持湿冷机组节约投资，经济性高，夏季出力不限制，适应机组变工况运行的优点。干湿混合冷却系统弥补了空冷系统、湿冷系统的缺陷，是一种有待发展的新技术。三、 电厂汽轮发电机组干湿混合冷却塔工程简介 （一）、发电厂排汽凝结系统介绍（冷却系统）发电厂汽轮机排汽的余热主要通过蒸发散热和对流换热两种方法散发到大气中的。1、电厂汽轮机排汽凝结是用循环水的对流换热交换余热的，而循环水的热量再经过散热设
6、备（冷却塔或其它冷却方式）的蒸发散热和对流换热把余热带入大气中，冷却后的水温取决于冷却塔性能及大气湿球温度，冷却塔出水温度一般在1533C之间，汽轮机背压在511kPa之间。2、干冷（空冷）发电厂汽轮机排汽凝结（不论有无中间介质）是用空气对流换热交换余热的，排汽的余热是经过散热设备（空冷塔或空冷凝汽器）与空气对流换热的方式将余热带入大气中的，干冷系统冷却后温度是趋近大气干球温度的，由于整个换热过程是在密闭的环境下完成的，所以工质流失少，节水效果好，但传热效果受环境温度影响较大。空冷汽轮机的设计背压高于湿冷系统汽轮机的设计背压，而且背压在运行中随环境温度的变化而变化。间接空冷系统的水温与大气干球
7、温度密切相关。当大气干球温度变化40C，冷却水温也变化约40C。当工作背压在518kPa时，汽轮机能达到额定功率；汽轮机在最高背压25.5kPa时，要减负荷。直接随着高背压及背压大的变化，对空冷汽轮机的安全运行影响很大。（二）二种冷却系统经济技术分析1、湿冷系统发电厂循环水的冷却是靠喷水雾化放热带入大气中的，湿冷系统冷却后温度是趋近大气湿球温度，传热效果好，效率较高。但湿冷塔的蒸发损失、水雾损失、排污损失、风吹损失和软化水更新需补充大量的新鲜水（湿冷机组主要耗水地方）消耗掉大量的水资源，这也是缺水地区新建电厂受限的原因。目前我们可行的节水方式为湿式冷却塔循环水弱酸处理，提高冷却塔浓缩倍率，优化
8、循环排污水净化技术，实现污水零排放，为节水起到一定效果。2、干冷系统发电厂循环水是靠空气的对流换热把余热带入大气中的，干冷系统冷却后温度是趋近大气干球温度的。汽轮机背压在运行中随环境温度的变化而变化，空冷系统的汽轮机背压较高，变化范围大，多在1050kPa之间。特别夏季，由于室外温度高，循环热水在空冷塔散热器中不能得到有效的冷却，进出口水温差较小，末级热量不能得到及时有效的转移，致使系统真空偏低，背压也升高。背压的升高将引起：机组出力降低、相对蒸汽流量减少、叶根脱流区扩大、末级蒸汽出现滞流、转向倒流、叶根部出现负反动度、增大叶片的动应力，甚至导致叶片的断裂损坏威及到机组的安全运行。（三）干湿混
9、合冷却塔传热分析与节能途径干湿混合冷却系统是靠水的蒸发散热和对流换热把余热带入大气，对流换热系数的大小与换热过程中的许多因素有关，它不仅取决于流体的物理性质（，Cp等），换热表面的形状与布置，而且还同流速有密切的关系。火力发电厂冷却系统的主要冷却介质是水或空气。湿冷时，管外为冷却水，管内为工质水；空冷时，管外为空气，管内为工质水，冷却过程是系统排放的废热与环境的能量交换过程。由于水的利用受到各种因素限制，而水作冷却介质的传热系数为1762W/(m2.K)，空气作冷却介质的传热系数为62W/(m2.K)。传热系数表证了传热过程的强烈程度，传热系统数越大，传热过程越强，热阻越小。由于空冷系统传热系
10、数小，传热效果差，其机组经济性较差。湿冷系统传热系数大，传热效果好，其机组经济性较高，但需消耗大量新鲜水。干湿混合冷却系统增大了传热系数，靠水的蒸发散热和对流换热把余热带入大气，从而实现了空冷节水，湿冷高经济性的完美组合。（四）干湿混合冷却塔原理干湿混合冷却系统是集湿式冷却塔和空冷塔的优点，充分利用水经湿冷水塔冷却时与空气的热交换来增加空气湿度，提高吸热能力使空气干球温度降低的特点，对空气冷却器进行冷却。它是这样实现的：循环水出口水首先进入铜铝复合散热器与高湿度、低干球温度的空气逆流换热，冷却了散热器中的水；同时，铜铝复合散热器加热了高湿度的空气，使其密度减小，降低了冷水塔风筒内的压力，提高了
11、空气升腾的速度、增加了冷却塔的冷却进风量。经过散热器预冷的水温度降低，再经过喷淋装置分布到冷却水塔的冷却热交换填料上，冷却散热，减少了水的蒸发，降低了空气的干球温度，又使得空气冷却器有好的冷却换热效果。由于喷淋装置分布在冷却水塔冷却热交换填料上的水温度低，因此，可减少水的蒸发量，从而减少了水的散失损失和排污损失，形成了充分利用空气干、湿球温度，互补散热的干湿混合式冷却塔。干湿混合冷却系统在夏季气温最高时，干湿混合运行达到机组满发；冬季气温降低（或夜间低负荷时）空冷运行。复合散热器的合理布置，使冷却塔结构紧凑，无需防冻。为保证冷却塔喷嘴高效运行，一台循环泵采用变频调节，随着排汽温度的降低，喷嘴从
12、外层到内层逐步关闭，以满足喷嘴压力的要求，同时循环泵变频技术的采用降低耗能。（五）安全性分析由于大机组在调峰时具有时间短、负荷响应快的特点，这就加剧了凝汽器铜管的热应力，运行中易出现铜管胀口、铜管腐蚀或由于振动造成铜管损坏，铜管破损导致了凝结水被污染。干湿混合冷却系统采用混合凝汽器，其循环水与凝结水标准相同，将端差由凝汽器内转移到凝汽器外就可避免以上问题的发生，为机组的安全提供了可靠的保证，不会造成凝结水污染现象。避免了空冷机组由环境温度变化而引起的排汽温度的变化，相同条件下，具有较高的排汽温度和较高的背压。空冷汽轮机排汽背压直接受的影响，而环境温度变化频繁，变化幅度大。如：一年气温从27.5
13、上升到32，对应的排汽温度为28.665.4，相应的排汽背压为3.92Kpa25.50Kpa。这样大的排汽背压和排汽温度的变化范围，汽轮机低压缸的热变形会受到影响，造成与低压缸联接在一起的轴承座标高发生变化，其结果会改变各轴承原有的负荷分配比例，使有的轴承受力增大，有的荷重减轻，荷重大的轴承会增大油膜刚度和阻尼系数，使轴瓦运行稳定性增强。但过大的轴承载荷会使油温和瓦温升高，严重时会损坏轴瓦；载荷过轻，比压太小的轴承稳定性变差，严重时会失去稳定，甚至发生油膜自激振动，造成严重的振动事故；支承标高变化还会改变转子的临界转速、振型曲线及原有的平衡状态，破坏已经调整好的动静间隙，可能引起动静摩擦振动。
14、因此，空冷汽轮机高背压高排汽温度对机组安全运行是不利的。我国水资源的短缺，在北方地区发展火电事业，开发干湿混合冷却系统展示了广阔的前景。三、实施干湿混合冷却系统工程的技术比较和意义（一）汽轮机排汽三种冷却系统的比较。A、汽轮机排汽湿冷系统：1. 机组经济性高（冷却水出口温度向大气湿球温度逼近）；2. 保持真空能力强；3. 厂用电率低（与空冷比较）；4. 大容量机组可采用汽动给水泵降低厂用电消耗；5. 消耗水资源大（需补充大量新鲜水）；6. 凝结水易被污染；7. 凝汽器铜管（或钢管）易结垢，造成端差增大；8. 有大气雾气团；9. 冬季有30冷却水系统短路进行防冻；10.投入的胶球清洗装置存在收球
15、率低。B、汽轮机排汽空冷系统：1. 具有显著的节水性；2. 无大气雾气团；3. 凝结水不易被污染；4. 经济性差（冷却水出口温度向大气干球温度逼近）；5. 保持真空能力差；6. 夏季炎热时需限制机组出力；7. 冬季防冻，采用部分冷却系统停运或关小百叶窗等措施；8. 大容量机组无法采用汽动给水泵；9. 厂用电消耗大；10.设计背压比湿冷高很多，冬季运行也不经济；11.冷却性能受环境影响很大，机组排汽压力变化大，安全性较差，易发生机组振动；12.末级叶片需特殊设计，机组运行中调节不当易造成脱流和阻塞背压。C、汽轮机排汽干湿混合冷却系统：1. 机组经济性高（同湿冷）；2. 保持真空能力强；3. 基本
16、无大气雾气团；4. 夏季炎热时不需限制机组出力，冬季不需减少冷却水系统进行防冻；5. 节水效果显著；6. 机组端差小（与湿冷比较）；7. 凝结水不易污染；8. 机组安全性、可靠性高；9. 调节灵活、方便； 10.对于大容量机组同样可以采用汽动给水泵；11.厂用电消耗较高（同湿冷比较）；12.现有湿冷系统易改造。（二）实施实施干湿混合冷却系统工程的意义社会对能源的需求越来越大，能源问题已成为国家发展战略的重要组成部分。我国能源有效利用率仅为33，与世界先进水平差10个百分点，是世界上产值能耗最高的国家之一，也就是说我国的节能降耗潜力很大。火电厂实现节能降耗目前最好的思路是从提高能源使用效率入手。
17、干湿混合冷却系统混合塔的优点就是：最有效地、合理优化系统配置，集节约用水、节约能源、冬季没有雾气团、没有噪声、易在现有湿冷机组改造于一身的火电厂冷却系统。目前建设一座百万级电站约58亿左右，投资回收需18年左右，而将目前湿冷机组改造为干湿混合冷却系统，使其有背压同湿冷，经济性高于湿冷机组，节水达65左右的节能型机组，按水价2.3元/吨计算，相当于一年仅节水就节约5760万元。随着电力市场的改革，厂网分离，竞价上网势在必行。采用干湿混合的冷却系统其节水、节能、环保、安全的优越性必将会引起全社会的广泛关注。以全国现在建火电机组及老机组湿冷冷却塔改造为干湿混合冷却塔为例，按节水65计算，若采用本技术
18、则一年可节水数亿吨，节约煤资源数万吨。对降低电力企业生产成本，提高经济效益。对全国节水、节能及环保都具有不可低估的意义。55（英文版 ） Two regulations promulgated for implementation is in the party in power for a long time and the rule of law conditions, the implementation of comprehensive strictly strategic plan, implementation in accordance with the rules and di
19、scipline to manage the party, strengthen inner-party supervision of major initiatives. The two regulations supporting each other, the adhere to a positive advocate, focusing on morality is of Party members and Party leading cadres can see, enough to get a high standard; around the party discipline,
20、disciplinary ruler requirements, listed as negative list, focusing on vertical gauge, draw the party organizations and Party members do not touch the bottom line . Here, the main from four square face two party rules of interpretation: the first part introduces two party Revised regulations the nece
21、ssity and the revision process; the second part is the interpretation of the two fundamental principles of the revision of laws and regulations in the party; the third part introduces two party regulations modified the main changes and needs to grasp several key problems; the fourth part on how to g
22、rasp the implementation of the two regulations of the party. and revised the necessity and revised history of the CPC Central Committee the amendment to the Chinese Communist Party members and leading cadres honest politics several guidelines and column 1 by 2015 to strengthen party laws and regulat
23、ions focus. Two party regulations revision work lasted a Years, pooling the wisdom of the whole party, ideological consensus, draw historical experience, respect for the wisdom of our predecessors, which reflects the unity of inheritance and innovation; follow the correct direction, grasp the limite
24、d goals, adhere to the partys leadership, to solve the masses of the people reflect a focus on the problem. The new revision of the and , reflects the partys 18 and the eighth session of the third, the spirit of the fourth plenary session, reflecting the experience of studying and implementing the G
25、eneral Secretary Xi Jinping series of important speech, reflects the partys eighteen years comprehensive strictly practice. (a) revised two regulations of the party need of in based on revised, the promulgation and implementation of January 2010, to strengthen the construction of the contingent of l
26、eading cadres play an important role. But with the party to manage the party strictly administering the deepening, has not been able to fully meet the actual needs. Content is too complicated, eight prohibition, 52 are not allowed to hard to remember, and also difficult to put into practice; the sec
27、ond is concisely positive advocated by the lack of prohibited provisions excessive, no autonomy requirements; the third is banned terms and discipline law, both with the party discipline, disciplinary regulations repeat and Criminal law and other laws and regulations repeat; the fourth is to clean t
28、he theme is not prominent, not for the existing problems, and is narrow, only needle of county-level leading cadres above. is in 1997 based on revision, in December 2003 the promulgation and implementation, to strengthen the construction of the party play very important role. Along with the developm
29、ent of the situation, which many provisions have been unable to fully meet the comprehensive strictly administering the practice needs. One is Ji law, more than half of the provisions and criminal law and other countries laws and regulations Repetition; two is the political discipline regulations is
30、 not prominent, not specific, for violation of the party constitution, damage the authority of Party Constitution of misconduct lack necessary and serious responsibility to pursue; third is the main discipline for the leading cadres, does not cover all Party members. Based on the above situation, ne
31、ed to and the two is likely to be more relevant regulations first amendment. By revising, really put the authority of Party discipline, the seriousness in the party tree and call up the majority of Party members and cadres of the party constitution of party compasses party consciousness. (II) two pa
32、rty regulations revision process the Central Committee of the Communist Party of China attaches great importance to two regulations revision . Xi Jinping, general books recorded in the Fifth Plenary Session of the eighth session of the Central Commission for Discipline Inspection, on the revised reg
33、ulations made clear instructions. According to the central deployment, the Central Commission for Discipline Inspection from 2014 under six months begin study two regulations revision. The Standing Committee of the Central Commission for Discipline Inspection 4 review revised. Comrade Wang Qishan 14
34、 times held a special meeting to study two regulations revision, amendment clarifies the direction, major issues of principle, path and target, respectively held a forum will listen to part of the province (area) secretary of the Party committee, Secretary of the Discipline Inspection Commission, pa
35、rt of the central ministries and state organs Department The first party committee is mainly responsible for people, views of experts and scholars and grassroots party organizations and Party members. Approved by the Central Committee of the Communist Party of China, on 7 September 2015, the general
36、 office of the Central Committee of the Party issued a notice to solicit the provinces (autonomous regions, municipalities) Party, the central ministries and commissions, state ministries and commissions of the Party (party), the General Political Department of the military, every 3 people organizat
37、ion of Party of two regulations revision opinion. Central Commission for Discipline Inspection of extensive solicitation of opinions, careful study, attracting, formed a revised sent reviewers. In October 8 and October 12, Central Committee Political Bureau Standing Committee and the Political Burea
38、u of the Central Committee After consideration of the two regulations revised draft. On October 18, the Central Committee of the Communist Party of China formally issued two regulations. Can say, two laws amendment concentrated the wisdom of the whole party, embodies the party. Second, and revision
39、of the basic principles of two party regulations revision work and implement the partys eighteen, ten eight plenary, the spirit of the Fourth Plenary Session of the Eleventh Central Committee and General Secretary Xi Jinping important instructions on the revised and , highlighting the ruling party c
40、haracteristics, serious discipline, the discipline quite in front of the law, based on the current, a long-term, advance as a whole, with Bu Xiuding independent and . Main principle is: first, adhere to the party constitution to follow. The constitution about discipline and self-discipline required
41、specific, awaken the party constitution of party compasses party consciousness, maintaining the authority of the constitution. General Secretary Xi Jinping pointed out that no rules, no side round. Party constitution is the fundamental law, the party must follow the general rules. In early 2015 held
42、 the eighth session of the Central Commission for Discipline Inspection Fifth Plenary Session of the 16th Central Committee, Xi Jinping again pointed out that constitution is the party must follow the general rules, but also the general rules. the revision of the and is Method in adhere to the regul
43、ations established for the purpose of combining rule of virtue is to adhere to the party constitution as a fundamental to follow, the constitution authority set up, wake up the party constitution and party rules the sense of discipline, the party constitution about discipline and self-discipline spe
44、cific requirements. 4 second is to adhere to in accordance with the regulations governing the party and the party. The Party of rule of virtue de, mainly refers to the partys ideals and beliefs, excellent traditional style. The revised the closely linked to the self-discipline, insisting on the posi
45、tive initiative, for all members, highlight the vital few, emphasized self-discipline, focusing on the morality, and the majority of Party members and the ideological and moral standards. The revised Ji method separately, Ji, Ji Yan to Method, as a negative list, emphasizing the heteronomy, focusing
46、 on vertical gauge. Is this one high and one low, a positive reaction, the strict party discipline and practice results transformation for the integration of the whole party to observe moral and discipline requirements, for the majority of Party members and cadres provides benchmarking and ruler. Th
47、ird, insist on to. In view of the problems existing in the party at the present stage, the main problems of Party members and cadres in the aspect of self-discipline and abide by the discipline to make clearly defined, especially the partys eighteen years strict political discipline and political rules, organization and discipline and to