济南黄台电厂循环水吸收式热泵供热系统研究

发布时间：2018-03-24 01:26

本文选题：电厂循环水　切入点：热电联产　出处：《哈尔滨工业大学》2017年硕士论文

【摘要】：火电厂循环冷却水余热作为一种低品位的热源,若直接将其排放到大气环境中,是一种非常大的能源浪费,应当采取有效的措施,设法减少冷源余热损失,提高热电联产机组的整体热效率。随着热泵技术的迅速发展和逐渐成熟,利用热泵可以将循环冷却水中的低品位热能转化成高品位热能,同时还能够提高机组的效率和供热能力。吸收式热泵在中小型热电联产机组中的应用已较为普遍,但是在300MW的大型机组中应用较少,本文以济南黄台电厂2×300MW热电联产机组为例,对现有系统进行了用能分析,确定了电厂的主要能量损失,分析了回收冷却水余热的节能潜力。通过比较各种回收电厂循环水余热的技术措施,确定采用吸收式热泵供热是回收电厂循环水余热的最佳技术措施。本文通过对黄台电厂热网的分析,确定了以循环冷却水作为低温热源,以汽轮机的五段抽汽作为驱动汽源,使用热泵机组提高供热管网回水温度的改造思路。在此基础上,对热泵蒸汽系统及配套疏水系统、厂区内热力管网系统以及循环冷却水系统提出了具有针对性的改造方案,对吸收式热泵在大型热电联产机组中的应用进行了有益的探索。通过选取供暖季工况均值,以发电量和供热量为标准,对发电机组带热泵运行和不带热泵运行两种方式下的热经济指标进行了分析。在供热量以及发电量相同的情况下,比较了热效率、供热煤耗、发电煤耗以及总煤耗等参数,分析了使用热泵机组供热的经济性。最后,通过费用年值法和动态投资回收期法对改造方案的经济效益行了评估,确定了吸收式热泵回收循环水余热改造项目的可行性。项目投运后,从第5年开始实现盈利,在现有供热面积不变的情况下,全厂热效率可由64.837%提高到68.99%,每年可节约标煤23940吨,减排二氧化碳62728吨,二氧化硫203.5吨,氮氧化物177.1吨,粉尘359.1吨,灰渣6224.4吨。因此,该项目具备可行性,具有可观的经济效益、环保效益和社会效益。
[Abstract]:The waste heat of circulating cooling water in thermal power plant as a low-grade heat source, if it is discharged directly into the atmospheric environment, is a very big energy waste. Therefore, effective measures should be taken to reduce the waste heat loss of the cold source. With the rapid development and maturity of heat pump technology, the low grade heat energy in circulating cooling water can be converted into high grade heat energy by using heat pump. At the same time, it can also improve the efficiency and heating capacity of the unit. Absorption heat pump has been widely used in small and medium-sized cogeneration units, but it is seldom used in large 300MW units. This paper takes the 2 脳 300MW cogeneration unit of Jinan Huangtai Power Plant as an example. The energy use analysis of the existing system is carried out, the main energy loss of the power plant is determined, and the energy saving potential of the waste heat recovery of the cooling water is analyzed. By comparing various technical measures for recycling the waste heat of the circulating water in the power plant, It is determined that absorption heat pump heating is the best technical measure to recover the waste heat of circulating water in power plant. Through the analysis of the heat network of Huangtai Power Plant, it is determined that the circulating cooling water is used as the low temperature heat source, and the steam extraction of the steam turbine is used as the driving steam source. On the basis of the idea of improving the backwater temperature of heat supply pipe network by using heat pump unit, this paper puts forward the corresponding retrofit scheme for the heat pump steam system and associated drainage system, the heat pipe network system and the circulating cooling water system in the factory area. The application of absorption heat pump in large heat and power cogeneration unit is explored. By selecting the mean value of heating season, the standard of energy generation and heat supply is taken as the standard. In this paper, the thermal economic indexes of heat pump operation with and without heat pump are analyzed. The thermal efficiency, coal consumption of heating, coal consumption of power generation and total coal consumption are compared under the same conditions of heat supply and electricity generation. The economy of using heat pump unit to heat supply is analyzed. Finally, the economic benefit of the retrofit scheme is evaluated by the annual cost method and the dynamic investment payback period method. The feasibility of the project of recovering waste heat from circulating water by absorption heat pump is determined. After the project is put into operation, the profit will be realized from the fifth year. Under the condition that the existing heating area is unchanged, the thermal efficiency of the whole plant can be increased from 64.837% to 68.9937%, and the standard coal can be saved 23940 tons per year. 62728 tons of carbon dioxide, 203.5 tons of sulfur dioxide, 177.1 tons of nitrogen oxides, 359.1 tons of dust and 6224.4 tons of slag. Therefore, the project is feasible and has considerable economic, environmental and social benefits.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU83

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