燃气—蒸汽联合循环热电厂采暖季运行优化分析

发布时间：2018-02-22 05:18

本文关键词： 燃气-蒸汽联合循环机组供热运行热电曲线效率耗气量　出处：《天津大学》2014年硕士论文　论文类型：学位论文

【摘要】：我国燃气-蒸汽联合循环供热机组的应用起步较晚,在较多设计、算法等方面技术尚未完全掌握,本文针对我国天然气产量较低,燃气发电成本较高等不利因素,开展了以天津陈塘庄热电厂煤改气搬迁工程燃气-蒸汽联合循环机组作为研究对象,依据热平衡图及机组热电曲线计算出采暖季日电负荷及耗气量等参数,并以各种工况下日热负荷量为依据,分别计算采暖季机组“二拖一”运行模式下,背压工况及抽凝工况天然气耗气量,通过比较对照,对采暖季运行方式进行热力学分析探讨,给出了较优化的机组运行模式,保证天然气的优质利用,使热电厂供热效率达到最高。本工程发电燃料采用洁净的天然气。引进国外先进的燃气-蒸汽联合循环设备及自动化控制系统。联合循环机组毛热效率达到58.4%,冬季采暖期达到87.04%,本工程设计尽最大可能提高供热能力。汽轮机采用“二拖一”背压机+SSS离合器的供热方案,冬季按照背压机运行,中压缸的全部排汽用于供热,非采暖期按照凝汽式运行,此种机组配置没有低压缸最小冷却蒸汽流量的要求,可使汽轮机供热量能达到最大化,本工程在背压供热的基础上采用烟气热网水余热加热器进一步增加供热量,提高供热能力。总的对外供热能力不低于1254MW。在保证供热工况下的热耗率为4136kJ/kWh。本文经过计算分析,在保证采暖季供热量的基础上,制定出机组“一拖一”和“二拖一”运行模式下背压及抽凝工况天然气耗气量的“气耗曲线”,以便于电厂采暖季期间的经济运行,燃气集团的合理调度,取得较好的预期效果。
[Abstract]:The application of gas-steam combined cycle heating unit in our country started late, and has not been fully mastered in many aspects, such as design, algorithm and so on. This paper aims at the unfavorable factors such as low natural gas output and high cost of gas power generation in China. Taking the gas-steam combined cycle unit as the research object, the daily power load and gas consumption of the heating season are calculated according to the heat balance diagram and the thermoelectric curve of the unit. On the basis of the daily heat load under various working conditions, the natural gas consumption under the operation mode of "two tugs and one" in the heating season is calculated, and the natural gas consumption under the backpressure condition and the condensing condition is calculated, and the thermodynamic analysis of the operation mode in the heating season is carried out through comparison and comparison. In order to ensure the high quality utilization of natural gas, the operation mode of the unit is optimized. The heating efficiency of the thermal power plant is maximized. Clean natural gas is used as the fuel for power generation in this project. Advanced gas-steam combined cycle equipment and automatic control system are introduced. The gross heat efficiency of the combined cycle unit reaches 58.4and winter. The heating period reaches 87.044.The project is designed to improve the heating capacity to the maximum extent possible. The steam turbine adopts the heating scheme of SSS clutch of "two towing and one" backpressure machine. In winter, all the exhaust steam of the medium pressure cylinder is used for heating, and in the non-heating period, the unit is operated in accordance with the condensed steam type. There is no requirement for the minimum cooling steam flow rate of the low pressure cylinder, and the heat supply of the steam turbine can be maximized. On the basis of backpressure heating, this project adopts waste heat heater of flue gas heating network to further increase heat supply and improve heating capacity. The total external heating capacity is no less than 1254MW. The heat consumption rate is 4136kJ / kWh. the heat consumption rate is 4136kJ / kWh. the heat consumption rate is calculated and analyzed in this paper. On the basis of ensuring heat supply in heating season, the "gas consumption curve" of unit "one tow one" and "two towing one" operation mode and natural gas consumption under condensing condition is worked out, so as to facilitate the economic operation of power plant during heating season. The reasonable dispatch of gas group has achieved good expected effect.
【学位授予单位】：天津大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM611.31

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