Impacts of heat load distribution ratio on energy consumption of extraction steam-high back pressure heating cogeneration unit

doi:10.16085/j.issn.1000-6613.2017-1158

Abstract

Abstract: Using extraction steam-high back pressure heating mode is an effective way to achieve energy cascade utilization and reduce the coal consumption rate in cogeneration units. In a cogeneration power plant,a key issue for energy saving is to determine the optimal value of heat load distribution ratio between heating condenser and peak load heater,based on the power plant energy consumption variation resulting from the heat load distribution ratio between heating condenser and peak load heater. The output power was simulated by using Ebsilon platform,and coal consumption were calculated under conditions with different heat load distribution ratios. Results showed that heat load distribution ratio greatly affects cogeneration unit energy consumption. The variation of coal rate range is from 2.02g/(kW·h) to 5.50g/(kW·h),due to the change of heat load distribution ratio between heating condenser and peak load heater. The relations between the output power and heating condenser heat load distribution ratio varies with heating stages.

Key words: extraction steam-high back pressure heating, energy cascade utilization, energy saving, coal consumption, heat load distribution

摘要： 抽凝-背压供热模式是实现能量梯级利用、降低火力发电煤耗的有效途径，研究不同室外温度下供热凝汽器与尖峰加热器热负荷分配比例对机组能耗的影响，确定最佳热负荷分配比例，是抽凝-背压供热机组节能降耗的核心问题之一。本文利用热网变工况模型及Ebsilon软件仿真，以某310MW抽凝-背压供热机组为研究对象，分析了供热期不同温度下供热凝汽器与尖峰加热器热负荷分配比例不同时机组的发电功率及煤耗。结果表明：对于抽凝-背压热电联产机组，并非供热凝汽器热负荷比例越高而发电功率越高，供热期不同阶段，机组发电功率随供热凝汽器热负荷变化呈现不同规律；相同室外温度下，供热凝汽器与尖峰加热器热负荷分配比例对机组能耗影响很大，凝汽器热负荷比例不同时，其极差最小值和最大值分别为2.02g/（kW·h）和5.50g/（kW·h）。

关键词: 抽凝-背压供热, 能量梯级利用, 节能降耗, 发电煤耗率, 热负荷分配

CLC Number:

TM621

YANG Zhiping, SHI Bin, LI Xiao'en, WANG Ningling. Impacts of heat load distribution ratio on energy consumption of extraction steam-high back pressure heating cogeneration unit[J]. Chemical Industry and Engineering Progress, 2018, 37(03): 875-883.

杨志平, 时斌, 李晓恩, 王宁玲. 热负荷分配比例对抽凝-背压供热机组能耗影响[J]. 化工进展, 2018, 37(03): 875-883.

References

[1] 中华人民共和国国家发展和改革委员会.电力发展"十三五"规划(2016-2020年)[EB/OL].[2017-04-22]. http://www.sdpc.gov.cn/zcfb/zcfbghwb/. National Development and Reform Commission.The thirteenth programme of electric power development(2016-2020)[EB/OL].[2017-04-22].http://www.sdpc.gov.cn/zcfb/zcfbghwb/.
[2] 戈志华,胡学伟,杨志平.能量梯级利用在热电联产中的应用[J].华北电力大学学报(自然科学版),2010,37(1):66-68. GE Zhihua,HU Xuewei,YANG Zhiping.The application of energy step utilize in co-generation[J].Journal of North China Electric Power University(Natural Science Edition),2010,37(1):66-68.
[3] 林振娴,杨勇平,何坚忍.热网加热器在热电联产系统中的全工况分析[J].中国电机工程学报,2010,30(23):14-18. LIN Zhenxian,YANG Yongping,HE Jianren.Analysis on the full conditions of thermal-system heater in the combined and heat power system[J].Proceedings of the CSEE,2010,30(23):14-18.
[4] 林振娴,杨勇平,何坚忍,等.供热机组中压缸排汽参数的确定方法[J].中南大学学报(自然科学版),2011.42(10):3201-3206. LIN Zhenxian,YANG Yongping,HE Jianren,et al.A new method for determining exhaust parameters of medium-pressure cylinder of heating units[J].Journal of Central South University(Science and Technology),2011,42(10):3201-3206.
[5] LI P F,GE Z H,YANG Z P,et al.District heating mode analysis based on an air-cooled combined heat and power station[J].Entropy,2014,16(4):1883-1901.
[6] 张攀,杨涛,杜旭,等.直接空冷机组高背压供热技术经济性分析[J]. 汽轮机技术,2014,56(3):209-212. ZHANG Pan,YANG Tao,DU Xu,et al.The economy analysis of the high back pressure heating technology on direct air-cooled unit[J]. Turbine Technology,2014,56(3):209-212.
[7] 黄治坤,张攀,张艳辉,等.直接空冷机组高背压供热系统及安全运行[J].发电设备,2015,29(3):196-199. HUANG Zhikun,ZHANG Pan,ZHANG Yanhui,et al.Introduction to high back-pressure heating system of direct air-cooling units and the safety operation[J].Power Equipment,2015,29(3):196-199.
[8] 张堙,张寅平,石文星,等.调热器应用:极值原理优化集中供热系统[J]. 工程热物理学报,2015(5):941-944. ZHANG Yin,ZHANG Yinping,SHI Wenxing,et al.Application of heat adaptor:thermodynamic optimization for central heating system through extremum principle[J]. Journal of Engineering Thermophysics,2015(5):941-944.
[9] 徐翔,王远超,张博.基于喷射式热泵的热电联产供热系统[J].化工学报,2014,65(3):1025-1032. XU Xiang,WANG Yuanchao,ZHANG Bo.Cogeneration heating system based on ejector heat pumps[J].CIESC Journal,2014,65(3):1025-1032.
[10] 刘媛媛,隋军,刘浩.燃煤热电厂串并联耦合吸收式热泵供热系统研究[J].中国电机工程学报,2016,36(22):6148-6155. LIU Yuanyuan,SUI Jun,LIU Hao.Research on heating system of serial-parallel coupling absorption heat pump for coal fired power plants[J].Proceedings of the CSEE,2016,36(22):6148-6155.
[11] 冯澎湃,王宁玲,杨志平,等.直接空冷高背压供热机组的梯级供热特性与冷端变工况协同优化[J].中国电机工程学报,2016,36(20):5546-5554. FENG Pengpai,WANG Ningling,YANG Zhiping,et al.Cascade heating characteristics and off-design collaborative optimization of direct air-cooled high pressure heat supply power units[J].Proceedings of the CSEE,2016,36(20):5546-5554.
[12] 赵世飞,戈志华,陈浩,等. 增设无再热汽轮机热电联产系统节能研究[J]. 中国电机工程学报,2016,36(23):6441-6447. ZHAO Shifei,GE Zhihua,CHEN Hao,et al.Energy saving research of a novel combined heat and power system integrating with a non-reheat steam turbine[J].Proceedings of the CSEE,2016,36(23):6441-6447.
[13] LUND H,WERNER S,WILTSHIRE R,et al.4th Generation district heating(4GDH)[J].Energy,2014,68:1-11.
[14] FREDERIKSEN S,WERNER S.District heating and cooling[M].Sweden:student literature,2013.
[15] ANGRISANI G,MINICHIELLO F,ROSELLI C,et al.Experimental investigation to optimise a desiccant HVAC system coupled to a small size cogenerator[J].Applied Thermal Engineering,2011,31(4):506-512.
[16] 李沛峰.基于绿色供热的热电联产低温直供模式研究[D].北京:华北电力大学,2015. LI Peifeng.Research on low temperature district heating of combined heat and power based on green heating[D].Beijing:North China Electric Power University,2015.
[17] 韩中合,李鹏.低温省煤器对凝汽器真空及机组热经济性影响[J]. 化工进展,2015,34(11):4114-4119. HAN Zhonghe,LI Peng.Impacts of adding low-temperature economizer on condenser vacuum and thermal economic[J]. Chemical Industry and Engineering Progress,2015,34(11):4114-4119.