炼化企业自备电站运行调节对技术经济指标的影响研究

Study on impact of power station operation of refinery on technical economics

炼化企业自备电站的生产运行首先要满足工艺装置的蒸汽需求,当工艺用汽需求出现变化时,汽轮机存在恒进汽量和恒凝汽量两种理想的调节方式。采用某石化企业自备电站热电装置的生产数据,研究了恒进汽量调节方式和恒凝汽量调节方式对热电机组供热比、发电量、发电标煤耗和循环效率等的影响。恒进汽量方式下,汽轮机抽汽量增加会导致低压段蒸汽通流量降低,发电量减小,汽轮机供热量由1 332 TJ增加到2 010 TJ时,供热比由0. 520增加到0. 786,发电标煤耗由337. 9 g/(kW·h)降低到211. 3 g/(kW·h),循环热效率由71. 89%提高到92. 80%。恒凝汽量方式下,汽轮机抽汽量增加会导致高压段蒸汽通流量增加,煤耗量和发电量均增加,当汽轮机供热量由1 332 TJ增加到2 010 TJ时,供热比从0. 564增加至0. 682,发电标煤耗由327. 9 g/(k W·h)下降至263. 5g/(k W·h),循环效率由75. 02%上升到85. 11%。

The primary operation principle for the self-provided power station in the petrochemicals plants is to meet the steam demand of the process units; When there is a change in steam demand of process,there are two ideal regulating modes for the constant steam inlet volume and constant condensate volume. On the basis of analysis of operation modes of steam turbine and application of operation data of the power station of a petrochemical company,the impacts of control modes of constant steam flowrate and condensates on the heat supply ratio,power generation,standard coal consumption and recycle efficiency of the power generation train are studied. Under the constant inlet steam flowrate,the increased extraction steam of steam turbine will lead to the reduction of flowrate of steam in the low-pressure section,and electric power generation will be lowered.When the heat supply of steam turbine is increased from 1 332 TJ to 2 010 TJ,the heat supply ratio is elevated from 0. 520 to 0. 786. The coal consumption for electric power generation is reduced to 211. 3 g/（ kW·h）from 337. 9 g/（ k W·h）. The cycle thermal efficiency is increased from 71. 89% to 92. 80%. Under the constant condensate flowrate,the increased extraction steam flowrate of steam turbine will lead to the increase of steam flowrate in the high-pressure section,and the coal consumption and electric power generation will be increased. When the heat supply of steam turbine is increased from 1 332 TJ to 2 010 TJ,the heat supply ratio is elevated from 0. 564 to 0. 682,the coal consumption for electric power generation is reduced to 263. 5 g/（ k W·h） from 327.9 g/（ kW·h）. The recycle thermal efficiency is increased to 85. 11% from 75. 02%.