关键词: 低压缸零出力, 热力系统, 运行背压, 安全性, 经济性, 发电煤耗

Abstract:

This paper introduces the working principle and thermodynamic performance of “zero output technology of low-pressure cylinder”, the influence of variation of operating back pressure on safety and economy of zero output technology of low-pressure cylinde is analyzed in detail. The results show that: when the unit is running under the condition of zero output of low-pressure cylinder, under the main steam flow of 1961t/h condition, the operating back pressure decreased from 0.0049MPa to 0.0029MPa, the volumetric flow of low-pressure cylinder increased from 3387137m³/h to 5449587m³/h, the heating load increased from 862.4MW to 899.0MW, and the coal consumption of unit decreased from 198.7g/(kW·h) to 186.0g/(kW·h); Under the main steam flow of 1861.3t/h condition, the operating back pressure decreased from 0.0049MPa to 0.0029MPa, the volumetric flow of low-pressure cylinder increased from 3391026m³/h to 5446086m³/h, the heating load increased from 821.9MW to 858.6MW, and the coal consumption of unit decreased from 201.7g/(kW·h) to 187.0g/(kW·h). This shows that when the unit is running under the condition of zero output of low-pressure cylinder, through increasing the volumetric flow of low-pressure cylinder, the safety of operation of the low-pressure cylinder will be enhanced, so it is beneficial to improve the safety of operation of the unit, and it can also decrease coal consumption and increase economic benefit through properly reducing the operating back pressure of the unit.

Key words: low pressure cylinder zero output, thermodynamic performance, operating back pressure, safety, economy, coal consumption