200MW机组电站锅炉调峰低负荷水循环安全可靠性

The Reliability on Water Circulation Safety of Peak Shaving Low Load in 200MW Power Plant Boiler

论述了在 2 0 0MW机组电站锅炉所作的调峰低负荷水循环安全在线监测试验。试验目的主要是检验该炉在调峰低负荷运行时水循环的可靠性。试验结果表明 :在 70 %以上电负荷运行时不会出现水循环问题 ;在 5 0 %电负荷滑压运行时水循环流速有些波动 ,但波动的最低值远大于水循环可靠性较差的循环流速界限值 ,仍有足够的流量冷却水冷壁管 ,不致于引起管壁超温 ;在 5 0 %电负荷滑压运行时不宜投水力吹灰器 ;在40 %电负荷下不宜长期运行 ;在 3 0 %电负荷下不宜运行。

This paper has been described on line monitoring test of water circulation safety on 200MW power plant boiler.The test mainly aims at the verification of water circulation reliability during peak shaving low load operation.The experimental results show that no water circulation problem will arise with electric load more than 70%;The water circulation velocity fluctuation of variable pressure operation will appear with 50% electric load,but lowest value of water circulation velocity fluctuation is great more than water circulation velocity threshold with a lowering of water circulation reliability,enough flow rate are capable of cooling water wall tube and are incapable of arising tube wall excess temperature.The ash ejectors are unsuitable operation when variable pressure operation with 50% electric load;The boiler is unsuitable for long term operation when 40% electric load;The boiler is also unsuitable for normal operaiton when 30% electric load.