高硫煤机组尾部烟道中灰硫分布规律研究

Distribution law of ash and sulfur in tail flue of high sulfur coal-fired unit

为了研究高硫煤机组尾部烟道中灰和硫的分布规律,搭建了高硫煤机组低低温省煤器试验台,测试了低低温省煤器进出口烟道不同截面上的飞灰和SO3质量浓度。试验结果表明:低低温省煤器前水平烟道内飞灰质量浓度下高上低,SO3质量浓度下低上高,灰硫比下高上低;低低温省煤器后水平烟道内SO3质量浓度在不同断面上无明显差别,在垂直烟道内外高内低;当低低温省煤器布置在水平烟道时推荐安全灰硫比为150,布置在竖直烟道时推荐安全灰硫比为100;飞灰对SO3的物理吸附率在15.69%~32.45%,飞灰对SO3的物理吸附率与飞灰的质量浓度成正比,总的SO3质量浓度越高,飞灰对SO3的物理吸附率越低。

To investigate the distribution rules of ash and sulfur in tail flue of high sulfur coal-fired boiler,an ultra low temperature economizer test bench for high sulfur coal-fired power unit was built up,on which the mass concentration of fly ash and SO3 on different sections at inlet and outlet flue of the ultra low temperature economizer were tested.The results show that,the fly ash mass concentration in horizontal flue pipe in front of the ultra low temperature economizer was high at the bottom and low at the top,while the SO3 mass concentration was high at the top and low at the bottom,and the ash-sulfur ratio was high at the bottom and low at the top.There was no significant difference in SO3 mass concentration in different sections of the horizontal flue pipe behind the ultra low temperature economizer.The SO3 mass concentration in vertical flue pipe behind the ultra low temperature economizer was high at the side and low in the center.The recommended safe ash-sulfur ratio is 150 when the ultra low temperature economizer is arranged in horizontal flue pipe and 100 when it is arranged in vertical flue pipe.The physical adsorption rate of fly ash to SO3 was 15.69%~32.45%.The physical adsorption rate of fly ash to SO3 was proportional to the mass concentration of fly ash.The higher the total SO3 mass concentration,the lower the physical adsorption rate of fly ash to SO3.