湿法脱硫后烟气中SO3/硫酸雾测试方法的试验

在自行设计和搭建的模拟湿法脱硫烟气系统中,研究了基于控制冷凝法原理的SO_3/硫酸雾采集装置对湿法脱硫后SO_3/硫酸雾的捕集性能,重点考察了螺旋管与石英棉冷凝温度、采样枪温度、采样流量、采样时间和SO_3/硫酸雾质量浓度对SO_3/硫酸雾捕集性能的影响。结果表明,在研究范围内,湿法脱硫后SO_3/硫酸雾采集装置优化的操作参数为:螺旋管及石英棉冷凝温度95℃,采样枪温度280℃,采样流量17 L/min,采样时间30 min。SO_3/硫酸雾质量浓度较高时,螺旋冷凝管对SO_3/硫酸雾的捕集起主要作用,其捕集的SO_3/硫酸雾比例在75.8%~80.8%,远高于螺旋冷凝管与石英棉捕集SO_3/硫酸雾的比例;SO_3/硫酸雾质量浓度较低(约1mg/m3)时,采样枪对SO_3/硫酸雾的捕集起主要作用,其捕集SO_3/硫酸雾的比例大于50%。

Experimental study of the method for testing the SO3/H2SO4 mist in the downwardly flowing stream of the wet flue desulfurization gas

The paper is to investigate the effects of a series of key influential factors on the capture performance of the sampling device,such as the condensation temperature of the spiral tube and the quartz wool,the temperature of the shooting guns,the flow gas rate,the sampling time and concentration of the SO3/H2SO4 mist by using a self-designed and constructed flue gas system with a simulated wet flue gas desulfurization (WFGD) device on the basis of the control condensation method (CCM).The results of its study indicate that the optimal operating parameters of the sampling device under study can be shown as follows:the condensation temperature of the spiral tube and quartz wool should be coming up at about 95 ℃,and the sampling gun ought to increase its temperature by 280 ℃ when shooting,with the sampling flow gas rate being at 17 L/min during the sampling time of 30 min,with the sampling mist downstream of WFGD rifled with SO3/H2SO4.For a higher concentration level of the mist SO3/H2SO4,the spiral tube tends to make a major contribution to its capture,whereas the SO3/H2SO4 mass to be captured in the spiral tube can approximately increase and go up to a relative percentage of 75.8％-80.8％,which is expected far greater than that in the sampling gun and quartz wool.At a lower concentration level of SO3/H2SO4 mist (1 mg/m3),the sampling gun can also make its major contribution to the capture,with its relative mass percentage of SO3/H2SO4 to be captured in the gun being just over 50％.As a result,in the case of the wet flue gas containing a lower concentration level of SO3/H2SO4 mist,especially,for SO3 sampling at the WESP outlet,the total SO3concentration should include the collected SO3/H2SO4 in the internal surface of the gun.Thus,the given paper can be expected to provide valuable data and statistical information for accurate measurement of SO3/H2SO4 concentration,based on the control condensation method (CCM),in the condition of humidity saturated flue gas downstream of the gas desulfurization in the above mentioned device.