不同气体成分下高温直流放电特性

为了提高静电除尘器用于高温气体除尘时的运行可靠性及稳定性，采用小型线管式高温静电除尘实验装置，对CO2、N2、空气及热解煤气4种气体在300-700℃下的直流放电特性进行研究.结果表明，随温度升高，放电电流增大，起晕电压及击穿电压下降，击穿电压降低更快；温度对电负性气体CO2、空气放电特性的影响大于非电负性气体N2.高温热解煤气放电会发生生成C和H2O的化学反应，放电特性与N2更相似，但与之不同的是，当电源电压较低时，因煤气中含有电负性气体，放电电流存在一个缓冲；热解煤气中CO2浓度越高，放电电流越小，放电越稳定，但温度越高，CO2浓度对煤气放电特性的影响越小.
Abstract: A small wire-cylinder high temperature electrostatic precipitator was used to analyze the direct current (DC) discharge characteristics of 4 types of gas (CO2/N2/air/pyrolysis gas) at 300-700℃ in order to improve the reliability and stability of the electrostatic precipitator for high temperature gas. With the temperature increasing, the discharge current increases, the onset and breakdown voltage decrease, and breakdown voltage reduces faster. The influence of temperature on electronegative gas is stronger than non-electronegative gas. Discharging in pyrolysis gas produces C and H2O, and the discharge characteristic in pyrolysis gas is similar with N2. There is a buffer under pyrolysis gas when the power supply is lower because of the existence of electronegative gas. The CO2 concentration of pyrolysis gas is higher, the discharge current is smaller, and discharging is more stable, The higher the temperature, the effect of CO2 concentration on the gas discharge characteristic is smaller.