在填料塔洗涤器中,利用蒸汽相变原理进行了促进燃烧源超细颗粒凝结长大并高效脱除的实验研究,通过调节进口烟气含湿量及进口烟气与洗涤水的温差建立微粒凝结长大所需的过饱和水汽环境.研究了细颗粒粒径分布、进口烟气与洗涤水的温差、蒸汽添加量和液气比等对脱除效率的影响.结果表明:使烟气在填料塔内达到过饱和状态可高效脱除燃烧源超细颗粒,脱除效率随气液温差、液气比的增大而提高.在蒸汽添加量为0.08kg/m^2、气液温差为50℃时,燃煤超细颗粒脱除效率达到81%;在相同气液温差下,增大进口烟气含湿量,可显著提高超细颗粒的脱除效率.
Based on the principal of vapor phase change, an experimental study on particle size enlargement through vapor nucleation and condensation for effective removal of combustion originated ultrafine particles has been carried out in a packed column scrubber. The supersaturation vapor condition required by condensation growth of these particles was reached by changing the moisture content in inlet flue gas and the temperature difference between inlet gas and scrubbing water. The influence of different operating conditions, such as particle size distribution, temperature difference between inlet gas and scrubbing water, additive vapor mass flow rate and water-gas ratio etc. , on particle removal efficiency, has been investigated. Results show that the ultrafine particles resulting from combustion can be effectively separated in case the supersaturation state of flue gas is reached in the packed column scrubber. The particle removal efficiency rises with increasing temperature difference between inlet gas and water, as well as with rising water-gas ratio, which can reach 81% with an additive vapor flow rate of 0.08 kg/m3 at a temperature difference of 50℃, while when the temperature difference keeps constant, this value may be highly improved by increasing the humidity of the inlet flue gas.