Simulation Of Explosion Venting In Wet-ESP

This topic comes from a major technological innovation project of Hebei Science andTechnology Department. Focusing on explosion venting in wet electrostatic precipitator(Wet-ESP) used for gas-steam combined cycle power plant over50MW, theoreticalanalysis and numerical simulation on explosion venting were performed, discussing thedevelopment of temperature and pressure and getting flow field condition of explosion.The vent valve setting was optimized and the reliability of Wet-ESP in extreme conditionsuch as higher pressure, higher speed and high explosion was studied based on simulation,providing reliable basis to design and installation of vent valve on Wet-ESP.Based on FLUENT software, the flow field situation of Wet-ESP in running wassimulated and feasibility of simulation was proved compared with actual experience. Thenbased on Eddy Dissipation model of pre-mixed combustible gas, simulation on blastfurnace gas (BFG) explosion was carried out. The explosion simulation explored themechanism of BFG explosion and analyzed the flame and flow filed of explosion underdifferent factors such as concentration of CO, initial pressure, equivalence ratio andignition position, identified the influence of each factors. At last, explosion ventingsimulation was performed based on vent opening model, studying some influence factorsas diameter, amount and position and getting pressure decreases development of explosionventing and proposing optimization program to vent valve installation on Wet-ESP.Temperature and pressure development was analyzed in explosion simulation,showing that equivalence ratio has lager influence, followed by concentration of CO,initial pressure and ignition position. The highest development rate of temperature reachedto1.9×10~6K/s and The highest development rate of pressure reached to9×10~5KPa/s.The result of venting simulation showed that increasing the diameter and amount of ventvalve could improve the rate of explosion venting and reduce the venting time. It took twovent valves of D=600mm as the optimization program, considering the situ recovery ofvent valves. The pressure development of explosion venting based on this programmatched the ultimate pressure of Wet-ESP.