Experimental Study On SO₂Removal By Bio-trickling

Because of simple operation、low operating cost and no secondary pollution,biological flue gas desulfurization （BFGD） is to be one of the best growth prospects andpotential desulfurization technical. In China BFGD process is relatively mature and canreach high desulfurization efficiency, and now how to make it industrialized is animportant topic.This topic wants to further explore the industrialization of BFGD.It research thepretreatment of microorganism and carrier and finds the new biofilm formation. Thenthe optimal processing parameter of desulfurization system was got by some contrastexperiment. At last the topic analysis and harmless handling the final product.Test results show that mutation bacteria through irradiating thiobacillusferrooxidans for90s with microwave shorter stagnant period, ahead the logarithmicperiod, improved biological activity. FeCl3solution was used as modifier. The carrierwas ceramsite. We used high temperature burning to change chemical and physicalproperties of ceramsite surface, increasing the specific surface area and surfaceroughness. Biofilm formation adopted the combination of hanging film in and out thetower to shorten time. In the end the best tower hacking membrane conditions is: wavebed temperature30℃，Speed160r/min and two time of no vaccinated training modefor hang film. The conditions of spraying cultivation mode with the tower hungmembrane is spray volume2⁴L/h、air flow0.16m³/h or so.In the test of Bio-trickling tower，the contribution of desulfurization efficiency bypure spray medium is not more than60%. By the following conditions this test can getmore than85%of the desulfurization efficiency: SO₂entrance concentration C≤3000mg/m³, air tower gas velocity U≤0.007m/s, liquid gas ratio=5¹8L/m³, water bathtemperature for32℃（test temperature T for30℃or so）. Desulfurization system by using Bio-trickling tower produces two kinds of theproduct：Jarosite deposition and cycle fluid with lots of SO₄^2-。Jarosite can be used inrecovery colonial-style ochre yellow pigment or smelting industries。Through thechemical method such as precipitation, the SO₄^2-in cycle fluid can be eliminated，andthe product can be recycled and harmless handling.