Performance And Application Research Of Acetone Gas Removed By Absorption Combined With Chemical Oxidation

Acetone gas was one of the main volatile organic compounds from pharmaceutical industry.In this paper,the absorption purification experiment system was self-designed,the acetone gas was selected as the research object,the performance of H2O2,Fenton reagent,sodium hypochlorite combined with UV for acetone gas purification,under the different process conditions,was respectively systematically studied.Gas and liquid phase products were qualitatively analyzed by gas chromatography-mass spectrometry(GC-MS),then the reaction mechanism equation of acetone with the three oxidants was preliminarily studied.On this basis,the engineering application of pharmaceutical wastewater odor purification was studied in a pharmaceutical company in Shijiazhuang.The main results were as follows.1)For the purification system of using hydrogen peroxide as oxidant,when pH value was 3,the redox potential was 300-350 mV,the liquid-gas ratio was 5 L/m3,the gas residence time was 8.8 s,UV light was 15 W,the removal efficiency of acetone gas was up to 90%.The gas phases composition contains not only unreacted acetone but also a small amount of acetic acid intermediate.So then the reaction mechanism equation of acetone with hydrogen peroxide was preliminarily established.2)For the purification system of using Fenton reagent as oxidant,when pH value was4,the redox potential was 300-350 mV,the liquid-gas ratio was 5 L/m3,the gas residence time was 8.8 s,UV light was 15 W,the removal efficiency of acetone gas was up to 92%.The gas phases composition contains not only unreacted acetone but also a small amount of acetic acid intermediate.So then the reaction mechanism equation of acetone with Fenton reagent was preliminarily established.3)For the purification system of using sodium hypochlorite as oxidant,when pH value was 11,the redox potential was 580-620 mV,the liquid-gas ratio was 5 L/m3,the gas residence time was 9.6 s,UV light was 15 W,the removal efficiency of acetone gas was up to 95%.The gas phases composition contains not only unreacted acetone but also a small amount of chloroform intermediate.So then the reaction mechanism equation of acetone with sodium hypochlorite was preliminarily established.4)The process capacity of the demonstration project for waste gas purification system was 20 000 m3/h,the total investment of the project was 5 636 600 yuan.The acetone inletconcentration in the odor gas was 500 mg/m3,after the odor from pharmaceutical wastewater was purfied by the absorption combined with chemical oxidation process,acetone gas outlet concentration was less than 20 mg/m3,which reached the requirements of emissions control standards of volatile organic compounds for industrial enterprises(DB 13/2322-2016).The project had better environmental benefits and social benefits.