Experimental Study On The Removal Of Arsenic In Flue Gas

At present, with the continuous development of China's economy, the demand for electricity continues to grow. Among the many forms of electricity generation, thermal power has always been the dominant position which uses fossil energy as the main fuel. The huge demand of power generation makes it become one of the biggest polluting industries in China, therefore, the problem of pollutant reduction in thermal power plant has been more and more concerned by the scholars of all countries. In this paper, a low cost, green oxidant was used for arsenic removal from the coal-fired flue gas. The method has a very important significance for removal of arsenic in coal fired power plant and the ultimate realization of a variety of pollutants removal. The main contents of the paper include:1. Designing the experimental program and screening suitable oxidant of arsenic removal. It mainly contained the proposal of the experimental plan, feasibility analysis of the scheme, the experimental reagents and apparatus prepared, and making sure the method for determination of arsenic and working conditions. In this experiment, sodium hypochlorite solution was chose as oxidant.2. Making the thorough inquiries of the influencing factors and the best reaction conditions of sodium hypochlorite solution to remove arsenic. It was shown by concern experimental results that: the oxidant sodium hypochlorite solution could react with trivalent arsenic to pentavalent arsenic in a mild condition; the concentration of sodium hypochlorite solution, reaction temperature, total flue gas flow and pH were the key factors affecting the reaction efficiency.3. Simulation of the actual working of coal-fired power plant flue gas, investigated how the concentration of O2, CO2, SO2 and NO affecting the reaction efficiency of arsenic removal by sodium hypochlorite solution. It was shown by concern experimental results that: in a certain range, with the concentration of O2 increase, the arsenic removal efficiency has a slow upward trend; with the concentration of CO2 increase, the arsenic removal efficiency has no change; with the concentration of SO2 increase, the arsenic removal efficiency decreased; with the concentration of NO2 increase, with the increasing of NO concentration, the arsenic removal efficiency increased first and then gradually.4. The detection of reaction products, exploration of reaction mechanisms and expectation of the research. It mainly contained the XRD detection and ion chromatography of the product, the preliminary analysis of the reaction mechanism and the prospects for future research.