The Measurement Of Ammonia Escape Rate Based On TDLAS

Coal-fired power plant will produce a lot of dust, CO2 and nitrogen oxides in the production process. Currently, nitrogen oxide is one of the most content of atmospheric pollutants. In recent years, China’s power industry in rapid development, followed by a large number of emissions of nitrogen oxides. In order to control nitrogen oxide emissions, China provides power plants to install denitrification equipment, selective catalytic reduction(SCR) is the most ideal choice. This method has the advantages of stock efficient, mature technology, but also Western countries commonly used methods to control nitrogen oxides. Because of the worsening environmental pollution, China’s control of nitrogen oxides gradually increase the standard catalytic reduction also will continue to expand in the Chinese power industry promotion. In the SCR process, the quantity of the ammonia used in will affect the entire denitration. If the amount of ammonia is not enough, the denitration were not complete, resulting in SCR efficiency is too low, and we can not effectively control emissions of NOX. If the quantity of ammonia is too hight, the SCR can not use the needless ammonia and lead the ammonia get away from reaction zone, which will corrode the equipment and pollute the environment. Thus it can be seen that measurement of ammonia on line is very important. We can optimize the control by referencing the data of ammonia escape, and made the system of SCR working in high efficiency. I did the following work in the study of the ammonia gas monitoring in this paper:We confirm the core methods of our monitor system, and we adopt the technology of TDLAS as our essential theories. Compared with other measuring method, TDLAS has been using in many measure system of CEMS, The technology of TDLAS is mature and reliability. It has the advantage of high precision, reflexes quickly, little background signal and low floor level. Researched many existing ammonia monitoring equipment of many factory at home and abroad, and made the field trip to the common monitoring device. Put forward the measurement and the design mentality mode taking into account of the environment power plant after summarizing the merit and demerit of all the equipment. Designing and machining the measuring equipment, and setting up the measuring system in real earnest environment. Measurement system including electronic subsystem and mechanical subsystem, and made the feasibility verification of the measurement system. Make sure the center frequency of gas absorption line, and using the experiment to verify the reliability of the spectral line. Did a lot of test using the measuring system in real earnest environment, including standardization test, stabilization test, Steam test, and so on. Experimental results show that the measuring system has the advantage of Reliability, high accuracy, low floor level, resist disturb.