Introduction to flue gas desulfurization and denitrification monitoring and analysis technology The thermal power industry is the focus of the country’s energy conservation and emission reduction. According to the statistics of the thermal power industry by the end of 2007, the total sulfur dioxide emissions were 130,000 tons, accounting for 51% of the total national sulfur dioxide emissions; the total nitrogen oxide emissions The amount is about 8 million tons, accounting for 36% of the total nitrogen oxide emissions in the country. The sulfur dioxide and nitrogen oxide emission reduction targets proposed in the National Environmental Protection “Eleventh Five-Year Plan” have promoted the rapid development of flue gas desulfurization projects in power plants in my country, as well as the development of flue gas desulfurization online monitoring and analysis engineering technology, and the installation of power plant desulfurization projects There are nearly 10,000 sets of continuous flue gas emission monitoring systems (CEMS). The denitrification project and its monitoring and analysis have also been started, and a new technical hot spot is about to be formed. There are dozens of domestic manufacturers with CEMS manufacturing capabilities. Since the national environmental protection department has increased the monitoring of key pollution sources and the revision of flue gas emission standards, the desulfurization and monitoring analysis of power and other industries have been standardized, and the application technology of CEMS online analysis engineering has also Get rapid development. The flue gas desulfurization technology (FGD) refers to the desulfurization technology after combustion. According to the dry and wet form of the desulfurization product, it is classified into: dry, semi-dry, and wet processes, of which wet flue gas desulfurization processes are used more.

Limestone/gypsum desulfurization process is the most widely used desulfurization technology in the world. At present, 85% of domestic power plant flue gas desulfurization devices use this process. The reaction principle of the wet flue gas desulfurization process is as follows: absorption: SO2+H2O=HSO3-+H+ oxidation: HSO3-+1/2O2=SO42-+H+ crystallization: CaCO3+2H+=Ca2++H2O+CO2Ca2++SO42- +2H2O=CaSO4+2H2OFGD’s continuous flue gas emission monitoring system CEMS is mainly used for online monitoring of sulfur dioxide SO2, nitrogen oxides, NOX, oxygen and O2 and other gas components emitted by flue gas. It can be monitored by monitoring the sulfur dioxide content at the inlet and outlet of FGD FGD desulfurization efficiency, usually wet flue gas desulfurization FGD desulfurization efficiency can reach 90-95%, up to 99%. Most power plant denitrification projects use a combination of furnace denitrification (low-nitrogen combustion technology) and flue gas denitrification technology. Flue gas denitrification technology mainly refers to selective catalytic reduction (SCR).