In the process of producing electric energy, thermal power plants will produce various forms of pollutants, including dust particles, sulfur dioxide, nitrogen oxides and other harmful gases discharged from the fuel combustion process, as well as wastewater and pulverized coal ash discharged from the operation of various equipment in the power plant. At the same time, when the power plant is running, the mechanical equipment and the generator will produce noise, which will have an adverse impact on the surrounding environment and residents’ lives.
The selective catalytic reduction (SCR) technology is mainly used in the process of environmental denitrification in thermal power plants. In SCR technology, the catalyst will promote NH3 as a reducing agent to react with NO2 in the tail gas, converting it into N2, so as to achieve the purpose of denitrification.
However, there may be some problems in the operation of SCR denitration system. For example, the ammonia supply regulating gate has a direct impact on the working condition of the denitration system. In some cases, due to the imperfect denitration automatic control system, the denitration system cannot be put into normal input, resulting in NOx exceeding the standard. Therefore, the field situation needs to be carefully analyzed to promote DCS configuration optimization, so that the denitration system to maintain a high automatic input rate. At the same time, it is also necessary to propose optimization measures according to measurement and control strategies to improve the reliability of denitration system operation.
In addition, in view of the problems existing in automatic control, such as the contradiction between the PID module control object and the control target expected in actual operation, the relevant parameter setting values can be changed by using the unit shutdown opportunity: The control object under automatic control is changed from the original “denitration efficiency” to “NOx content”, so that the automatic control target value is consistent with the assessment objective concerned by the operator, on the one hand, to ensure the environmental protection requirements of power production, and on the other hand, it greatly facilitates the operation of the operator.
In general, thermal power plants should take a series of pre-control measures in environmental denitration operation, including optimizing control strategy, improving the performance of ammonia supply regulator, strengthening equipment operation management, etc., to ensure the normal operation of denitration system and meet environmental protection requirements.
Post time: Nov-09-2023