Study On Thermodynamics System Optimization Of Coal-fired Power Plant With Post-combustion Carbon Capture

Coal fired power plant can effectively reduce CO2 emissions and achieve reduction targets by means of installing CO2 capture device. But studies show that the introduction of CO2 capture device will seriously affect the thermal economy of the unit. Partly because the CO2 resolution process consumes a lot of energy; on the other hand, the introduction of CO2 capture system makes thermal system more complex, resulting in parameters of the thermodynamic system deviate from optimal allocation. How to improve coal- fired- carbon capture units' thermal economy has become an urgent problem at present. In this paper, the design features of a 1000 MW ultra supercritical coal-fired unit are studied, and a further study is carried out from the perspective of integration and optimization.The carbon capture technology is based on the chemical absorption method of MEA, and the unit is used to provide as a heat source for CO2 capture system. Firstly, the constraints and limitations of the carbon capture process in the active service unit are analyzed, and the thermal economy of the unit is analyzed. Secondly, the design scheme of the system is put forward. The thermal economic calculation frame and the parameters optimization model are established. Results show that the thermal economy of the new design unit improved significantly, and the thermal efficiency is increased by 10.7%compared with the reconstruction unit. The adaptive particle swarm optimization algorithm has better convergence and stability, and the optimization results are better than other methods. It can be used to design the power plant.The solar energy is introduced into the coal- fired- carbon capture unit, and the DSG solar collector system is used to provide the energy for the CO2 capture system.Firstly, the integrated scheme of the solar collector system, CO2 capture system, and the thermodynamic system of the unit is proposed. Secondly, taking a 1000 MW coal fired power unit as an example, the thermal economy and technology economy of the units under different integration schemes are calculated. Results show that when the 8# heater is instead, and return back to the 5# heater, the unit has the best thermal economy and technical economy. This integration works best.