Numerical Simulation of Combustion of Waste Textile Pyrolysis Products in a 660 MW Coal-Fired Boiler

ObjectivesThe waste textile pyrolysis products coupled with coal-fired power generation can not only increase the treatment capacity of waste textiles and reduce power production costs, but also contribute positively to carbon emission reduction in coal-fired power plants. Therefore, numerical simulation of combustion is carried out for this process route.MethodsA grid model of a coal-fired boiler is constructed, and the reaction mechanisms of pure coal combustion and pyrolysis gas combustion are coupled. On this basis, the grid independence and model rationality are validated, and the combustion numerical simulation is carried out with the three operating parameters of mass flow rate of waste textile pyrolysis products, overfire air ratio, and pyrolysis gas inlet position as independent variables.ResultsIn the three parameters have complex and significant influences on fly ash carbon content and NOx mass concentration at the furnace outlet.ConclusionsConsidering the safety, economic, and environmental performance of this process route, it is recommended to maintain the overfire air ratio at around 31% when the heat blending ratio of pyrolysis char and pyrolysis gas is lower than 10% and blended outside the furnace. As for the mass flow rate of waste textile pyrolysis products and the pyrolysis gas inlet position, appropriate values should be determined according to actual conditions and demand.