Highly efficient plasma technology for ignition and thermochemical preparation of high-ash fuel in various power boilers in Kazakhstan

This study investigated results of research and implementation of a new method of organizing the combustion process of high-ash coal in furnace chambers of boilers of 3 operating thermal power plants (TPPs) with the use of plasma-fuel systems (PFS) are proposed. The boilers were selected have fundamentally different schemes for organizing the combustion processes (power, method of fuel and oxidizer supply, burner device configuration, geometry and size of the furnace chambers, and type and number of PFS). Conducted a comprehensive study of the combustion processes of high-ash coals that underwent preliminary plasma treatment. Plasma fuel activation technologies address both economic issues (reduction in fuel oil consumption, fuel savings due to reduced mechanical underburning) and environmental issues (reduction of harmful dust and gas emissions such as CO, NOx, etc.), which are particularly significant when burning low-grade coal fuels. Key characteristics of the combustion process were obtained: flow aerodynamics, temperature fields, and concentrations of harmful substances (carbon and nitrogen oxides) within the furnace chamber and at its exit for three different power boilers (BKZ-420, BKZ-160, and PK-39) when burning high-ash coal that has undergone plasma activation. It has been shown that for all power boilers, plasma technologies for thermochemical preparation of fuel reduce fuel oil consumption, saving fuel by reducing mechanical combustion and reduce emissions of harmful substances: (CO, NOx, etc.), especially characteristic when burning low-grade (high-ash) coal fuels.