Plasma-Fuel Systems Utilization for Ecological and Energy Efficiency of Thermal Power Plants

Abstract

This chapter presents the results of research and application of direct-flow, vortex, and muffle plasma-fuel systems (PFS) for coal-fired boilers of thermal power plants (TPP) at Ust-Kamenogorsk, Shakhtinsk, and Almaty (TPP-2 and TPP-3) (Kazakhstan). PFS are investigated for boilers with pulverizing systems with direct injection of dust (Shakhtinsk TPP and Almaty TPP-2) and intermediate bunker (Ust-Kamenogorsk TPP and Almaty TPP-3). Also this chapter presents the results of numerical simulations of the plasma-assisted thermochemical preparation of coal for ignition and combustion in a furnace of power boiler. The calculations were performed for a low-rank bituminous coal. 1D model PLASMA-COAL was used for plasma-fuel system computation. It describes a two-phase chemically reacting flow in a plasma chamber with an internal source of heat, which can be an arc or plasma flame. The kinetic scheme describes stages of coal devolatilisation, reactions in the gas phase, and heterogeneous reactions of carbon oxidation. Data to enable a 3D numerical simulation of coal combustion in a furnace chamber were collected. The 3D numerical experiment was performed with the aid of CINAR ICE code applied to the boilers of 420 ton/h and 75 ton/h steam productivity. A comparative analysis of the coal combustion process enhanced through plasma-fuel systems and without plasma activation was carried out. As a result of the numerical experiments, the advantages of the plasma technology have been clearly demonstrated.