Performance assessment of 2×90 tph (afbc) boiler and study of hp heater

Abstract TNPL (Tamilnadu Newsprint and papers limited) unit-2 has two boilers; each boiler is 90 Tons per hour capacity. These are single drum, natural circulation water tube, under bed and over bed firing, top supported pressure parts and bed plate design atmospheric fluidized bed combustion (AFBC) boiler. Imported coal is the fuel for these boilers, for better operation, a performance assessment study of these boilers has been made, also HP (high pressure) heater is a special type of heat exchanger designed for recovering of heat from extraction steam to preheat feed water. They provide efficiency gain by increasing the initial water temperature. A study has been made how the HP heater can increase the efficiency of boilers. For HP heater motive steam from turbine extraction is used after generation of power.