Development of auto combustion control logics for coal fired fluidized bed boiler on DCS: An experimental study

Abstract

An auto combustion control logics for coal fired fluidized bed boiler on distributed control system (DCS) is developed. DCS has achieved global acceptance and are essential for the successful operation of any plant. DCS is used for controlling process variables which include combustion control in coal fired FBB because of its fast response, good controllability and its capacity capability to handle complex problems. The control logic includes the combination of analog and sequential control. For minimum and maximum heat output value, the airflow value required is fixed and the same is taken form the curve. The airflow controller accepts signals from the airflow transmitter, which acts as a process value and a heat output value as set point. The control logic has been developed to control the speed of the fuel feeder in response to variations in temperature and pressure conditions. The combustion control logics have also prevented frequent shutdowns of the boiler.