Modeling and control of temperature fluctuations in the combustion chamber and boiler feed units of an incineration plant

The study on the modelling and control of temperature fluctuations in the combustion chamber (CC) and boiler feed (BF) units of the incineration plant for municipal solid wastes (MSW) management in Kano Metropolis has been achieved. The investigation of different types of solid waste streams in the metropolis was conducted and compositional analysis of the combustible MSW was carried out after incineration of the solid wastes. CC and BF units from the incineration process were modelled and temperature-controlled models developed based on the materials and energy balance principles applied at transient state. Feedback PID controller was used to stabilize the temperature fluctuations of the two units based on transfer functions of the processes and the loads developed from the resolutions of the linearized transient models. The models were simulated using Simulink embedded in MATLAB of version 4.0 with input data from the characterized combustible solid wastes and operating conditions of 5000kg/hr., 300OC and 500OC at 1atm of the CC and BF units respectively. The temperature control results revealed that manually tuned analogue valve at gains of 8, 2, 10, and 9, 4, 10 gave shortest settling time of 8.07 secs and 9.82 secs for the input temperatures of 300OC and 500OC to reached set point values stability of the CC and BF units respectively. The study recommended that the State Government should installed incinerators at the dumpsites and properly controlled them with functional PID controllers, for better management and controlling of the MSW.