For research in this point an experimental stand was developed and successfully taken into operation. The stand is based on custom developed control unit that allows for rapid algorithm synthesis and implementation. Strong variations of measured quantities were observed after periodic grate sweeping disturbing automatic detection of trends and process identification. This behavior was eliminated by change in grate sweeping algorithm. Due to significant concentration of unwanted compounds in flue gas during the on/off water temperature regulation transitional states, it was decided to implement the continuous control. This method of control is smoother and significantly helps to improve level of gaseous emissions.