Analysis of Boiler Fouling and Boiler Cleaning Methods at the Commerce Refuse-to-Energy Facility

Waste-to-energy boiler fire-side fouling is a major operational issue for many facilities, including the Commerce Refuse-to-Energy Facility. The Commerce Refuse-to-Energy Facility is a 350 ton per day, mass burn waterwall facility that began operation in 1987. Fouling occurs throughout the convection sections with the highest differential pressure occurring across the generating bank. Flue gas differential pressures and temperatures have been tracked and analyzed at the facility for approximately ten years during various operating conditions. It has been determined that the rate of increase of the differential pressure across the generating bank is correlated with flue gas temperature and the extent of fouling. Several different cleaning methods have been used to clear the convection zone of ash deposits, including off-line hydroblasting, on-line hydroblasting, on-line explosives cleaning, sootblowers and sonic horns. Better understanding of the fouling trends and evaluation of cleaning methods has led the facility to use a combination of on-line hydroblasting and explosives cleaning and off-line hydroblasting. The facility is now able to operate one year between planned outages, compared to ten weeks during the initial operation of the facility. Additional savings have also been achieved by reducing induced draft fan load, and possibly a reduction in tube wastage.