Fuel-Specific On-Load Boiler Cleaning Solutions in Waste Incineration Plants: Challenges, Concepts, Experiences

The range of fuels fed to waste incineration plants extends from well-sorted domestic refuse through mixed waste fractions to fuel mixtures that may additionally contain various types of hazardous waste and biomass. This diversity results in a great number of fuel and ash compositions. Among these are fuels with a high calorific value as well as with a low calorific value and simple fuel ashes just as highly problematic fuel ashes. The latter can lead to increased slagging in the combustion chamber and fouling in the open passes of waste incineration plants as well as accelerated corrosion. The plant operator is consequently faced with considerable challenges associated with unscheduled boiler downtime and production losses. The paper describes how fuel specific process know-how is applied in combination with fully automated, efficient onload boiler cleaning systems to control the slagging issues. The paper describes a system which utilizes water as the cleaning medium. The system allows the targeted cleaning of waste incinerators during operation. This paper points out challenges faced by plant operators and suppliers of boiler cleaning technology caused by the heterogeneous fuel composition, and describes in well monitored case studies how these challenges can be successfully met.