Keys to Successful Chemical Cleaning of Recovery Boilers, 1998 Engineering Conference Proceedings

Deposits inside boiler tubes can cause inefficient operation and hazardous tube failures. Mechanical removal of deposits from boiler tubes can be time consuming, and some areas of deposit can be missed. Chemical cleaning is the most efficient boiler cleaning method, but incomplete chemical cleaning has also been reported. Some common reasons for chemical cleaning failures discussed in this paper are: samples not representative of the deposit in the boiler, layers in the deposits, poor solvent distribution in the boiler, and deviation from the planned procedure. Key steps to assure successful chemical cleaning of paper mill recovery boilers are described in this paper. They are: detailed boiler deposit analysis and solvent testing, proper procedure development, proven equipment, environmental control, mechanical preparation, trained and experienced personnel, solvent monitoring, solvent control, and properly designed temporary equipment.