Boiler chemical cleaning waste management manual. Final report

Boiler chemical cleaning waste is generated during power plant outages when the water-side of the boiler and condenser tubes are cleaned to remove built-up scale and corrosion products that reduce heat transfer efficiency. The cleaning agents are designed to remove scale and deposits; thus, the spent cleaning solutions contain dissolved and suspended metals such as iron and copper, with lesser amounts of chromium, magnesium, nickel and zinc. The alternatives for managing boiler chemical cleaning waste include strategies for minimizing the generation of the waste, pretreatment, physical/chemical treatment, ponding, evaporation in the boiler, contract disposal, and reuse in wet scrubbers. The selection of a particular management option will be influenced by the cleaning chemical used, tube metallurgy, environmental regulations, and particulars of the plant such as the facilities and equipment available for treatment and the plant physical layout. The continued evolution of air, water, and solid waste regulations will greatly influence the choices available for cleaning chemicals, vendors, and boiler cleaning waste management options. This manual presents cost information and detailed laboratory and field data on the options available for management of this waste stream.