Process to render harbour sludge fit for disposal by de-watering, mixing with municipal waste and pellet incineration, reducing volume for final disposal

摘要

A process and assembly are employed to incinerate dried harbour sludge with other residues such as municipal refuse, wood and sewage sludge, reducing them to ash suitable for open site disposal or another purpose. Coarse solids are first removed from the harbour sludge dredgings, which are then de-watered in a high-pressure process before being mixed and loosened with organic residues. The combination of the two substances accelerates sludge drying and increases calorific value. This mixture is converted into pellets, the calorific value of which is suitable for use as a fuel in a fluid bed incinerator. The incineration process binds a number of pollutants e.g. TBT. The resulting heat is used for the generation of steam and electricity, to pre-heat combustion air, and to dry pellets. Remaining pollutants are removed by the effluent gas and ash, and are then either placed on an open disposal site, or are used for the production of concrete.