Abstract: A process and apparatus for removing flue gas cleaning residues in a combustion system. The combustion system includes a combustion chamber; a hot gas filter located downstream from the combustion chamber; and washers located downstream from the hot gas filter which employ a washing liquid. The hot gas filter includes filter elements and an inlet chamber located below the filter elements. Contaminants present in flue gas are precipitated in the washing liquid. Then, the washing liquid is neutralized, thereby enriching the washing liquid with salts. Next, the enriched washing liquid is injected into the inlet chamber, whereby the washing liquid evaporates and the salts contained in the washing liquid are deposited on the filter elements where they can later be removed and mixed with ashes from the combustion chamber.

Abstract: A process for purifying flue gases by conducting the hot gases through a dry purification stage, and then through a pebble bed evaporator containing pebbles and a liquid. The flue gases then exit the pebble bed evaporator and are washed in a wet washing step. Waste liquid containing dissolved material from the wet washing step is then used as the liquid in the pebble bed evaporator; as this liquid evaporates in the pebble bed evaporator, solid precipitate forms on the pebbles. This solid precipitate is removed from the evaporator and is stored. Vapor from the pebble bed evaporator is condensed and used in the wet washing step. The purified flue gases exiting the wet washing step pass through a filter stage and are discharged.