A new heat recovery and desulphurization plant for 4 wet kilns in Aalborg Portland

Aalborg Portland has developed and implemented a system for heat recovery and desulfurization of the flue gases from four white kilns. The gas volume is 430000 Nm/sup 3//h. The heat regeneration is accomplished by cooling the gases from approx. 250 degrees C (480 degrees F) to 70 degrees C (158 degrees F) and condensing approx. 30% of the water vapor in the gases. The recovered heat, up to 42 MW, corresponding to 560 Kcal/kg clinker (2.02 Mbtu (net)/st), is sold on a commercial basis to the city district heating system and is sufficient for providing heat for 20000 households in the city. The SO/sub 2/ emission is reduced by 75-80% and converted to gypsum. The condensed water and the gypsum are all utilized in the cement production.<>