refuse h r and on the other hand the sludge dried according to the process specified above a dilution and spraying chamber 12 making it possible to carry out a conditioning of the fumes the heat of which is subsequently employed according to the invention in order to carry out the drying of the liquid sludge in the dryer centrifuge 16 described below a filter preferably a bag filter 14 allowing the ash to be separated from the combustion fumes a dryer centrifuge device 16 which may be of any known type the liquid sludge is delivered to device 16 and after centrifuging and drying employing the heat of the combustion gases originating from the incinerator 10 it is possible to obtain pulverulent dry sludge exhibiting a high degree of dryness this pulverulent sludge is introduced into the incinerator 10 with the household refuse as mentioned above the separation of the steam and of the dried sludge is performed in a cyclone 18 the fumes and the steam being subsequently treated in a conventional final plant 20 before being discharged through a chimney the process forming the subject of the invention makes it possible to produce compact treatment units in which the dehydration of the sludge.