A process for cleaning of synthesis gases

The method is used for the purification of dust-containing synthesis gases (1), resulting in reactors or shaft (2) by carbothermal and / or electro-thermal processes, and after leaving the reactor or the shaft furnace at elevated temperatures by physical separation methods (3) (of dust-like solids 4 ) liberated and are cooled by means of a downstream heat exchanger (5). To obtain a long filter life with good cleaning of the synthesis gas, it is proposed that the dust-containing synthesis gas (1) after leaving the reactor (2) and before the release of powdered solids in the presence of water vapor through a delay zone (6) to lead the difference of Gasendtemperatur (T3) of the synthesis gas after liberation from the dust-like solids and cooling the maximum gas temperature in the residence time (T2) is set to at least 400 K.