Process for cleaning and cooling partial oxidation gases containing dust-like pollutants

Claim 1

In the process of cleaning and cooling partial oxidation gases which are produced by gasification of coal dust in a Koppers-Totzek gasifier (entrained-bed gasifier) in which process the hot gases are passed to a mechanical dust separator where about 70 to 95% of the pollutants are eliminated and the gases are then washed in a wet cleaner with water in an amount not greater than is required to eliminate the residual dust; the improvement of cooling the gases leaving the dust separator in a direct cooler to a temperature of about 75°-85° C., close to the dew point thereof but only to the extent that no condensation of steam takes place, thereafter further cooling the gases in an indirect cooler to a temperature which is 5° to 10° C. above the temperature of the cooling water at its entry into the indirect cooler, and then introducing said cooled gases into the wet cleaner for further treatment therein.