Abstract: A process and system for cooling a dust-laden raw or untreated gas from the gasification of a solid carbon-containing fuel in a pressurized reactor. The gas from the reactor is introduced into a quench pipe that has a cross-sectional area that is smaller than the cross-sectional area of the reactor, and to which is supplied a quenching medium for direct cooling. The gas emerging from the outlet end of the quench pipe is deflected essentially by 180.degree. and, counter to the flow of the gas in the quench pipe, is guided through a cooling section that surrounds the quench pipe and is incorporated in a water-steam circuit.

Abstract: A device for cooling a gas that forms deposits has an upright container through which the gas to be cooled flows. At least two heating surface units with at least one heating surface of a closed geometry are provided. The heating surface units are positioned within the upright container one atop the other. A cooling medium flows through the heating surface units. Each heating surface has coordinated therewith a beating device. The container has a support and an upper one of the heating surface units is supported at the support of the container. At least one array of connecting tubes for conveying the cooling medium is provided. The array of connecting tubes connects respectively a lower one of the heating surfaces units to an adjacent upper one of the heating surface units such that the cooling medium flows sequentially through the heating surface units.