Abstract: A synthesis gas generator with a combustion chamber and quench chamber for generating, cooling and cleaning gases, which are generated by partial oxidation in the combustion chamber of the synthesis gas generator. The combustion chamber (3) and the quench chamber (7) are separate chambers connected by a flow channel (6). Nozzle assemblies (10, 11) with nozzle heads (9, 34), which spray in a quenching medium (8), are arranged in the gas inlet area of the quench chamber (7). The quench zone within the quench chamber (7) is joined by a useful gas-quenching medium-mixing zone. A cone (20) is located at the outlet of the quench chamber. This cone is followed by a water bath (21). The useful gas leaves the synthesis gas generator after deflection by 180.degree. in the rear-side area of the cone (20) via gas outlet openings (23).