A gasification system for the partial oxidation of a carbonaceous feedstock to at least provide a synthesis gas , the system comprising: a reactor chamber for receiving and partially oxidizing the carbonaceous feedstock ; a quench section below the reactor chamber for holding a bath of liquid coolant; and an intermediate section connecting the reactor chamber to the quench section , the intermediate section comprising: a reactor chamber floor provided with a reactor outlet opening through which the reactor chamber communicates with the quench section to conduct the synthesis gas from the reactor chamber into the bath of the quench section ; at least one coolant conduit arranged on an outer surface of the reactor chamber floor ; and a pump system communicating with a source of a liquid coolant for circulating the liquid coolant through the at least one coolant conduit , wherein at least one layer of refractory bricks arranged on and supported by the reactor chamber floor , the refractory bricks enclosing the reactor outlet opening a lower end of the reactor chamber floor comprising a cylindrical section extending downwardly from a conical section , and a horizontal section extending inwardly from a lower end of the cylindrical section , the cooling conduit enclosing at least the cylindrical section of the reactor chamber floor . a reactor chamber for receiving and partially oxidizing the carbonaceous feedstock ; a quench section below the reactor chamber for holding a bath of liquid coolant; and an intermediate section connecting the reactor chamber to the quench section , the intermediate section comprising: a reactor chamber floor provided with a reactor outlet opening through which the reactor chamber communicates with the quench section to conduct the synthesis gas from the reactor chamber into the bath of the quench section ; at least one coolant conduit arranged on an outer surface of the reactor chamber floor ; and a pump system communicating with a source of a liquid coolant for circulating the liquid coolant through the at least one coolant conduit , wherein at least one layer of refractory bricks arranged on and supported by the reactor chamber floor , the refractory bricks enclosing the reactor outlet opening a lower end of the reactor chamber floor comprising a cylindrical section extending downwardly from a conical section , and a horizontal section extending inwardly from a lower end of the cylindrical section , the cooling conduit enclosing at least the cylindrical section of the reactor chamber floor . a reactor chamber floor provided with a reactor outlet opening through which the reactor chamber communicates with the quench section to conduct the synthesis gas from the reactor chamber into the bath of the quench section ; at least one coolant conduit arranged on an outer surface of the reactor chamber floor ; and a pump system communicating with a source of a liquid coolant for circulating the liquid coolant through the at least one coolant conduit , wherein at least one layer of refractory bricks arranged on and supported by the reactor chamber floor , the refractory bricks enclosing the reactor outlet opening a lower end of the reactor chamber floor comprising a cylindrical section extending downwardly from a conical section , and a horizontal section extending inwardly from a lower end of the cylindrical section , the cooling conduit enclosing at least the cylindrical section of the reactor chamber floor . <EOS>