A process for the production of power using a combination of a partial oxidation system and a power production system, the process comprising: combining a solid or liquid fuel, oxygen, and a catalyst in a POX reactor under conditions sufficient to partially oxidize the fuel and form a POX stream comprising methane; cooling the POX stream to a temperature of about 500 °C or less; separating one or more of solids, molten metals, and acid gases from the POX stream; passing the POX stream to a POX heat exchanger and withdrawing a quantity of heat from the POX stream by cooling the POX stream to a temperature of about 100 °C or less against a cooling stream and form a POX fuel gas stream comprising methane; passing the POX fuel gas stream through a separator vessel and separating at least a portion of any water present in the POX fuel gas stream; compressing the POX fuel gas stream to a pressure of about 12 MPa or greater; combusting the POX fuel gas in a PPS combustor to form a combustion product stream at a pressure of at least about 10 MPa and a temperature of at least about 800 °C; and expanding the combustion product stream across a PPS turbine to generate power and form an expanded PPS combustion product stream; wherein the POX fuel gas stream that is compressed to a pressure of about 12 MPa or greater has a methane content of about 20% or greater by volume based on the total volume of the POX fuel gas stream, wherein prior to the step of compressing the POX fuel gas stream to a pressure of about 12 MPa or greater, at least a portion of the POX fuel gas stream is passed through a methanation unit configured to convert CO and H 2 to CH 4 and H 2 O. combining a solid or liquid fuel, oxygen, and a catalyst in a POX reactor under conditions sufficient to partially oxidize the fuel and form a POX stream comprising methane; cooling the POX stream to a temperature of about 500 °C or less; separating one or more of solids, molten metals, and acid gases from the POX stream; passing the POX stream to a POX heat exchanger and withdrawing a quantity of heat from the POX stream by cooling the POX stream to a temperature of about 100 °C or less against a cooling stream and form a POX fuel gas stream comprising methane; passing the POX fuel gas stream through a separator vessel and separating at least a portion of any water present in the POX fuel gas stream; compressing the POX fuel gas stream to a pressure of about 12 MPa or greater; combusting the POX fuel gas in a PPS combustor to form a combustion product stream at a pressure of at least about 10 MPa and a temperature of at least about 800 °C; and expanding the combustion product stream across a PPS turbine to generate power and form an expanded PPS combustion product stream; wherein the POX fuel gas stream that is compressed to a pressure of about 12 MPa or greater has a methane content of about 20% or greater by volume based on the total volume of the POX fuel gas stream, wherein prior to the step of compressing the POX fuel gas stream to a pressure of about 12 MPa or greater, at least a portion of the POX fuel gas stream is passed through a methanation unit configured to convert CO and H 2 to CH 4 and H 2 O.