NOVELTY - The exhaust gas thermal enhancer comprises a front heater (FOC) for heating gas fluid, a fuel injector (FUI) for injecting fuel and provided in upstream of the front heater, a fuel vaporizer (VAP) that is a separate structure or integrated to the fuel injector, and an oxidation catalyst (OC1, OC2) for catalyzing oxidation of methane and provided in downstream of the front heater. The exhaust gas thermal enhancer further comprises a fuel mixer that is a separate structure or integrated to the fuel injector or to the fuel vaporizer, and a purification device.    USE - The exhaust gas thermal enhancer is useful in a gas pipe for increasing temperature to start a reaction of removing methane from gas fluid in diesel engine exhaust gas or equivalent gas fluid comprising methane (claimed).    ADVANTAGE - The exhaust gas thermal enhancer technically and economically minimizes the quantity of emission of methane in the diesel engine exhaust gas or the equivalent gas fluids.    DETAILED DESCRIPTION - The exhaust gas thermal enhancer comprises a front heater (FOC) for heating gas fluid, a fuel injector (FUI) for injecting fuel and provided in upstream of the front heater, a fuel vaporizer (VAP) that is a separate structure or integrated to the fuel injector, and an oxidation catalyst (OC1, OC2) for catalyzing oxidation of methane and provided in downstream of the front heater. The exhaust gas thermal enhancer further comprises a fuel mixer that is a separate structure or integrated to the fuel injector or to the fuel vaporizer, and a purification device. The front heater is a front heating catalyst arranged to catalyze oxidation of components of added fuel and/or gas fluid. The injected fuel comprises diesel fuel, petrol or biofuel. The front heater is arranged to oxidize diesel fuel, petrol, biofuel and/or dual fuel. The gas fluid comprises exhaust gas from diesel engine or petrol engine, waste gas or methane from dual fuel engines or burning equipment. A reducer injector injects reducing compounds such as ammonia and urea to the gas fluid, and is provided downstream to the oxidation catalyst. A gas mixer is provided downstream to the reducer injector. A hydrolysis or selective catalytic reduction catalyst is provided downstream to the oxidation catalyst. The purification device is installed in the front heater for heating the gas fluid and provided upstream to the front heater. An INDEPENDENT CLAIM is included for a method for removing methane from gas fluid.    DESCRIPTION OF DRAWING(S) - The diagram shows a schematic view of an exhaust gas thermal enhancer.    Front heater (FOC)    Fuel injector (FUI)    Oxidation catalyst (OC1, OC2)    Gas pipe (PIP)    Fuel vaporizer. (VAP)