TECHNOLOGY FOCUS - INSTRUMENTATION AND TESTING - Preferred Components: The system further comprises a condensate stabilizer stabilize the condensate separated from the injection separator, and a condensate storage tank to store the stabilized condensate. Hydrogen separated from the membrane is supplied into the fuel cell arranged on the LNG-FPSO or FLNG. The separated carbon monoxide is removed by supplying into an incinerator. The fuel cell includes polymer electrolyte fuel cell solid oxide fuel cell or molten carbonate fuel cell. The LNG production system comprises an amine processing unit (5) to remove the residual acidic gases by supplying hydrogen and carbon monoxide removed gas, a dehydrating unit to remove water supplied into the acidic gases removed gas, a mercury removing unit to remove mercury supplied into the water removed gas, a liquefying unit to liquefy the mercury removed gas, and a LNG storage tank to store and supply the liquefied gas. The LNG production system produces LNG from hydrogen and carbon monoxide removed gas. The boil-off gas (BOG) generated in the LNG storage tank is supplied into the fuel cell through a BOG recovery line.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The catalyst from the methanol reactor is catalyst having bimodal pore structure containing aluminosilicate and metal. The catalyst includes platinum, zinc, palladium, silver, iridium, copper, rhodium, nickel, ruthenium, cobalt, gold, molybdenum and/or their oxide. Preferred Method: The method further comprises supplying separated hydrogen into fuel cell of LNG-FPSO or FLNG and carbon monoxide into the incinerator. The step (e) comprises removing the acidic gases from hydrogen and carbon monoxide removed gas, dehydrating by removing water from the acidic gases removed gas, removing mercury from water removed gas, producing LNG by liquefying mercury removed gas, storing the liquefied gas in the LNG storage tank, and recycling BOG generated in the LNG storage tank into fuel cell of LNG-FPSO or FLNG through the BOG recovery line.