NOVELTY - Cogenerating ammonia synthesis gas and liquefied natural gas, e.g. comprises washing first raw material gas through a molecular sieve using low temperature methanol and then introducing into a cold box containing liquid nitrogen for washing and cooling, refluxing second raw synthesis gas into a gas cooler to exchange heat from the second fuel gas, cooling the third raw material gas using the cooler and refluxing into the second raw material gas cooler of the first raw synthesis gas, and carrying out heat exchange of fuel gas and methane rich fraction.    USE - The method is useful for cogenerating ammonia synthesis gas and liquefied natural gas.    ADVANTAGE - The method allows simple and economical cogeneration of ammonia synthesis gas and liquefied natural gas with less energy consumption and high purity.    DETAILED DESCRIPTION - Cogenerating ammonia synthesis gas and liquefied natural gas by pressure gasification of crushed coal in a fixed bed, comprises washing first raw material gas through a molecular sieve using low temperature methanol and then introducing into a cold box containing liquid nitrogen for washing and cooling, refluxing second raw synthesis gas into a gas cooler to exchange heat from the second fuel gas, cooling the third raw material gas using the cooler and refluxing into the second raw material gas cooler of the first raw synthesis gas, carrying out heat exchange of fuel gas and methane rich fraction, introducing third raw material into a first flash tank of a gas-liquid separator, allowing separated methane into a lower part of a nitrogen washing tower, performing counter-current contact and introducing fourth raw material gas of carbon monoxide, methane, argon gas in the nitrogen washing tower and then transferring heat at normal pressure and performing impurity condensation in liquid nitrogen, dissolving the purified gas in small amount of nitrogen, incorporating a part of the second raw material gas of cooler from the medium-pressure liquid nitrogen to form second nitrogen gas, returning the second nitrogen gas into the second raw material gas cooler and refluxing into the first raw synthesis gas, fuel gas and a methane-rich fraction for heat exchange, refluxing third raw material gas of cooler into a portion of the high pressure third nitrogen to form hydrogen/nitrogen volume ratio of 3 for the first raw synthesis gas, allowing raw synthesis gas into the first raw material gas cooler to exchange heat to form the second raw synthesis gas, flowing the first raw material gas into a cooler of the second raw synthesis gas by entering the third raw synthesis gas into a high pressure nitrogen cooler and entering the third fuel gas of the cooler to high pressure nitrogen, introducing fifth raw synthesis gas in the high pressure nitrogen cooler so the cooler temperature is changed to normal temperature, washing the fourth raw synthesis gas using low temperature methanol to obtain purge gas by cold forming, comprises returning the purified gas into a cooler outlet of the fifth raw synthesis gas collecting tube and adding essence into hydrogen/nitrogen volume ratio of three synthesis gas into the ammonia synthesis process, cooling the third fuel gas by entering high pressure nitrogen into a nitrogen expander for cold energy and entering second high pressure nitrogen into the first raw material gas cooler of the second raw synthesis gas to form second high pressure nitrogen, flowing the first raw material gas of cooler from the second high pressure nitrogen by entering the third high pressure nitrogen into the second raw material gas cooler and entering the second raw material gas cooler of the first raw synthesis gas, further cooling the fuel gas and second nitrogen after forming the medium-pressure liquid nitrogen, flowing the fifth gas with high pressure nitrogen into a methane rectifying tower and a bottom of a reboiler, introducing sixth high pressure nitrogen from the first raw material gas cooler of the second raw material gas and then mixing and feeding third raw material gas, flowing the second nitrogen to the second raw material gas cooler for reheating after forming the third nitrogen, allowing the first and second nitrogen into the first raw material gas cooler for reheating and then introducing into the high pressure nitrogen cooler to form another nitrogen, performing space division of nitrogen and then reheating and then pressurizing the high pressure nitrogen cooler, entering the medium-pressure liquid nitrogen into the nitrogen washing tower and other pressure nitrogen into a top of the nitrogen washing tower through the purified air outlet, mixing methane and carbon monoxide rich liquid into the methane rectifying tower and then rectifying the gas and decompressing, introducing the rectified gas into a second flash tank of the nitrogen washing tower from the bottom fraction for gas-liquid separation, allowing the separated gas and liquid into the second raw material gas cooler to form first fuel gas and then reheating and mixing to form second fuel gas, entering the second fuel gas into the first raw material gas cooler and then reheating to form third fuel gas and then introducing into a fuel gas system, discharging the gas into the methane rectifying tower, and introducing methane-rich fraction into the second raw material gas cooler for further cooling and then introducing into the liquefied natural gas storage tank to form liquefied natural gas. An INDEPENDENT CLAIM is included for a device for cogenerating ammonia synthesis gas and liquefied natural gas.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic view of a method for cogenerating ammonia synthesis gas and liquefied natural gas (Drawing includes non-English language text).