Cryogenic method for preparing LNG (liquefied natural gas) from coke oven gas

The invention relates to the technical field of LNG (liquefied natural gas) preparation, in particular to a cryogenic method for preparing LNG from coke oven gas, which comprises the following steps: a refrigerant is pressurized in an MRC mixed refrigerant compressor and then enters a liquefaction cold box for heat exchange through a circulating pipeline, and the refrigerant after heat exchange sequentially enters a denitrification tower and an inlet separator; and finally, the refrigerant enters the MRC mixed refrigerant compressor through the circulating pipeline to be pressurized again, the refrigerant is a mixed refrigerant, and the mixed refrigerant comprises the following components in percentage by weight: 12.12% of N2, 43.18% of CH4, 21.7% of C2H4, 12.5% of C3H8 and 8.6% of C5H12. By optimizing the component proportion of the mixed refrigerant, the refrigeration cost of the compressor is saved, and the operation performance of the compressor is improved. 本发明涉及LNG制备技术领域，具体涉及一种焦炉煤气制备LNG深冷方法，包括如下步骤，制冷剂在M