System and method for producing LNG and hydrogen product by taking coke-oven gas as raw material

The invention discloses a system and a method for producing LNG and a hydrogen product by using coke-oven gas as a raw material, and solves the technical problems that when the coke-oven gas is used for producing LNG and an hydrogen product in the prior art, the adjustment range of the product is limited, the market demand cannot be flexibly adapted, CO2 in a device cannot be balanced, and the investment of a CO conversion process is relatively high. The system comprises a coke-oven gas pretreatment unit (1), a methanation unit (2), a deep purification unit (3), a low-temperature cold box I (4), a low-temperature cold box II (9), a hydrogen purification and liquefaction unit (5), a CO conversion unit (6), a hydrogen recovery unit (7) and a methane conversion unit (8). The system has two operation modes of LNG production and hydrogen and liquid hydrogen production, the product type can be flexibly adjusted according to market requirements, and the economic benefits of the device are improved; effective compone