Technology and device for preparation of synthetic natural gas from coke-oven gas

The invention provides a technology and a device for preparation of synthetic natural gas from coke-oven gas. The technology comprises the steps: first, coke-oven gas and recycling gas from a recycle compressor are mixed, and the temperature is adjusted to 230-250 DEG C by a temperature adjusting system; second, the mixed gas goes into a heat-insulation-type reactor in a one-stage process and a methanation reaction is carried out; third, condensation water division are carried out, the mixed gas after water removal is divided into two parts, the first part is compressed by the recycle compressor as recycling gas and is mixed with coke-oven gas as a raw material gas, the second part is directly conveyed to an inner heat exchange reactor in a two-stage process, and a methanation reaction is carried out, and high methane gas is obtained; the high methane gas is subjected to condensation water division, and synthetic natural gas is obtained. The technology is simple, Device investment is lowered, the two-stage reactor can contend against influence of component fluctuation of coke-oven gas to CO2 in the synthetic product gas effectively, and normal operation of subsequent sections is ensured.