Energy-saving coal-based natural gas process

The invention belongs to the technical field of environment-friendly energy, and discloses an energy-saving coal-based natural gas process. The process comprises the steps of coal gasification, conversion, low-temperature methanol washing and methanation; an absorption refrigeration step is arranged between the low-temperature methanol washing step and the methanation step; and the absorption refrigeration step comprises carrying out driving refrigeration by using low-temperature afterheat generated in the methanation step and providing cooling capacity for the low-temperature methanol washing step. According to the energy-saving coal-based natural gas process disclosed by the invention, the absorption refrigeration technology is applied in the coal-based natural gas process; low-temperature afterheat generated in the methanation step is utilized in the low-temperature methanol washing step and used for replacing a part of compression-type refrigeration and circulating water; the energy utilization efficiency is increased; use of circulating water is reduced; and the production cost of coal-based natural gas is obviously reduced.