FIELD: technological processes; gas industry.
SUBSTANCE: invention relates to method of conversion of exhaust gases carbon dioxide into natural gas using excess energy. At that, method includes steps of: 1) voltage transformation and rectification of excessive energy are performed, which is made from renewable energy source, and which is difficult to store or connect to power networks, directed excessive energy into electrolyte solution for electrolysis of water in it to H2 and O2, and water is removed from H2; 2) industrial waste gas is cleaned for separation of CO2, and separated from it CO2 is cleaned; 3) H2 is supplied, generated at step 1), and CO2, separated at stage 2), into equipment for synthesis, including at least two reactors with stationary layer to high-temperature gas mixture with main components of CH4 and steam to obtain highly exothermic methanation reaction between H2 and CO2, wherein primary reactor with stationary layer is kept at temperature at inlet of 250-300 °C, reaction pressure of 3-4 MPa and temperature at outlet of 600-700 °C; secondary reactor with stationary layer is kept at temperature at inlet of 250-300 °C, pressure of reaction of 3-4 MPa and temperature at outlet of 350-500 °C; at that part of high-temperature gas mixture from primary reactor with stationary layer is relevied for cooling, water removal, compression and heating, and then mixed with fresh H2 and CO2, to transport gas mixture back to primary reactor with stationary layer after volume content of CO2 in it makes 6-8 %; 4) high-temperature gas generated at the stage 3) is used to carry out indirect heat exchange with process water to produce superheated steam; 5) superheated steam is obtained at step 4) is supplied into turbine for electric power generation, and electric energy is returned to step 1) for transformation of voltage and current rectification, and for electrolysis of water; and 6) gas mixture at step 4) cooled as a result of heat exchange is condensed and dried until obtaining natural gas with content of CH4 of up to standard value. Invention also relates to device.
EFFECT: present invention increases output of methane gas.
11 cl, 2 ex, 2 dwg
