Feed gas deacidification unit The pressurized feed gas enters the deacidification unit, which uses MDEA solution to remove CO2, H2S and other acid gases in the feed gas. Natural gas enters from the lower part of the absorber and passes through the absorber from bottom to top; The fully regenerated MDEA solution (lean solution) enters from the upper part of the absorber and passes through the absorber from top to bottom. The reverse flow MDEA solution and natural gas are fully contacted in the absorber. The CO2 in the gas is absorbed and enters the liquid phase. The unabsorbed components are led out from the top of the absorber and enter the decarbonization gas cooler and separator. The gas from the decarbonization gas separator enters the feed gas drying unit, and the condensate goes to the flash tank. The content of CO2 in the treated natural gas is less than 50ppmv. The MDEA solution absorbing CO2 is called rich solution, which is sent to the flash tower, and the natural gas produced by depressurization flash is sent to the fuel system. After heat exchange between the flashed rich liquid and the solution (lean liquid) flowing out from the bottom of the regeneration tower, raise the temperature to ~ 98 ℃ to the upper part of the regeneration tower, and carry out stripping regeneration in the regeneration tower until the lean degree of the lean liquid reaches the index. The lean liquid out of the regeneration tower passes through the rich and poor liquid heat exchanger and lean liquid cooler. The lean liquid is cooled to ~ 40 ℃, pressurized by the lean liquid pump and enters from the upper part of the absorption tower. The outlet gas at the top of the regeneration tower enters the acid gas separator through the acid gas cooler, the gas from the acid gas separator is sent to the acid gas discharge system, and the condensate is sent to the flash separator after being pressurized by the recovery pump. The heat source of reboiler of regeneration tower is heated by heat transfer oil. The main process equipment of this unit are absorption tower and regeneration tower. Feed gas drying unit The unit adopts temperature swing adsorption technology for gas separation and purification. The temperature swing adsorption technology is based on the physical adsorption of gas molecules on the internal surface of adsorbent (porous solid material), and uses the characteristics that the adsorption capacity of adsorbent for gas changes with different adsorption temperature and pressure. Under the condition that adsorbent selectively adsorbs different gas components, it adsorbs some components in mixed gas at low temperature and high pressure, The non-adsorbed components flow out through the adsorber layer and desorb these adsorbed components at high temperature and low pressure for the next low temperature and high-pressure adsorption. Multiple adsorption towers can be used to achieve the purpose of continuous gas separation. The feed gas drying unit is equipped with two adsorbers for switching operation, including one for adsorption, one for cold blowing regeneration. The feed gas from the feed gas deacidification gas unit enters the top of the adsorber. After removing water through molecular sieve, it comes out of the bottom of the adsorber. After dehydration, the natural gas enters the feed gas deacidification unit. The feed gas heavy hydrocarbon removal unit uses a small amount of purified feed gas as cold blowing and regeneration medium. The regeneration gas first passes through the cooled adsorber from bottom to top, and then the regeneration gas is heated to the regeneration temperature of 180 ~ 220 ℃ through the regeneration heater, and then enters from the bottom of the adsorber to hydrolyze and adsorb the adsorbent. The regeneration gas comes out from the top of the dryer and enters the regeneration gas separator after being cooled by the regeneration cooler. After separating the liquid, it enters the inlet of the adsorption tower. After passing through the unit, the water in dry natural gas is ≤ 1ppm. The main equipment is adsorption tower, regeneration heater, regeneration gas cooler, regeneration gas separator and regeneration gas compressor.