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Gas containing CO2 corrosion problems have affected the normal development of gas fields, gas fields development benefit greatly affected, with the development of deep gas, CO2 corrosion problems will become increasingly prominent. Therefore, the urgent need to study and solve the measures, so that the existing gas containing CO2 normal development, but also for future gas field development technical reserves. According to the current field ground process, through research, identify research downhole string corrosion, CO2 separation removed in order to lose after sequel management to provide technical support. By conducting laboratory experiments to determine the corrosion in gas wells under the conditions influencing factors, corrosion characteristics. Removal process is preferably carried out, for indoor experiments to study the feasibility of CO2 removal technology. In the laboratory on four kinds of gas commonly used corrosion inhibitor is preferably carried out on five kinds of anti-corrosion coating, nine kinds of steel metal evaluated, preferably suitable for underground CO2 environment, pharmaceutical, coatings and materials. Corrosion test site in the underground gas job down into three groups to test material, through tests downhole string material is preferred. In the oil and gas CO2, H2S corrosion inhibitor used in corrosive environments with many other methods can not match advantage. According to research as well as on-site wells actual situation, select the four kinds of commonly used gas-liquid two-phase corrosion inhibitor, CT2-15, CT2-17, HT-6A, HT-6B. Through the test data shows that at lower temperatures, the flow rate of the gas and the ground is not too large gas gathering pipeline can be applied epoxy coating for corrosion protection in high temperature wells, the coating is not ideal corrosion protection methods. Decarburization by a variety of methods, combining with the aromatic system in deep gas wells features 7, DEA as a solvent selected chemical absorption method. High content of CO2 gas through the gas gathering system corrosion and protection technology research, draw a suitable Daqing CO2 corrosion technology, mainly the following conclusions: 1) For CO2 corrosion, the material can be used downhole string 1Cr13 stainless steel. For high CO2 concentration, temperature, CI-gas concentration is high, the material which can be used downhole string 00Cr22Ni5Mo3N. 2) For ground gas collection system, using carbon steel corrosion inhibitor protection measures, important equipment, shaped pieces, elbows, risers, valves and other components, can be corrosion resistant material production, or carbon steel lined with stainless steel to ensure the overall protective effect. 3) application of CO2 corrosion inhibitor can solve the problems. 4) at the lower temperature, gas flow rate is not too large, you can apply epoxy coatings for corrosion protection in high temperature gas wells, is not recommended. 5) For single well outlying stations, natural gas CO2 removal process should consider the removal of a small skid-mounted equipment to reduce investment. Process for removing CO2 gas absorption method using the DEA removal, removal of a high-voltage better removal process, while reducing operating costs.
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