The Design Of 450×10~4m~3/d Scale For Natural Gas Desulfurization And Decarbonization Process Unit In Jingbian Gas Field

The natural gas of changqing gas field has the following characteristics: the CO2 content is higher,generally greater than 5%;Low content of H2 S,generally less than 0.1%;Higher CO2 / H2S(mole ratio,similarly hereinafter),the ratio of average between 90 ~ 664(each field of carbon sulfur ratio less than 10);Organic sulfur content is less;The gas low temperature(3 ~ 18 ℃),etc.Needs in the depth of removal of H2 S at the same time,a large number of removal of CO2 gas quality requirements to meet the national Ⅱ goods(H2S content in 20 mg/m3,or less CO2 content of 3% or less),decarburization alcohol amine liquid consumption,when used bubble,high energy/water consumption,while natural gas purification of feed gas and gas belongs to flammable,explosive or toxic gases,high protection grade requirements;Also lack of changqing gas field water of the area,it is necessary to develop water-saving technology research problems.In the face of difficulties and challenges,the first pioneering high carbon sulphur than gas MDEA desulfurization decarburization subject + DEA mixed solution process,optimization of forming solution selection,ratio of acid gas load,the solution,the main technique parameters,such as adopting mixed alcohol amine solution cycles required amount is only 64.4% of MDEA solution circulation device unit energy consumption(MJ / 104 m3 natural gas)about 83.31% of the MDEA solution;Relative to the activation of MDEA solution,the price in mixed amine solution is only half as much as that of the activated MDEA circulation only increased by 10%,and no patent technology barriers.And optimization of high carbon sulphur than natural gas purification process,the separation of tertiary natural gas separation technology,plus the heat source to improve raw material e.g.temperature technology,ultra low load tray selection application technology,the integrated application of alcohol amine liquid rich foam technology,corrosion resistant application technology,reduces the construction investment and operation cost;Second innovation SIL level III certification of emergency shutdown system application technology,in the wet desulfurization absorption tower,purify the air separator drainage system innovation in the use level 3 choose 2 + double truncation of ESD-SIL level III,guarantee high pressure absorption system with low pressure of high reliable isolation between regeneration system;Third innovative thermal oil heating,steam added auxiliary heating water saving technology,not only improve the level of plant automation,reducing labor intensity,water consumption and desulfurization decarburization device 4.2×104 t/a reduced from 1.08×104 t/a,greatly reduces the influence on the local water system,also reduced the emissions of sewage;Finally determine the size of the 450×104 m3 / d of decarburization desulfurization equipment selection.Using the results of the construction of the fourth and fifth jingbian-yanshuiguang pipeline gas field gas purification plant desulfurization decarburization device runs stably,purify H2 S and CO2 content in the gas meet and better than the design index,satisfies the requirement of national standard.