Research On Key Technologies Of Ground Engineering In Shunnan Well Area

Northwest Oilfield Branch Shunnan well area is located at the edge of Tarim Basin, which is far away from the main block of Tahe oil field. Gas reservoir in the Shunnan block has the characteristics of super deep, high temperature, high pressure and acid gas (high content of hydrogen sulfide and carbon dioxide), and this block has the characteristics of large temperature difference between day and night, large terrain fluctuation and so on. In the process of gathering moisture, because the raw gas operation pressure and temperature falling, its dew point has been declining, which precipitated the condensed water. At the same time, along with the exploitation of the gas field, gas field will produce water, so it will lead to the occurrence of the phenomenon of pipeline effusion, and the natural gas flows in a pipeline is more complex, also brings a series of problems such as corrosion and hydrate, brings many difficulties for the development of the gas reservoir and the corresponding ground engineering design and construction.In this paper, Through the investigation of acid gas reservoir gathering and processing technology, according to the objective conditions, such as the large temperature difference between day and night, and the difficulty in the construction of the ground, the technology of acid natural gas gathering and transportation and processing is studied. By analyzing the energy consumption and operation cost, By analyzing the energy consumption and operation cost of various processes and scales, the design parameters and solvent ratio were determined, the operating parameters were optimized and the model was established, the technical problems such as the calculation of hydraulic and thermal parameters, the prediction and control of fluid volume prediction and control, the prediction and control of hydrate formation are also solved. By analyzing the corrosion risk in different gathering and processing technology, and the study of corrosion test, formed a set of suitable for Shunnan acid gas gathering pipeline corrosion and control technology.Analysis shows that the use of pressure energy in the Shunnan well area is more applicable, while natural gas power generation is not applicable to the well area; The wellhead should adopt the technology of heating and throttling, the natural gas is transported by the mixed transport process, and the gas recovery radius is 5km; The layout of the station adopts the method of combining the first level station and the two stage station, the main body of the pipe network is connected by branch and serial mode, the system adopts the medium pressure gas collecting mode, and the gas hydrate is heated by the heating method; Gas Deacidification Process adopts alkanolamine method, this solution uses MDEA serotonin solution (43%MDEA+DEA4%), natural gas dehydration process adopts three glycol dehydration process, after the treatment of natural gas products can reach the national standard 1; According to the corrosion risk analysis using ECE software, the material selection should take the following measures:single well pipeline should adopt the "and sulfur carbon steel metal tube; gas station facilities set by" anti sulfur material +coating+continuous filling of corrosion inhibitor"; The acid gas line should adopt the "anti sulfur material+pigging+Inhibitor coating" potection mode; low pressure system as much as possible with non metal or plastic composite pipe; Adding corrosion inhibitor can significantly reduce the corrosion rate, it is feasible to use corrosion inhibitor to inhibit internal corrosion, but different inhibitors play a role for different materials in different conditions are different.