Natural gas is also buried in the underground closed geological structure like crude oil, and some are stored in the same layer as crude oil, and some exist separately. For natural gas stored in the same layer as crude oil, it will be mined along with the crude oil. Self-spraying method Due to the low density of natural gas, 0.75-0.8 kg/m3, the pressure of the wellbore gas column to the bottom of the well is small; the viscosity of natural gas is small, the flow resistance in the formation and pipeline is also small; and because of the large expansion coefficient, the elastic energy is also large. . Therefore, natural gas mining generally uses self-spraying. This is basically the same as the self-spraying method. However, because the gas well pressure is generally high and the natural gas is a flammable and explosive gas, the pressure bearing capacity and sealing performance of the gas production wellhead device are much higher than those for the oil production wellhead device. Natural gas extraction is also characterized. First, natural gas, like crude oil, is often a storage system with bottom or side water. With the exploitation of natural gas, the elastic energy of the water will drive the water into the gas reservoir along the high permeability zone. In this case, due to the hydrophilicity of the rock LNG installation itself and the capillary pressure, the intrusion of water does not effectively displace the gas, but closes the undischarged gas in the slot or cavity to form a dead zone. . This part is trapped in the high-pressure gas in the water intrusion zone, the amount can be as high as 30% to 50% of the pore volume of the rock, thereby greatly reducing the ultimate recovery of the gas reservoir. Secondly, after the gas production in the gas well, the seepage resistance of the gas flow into the bottom of the well will increase, and the total energy consumption of the gas-liquid two-phase along the oil well will increase significantly. With the increasing influence of water intrusion, the gas production rate of gas reservoirs decreases, the self-spraying capacity of gas wells weakens, and the output of single wells decreases rapidly until the bottom of the well is seriously accumulated and stops production. Control gas reservoirs mainly from two aspects, one is drainage, and the other is water shutoff. Water blocking is the use of mechanical jams, chemical plugging and other methods to separate the gas and water production layers or establish a water barrier in the reservoir. The small oil pipe drainage gas extraction method of the compressed natural gas decompression station is based on the principle that the smaller the diameter of the oil pipe is, the larger the gas flow velocity is, and the stronger the liquid carrying capacity is. Under the certain gas production volume, if the diameter of the oil pipe is selected reasonably, the well will not be formed. Underwater. This method is suitable for gas wells with high initial pressure, low formation pressure and low water production. Foam drainage method The foaming agent is added into the well through a tubing or a casing. The foaming agent dissolves into the bottom of the well and the water acts to form a bubble, which not only reduces the relative density of the effluent, but also removes the water produced in the formation from the ground with the airflow. . This method is suitable for gas wells with high formation pressure and relatively low water production. The plunger gas lift drainage method is to insert a plunger into the oil pipe. The flow path in the plunger is opened when running down, and the plunger moves downward under its own weight. When the bottom of the tubing is reached, the flow path in the plunger is automatically closed. Since the pressure acting on the bottom of the plunger is greater than the pressure acting on the top of the plunger, the plunger begins to move upward and drains the water above the plunger to the ground. When it reaches the top of the tubing, the flow path in the plunger is automatically opened and turned to the downward movement. By reciprocating the plunger, the effusion can be continuously discharged. This method is suitable for gas wells with sufficient formation pressure and large water production. Deep well pump drainage and gas extraction method The deep well pump, the sucker rod and the ground pumping unit that are driven into the well are used to control the bottom hole pressure by means of oil pipe pumping and casing gas production. This method is suitable for gas wells with low formation pressure, especially in the middle and late stages of production water wells, but the operating cost is relatively high. Gear Drive Motor,Gear Motor,Gear Motors For Driver,Fan Gear Motors GRH , https://www.grhcn.net