Natural gas production method

Abstract

The invention discloses a natural gas production method, which comprises following steps (1) a thermal insulation oil pipe is arranged in a gas well shaft sleeve or an oil pipe, and (2) natural gas is enabled to rise to a well opening through the thermal insulation oil pipe. When the natural production method is applied to natural gas production, natural energy can by fully used to produce natural gas, temperature of the well opening of the natural gas well can be remarkably improved, the problem that hydrate can affect production of natural gas is effectively resolved, production processes that natural gas is not heated and pressurized is achieved, heating of a heating furnace and pressurization concentration transportation of a compressor can be eliminated, and production cost and energy consumption of production of natural gas can be greatly reduced. The natural gas production method has the advantages of being easy to operate, safe, reliable and the like.

Description

technical field [0001] The invention relates to the field of natural gas production, in particular to a natural gas production method. Background technique [0002] At present, the tubing method, casing method, and coiled tubing method are generally used in China to produce natural gas, which can be divided into surface choke tubing method, downhole choke tubing method, surface choke casing method, downhole choke casing method, ground Choke coiled tubing method, downhole throttle coiled tubing method. [0003] 1. Surface throttling oil pipe method: This method is to let the natural gas in the underground gas storage layer (referred to as the gas layer) rise to the well head through the oil pipe in the wellbore of the gas well, and then let the natural gas enter the gathering and transportation pipeline from the well head, and first pass through the oil pipe installed in the well. The heating furnace in the field or gas gathering station heats up the natural gas temperature,...

AI Technical Summary

Problems solved by technology

[0022] 2) Before the natural gas comes out from the wellhead and enters the buried gathering pipeline, if the natural gas is not heated, throttled and pressure-reduced at the wellsite, the natural gas will not stop after entering the gathering pipeline and fittings on the wellsite from the wellhead. The temperature of the natural gas continues to drop due to heat dissipation outward, and the temperature inside the above-ground gathering pipelines and pipe fittings may have been lower than the critical temperature of natural gas hydrate formation, resulting in the formation of hydrates that block the above-ground gathering and transportation pipelines and pipe fittings, resulting in the failure of normal production of gas wells

[0027] 3) When the natural gas leaves the surface pipeline at the well site, enters the buried gathering and transportation pipeline, and enters the heating furnace of the gas gathering station, if the natural gas is not heated, throttled and lowered, the natural gas will It will continue to dissipate heat to the ground through underground gathering and transportation pipelines and pipe fittings, and the temperature of natural gas will continue to drop, which may make the temperature of natural gas in the gathering and transportation pipeline lower than the critical temperature of hydrate formation, thereby forming hydrates to block the gathering and transportation pipeline, resulting in the failure of normal production of gas wells

[0033] According to the calculations of the known knowledge in the field, it can be known that the temperature of the natural gas gathered and transported by the gas field gathering pipeline in winter is lower than the critical temperature of hydrate formation before entering the gas gathering station, and the temperature of some gathering pipelines entering the station is already lower than the freezing point of water. If methanol is not added through the wellbore or wellsite gathering and transportation pipeline, the gathering and transportation pipelines of all gas wells from the wellhead to the gas gathering station will have the problem of hydrate blockage, and some gathering and transportation pipelines will also have the problem of freezing and freezing

[0034] 4) If the natural gas coming out of the wellhead is firstly heated, throttled and depressurized at the well site, and then transported to the gas gathering station through the gathering and transportation pipeline, it is not only necessary to install a special heating furnace or other heating equipment at the well site, but also consume a large amount of natural gas or other energy sources, and it is often necessary to insulate the above-ground and underground gathering and transportation systems before entering the gas-gathering station, resulting in a substantial increase in natural gas production costs, fixed investment, and management workload

Heating requires a large amount of natural gas

[0063] 7) Although the surface throttling tubing method can be combined with the existing wellhead surface insulation method, since the existing wellhead surface insulation method cannot increase or increase the temperature of the natural gas that has reached the wellhead, the existing wellhead surface insulation method is used to protect the wellhead. Insulation of ground gathering and transportation pipelines at well sites, buried gathering and transportation pipelines, gas gathering station pipelines, etc., although it can slow down the heat dissipation and temperature drop of natural gas at the wellhead and gathering and transportation pipelines, it cannot effectively solve the The natural gas hydrate or ice blockage problem cannot solve the problem of long-term low-temperature operation of gathering and transportation pipeline fittings that inevitably exist when natural gas is not heated and throttled, and cannot solve the problem of heating energy consumption of natural gas before throttling and depressurization

However, there are many serious defects in the application of this process: first, because the block is located in a desert, it is difficult to patrol wells, and it is difficult to find and solve the problem of heating furnace flameout in time, which makes it difficult for the gas well to produce normally; Although the gas pipeline has heat tracing and insulation, a large amount of liquid water will condense and freeze to block the gas pipeline when the temperature is lower than -20°C, which will cause the gas heating furnace to go out; The wellbore part is not insulated, and the problem of hydrate blockage is still common when the temperature is lower than -20°C, which leads to the failure of normal production of the gas well, and further causes the operation failure of the heating furnace. Fourth, the heating furnace is adjacent to the gas well. When the gas well, When the gas pipeline is accidentally vented or leaked for some reason, there will be a serious safety hazard of coexistence of gas and fire; fifth, the water produce