SU926250A1 - Method for heat insulating injection string in well - Google Patents

Description

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This invention relates to the oil & gas industry, in particular, to thermal methods of oil production.

There is a method teshloizol shi, including-. the application of the heat insulating layer on the pipes before they are lowered into the well Ci.

The disadvantages of this method are the impossibility of its application with increasing depths of wells due to layer disturbances during the descent of the columns, heat loss in the well, created immediately after the supply of coolant due to the linear elongation of the column elements and the formation of uninsulated gaps. (destruction of the coating).

The closest in technical essence to the present invention is a method comprising pumping a mixture of heat-insulating material with water into the annular space of a well and removing water from the mixture 2.

The availability of this method is aeactual in its low efficiency, so

How does thermal insulation cover a small thickness, the need for significant thermal costs for evaporating the carrier, the duration of the evaporation process, the uneven removal of the carrier fluid and the distribution of the thermal insulation material in the annular gap of the casing wall — an injection column with a high evaporation rate

10 bone carrier.

The purpose of the invention is to increase the efficiency of thermal insulation by increasing the layer of thermal insulation material.

15 in the annular space.

The goal is achieved reMt that according to the method non-swellable or even non-hygroscopic material is used as a heat insulating material.

20 is copied material, and the removal of water from the mixture is carried out by filtering out at the wellhead and pumping the mixture with gas through a rippled space into scbaninas, and also by the fact that the gas is pulsed. FIG. 1 shows a diagram of a device implementing the proposed method in FIG. 2 and 3 are filter embodiments. The method of heat-insulating pressure string in the well can be implemented in a device containing a filtration partition 1 with openings 2, mounted by internal and external, identical in pitch and length of threads on the sleeves 3 of the casing and 4 injection 5 columns. The openings 6 in the injection string are located above the valve 7 installed in the jacks of the injection string at the same depth with the packer or cement bridge 8 located above the production horizon 9. At the mouth of the casing 10, a cylinder head 1 is installed with a pressure gauge 12 and a drainage nozzle. FIG. 2 and 3, variants of the device are shown, characterized in that they are made in the form of cylindrical chambers above the wellhead. The filtration partition 1 with openings 2 in its walls is made of a cylindrical form, of detachable elements (vertical - in the embodiment of Fig. 2 and vertical and horizontal - in the embodiment of Fig. 3), which increases the filtering area. The column head 11 in the embodiments of FIG. and FIG. 3 is an external one that separates the perforated head from the atmosphere and communicates the latter with the perforated head by a drain pipe for drainage. The gaps between the perforated and framing column heads are 15-20 mm. The gap on the contact of the flange connections with the perimeter of the discharge stringer does not require additional sealing, since the smaller size of the holes in the cfeHKax of the perforated heads is fulfilled, and it performs essentially the same role. The above-drainage arrangement of the perforated element in the form of a head determines not only the possibility of pouring out the separating fluid from the well, but also the possibility of controlling the operation of the device and its prevention. The heat insulating method is carried out. in the following way. A mixture of thermal insulating material C with water through pumps (pumped through injection column 5, openings 6 above valve 7 and bridge or packer 8 located above producing formation 9 into the annular space of the well. Carrier fluid, in this case water released through the filtering valve) 1 and the discharge at the column head 11, are discharged into the measuring tanks or other containers. The method is suitable for filling the annular space of the well with thermal insulating material that does not swell in water or is not even hygroscopic. materials should include basalt fiber (hygroscopicity not more than 1%). Very consistent with this. Vermiculite criterion and other materials mentioned below. Essential for the implementation of the proposed method is the ability of the material terminated into the well to not significantly reduce the permeability Formation of a filter-, ration sediment. From this point of view, glass fiber, basalt fiber, vermiculite, asbestos, etc. are most acceptable. The pulps of these materials in the aquatic environment are unstabilized systems characterized by high unsteady filtration rates. When water is filtered out during the injection of a mixture of thermal insulating material and water, the most compact filling of the annular space with thermal insulating material, i.e. The lenses (bundles) of the aqueous medium are replaced by the height of the space, replaced by the heat insulating material itself. The final part of the process is the removal of residual water by pushing it with gas through the annular space of the well. The final stage of the method, which involves the injection of gas (air), is accompanied first by the continuation of the actual filtration of water, and then by the release of aerated water from the annular space, and finally -. tically dry gas (air). In the case of a decrease in the rate of flow and the maintenance of high pressure in the stand of the injection line, this pressure is reduced to a minimum, which takes from 0.5 to 2 minutes. This makes it possible to disturb the oriented, compact arrangement of the particles of the mixture material on the parts of the device. Pulsed gas supply due to short-term shutdown of the compressor in

Overall, it provides an increase in skorokot filtering water from the mixture.

At the end of the process of filling the annular space of the well with thermal insulation material and water separation, the special head is dismantled from the wellhead and is replaced with the standard one. To preserve the thermal distribution of the heat insulating material in the annular space. In the well, in the standard head, a prophylactic perforated overpressure is mounted on the plane of its flange (FIG. 1).

Claims (2)

1. A method of insulating the injection string in a well, including injecting a mixture of heat insulating material with water into annular spaces, into wells, and removing water from the mixture, characterized in that to increase the efficiency of heat (in insulation by increasing the layer of insulating material in the annular space, non-slug is used as the insulating material The material in water is removed, and the removal of the pile from the mixture is carried out by filtering out at the wellhead and pushing the mixture with gas through the annular space in the well. 2. The method according to pl, about the t and h and h and so that the gas is carried out pulsed. Sources of information taken into account in the examination 1. Patent of Germany No. 1965342, cl. 5 A 43/24, 1977. 2. U.S. Patent No. 3,664,424, cl. 166-ZOZ, 1972 (Prototype). P ffm HOtffemeTfe / tHov fug. f F1 / gE Fog.Z