SU1252479A1 - Arrangement for producing a well yielding high-paraffin oil - Google Patents

Description

The invention relates to oil production and can be used to lift high-paraffin oil, preferably with a high pour point.

The purpose of the invention is to increase the efficiency of oil heating.

The drawing shows a diagram of the proposed device for the operation of the well.

Into production casing 1, tubing 2 is lowered. At a depth with a temperature of the subsoil above the hardening temperature of the produced oil in the production casing, a separator 3 is installed.

An additional column A with an open lower end and perforation holes 5 at the wellhead and through the body of the collar is lowered into the space above the separator and with its help it is replaced with oil by the working agent 6. A thin fluid is used as the working agent. at the temperature of the surrounding rock mass, for example, aqueous pacTBi p ethylene glycol. On an additional column (inside or outside) several heaters 7 are installed. Heaters can be of various types; electrical, chemical, etc. The outer surface of the additional column in bfECTe of the heater installation is covered with insulating sleeves 8, made, for example, of polyurethane foam in a metal casing

The distance between the heaters should be less than or equal to the height of the free convection loop, and the perforations should be made under each 1.1 m above the heater and for the top heater at the wellhead.

The device works as follows.

If it is necessary to start a well producing high paraffin oil, after it is stopped, heaters 7 are put into operation. The working agent in the additional column is heated up, due to the difference in density, rises upwards. Having reached the perforation, 1x holes 5, it passes through them into the annulus, and to replace the warm working agent in the additional column comes a new portion of cold work

what agent from the annulus. Thus, the working agent is heated, heated in an additional column,

5 and, accordingly, the heating of oil in the pump-compressor pipes. When installing multiple heaters along the length of the additional column, several closed loops are formed.

10 convection.

Example. Exploit the field, whose oil contains up to 30% paraffin and freezes at 25 ° C.

15 Into the production casing, 73-mm tubing tubes are lowered to the required depth. A packer is installed at a depth of 500 mm with a subsoil temperature above the oil freezing point corresponding to 30 ° C. An additional pipe is lowered into the space above the packer (48 mm with an open bottom end and perforations at the mouth of

25 wells and the body of the column. It is used to replace the oil in the tube space with an aqueous solution of ethylene glycol (50%). The descent depth of the additional pipe is 495 m.

Based on the depth of the descent of the additional column, its diameter, oil freezing temperature and oil heating time, the total capacity of the heaters is determined, and then the height of the contour of natural (free) convection.

In this case, the total power of the heaters based on the start-up of the well after 2 hours is 108 kW, and the height of the free convection loop is m. Thus, taking into account the disturbed calculated values, the depth of the descent of the additional column, the uniform distribution of heaters over the column height and proceeding

50

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TIR of providing free convection (i.e. the distance between the heaters should not exceed the height of the free convection loop) determines that four heaters with a capacity of 30 kW, each at the following depths, must be installed on the additional column: 495, 365, 235, 105 m Heaters are lowered on an electrical cable. Perforations through the body of the column are performed under each heater. The outer surface of the additional column in the place of installation of the heaters is insulated.

312524794

Heating of the well after stopping of all four heaters. After 2 hours, simultaneous switching on of the well is started.

Editor A. Sabo

Order 4600 / 34During 548 Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Production and printing company, Uzhgorod, up.Proektna, 4

Compiled by V. Boryskina

Tehred M. Khodanich Proofreader A.Zimokosov

Claims (1)

DEVICE FOR OPERATION OF A WELL PRODUCING A HIGH-PARAFINITY OIL, comprising a heater, production string, pump and compressor pipes, a separator and an additional pipe string with an open lower end, installed parallel to the tubing, characterized in that, in order to increase the heat insulation of oil, it is equipped with bushings, the heater is made in the form of several successively installed inside an additional column of pipe heaters with a distance between it and not greater than the height of the free convection circuit, with the additional pipe string having perforations under the wellhead and under each electric heater, and the heat-insulating £ bushings are located on the outer surface of the additional pipe string at the places where the heaters are installed. SU, „, 1252479