RU2328515C2 - Technologic mixture for removing liquid stratal fluid from condensate well with abnormally low formation pressure - Google Patents

Abstract

FIELD: oil and gas.

SUBSTANCE: technologic mixture for removing the liquid stratal fluid from condensate well with the abnormally low formation pressure (ALFP) contains, in mass percent: 30-55 of polyethylene oxide-4000, two anionic surfactants - 25-60 of sulfonate powder and 5-10 of PO-6NP, 0-15 of the powder-like synthetic detergent.

EFFECT: providing removal of liquid stratal fluid from condensate well with the abnormally low formation pressure (ALFP) the production of which contains mineralised stratal water and hydrocarbon condensate with high initial boiling temperature.

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Description

The invention relates to the field of oil, gas and condensate production, namely, to reagents for removing liquid from the bottom of gas condensate wells.

Known surfactant "Progress" for the removal of the water-condensate mixture from the well, produced according to TU 38.10719-92.

The disadvantage of this composition is that when the gas condensate content in the formation fluid is more than 20% by volume, the use of the Progress surfactant is inefficient, because when foaming the formation water (PV) - hydrocarbon condensate (UVK) system in the pipes, a stable emulsion is formed, which leads to a decrease in the efficiency of removal of the water-condensate mixture from the well. Also, the Progress surfactant enhances corrosion of the tubing suspension and downhole equipment (1) (Abramzon A.A., Bogaro V.V., Gaeva G.M. et al .; Edited by Abramzon A.A. and Gaeva G. M. - Handbook "Surfactants". L .: Chemistry, 1979, S. 277-278).

The closest in technical essence and the achieved result is a surfactant composition - polyethylene oxide - 4000 (PEG-4000), which is a reagent for the removal of water-condensate mixture from the well (2) (Patent RU 2134775, CL ЕВВ 43/22, publ. 08.20.1999) .

PEG-4000 is effective for the removal of water-condensate mixture from shallow wells (up to 1000 m) with a UVK content in the formation fluid of not more than 20% by volume.

The main disadvantage of this composition is that when it is used in wells of more than 1000 m with abnormally low reservoir pressures, the efficiency of liquid removal is reduced due to insufficient foaming (1.5-1.7).

The aim of the present invention is to increase the efficiency of removing liquid formation fluid from gas condensate wells with abnormally low formation pressures, the products of which contain mineralized formation water and hydrocarbon condensate with a high initial boiling point.

This goal is achieved in that the technological mixture for removing liquid formation fluid from gas condensate wells with abnormally low formation pressures, the products of which contain mineralized formation water and a hydrocarbon condensate with a high initial boiling point, containing a nonionic surfactant - polyethylene oxide-4000, according to the invention , additionally contains two anionic surfactants - sulfonate powder, PO-6NP and powdered synthetic detergent (CMC) with the following m ratio, wt.%:

polyethylene oxide-4000 30-55 sulfonate powder 25-60 PO-6NP 5-10 CMC 0-15

Polyethylene oxide-4000 is produced according to TU 2483-166-05757587-2000, sulfonate powder - according to TU 2481-237-05763458-98, foaming agent PO-6NP - according to TU 38-00-0 05807999-33-95 and CMC, for example, " SORTI - economy - lemon "is produced according to TU 2381-033-00336562-2000.

The authors were able to choose such a technological mixture of nonionic and anionic surfactants, which, when mixing the components in the proposed ratio, provides enhanced foaming of the condensate liquid due to the synergistic effect of the surfactant. When using this mixture, light self-separating emulsions are formed.

The proposed mixture can be used in the form of rods and in the form of an aqueous solution to remove liquid reservoir fluid from gas condensate wells.

To enter the rods into the well, standard equipment is used: lubricators, etc., and pumping units, etc. are used to enter the aqueous solution.

Foaming rods are prepared on equipment for processing thermoplastic polymers.

The number of foaming agent rods, as well as the volume of solution injected into the well, is determined for each particular well separately, and this depends on the characteristics of the well (reservoir pressure, volume of the outflowing fluid, and the content of hydrocarbon condensate in it).

The multiplicity of the foam is determined as follows. In a glass with a capacity of 1 dm ³ , the calculated amount of produced water and the test mixture are mixed and the required amount of hydrocarbon condensate is introduced. The resulting mixture was stirred on a mixer of the type "Voronezh" at 12,000 rpm for 45 seconds. At the end of mixing, the multiplicity of the foam is determined.

Compositions, wt.%:

1. polyethylene oxide-4000 25 sulfonate powder 65 PO-6NP 5 CMC 5 2. polyethylene oxide-4000 thirty sulfonate powder 60 PO-6NP 10 CMC 0 3. polyethylene oxide-4000 55 sulfonate powder 25 PO-6NP 5 CMC fifteen 4. polyethylene oxide-4000 60 sulfonate powder twenty PO-6NP 5 CMC fifteen 5. PEG-4000 prototype

The results of the determination of the multiplicity of the foam (K) of the proposed mixture in comparison with the prototype are shown in the table.

Table Place of Birth Condensate concentration in the reservoir fluid, C _uvk ,% The concentration of surfactants in the reservoir fluid, C _Pav ,% The multiplicity of the foam, to Composition number Prototype one 2 3 four 5 Nekrasovskoye gas condensate field 10 one 2,3 2,8 3.2 2.1 1.9 Anniversary GKM thirty one 2,4 2,8 3.0 2.2 2.0 Starominskoye gas condensate field thirty one 2.2 2.7 3.0 2.1 1.8 Boundary GKM twenty one 2,5 3.0 3.8 2,3 2.0

From the data obtained it is clear that the highest multiplicity of foaming are mixtures No. 2 and 3, which are optimal.

Using the proposed mixture can improve the efficiency of the removal of liquid formation fluid from gas condensate wells with abnormally low formation pressures, the products of which contain mineralized formation water and hydrocarbon condensate with a high initial boiling point, which will improve the performance of the well.

Claims (1)

Technological mixture for removing liquid formation fluid from gas condensate wells with abnormally low formation pressures, the products of which contain mineralized formation water and a hydrocarbon condensate with a high initial boiling point, containing a nonionic surfactant - surfactant - polyethylene oxide-4000, characterized in that it additionally contains two anionic surfactants - sulfonate powder, PO-6NP and powdered synthetic detergent - CMC in the following ratio of components, wt .%: polyethylene oxide-4000 30-55 sulfonate powder 25-60 PO-6NP 5-10 CMC 0-15