SU1632969A1 - Foam generating compound for oil well plugging - Google Patents

Abstract

The invention relates to the oil industry and is intended for foaming compositions. The goal is to increase the effectiveness of the composition. Due to an increase in foam stability. The composition contains the following components with their ratio, wt.%: As surfactants, bottom residues of synthetic glycyrin production 60.0- 73.6; as a solid phase, copper sulphate 2.4-7.5; water the rest. The composition is prepared by simply mixing the components within it under normal conditions. The composition is used to treat bottomhole zones of injection wells. This composition has low toxicity and does not adversely affect the environment. 1 tabl y (/)

Description

The invention relates to the petroleum industry, namely foaming compositions, and can be used to kill wells with a low reservoir pressure, as well as to limit the water inflow into the well.

The purpose of the invention is to increase the effectiveness of the composition by increasing the stability of the foam.

To increase foam stability, the composition contains bottoms from the production of synthetic glycerin, copper sulphate and water.

The bottoms from the production of synthetic glycerin are a dark-colored syrupy liquid, having a pH of 6-12, of the following composition, wt.%:

Polyglycerol 45

NaClЈ15

Н20

40

Polyglycerol is a compound of the general formula H (OCH2- -CH-HNg) pON, where n 1-5, with the following distribution of the components:

05 WITH No. CO 0

with

n 1 2 3

May,% 8.0-15.0 80.0-85.0 3.0-4.0

5H20

41.5-2.0

50.5-1.0 Blue sulphate - CuSO. Foaming composition receive

by mixing the components under conventional conditions.

The individual components, vat residues from the production of synthetic glycerin and copper sulfate, do not have foaming properties. A positive effect is achieved as a result of a chemical reaction between them to form a polyglice. The concentration of ingredients in the tested solution is 73.6% for waste, for copper vitriol 5 2, four%.

The use of the composition at temperatures below 60 ° Ci is impractical, since at this temperature the foaming composition begins to break down with loss of free metallic copper.

The effect of the composition on the stability of the well bore (the corrosion rate does not exceed the effect of mineralized 10

Copper copper, which simultaneously has both a foaming agent, a foam stabilizer, and a solid phase (high molecular weight components). Foaming ability is determined by the half-life of the foam.

Example. In a graduated glass beaker (V 1000 cm3), 100 cm3 of foaming mixture is poured. Foaming mixture consists

20

When inhibitor protection is used, the reagents commonly used in a concentration of 0.2% are Ural-2, IKV-4B, and ToP.

The effect of the foaming composition on reservoir properties is as follows. Selective processing of highly permeable water-washed interlayers is provided to limit water inflow into mining

out of 100 g of bottoms, 25 wells will be produced, as well as the alignment of the injectivity profile of injection wells.

VA of synthetic glycerol with a polyglycerol concentration of 45 wt.% and 35.9 g of copper sulfate solution with a concentration of 9.2 wt.%. The solution is foamed by a propeller, which is driven by an electric motor with a rotational speed of 1,400 rpm. The duration of the foaming 5 minutes After stopping the propeller, a stopwatch is turned on to determine the release time of 50 cm3 of foaming liquid. The average rate of fluid release (cm3 / s) is equal to half the amount taken, i.e. 50 cm3 divided by time:

50

tg- cho

 where with y, is the release time of 50 cm3 of foaming liquid. The stability of the foam (S, s / cm3) is expressed by the reciprocal of the rate of release of the foaming liquid:

1- 288-g

V. PMZ

V

T

CMJ

The multiplicity of the foam is determined by the ratio of the volume initially formed; Vn foam to volume of foaming fluid

TO

- 3 ° vx

6329694

The concentration of ingredients in the tested solution is 73.6% for waste products, and 2.4% for copper vitriol.

The use of the composition at temperatures below 60 ° Ci is impractical, since at this temperature the foaming composition begins to break down with loss of free metallic copper.

The effect of the composition on the stability of the well bore (the corrosion rate does not exceed the effect of mineralized 10

When inhibitor protection is used, the reagents commonly used in a concentration of 0.2% are Ural-2, IKV-4B, and ToP.

The effect of the foaming composition on reservoir properties is as follows. Selective processing of highly permeable water-washed interlayers is provided to limit water inflow into mining

5 wells, as well as leveling pro0 5 0

five

ABOUT

five

injection capacity of injection wells.

Thus, due to the high foaming capacity of the proposed composition, it becomes possible to use it for killing wells with a low formation pressure with simultaneous processing of the bottom zone.

The results of the experiments are shown in the table.

As can be seen from the table, the effectiveness of the proposed composition is more than 13 times higher than the known composition of foam stability. The ratio ensuring the effectiveness of the composition (wt.%) Of copper sulphate and polyglycerol is in the range (2.4-7.5) :( 60.0-73.6). Any extreme proportions of the components do not provide a sufficiently effective composition, which is explained by a decrease in the concentration of the foaming complexes of copper polyglycerate in solution.

The proposed composition is characterized by ease of preparation. High stability and multiplicity of foam provide effective plugging of wells with low formation formation. In addition, the composition can be used to treat the bottom-hole zones of injection wells, since the stability of the known foam systems used to limit the water inflow and to isolate water is significantly inferior to the proposed composition.

Foaming composition has low toxicity and will not adversely affect the environment. In addition, the issue of the disposal of production wastes — bottoms from the production of synthetic glycerin is being resolved.

Claims (1)

Invention Formula Foaming composition for killing wells and limiting water flow in producing wells containing surfactant and water, characterized in that, in order to increase the effectiveness of the composition by increasing foam stability, it contains bottom residues of synthetic glycerin production as a surfactant, and copper sulphate as a solid phase in the following ratio of components, wt.%: Bottoms production synthetic glycerol Copper sulfate Water 60.0-73.6 2.4-7.5 Rest Waste from the production of synthetic glycerin with a polyglycerol content of 45% by weight Known composition, wt.%: Sulfonal 2.0, ° bentonite 3.0; PAA 0.7; CSSG 8.0; water 85.3.