SU933962A1 - Foam-generating composition for limiting oil inflow into well - Google Patents

Description

() FOAMING FORMULATION FOR LIMITING WATER PUMP

I

The invention relates to the oil industry, namely to the preparation of foaming solutions to limit the water inflow into the well. .

Known foaming solution containing water and surfactant (surfactant) l.

The lack of foaming solution is that the foam obtained on the basis of it, has a low stability.

The closest to the proposed is a foaming solution to limit the water inflow into the well containing surfactant, calcium chloride and water 2.,

However, the foam obtained on the basis of this foaming solution is not stable enough to effectively limit the flow of water into the well.

The purpose of the invention is to increase the stabilizing ability.

This goal is achieved by the fact that the known foaming solution containing surfactant, calcium chloride and water additionally contains a hydrocarbon in the following ratio of components, wt.%:

0.75-.0

Surfactant

0.1-3.0

Calcium chloride

0.01-0.8

Hydrocarbon

Rest

Water

ten

As surfactants are used: alkyl aryl sulfonates, for example sulfonol, DS-PAC and alkyl sulfates, for example Progress, etc.

15

Petroleum, petroleum jelly, spindle oil, cyclohexane, etc. are used as hydrocarbons.

The foaming solution is prepared 2Q as follows.

First, the foaming agent and the hydrocarbon are thoroughly mixed, then calcium chloride is added and the whole mass is mixed again, adding 3 l of 5-10 water of the total amount. The remaining amount of water is added before using the solution. The purpose of each component in the surfactant composition is the main foaming agent in the foaming of the composition. These hydrocarbons, introduced into water containing a small amount of a foaming agent (up to ZO-kQ from the amount of surfactant), do not affect the stability of the foam, and those introduced in large quantities (more than 0 from the amount of surfactant) are defoaming agents. Calcium chloride introduced in a system containing a foaming agent increases the stability of the system by salting out the surfactant. But since this involves the replacement of sulfates of Na sulfates by sulfates of Ca sulfates, the stability of the foam decreases as the resulting calcium soaps give a brittle film. In general, calcium chloride practically does not increase the stability of the foam. In the complex, the PUB-hydrocarbon-calcium chloride gives a very stable foam as a result of the formation of complexes of sulfate-calcium sulfate with hydrocarbons. The proposed composition is illustrated with an example of a sulfonol blowing agent. The invention has been tested under laboratory conditions. Foam stability is determined by the time of release of 75% of the volume of the liquid after foaming it for a certain time (three minutes) and at 5000 rpm on an FM-2M flotation machine. To determine the optimal ratios of the components of the composition, experiments were carried out according to examples. and measure 1. To stabilize the foam system, the composition is used. weight: SulfonolO, 75 Spindle oil 0.01 Calcium chloride, 0.1 Water 99, U Cooking technologies consist in placing weights of surfactant (sulfonic acid), spindle oil in a glass, after careful mixing, calcium chloride is added, and then water . The composition then undergoes foaming. EXAMPLE 2. To stabilize the foam system, use the composition, wt.%: Sulfonol1.0 Spindle oil, 0.09 Calcium chloride, 0.5 Water .98, I Process preparation technology according to example t. Example 3. To stabilize the foam system, use the composition, wt.%: SulfonolA. Spindle oil, 0.8 Calcium chloride, 3 Water, 92.2 Preparation technologies of codtaBa according to example 1. In the table. 1 shows the results of experiments according to examples 1-3. Table 1 As can be seen from the table. 1, increasing the concentration of surfactant slightly increases the stability of the foam, compared with a solution containing 1 weight. Surfactant. Based on technical and economic considerations, the optimal concentration of surfactant should be considered a concentration in the amount of 1 wt.%. Similar data were obtained when using instead of spun oil, liquid paraffin, oil, cyclohexane. The results of the experiments, in comparison with CMC, are presented in table. 2

The composition of the foaming solution

Water + sulfonic acid (%) + chloride - calcium (0.5%)

Water + sulfonic acid (1%) + liquid paraffin (}%) + .S)

Water + sulfonic acid (1) + oil (0.05%) + CaClj (U)

Water + sulfonic acid (1%) + cyclohexane (0.15%) + SaSg, (P)

Water + DS-RAS (%) + spun oil (0.08%) + CaCl2. (0.3%)

Water + sulfonic acid (1%) + spun oil (0.09%) + CaCl2 (0, S%)

As can be seen from the table. 2 with the introduction of the known composition of various hydrocarbons, the stability of the resulting foam increases 2.0-3.2 times.

Foam stability is achieved due to the hardening of the adsorption layers due to the transfer of Na sulphonates to Ca sulphonates and the subsequent formation of complexes of the latter with hydrocarbons.

The technology of restricting water inflow into the well using the proposed foaming solution is as follows.

A foaming agent and a hydrocarbon are introduced into a container with a stirrer, mixed thoroughly, after which calcium chloride is introduced. In addition, the eyelid mass is stirred and 5-10% of the total amount of water is added. The remaining amount of water is injected before using the composition.

Foam injection into the reservoir is performed by a compressor through an aerator at aeration rate of 0.5 and above under reservoir conditions.

Under reservoir conditions, the stability of the foam is significantly increased due to the high pressures in the reservoir and the specificity of the reservoir structure, which will allow for a long time (up to 1.5 g) the restriction of water inflow into the wells, while using as Table 2

Foam stability, m / min

10-20

32-50 2J -3rf 19-30

27-30

With the CMC-Na stabilizer, water inflow restrictions are reached for 6–10 months.

The technical and economic effect, given per 1 ton of foaming solution in comparison with the solution stabilized by CMC, showed that, compared to CMC, the proposed composition for the foam system makes it possible to reduce the cost of raw materials by a factor of 7.

The application of the proposed foaming solution will allow for a longer time to limit the inflow into the well, from 6-10 months to 18 months.

Claims (2)

Invention Formula Foaming solution to limit water inflow into the well containing surfactant, calcium chloride and water, characterized in that, in order to increase the stabilizing ability, it additionally contains hydrocarbon in the following ratio of components, wt.%: Surfactant Calcium Chloride Hydrocarbon Water 79339628 Information sources, 2. Vasiliev V.K. and others. In the examination, no-active substances are taken into account for education, USSR author's certificate, which are used in oil and gas N143757, cl. E 21 V 33/13, 1961. mining. M., VNIIOENG, 1976, p. 23-30,