SU1461868A1 - Method of securing hole-bottom area of formation - Google Patents

Abstract

The invention relates to the oil and gas industry. The goal is to increase the strength of the artificial polymer filter. The latter is created by pumping the polymer composition into the bottomhole zone. After curing, the composition is treated with a heat-generating foaming composition in a quantity that provides 30-100% of the volume of the pore filter. The composition contains the following components in their ratio, wt.%; ammonium chloride 23-25; sodium nitrite 20-30; acid 0.05-2.0; sulfonic acid 0.2-1.0; water - the rest. After the reaction time has elapsed, the well is washed to remove particles that plug the pore space from the filter zone. 1 hp ff, 1 tab. wed (/)

Description

one

The invention relates to the oil and gas industry and can be used to fasten the bottomhole zone of sand producing wells.

The aim of the invention is to increase the strength of the artificial polymer filter.

As a result of processing the artificial polymer filter with a heat-generating foaming composition (TPS), a chemical exothermic reaction of sodium nitrite with ammonium chloride in the presence of an acid catalyst occurs, providing an increase in the bottom-hole formation zone temperature from 20 to 150 ° C. Under conditions of elevated temperature in the mass of the polymeric krepitel {urea-formaldehyde, alkylresorcinol, epoxy, etc.), deeper polycondensation processes take place, additional chemical bonds arise and the strength of the polymeric artificial filter increases.

In addition, when processing the TPS artificial polymer filter, particles of clay and other clogging impurities are enveloped in foam bubbles. During the backwash process, clogging particles are removed from the filter, increasing its permeability.

The method of fastening the bottomhole zone is carried out as follows.

A polymer composition comprising, in wt.%, Is pumped into the wellbore zone along the pump-compressor pipes (tubing); shale alkylresorcinol 20-25; formaldehyde 6-10; sodium chloride 30-45; blast furnace slag 5-7; agricultural labor 10-15; water - the rest. The composition is forced through a purge fluid (clay

O5 OS

about:

but

thief, water, oil) through the perforation into the enclosed space. Under the action of reservoir temperature (20-50 ° C), the composition hardens and turns into a permeable polymer filter. Water is pumped through an artificial filter to dissolve and remove sodium chloride. Then the polymer filter is treated with a solution containing ammonium chloride, sodium nitrite, acid, surfactant and water. At the same time, the specified solution is pumped into the downhole well zone through the tubing at the rate of filling 30–100% of the pore space of the filter. The well is then left under pressure at rest for the time required to react the components of the solution with 15 others, which occurs with the evolution of heat and the formation of nitrogen gas. In the presence of a frother (surfactant), the solution foams. The reaction time of the components of the solution, depending on

ten

space (100%, example 22), the temperature reaches 143 ° C. A further increase in the volume of TPS leads only to a slight increase in temperature. Consequently, the most optimal is to fill the TPS with 30-100% of the pore volume of the filter.

The volume of the TPS solution is determined by the formula

() 2-d.m,

Rde D — external diameter of the bottom-hole zone of the polymer filter, m;

d is the outer diameter of the casing, m;

h — formation thickness, m; m - effective porosity. As a result of the research, it was established that after processing the heat with the generating solution, the compressive strength of the samples

specific conditions may be different, 20 „, v ;. .op op spo /

but at least 1 hour is 4.2-5.6 MPa, which is 20-60%

After the response time has expired, more than before the treatment. Permeability

backwash the samples is 1.5-2.2 microns, which is

with the aim of removal from the filter zone zaku-25-75% more than before processing.

25

Porosity-borne particles To determine the efficiency of processing an artificial polymer filter with a heat-generating foaming solution, laboratory studies were carried out.

The research results are shown in 30

the table.

The following examples of the invention (see table) show the use of hydrochloric acid (examples 1-24), sulfuric acid, citric and acetic acids.

Claims (2)

1. A method of attaching a bottomhole formation zone with unstable rocks, including creating a filter by pumping a polymer composition into a bottomhole zone, characterized in that, in order to increase the strength of an artificial polymer filter, after curing the polymer composition, it is treated with a heat generating foam composition in amount 40 tL / nVjri rvriV i JV l Ul at 1/1 ril CHUCHICHUH Ch. - h. ..-..- jj, f f P / (examples 25-27) to obtain TPS. For 35 V, providing a filling of 30-100 to obtain TPS, the volume of the pore space of the filter can be used, any water-soluble acid .. Try to show that the goal can be achieved with all accepted quantitative ratios of the components of TPS. The substantiation of the boundary values (30-100%) of filling the pore space of the filter with TPS solution is illustrated by examples 18-23. The table shows that when the heat-generating foaming composition is filled with less than 30% of the volume of the 5th filter space (Example 18), the temperature in the bottom-hole zone rises slightly, and when filled only in P2. A method according to claim 1, characterized in that the heat-generating foaming composition comprises ammonium chloride, sodium nitrite, acid, sulfonol and water, the components being taken in the following proportion, wt%: Ammonium chloride Sodium nitrite Acid Sulfonol Water 23-25 20-30 0.05-2.0 0.2-1.0 Rest five 0 space (100%, example 22), the temperature reaches 143 ° C. A further increase in the volume of TPS leads only to a slight increase in temperature. Consequently, the most optimal is to fill the TPS with 30-100% of the pore volume of the filter. The volume of the TPS solution is determined by the formula () 2-d.m, Rde D — external diameter of the bottom-hole zone of the polymer filter, m; d is the outer diameter of the casing, m; h — formation thickness, m; m - effective porosity. As a result of the research, it was established that after processing the heat with the generating solution, the compressive strength of the samples 0 „, v ;. .op op spo / is 4.2-5.6 MPa, which is 20-60% Invention Formula 1. A method of attaching a bottomhole formation zone with unstable rocks, including creating a filter by pumping a polymer composition into the bottomhole zone, characterized in that, in order to increase the strength of an artificial polymer filter, after the polymer composition is cured, it is treated with a heat generating foam composition I h ..-..- jj, ff P / a ve providing a fill of 30-100 volumes of the filter pore space, a ve providing a fill of 30-100 volumes of the filter pore space, 2. A method according to claim 1, characterized in that the heat-generating foaming composition comprises ammonium chloride, sodium nitrite, acid, sulfonol and water, the components being taken in the following proportion, wt%:  providing a fill of 30-100 tons of pore space filter Ammonium chloride Sodium nitrite Acid Sulfonol Water 23-25 20-30 0.05-2.0 0.2-1.0 Rest Sample without additional processing 3.5 1.2 Used sulfuric acid.  Used citric acid. Isg; is used acetic acid.