SU1633094A1 - Method of producing foamed-cement plugging material - Google Patents

Abstract

The invention relates to the oil and gas industry. The goal is to increase the permeability while maintaining the strength of the cement stone. The fibrous filler is sequentially soaked for 0.5-2.0 hours in a 0.8-1.0% aqueous solution of polyacrylamide, then for 0.5-2.0 hours in a liquid iron sludge - iodine-bromine production waste and dried up to a humidity of 15%. Then the solution is prepared by mixing the filler, cement cement, water and surfactant and aerating it. Use liquid iron sludge with a density of 1600 - 1800 kg / m2. Cement stone has a permeability of 2 tab. 0.5-10-2 - 7-10 2 (L

Description

The invention relates to the oil and gas industry, in particular, to methods for the preparation of foam-cement compositions for fastening at a downhole formation zone composed of weakly cemented reservoirs.

The purpose of the invention is to increase the permeability of cement stone while maintaining its strength.

The method is carried out in the following manner.

Before introducing into the cement material, the fibrous filler is successively soaked in a 0.8-1.0% aqueous solution of PAA for 0.5-2.0 hours and in a liquid sludge - iodine-bromine production for 0.5-2 hours and dried to a moisture content of at least 15%.

Example. In a measuring cup (400 ml) pour 100 g of a 1.0% aqueous solution of polyacrylamide. The estimated amount of 1% fiber is placed in this solution and soaked for 0.5 h, then this fiber is immersed in another beaker and soaked in 100 g of liquid iron sludge. After that, the fiber is removed from the measuring cup and dried to a moisture content of at least 15%. Drying the fiber is not less than 15% moisture because below 15% the film formed on the fiber surface becomes brittle and brittle. Then, 0.5 g of sulfanol is added to the water of the gate, thoroughly mixed, and the Portland cement is dissolved. In the resulting solution is added dried to a moisture content

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NOLOKNO, TUU1IPJ1MIO

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The solution is poured into a glass with a capacity of 10 cm1 and using a mussel, aerate the solution for 30 minutes at a speed of 1200 rpm. Then the rotation is stopped, the foamed solution is poured into a container and immersed in a water bath, where the solution hardens B for 3-7 days. After that, the container is opened, squeeze foam stone. Permeability, compressive strength, etc. are determined. The multiplicity and flowability are determined after foaming of the solution.

Studies of the physicomechanical properties of the foam stone were carried out at a temperature close to the well (63 ° C).

In the proposed composition can be used surfactant type sulfanol (NP-1, NI-2, NP-ZB).

The permeability of the fiber-reinforced foam stone can be widely adjusted from 0 to

2

10-4m

Iron sludge is a waste of iodine-bromine production, which is formed during the production of bromine at the stage of reduction of bromine iron and is an amorphous mixture of dark brown salts and hydro- iron with a density of 1600-1800 kg / m-1 and pH

containing

(52%)

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ABOUT

U, j,

H20 (48%).

The eternal solution contains: Ca 2.0 g / l; C1 3.95 g / l; Br 214 mg / l; Mg + 4 9.7 mg / l.

The physical nature of the phenomena occurring during the processing of the fiber in the PAL raster and iron sludge is as follows. Upon immersion and mixing of the fibers in a PAA solution, a film is formed on the surface of the fibers, resulting from the forces of adsorption and chemisorption. An aqueous solution of PAA is acceptable in the range of 0.8-1%. Within a PAA of 0.8-1%, a uniform film thickness is formed, and the viscosity of the solution allows the film to be formed to remain before transferring it and other capacity and processing with iron sludge. In order to reduce the concentration of PAA in the solution to less than 0, I ° 1 the film is weak and quickly destroyed, for ngtsentratsii

five

0

five

0

 The 1% high viscosity of PAA (400-500 sps) does not allow processing of the fiber.

Thus, the best option is 0.8-1%.

The time of exposure in the corresponding solutions of 0.5-2 hours is also essential. In the range of 0.5-1 hours of fiber treatment in a solution of PAA and iron sludge, the permeability coefficient is in the range of 0.005-10 - 0 ,. Such a fibrous foam is suitable for restricting water flows into a well. As a result of fiber exposure in both solutions from 1 to 2 hours, the permeability is in the range of 0, 7-C) 12 m2. This range of exposure can be widely applied to mount wells operating weakly cemented reservoirs.

When processing in the range from 0.5 hours, the permeability is close to or equal to 0, and when processing in the range of 2 hours, the stone's strength tends to 0.

When immersed fibers, such as nylon, in liquid iron sludge, crosslinking of polymer film molecules occurs due to Fe + ions,

five

and due to the increased acidity of pH 0.15-0.2, a double electric layer is formed between the counterions and the free ones (not included in the double

g electric layer) by ions of the same sign, being in a liquid. Thus, the treated fibers become electrically neutral. In the process of hardening cement

Calcium hydrosilicates are formed in Q or foam cement and develop in cement paste in the form of fibrous particles, the length of which after about 1 hour of hardening is about

5 0.1 µm, and a diameter of 100-200 A. Long calcium hydrosilicate fibers create a spatial bond by which adhesion is enhanced between the hydration phases.

Calcium hydrosilicate fibers have a low surface polarity. The fiber treated in this way and introduced into the foam cement solution becomes neutral due to the equilibrium charge in the electric double layer on the surface | the fibers. During the final hardening, a durable cement-based, adjustable in a wide permeability range is formed.

0

a rock. By reducing the polarity of the injected fibers, for example, nylon, the surface tension at the interface between the fibers significantly decreases at the end of the foam solution hardening, and consequently, the permeability of the capillaries formed by the fibers increases.

Thus, using the proposed method, it is possible to obtain a foam stone with high strength, good adhesion with the production column, resistance to aggressive effects, and a particularly important physical characteristic - permeability.

bridge in a wide range of 0.005-10 - 7 ..

In tab. Figures 1 and 2 summarize the results of experimental (laboratory) studies on the method for producing a foam cement material.

Consider the process of obtaining foam cement material on a typical well in the Kotur-Tepe field.

Diameter of an operational column is 140 mm; artificial slaughter 1633 m; filter interval 1541-1597 m; reservoir pressure 11.45 MPa.

The number of repairs carried out by washing the sand plug before the attachment process 5. Oil production rate of 5.4 tons / day; water flow rate of 15.0 tons / day; fluid flow rate of 20.4 tons / day; water cut is 74%.

In the cementing unit there are two containers of 3 m3 each. In the first tank, 3 MJ of a 1% aqueous solution of PAA is prepared, in the second tank, 3 m3 of liquid iron slurry with a specific gravity of 1700 kg / m3.

The required amount of cement for the well is 5 tons. The water for closing is 3 m3. B: C 0.6. Accept 3 / fibers, to the mass of cement, for example, kapron. 150 kg of nylon fiber are immersed in the first container, soaked for 0.5 h, then the same fiber (150 kg) is immersed in iron sludge and soaked for 0.5 h. After that

Remove the fiber to the surface, dry it to 15% moisture and dispense it into a container for preparing cement slurry. 0.5% surfactant (sulfanol B) to the weight of cement, i.e. 25 kg. After thoroughly mixing the cement mortar (B: C 0,6), fiber and surfactant non-foamed

The Q solution is pumped into the aerator using another cementing unit, while at the same time compressed air or natural gas is fed from the compressor, resulting in aerator

Fibrous foam cement is formed, which is injected into tubing and compression pipes, then into the reservoir until complete saturation.

The well is left alone

From 2 days After complete tierdenium fiber foam cement well mastered in the usual way.

Using the proposed method in comparison with the prototype will allow

5 to regulate the permeability in a wide range (0.05 to 10-2 m2). The created foam stone helps to reduce stress on the skeleton of the rock formation, which leads to

increase the durability of the anchoring material in the reservoir and contribute to an increase in oil production.

Claims (1)

Invention Formula The method for producing foam cement backfill material, including mixing cement cement with water, surfactant and fibrous filler and subsequent aeration, is different in that, in order to increase the permeability of the cement stone while maintaining its strength, the fibrous filler is pre-soaked in 0.5–2.0 hours in a 0.8–1.0% solution of polyacrylamide, then for 0.5–2.0 hours in a liquid, iron sludge - iodine-bromine production waste and dried. one table 2