Emulsion cement slurry on hydrocarbon base

FIELD: oil and gas industry.

SUBSTANCE: cement slurry contains 46.0-75.0 wt % of binding material and as such portlandcement of packing class G or cement mix Micro TSS BTRUO or a mix of aluminous cement GTS-40 and microcement Micro TSS BTRUO in mass ratio of 3:7, or a mix of aluminous cement GTS-40 and portlandcement PTST 50 in mass ratio of 1:4 is used; 1.0-4.0 wt % of surfactant and as such a mix of emulsifying agent MR-150 is used with calcium alkyl benzosulphonate and emulsifying agent OP-4 in mass ratio of 1:4:9; or a mix of emulsifying agent MR-150 is used with calcium alkyl benzosulphonate, water-repellent agent ABR and Neftenol VKS-N in mass ratio of 4:4:3:3; 9.0-27.0 wt % of diesel fuel; 0.0-0.5 wt % of calcium chloride; 0.0-2.0 wt % of condensed microsilica MK-85 and fresh water - the remaining share.

EFFECT: improved fluidity, reduced water loss, improved strength and durability of cement stone.

2 tbl

 

The invention relates to the oil and gas industry, in particular to repair and casing, and can be used for repair and insulation works in wells to isolate extraneous fluids and getoperation channels in cement bond behind the production column and the well casing.

Known cement slurry [1 - analogue], including, wt.%:

Portland cement grouting50,0-70,0
Diesel fuelOf 10.3 and 20.3
Amaltal0,4-1,0
WaterElse

The disadvantages of the known cement slurry is:

1. The low strength of cement stone.

2. The high rate of yield.

3. The complexity of the control setting time.

4. The high viscosity.

5. Poor quality of stone at low reservoir temperatures.

The closest to the intended technical solution is a cement slurry [2 - prototype], including, wt.%:

Portland60,0-70,0
Diz�Sal fuel 10,0-20,0
Amaltal0.1 to 1.0
The sulphonole0,06-0,15
Isobutyl alcohol0,1-0,25
Calcium chloride0,01-0,025
WaterElse

The disadvantages of the known cement slurry are:

1. The low strength of cement stone.

2. The high rate of yield.

3. The complexity of the control setting time.

These disadvantages lead to problems with the uploads of the composition into the well and reduce the effectiveness of its application.

In the claimed invention solved the problem of producing a cement slurry with a high level of technological properties: low yield, high turnover, adjustable setting time in a wide temperature range, high strength and durability of cement stone.

The result is achieved in that the composition contains cement of various grades, and complex of surface-active substances (surfactants), including: emulsifier MP, repellent ADB, neftenol VC-N, alkylbenzenesulfonate of calcium ABS, emulsifier OP-4, the ratio of the concentrations of which can be controlled�STS fluid mixing cement reverse emulsion.

The features of the invention

Features of the invention emulsion cement slurry hydrocarbon based are:

1. Binder

2. Portland cement grouting dhe 50

3. Portland cement class G

4. Cement mixture, CA BTRUE "Micro"

5. Aluminous cement HZ-40

6. A mixture of Portland cement PCT 50 and alumina cement HZ-40 in a mass ratio of 1:4

7. The mixture of alumina cement HZ-40 and microcement and has backfill, CA BTRUE "Micro" in a weight ratio of 3:7

8. Surfactants

9. Emulsifier MP

10. Repellent ADB

11. The neftenol VC-N

12. Alkylbenzenesulfonate calcium ABS-Sa

13. Emulsifier OP-4

14. Mineral salt

15. Calcium chloride

16. The condensed silica fume MK-85

17. Diesel fuel

18. Fresh water

Signs: 1, 2, 5, 8, 14, 15, 17, 18 - are common with the prototype, signs: 3, 4, 6, 7, 9-13, 16 - is a significant difference from the prototype.

Summary of the invention

Proposed cement slurry contains a binder, a surfactant, diesel fuel, fresh water and may contain calcium chloride, wherein the binder used Portland cement class G, or a cement mixture, CA BTRUE "Micro", or a mixture of alumina cement HZ-40 and microcement and has�, CA BTRUE "Micro" in a weight ratio of 3:7, or a mixture of Portland cement PCT 50 and alumina cement HZ-40 in a mass ratio of 1:4; and the surfactant is a mixture of emulsifier MP-150 with alkylbenzenesulfonate calcium and emulsifier OP-4 in a mass ratio of 1:4:9; or a mixture of emulsifier MP-150 with alkylbenzenesulfonate calcium, water repellents ADB and neftenol VC-N in a weight ratio equal to 4:4:3:3, and may further contain a condensed silica fume MK-85 with the following ratio of components, wt.%:

Binder:

Portland cement class G
or a cement mixture, CA BTRUE "Micro",
or a mixture of alumina cement HZ-40 and microcement and has
CA BTRUE "Micro" in a weight ratio of 3:7,
or a mixture of Portland cement PCT 50 and aluminous
cement HZ-40 in a mass ratio of 1:446,0-75,0

Surfactants:

The mixture of emulsifier MP-150 with alkylbenzenesulfonates
calcium and emulsifier OP-4 in mass
a ratio of 1:4:9;
or a mixture of emulsifier MP-150 with alkylbenzenesulfonates
calcium, water repellents ADB and neftenol
COP-N in a weight ratio equal to 4:4:3:31,0-4,0
Diesel fuelFrom 9.0 to 27.0
Microsilica0,0-2,0
Calcium chloride0,0-0,5
Fresh waterElse

For the preparation of cement slurry were used in the experiments the following materials and reagents:

- Grouting Portland cement PCT 50 PCT G class according to GOST 1581-96.

- Aluminous cement HZ-40 GOST 969-91.

- Cement mortar", CA BTRUE" brand "Micro" comes CJSC "X-Meco-GANGA" beyond 2458-066-54651030-2010, are a mixture of cement clinker and mineral additives, characterized by a specific surface area of not less than 900,0 m2/kg.

- Emulsifier MP mark 50 is produced CJSC "Himeko-GANG" beyond 2458-097-17197708-2005, represents a hydrocarbon solution of esters of oleic, linoleic, linolenic acids, and resin acids and triethanolamine.

- Alkylbenzenesulfonate calcium (sulphonole calcium) produced by TU 2421-011-56856807-2002, is a viscous liquid from light yellow to dark brown in color. Mass fraction of active substance 70%.

- Emulsifier OP-4 is produced according to TU 6-02-997-90, is a surfactant based on ethoxylated ALKYLPHENOLS with the degree topping-out CER equal to four.

- Neftenol VC-N is available CJSC "Himeko-GANG" beyond 2483-025-54651030-2008, is a mixture aminooctane and nonionic surfactants based on ethoxylated alkyl phenols and an aqueous solution of inorganic salts.

- Water repellent ADB stamps produced 40 CJSC "Himeko-GANG" beyond 2483-081-17197708-2003 represents a hydrocarbon solution of the condensation products of fatty acids with amines and used in the form of 20%, 40% and 80% concentration in hydrocarbon solvents.

- Diesel fuel according to GOST 52368-2005.

- Microsilica condensed unconsolidated MK-85, produced by TU 5743-048-02495332-96, is an ultrafine powder material consisting of spherical particles obtained in the process of gas purification furnaces in PR�production of silicon-containing alloys. The main component of the material is silicon dioxide amorphous modification.

- Calcium chloride (calcium chloride CaCl2is produced according to GOST 450-77.

- The water is fresh, drinkable on the 2874-82.

Lowering the amount of the binder in emulsion cement mortar reduces the strength of cement stone. Increase increase the viscosity of the cement slurry and reduce setting time.

A smaller amount of surfactant leads to reduced system stability, greater - deterioration of the mechanical properties of the stone and increase the setting time.

The decrease in the content of diesel fuel in the environment leads to an increase in the viscosity of the cement slurry, the improvement - deterioration of the mechanical properties of the stone.

Add microchimerism increases the strength of cement stone. Increase the number of microchimerism leads to an increase in the viscosity of the cement slurry and reduce setting time.

The addition of calcium chloride accelerates the setting time of cement slurry. Increase the amount of calcium chloride leads to an increase in the viscosity of the cement slurry.

The following are examples of preparation of the cement compositions in the laboratory.

In table. 1 shows the compositions according to the invention.

Example (composition No. 2 of table. 1) prepare 500 �l emulsion cement slurry hydrocarbon-based in the laboratory. In metallic glasses is 112.9 ml of diesel fuel and with stirring at 500 rpm in the paddle stirrer is added 1.4 ml of emulsifier MP 150, with 5.6 ml of alkylbenzenesulfonate of calcium, with 12.7 ml of emulsifier OP-4. Then increase the frequency to 1000 rpm and mixed for 1-3 minutes In a clean beaker with stirring was dissolved 4.7 g of calcium chloride in 169,3 ml of water. Increase the frequency up to 2000 rpm and a small stream poured salt water to diesel fuel with a surfactant and stirred for 1-2 min. Then produce a dispersion of the emulsion in the high speed mixer at 8000-12000 rpm for 5-10 min. Then in the emulsion at 1000-2000 rpm for the paddle stirrer was gradually injected 3.2 g of microcinema MK-85. Then gradually introduce 123,4 g of Portland cement PCT-50 and 493,7 g of alumina cement HZ-40. Stirred for 3-5 min at 1000-2000 rpm, the Solution is ready for laboratory testing. Compounds 1, 3, 4 from table 1 and the composition of the prototype (5) were prepared similarly.

The definition of the basic properties of cement slurries and stones was carried out in accordance with the international standard ISO 10426-2 (specification API 10A). The density of the cement slurry was determined using a beam scale for drilling mud and cement slurries FANN 140. Plastic viscosity and dynamic voltage digioptical using a rotational viscometer FANN 35SA. The water loss of the solution was determined on the tester Chandler Engineering M 7120. The thickening time of the solution was determined on the Chandler consistometer Engineering M 7222. The compressive strength of cement paste was determined on a hydraulic press PGM 500 MG-4. The results are presented in table. 2.

As can be seen from table 2, the proposed composition has a high performance: low yield, high turnover, adjustable setting time in a wide temperature range, high strength and durability of cement stone.

The list of references

1. GXM of the USSR for inventions and discoveries Copyright certificate on the invention of "Cement slurry" No. 529134 dated may 28, 1976, application No. 2160008 with priority from July 25, 1975 Authors: Mukhin, L. K., Ovalicin E. A., Shmavonian VSH, Likes M. I., Kasyanov M. N.

2. The civil code of the USSR for inventions and discoveries Copyright certificate on the invention of "Cement slurry" No. 1263817 from 15 June 1986, application No. 3829476 with priority of October 16, 1984 Authors: Mukhin L. K., Shevelev N. And., Prokhorov, O. V., Dudkina N. In.

Cement slurry contains a binder, a surfactant, diesel fuel, fresh water and may contain calcium chloride, characterized in that the binder used Portland cement class G, or semen�tion mixture, CA BTRUE "Micro", or a mixture of alumina cement HZ-40 and CA microcement and has BTRUE "Micro" in a weight ratio of 3:7, or a mixture of Portland cement PCT 50 and alumina cement HZ-40 in a mass ratio of 1:4; and the surfactant is a mixture of emulsifier MP-150 with alkylbenzenesulfonate calcium and emulsifier OP-4 in a mass ratio of 1:4:9; or a mixture of emulsifier MP-150 with alkylbenzenesulfonate calcium, water repellents ADB and neftenol VC-N in a weight ratio equal to 4:4:3:3, and may further contain a condensed silica fume MK-85 with the following ratio of components, wt.%:
Binding material:

Portland cement class G
or a cement mixture, CA BTRUE "Micro",
or a mixture of alumina cement HZ-40
microcement and has a CA of BTRUE "Micro" in mass
the ratio of 3:7,
or a mixture of Portland cement PCT 50
alumina cement HZ-40 in mass
the ratio 1:446,0-75,0

Surfactants:
The mixture of emulsifier MP-150
alkylbenzenesulfonate calcium and emulsifier
OP-4 in a mass ratio of 1:4:9;
or a mixture of emulsifier MP-150
alkylbenzenesulfonate calcium
repellent ADB and neftenol VC-N in
a weight ratio equal to 4:4:3:31,0-4,0
Diesel fuelFrom 9.0 to 27.0
Microsilica0,0-2,0
Calcium chloride0,0-0,5
Fresh waterElse



 

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