SU1571220A1 - Expanding grouting mortar - Google Patents

Abstract

The invention relates to the drilling of wells. The goal is to increase the adhesion of the cement stone to the casing while increasing the heat resistance. The cement slurry contains the following components, parts by weight: slag-sand cement 50.0-70.0

dust ash combustible shale 30,0-50,0

bentonite dry mud 0,66-1,00

ferrochrome lignosulfonate 0,25-0,40

nitrilomethylphosphonic acid 0.03-0.10

iron vitriol 0.30-0.70

water 50.0-52.0. When preparing the solution, the bentonite powder is dispersed in water. The additives are then dissolved and the dry mixture of slag-sand cement and powdered ash is closed. The introduction of ferrous sulfate allows to slow down the rate of hydration and to ensure expansion after transportation of the solution through the well. The use of the solution will improve the quality of separation of closely spaced layers. 1 tab.

Description

The invention relates to the oil and gas industry, in particular to expanding tamponazh-1 solutions, and can be used when mounting in the temperature range of 100-150 ° C.

The purpose of the invention is to increase the adhesion of the cement stone to the casing while increasing the heat resistance.

Expandable plugging solution contains shlakopeschany well cement (Spiess) expands guide additive - dust-like fly ash of combustible slates, retarding additives - atmp (NTF) and ferrochrome lignosulfonate (FHLS), and bentonite gel powder, iron sulfate and water in the following ratio components, ma.ch .:

Slag sandy

cement50.00 - 70.00

Dust ash

oil shale 30.00 - 50.00 Nitrilotrimethyl-phosphonic acid 0, 03 - 0.10 Ferrochrome lignosulfonate 0.20 - 0.40

Bentonite clay powder Iron vitriol Water

0.66 -, 00

0.30 - 0.70 50.00 - 52.00 High temperature resistance of cement stone from cement slurry in the range of 100-150 ° C is due to the qualitative composition of slag sand sand hardening with the formation of low-base calcium hydrosilicates, as well as the formation of an additional significant amount of tobermorite hydrosilicates type and silica-containing aluminiferic calcium hydrogranates in the interaction of calcium hydroxide with hydrated slate ash — with quartz and blast-furnace slag.

The high adhesion of the cement stone from the cement slurry to the casing in the range of 100-150 ° C is caused by both the composition of the hardening products and the high residual values, i.e. the expansion and self-consolidation of hardening cement slurry as a result of the use of the additive — iron sulphate — that occurs directly in the annulus of the well.

The regulating effect of ferrous sulfate on the kinetics of the expansion of the cement slurry is due to the formation on the calcium oxide particles of a slate ash film of calcium sulfate, which slows down the rate of hydration of calcium oxide. Iron (II) hydroxides, formed as a result of hydrolysis of ferrous sulfonate, clog the surface of portlandite crystals formed by the interaction of an oxide. Calcium with water, preventing their growth and helping to slow down the expansion process of the whole system.

Hot shale dust is a finely dispersed mineral residue from the combustion of oil shale, trapped from flue gases by a dedusting system. The content of unbound calcium oxide in the zone is not less than 16%, and the dispersion (residue on sieve No. 008) is not more than 30%.

The cement slurry is prepared by conventional technology by mixing a dry mixture of cement and slate ash, followed by

five

0

five

0

five

0

five

0

five

stirring in a mixer. All additives, including iron sulphate, are introduced with the mixing water. The bentonite clay powder is introduced with the mixing water, but at the same time it is dispersed within 30-40 minutes.

Example 1.B50 mac. water dissolves 0.03 wt.h. NTF, 0.2 mea.h. FHLS, 0.3 mah.h. iron sulphate and dispersed 0.66 mach. bentonite clay powder. The solution is shut 70 math. cement cement-120 and 30 May, h. dust ash combustible shale. The resulting cement slurry with a flowability of 205 mm is pre-mixed for 2 hours in a consistometer at 8 ° C and 30 MPa, then samples are formed from it. After 24 hours of hardening at 10 ° C and 30 MPa, the expansion of the stone is 7.2%, and the adhesion is 3.2 MPa.

Example 2. In 51 mach. water dissolves 0.05 wt.h. NTF, 0.3 math. FHLS, 0.5 mac. iron sulphate and dispersed 0.85 mach. bentonite. The solution of the shutter is 60 mph. cement and 40 ma.h. shale ash. The resulting solution with a flowability of 200 mm is stirred at 100 ° C and 40 MPa. At 125 ° C and 40 MPa, the expansion of the stone is 9.5%, and the adhesion is 5.0 MPa.

Example 3. 52 ma.ch. water is dissolved 0.1 wt.h. NTF, 0.4 mac. FHLS, 0.7 ma.ch. iron vitriol. and dispersed 1 wt.h. bentonite. The solution shutter 50 wt.h. cement and 50 wt.h. shale ash. The resulting solution with a flowability of 200 mm is stirred at 120 ° C and 50 MPa. At 150 ° C and 50 MPa, the expansion of the stone is 9.1%, and the adhesion is 6.3 MPa.

Example 4. In 50 parts by weight of water, 0.03 parts by weight of water are dissolved. NTF, 0, 2 ma.ch. FHLS, 0.2 wt.h. iron sulphate and dispersed 1 m as.ch. bentonite. The solution shutter 50 wt.h. cement and 50 wt.h. shale ash. The prepared cement slurry with a flow of 210 mm is stirred at 80 ° C and 30 MPa. The expansion of the stone at 100 ° C and 30 MPa is 4.3%, and the adhesion is -1.9 MPa.

I

Example 5. In 52 wt.h. water dissolved 0, .h. NTF, 0.4 mac. FHLS, 0.8 wt.h. iron sulphate

five

and dispersed May 0.66, h. bentonite Solution shutter 70 mach. cement and 30 ma.h. shale ash. The prepared cement slurry with a flow of 180 mm is stirred at 120 ° C and 50 MPa. The expansion of the stone at 150 ° C and 50 MPa is 6.3%, and the adhesion is 2.6 MPa.

The cement slurry has a high temperature range of application, and the adjustable expansion kinetics allows to obtain an increased adhesion of the cement stone to the casing and walls and, thus, reduce the amount of repair and insulation works during the period of well development and extend the turnaround time between them.

In the temperature range of 100-150 ° C, mixtures with a ratio of HPS-120 and shale ash from 70:30 to 50:50 are optimal.

The table presents data on the effect of a two-hour pre-mixing, imitating the transportation of cement slurry into the well’s ruble space, on the expansion of cement

, / bVv

stone (ji and its adhesion to the column, characterized by the magnitude of the tangential stress () when extruding the hardened cement stone from the steel cylinder. As can be seen from the table, the expansion of the stone solidified after the preliminary mixing of the solution is only 20.2-25.0; 16.6-18.9 and 11.6-12.7% of the expansion of the stone, hardened under static conditions at 100, 125 and 1 50 ° G., respectively. This low residual expansion explains the drop (on) the value of adhesion stone in case of preliminary mixing of cement slurry (solutions 1,16, 31, 6, 21, 36, 11, 26, 41).

Introduction to the composition of the cement slurry 0.3-0.4; 0.4-0.5 and 0.6 ma.ch. iron vitriol, respectively, at 100; 125 and 150 ° C maintains high values of the adhesion of the stone to the column by slowing down the rate of hydration of calcium oxide ash in, about the time of two-hour mixing (solutions 3, 4, 18, 19, 33, 34, a, 9, 23, 24, 38 , 39, .13, 14, 28, 29, 43, 44). At the same time ЈSAV in

7I720

these solutions in 2,3-2,7 rapa higher than that of similar solutions without the addition of iron sulphate.

The dosage of ferrous sulfate below optimal values does not provide high values of stone adhesion and pre-mixed solutions. Increasing the content of KuYu pigments above the optimal increase the water requirement of cementing

 solutions and accelerates the formation of structure in them due to the activation of processes of hydration of particles of the domain slag with excess amount of sulfate ions, as evidenced by the reduction in thickening time. The decrease in the solids content in the solution and the rapid process of formation, reducing expansion, thereby causing a decrease in the amount of adhesion of the stone.

The use of the invention provides high quality rasobes2525 closely spaced layers at 100-150 ° C.

Claims (1)

Invention Formula 30 Expandable cement slurry, including burning, dust-like ash of combustible shale, bentonite mud powder, setting time delay agent, water-soluble salt, and water, characterized in that, in order to improve the adhesion of the cement stone to the casing while increasing the suitability of the sediment, while increasing the moisture content of the sediment, while also increasing the adhesion of the cement stone to the casing with a simultaneous increase of sediment. contains in 40 as a living slag-sand cement, as retarders for the setting of ferrochrome lignosulphonate, and nitrilotrimethylphosphonic acid, as a water-soluble salt 45 following ratio of components, ma.ch .: Ilakopeschany cement 50.0-70.0 Dust ash 50 oil shale 30.0 - 50.0 Bentonite clay mud 0.66 - 1.00 Ferrochrome ligno-sulfonate 0.20 - 0.40 ,, Nitrilotrimethyl-phosphonic acid0, 03, - 0, 10 Iron vitriol 0.30 - 0.70 Water 50, Q - 52.0 Property t unresolved cement mortar