SU1573141A1 - Enlightened plugging mixture - Google Patents

Abstract

The invention relates to the drilling of wells. The goal is to reduce the density while increasing the strength of the cement stone. The mixture contains the following components in their ratio, wt.%: Cement cement - 70-90, the product of flotation of fly ash 10-30. The mixture is prepared by mixing the dry components and then mixing them with water at a water-hard ratio of 0.5-0.55. The use of the mixture improves the insulation quality of the absorbing formations. 1 tab.

Description

The invention relates to the drilling of oil and gas wells and is intended to mount them.

The aim of the invention is to reduce the density of the cement slurry while increasing the strength of the cement stone.

The grouting mixture contains cement grouting cement and facilitates the additive - the product of flotation of fly ash in the following ratio of ingredients, wt.%:

 Grouting cement 70-90

Flotation product

fly ash10-30

The product of the fly ash flotation is a waste product and is released during the non-reagent flotation of the fly ash formed as a result of burning coal, followed by

by separation in an aquatic environment of an eolotopic. The product of the fly ash flotation is an incompatible gray powder, which is a spherical formation with sizes of 20-200 microns.

Example 1. 900 g (90% by weight) of cement cement are mixed with 100 g (10% by weight) of the product of the fly ash flotation and mixed thoroughly until a homogeneous granular mixture is obtained, which is closed with 500 g of water. The cement slurry thus obtained is characterized by a water-solid ratio of 0.5. It has the following properties: p 1520 kg / m3,

 19.5

cm,

at 22 С, ЗС1Г

.

- 6 h 30 min, 6 h 50 min, l to L 8 h 05 min, Ј mzg 2.3 MPa, Ls 5.5 MPa at, C 5 h 1 h 55 min,

SP

s |

GO Ј

Сn 2 h, Ck 2 h 50 min, 6ИЕГ 4.6 MPa, from 8.9 MPa.

Example 2. 800 g (80% w / w) of cement cement with 200 g (20% w / w) of the fly ash product floated and mixed thoroughly to obtain a homogeneous granular mixture, which is sealed with 550 g of water. The grouting JQ prepared in this way is characterized by a water-solid ratio B / T 0.5. It has the following properties: f- 1340 kg / m3, R 19 cm, at 22 ° C: 3g 6 h 35 min, € n 6 h 55 min, h 20 min,) $ 6 2.2 MPa, Lc 5.0 MPa $ at 75 ° С: 1 h 55 min, „2 h, to 3 h, 6 LISG 3.5 MPa, 6СЖ 8.3 MPa.

Example 3. 700 g (70% by weight) of 20 cement cement is mixed with 300 g (30% by weight) of the floatation product and carefully mixed until a homogeneous granular mixture is obtained, which is closed with 550 g of water. 25 The cement slurry obtained in this way is characterized by a water-solid ratio B / T of 0.55. It has the following properties: p 1170 kg / m3, P 19 CMJ at 22 ° Ci 3Q 3o | r 6 h 46 min, n 7 h 15 min, to 9 h 10 min, & IG 2.0 MPa, & 3.9 MPa-, at 75 ° С: Eo, g

2 h 05 min, „2 h 10 min, C to 3 h 05 min, ly. 3.4 MPa, 6C) ((.

  MPa.

35

The compositions and properties of cement slurries and stones are shown in Table 40.

Analysis of the data obtained shows the following.

With a content of cement cement of 70-90 wt.% And the product of flotation of fly ash of 10-30 wt.% (Examples 2 of 45 and 4) the cement slurry at B / T 0.5-0.55 is characterized by a density of 1170-1520 kg / cm3 and satisfactory values of the other properties (P 19-19.5 cm, Czag 6 h 30 min - 50

6 h 45 min, „6 h 50 min 7 h 15 min, to 8 - h 05 min 9 h 10 min, 6IEG 2.0-2.3 MPa, 3.9-5.5 MPa, at 22 ° С, C9g- 1 h 55 min, 2 h 05 min, q 2 h - 2 h 10 min, Ck 2 h 50 min - 3 h 05 min, 6IEg 3.4-3.6 MPa, Lcf 5.7-8.9 MPa, at 75 ° C).

When the content of the fly ash flotation product is 5% by weight, the density of the cement material is quite high and amounts to 1640 kg / m3 (example 1). Therefore, a decrease in the content of the flotation product relative to 10% by weight does not allow achieving the goal of the invention —HHHf because the density decreases. with low efficiency.

When the content of the product of flotation of fly ash is 40 wt.% (Example 5), although the density decreases to 1040 kg / m3, a sharp decrease in strength is nevertheless observed (6 Beg. 0.8-2.1 MPa, 6cf 1.5 and 2.9 MPa, respectively, at 22 and 75 C) with a simultaneous undesirable increase in node content (B / T 0.65), which reduces the quality of well casing. Therefore, an increase in the flotation product relative to 30 wt.% Is impractical.

The use of a lightweight tampon blend improves cementing of the absorption zones.

Claims (1)

Invention Formula Lightweight grouting mixture, including cement grouting and ash facilitating additive, characterized in that, in order to reduce the density while simultaneously increasing the strength of the cement stone, it contains as ash ash the additive component of the fly ash in the following ratio of components, wt.%: Grouting cement70-90 Flotation product fly ash10-30 Editor G. Gerber Compiled by L. Bestuzhev Tehred M.Hodanich Proofreader T.Paly Order 1627 Circulation 477 VNIKLI State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 4/5, Moscow, Zh-35, Raushsk nab. 113035 Production and publishing complex Patent. Uzhgorod, st. Gagarin, 101 Subscription