RU2268990C2 - Insulation hydrosealing material - Google Patents

Abstract

FIELD: oil and gas industry, particularly isolation materials adapted to case wells and to isolate formations.

SUBSTANCE: insulation material comprises spent clay drilling mud having predetermined density, polyacrylamide, gel-forming agent, namely liquid glass, and polyethylenepolyamine. The polyethylenepolyamine includes diethylenetriamine, triethylenetetramine and triethylenepentamine. Above components are taken in the following amounts (% by clay drilling mud weight): polyacrylamide - 0.05-1.00, liquid glass - 0.1-1.5 and polyethylenepolyamine - 0.01-0.2.

EFFECT: increased structural properties, increased stability and reduced filtering ability.

1 ex, 1 tbl

Description

The invention relates to the oil and gas industry, to compositions of materials for fastening wells and separation of layers.

When attaching wells and separating formations, a method of cementing wells is widely used using cement as an insulating material. (Bulatov A.I. Formation and operation of cement stone in a well. - M .: Nedra, 1990).

However, cement is short-lived, deteriorates due to aging, under the influence of temperature, mechanical stress, formation water, and other factors. It does not provide high-quality and long-term isolation of wells due to the formation of cracks in it and at its contacts for the above reasons.

The closest analogue of the invention is the composition of the insulating material - a hydraulic seal, including spent drilling fluid of a certain density, polyacrylamide, ferrochrome lignosulfonate, CMC, corrosion inhibitors and neutralizers of chemical reagents-corrects and ZhS-7. (RF patent No. 2186937, Е 21 В 33/138. Insulating material-water seal).

The disadvantage of this insulating material-gas seal is the complex composition, low structural, mechanical and insulating properties, low sedimentation stability and stability, increased filtration. These disadvantages are due to the fact that polyacrylamide is a flocculant, therefore, it precipitates a solid phase, reduces stability, sedimentation stability and insulating properties of a water seal. In addition, PAA and CMC are subject to destruction, which leads to the loss of their original properties.

The objective of the invention is to improve the structural properties, reduce filtration and increase the stability of the insulating material-gas seal.

The problem is solved in that the insulating material-water seal, including spent clay drilling mud of a certain density and polyacrylamide, additionally contains a gelling agent - water glass and polyethylene polyamine - a mixture of diethylene triamine, triethylenetetramine and tetraethylene pentamine in the following ratio of components, wt.% Of spent clay mud:

polyacrylamide 0.05-1.00 liquid glass 0.1-1.5 specified polyethylene polyamine 0.01-0.20

To obtain an insulating material, a hydraulic seal is used spent drilling mud with a density that meets the requirements of the "Safety Rules in the oil and gas industry." In this case, hydrolyzed polyacrylamide with a molecular weight of 1 · 10 ^-6 -1 · 10 · ^{7 of} various grades DK-Drill, PDA-1030, Praestol and others, liquid glass in accordance with GOST 13078-81 and polyethylene polyamine in accordance with TU 2413-357-00203447 are used -99. Polyethylene polyamine is a mixture of diethylene triamine, triethylenetetraamine and tetraethylene pentamine, and the quantitative content of each of these components in the mixture can vary from 10 to 60 wt.%. This liquid is highly soluble in water. It is used as a hardener of epoxy resins.

From the patent and scientific and technical literature, we do not know the insulating material-water seal containing the combination of the above components in the proposed quantitative ratio, which allows us to conclude about the novelty of the claimed technical solution.

The introduction of polyacrylamide and liquid glass with polyethylene polyamine into the spent clay drilling mud turns the liquid spent clay mud of a certain density into a gel with high structural and mechanical properties, with a low filtration rate. In this case, polyethylene polyamine in an alkaline medium cross-links the polyacrylamide macromolecules into a network structure, which serves as the neoplasm, and liquid glass additionally structures the spent drilling fluid in the cells of the crosslinked polymer structure. Liquid glass and polyethylene polyamine in this case are gelling agents, at the same time they reduce the corrosion activity of the solution, neutralize its active components, and increase the resistance of the polymer to degradation.

From the current level of technology, we do not know that the components that make up the sealant-seal in this combination provide the above properties, which allows us to conclude that the proposed technical solution meets the criteria of "novelty" and "inventive step".

Example. In 1 liter of spent shale drilling solution density 1050 kg / m ^3, viscosity 23 with conventional, fluid loss 8 cm ^3/30 min and SNA 1/10 dPa equal to 5/8, is introduced under stirring 10.5 g (1%) of powdered PAA, 15.75 g (1.5%) of water glass and 2.1 g (0.2%) of polyethylene polyamine (PEPA).

After mixing, the composition is kept for 3 hours in anticipation of gelation. After gelation, the properties of the insulating material are determined.

The table shows the compositions and properties of the insulating material-water seal. From the data of the table it follows that the viscosity, static shear stress and stability are higher, and water loss is lower than that of the compositions of the prototype.

Higher viscosity and strength of the structure, stability and low water loss of the developed material will provide more effective isolation of the layers, the long-term action of the water seal. To increase the density, mineral fillers can be introduced into the composition of the insulating material - clay, chalk, barite, etc.

Insulation material-water seal during the construction of wells is prepared in containers. To do this, in the estimated required amount of spent clay drilling mud, with stirring, polyacrylamide, water glass, and polyethylene polyamine are dissolved in a predetermined ratio. If it is necessary to increase the density, mineral fillers - clay, chalk, barite - are introduced into the composition of the hydraulic seal. Then the insulating material is pumped into the well. Prior to gelation for 3 hours, this water trap retains sufficient fluidity for pumping. In the well, this insulating material passes from a liquid state into a gel state, acquires high structural-mechanical, insulating properties.

Table Structure The content of components,% Solution properties Stability% Clay mud Polyacrylamide Liquid glass Polyethylene polyamine Density, g / cm ³ Conditional viscosity, s Indicator filtration, cm ^3/30 min Static shear stress, dPa 1 min 10 min Source one hundred - - - 1.05 23 8 5 8 0.3 one one hundred 0.05 0.1 0.01 1.05 25 7 10 fifteen 0.2 2 one hundred 0.1 0.2 0.05 1.05 35 5 28 33 0 3 one hundred 0.3 0.5 0.1 1.06 180 four 110 141 0 four one hundred 0.5 1,0 0.5 1.06 n / t 3 162 124 0 5 one hundred 1,0 1,5 1,0 1,07 n / t 2 298 322 0 Prototype one hundred 0.01 - - 1.05 23 8 6 8 3 Prototype one hundred 1,0 - - 1.06 n / t 5 156 202 2 n / t - does not flow

Claims (1)

A water trap insulation material, including spent clay drilling mud of a certain density and polyacrylamide, characterized in that it additionally contains a gelling agent - water glass and polyethylene polyamine - a mixture of diethylene triamine, triethylene tetraamine and tetraethylene pentamine in the following ratio, wt.% Of the spent drilling fluid: Polyacrylamide 0.05-1.00 Liquid glass 0.1-1.5 Specified Polyethylene Polyamine 0.01-0.20