RU2561634C2 - Biopolymer drilling mud sbk-uni (plus) - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to biopolymer drilling mud used when drilling wells, including horizontal, slanted and recovery wells by sidetracking. The biopolymer drilling fluid contains, wt %: polymer fluid loss additive - carboxymethyl cellulose with degree of substitution of 300-1300 in the form of two types of carboxymethyl cellulose with a different degree of substitution in ratio of 1:1 2.4-3.2; a xanthane type biopolymer 0.2-0.5; lubricant additive - glycoil reagent 0.5-1.0; different-fraction filler - barium sulphate up to 40.0, bactericide 0.01-0.2; sodium hydroxide 0.01-0.06; water - the balance.

EFFECT: improved structural-rheological properties of the biopolymer drilling mud, high retention and transporting capacity, while maintaining filtration properties.

4 cl, 3 tbl, 8 ex

Description

The invention relates to polymer drilling fluids for drilling gas and oil wells, in particular to biopolymer drilling fluids (BPBR) used in drilling wells, including horizontal, directional, as well as for the restoration of wells by drilling second trunks.

Known wash liquid, which includes in wt. %: carbon-alkaline reagent (humates of alkali metals), which serve as a filter reducing agent, - 15; biopolymer "enposan" (dry matter) - 0.2-05; water - the rest (see Ukrainian Pat. No. 47493, IPC 6 C09K 7/00, 7/01, publ. July 15, 2002, Bull. No. 7). The disadvantage of the flushing fluid is insufficient structural and rheological properties, low rate of endurance and lack of salt tolerance.

Known biopolymer drilling fluid designed for drilling directional and horizontal wellbores (Russian patent No. 2236429, IPC 7 C09K 7/02, publ. September 20, 2004), which contains, by weight. %: xanthan biopolymer type Flo-Vis - 0.3-0.5, humate reagent (powder carbon-alkaline reagent - PUSHR) - 10.5-15.0, water - the rest. The disadvantage of this solution is low heat resistance (up to 80 ° C) and low resistance to the effects of polyvalent metal ions.

Known biopolymer drilling fluid (PROTOTYPE) (RF patent No. 2289603, IPC C09K 8/10 dated 04/13/2005 publ. 12/20/2006) containing a polymer filter reducing agent, xanthan-type biopolymer, surfactant, lubricant and water, as a surfactant and a lubricant additive of ethylene diamides of fatty acids - a condensation product of ethylene diamine and a phosphatide concentrate, as a polymeric filter reducing agent - polyanionic cellulose, or carboxymethyl cellulose, or carboxymethyloxy ethyl cellulose, or hydroxyethyl cellulose, or hydrolyzed polyacrylonitrile, and additionally - alkali metal humates — carbon-alkali reagent UCHR or potassium hydrogenate-humate reagent and alkali and / or alkaline earth metal salts — KCl, NaCl, CaCl ₂ , MgC _l2 , bischofite in the following ratio of components, wt. %: the specified filtration reducer 0.1-1.0, the xanthan type biopolymer 0.2-0.5, the indicated fatty acid ethylene diamides 0.05-3.0, the UShR or GKR 3.0-6.0, the indicated salts 3 , 0-40.0, the rest is water.

The disadvantage of this solution is the lack of structural and rheological properties, namely, not high retention, tolerance, lubrication and inhibitory ability.

The objective of the proposed technical solution is to obtain a highly inhibitory composition of the drilling fluid with a minimum solids content for opening productive formations (including horizontal wells) in unstable sediments, with high holding, carrying, lubricating and inhibiting ability, satisfying high environmental requirements for preserving the natural environment Wednesday.

The technical result of the invention is to improve the structural and rheological properties of biopolymer drilling mud (BPBR), which provides increased holding and transporting ability, while maintaining filtration properties.

The technical result is achieved by the fact that the biopolymer drilling fluid contains a polymer filter reducing agent - carboxymethyl cellulose, xanthan type biopolymer, lubricant and water, while carboxymethyl cellulose has a degree of substitution of 300-1300 and is used as two types of carboxymethyl cellulose with a different degree of substitution in the ratio 1: 1 , reagent glycoil as a lubricant additive and, in addition, a different-fraction weighting agent - barium sulfate, bactericide and sodium hydroxide in the following ratio of components ntov wt. %:

Xanthan type biopolymer (xanthan reagent) 0.2-0.5 Carboxymethyl cellulose with a degree of substitution of 300-1300 2.4-3.2 Variety weighting agent - barium sulfate up to 40.0 Bactericide 0.01-0.2 Reagent Glycoil 0.5-1.0 Sodium hydroxide 0.01-0.06 Water rest

Moreover, the drilling fluid has a specific gravity of 1020-1350 kg / m ³ .

The components of the inventive biopolymer drilling mud

As the xanthan reagent, any xanthan-based polysaccharide can be used.

The xanthan gum polymer is a naturally occurring high molecular weight polysaccharide that enhances the solubility of the solution (xanthan gum, Ket X, polyksan, gammaxan).

Xanthan type biopolymers are water-soluble powder polysaccharides obtained by treatment with bacteria of the type "xanthanas" - "Barazan D" (xanthan reagent - Halliburton / Baroid)

Carboxymethyl cellulose (CMC) - filtration reducer - anionic polymer reagent

KMTS-9n (degree of substitution 400 - Polycell CJSC). KMTS-9 V (degree of substitution 1000 - Polycell CJSC). CMC does not have toxic and irritating effects (see TU 2231-001-50664923-2005).

A multifraction weighting agent (barium sulfate) is a white powder (or a transparent crystal), practically insoluble in water (solubility 0.0015 g / l at 18 ° C) and other solvents, crystalline substance (Barit Ural OJSC)

Bactericide (LPE-32 - NPO Technolog) - provides complete suppression of sulfate-reducing bacteria, complete solubility in water eliminates oil pollution and ensures effective disinfection of adhesive forms of bacteria in stagnant zones. The bactericide belongs to hazard class 3, and when using it, precautionary measures must be observed (see TU 2458-324-05765670-2008).

Inhibitor (lubricant based on glycols): glycoil is an organic clay inhibitor that improves the lubricating properties of a solution (TU 0252-001-93231287-2006).

The reagent glycoil PG-40 (OAO Nizhnekamskneftekhim) is an oligomer of ethylene oxide (propylene) obtained by alkaline polymerization of ethylene oxide (propylene), TU 2422-130-05766801-2003.

Sodium hydroxide NaOH - caustic soda belongs to the second hazard class (see GOST 2263-79) (OJSC "Soda").

SBK-UNI (PLUS) biopolymer drilling mud has the environmental benefits of a water-based mud.

SBK-UNI (PLUS) biopolymer drilling mud can be prepared both in fresh water and in highly mineralized fluids.

The invention is shown in the examples described below.

The drilling fluid preparation unit should include a tank (fluid preparation unit) equipped with mechanical stirrers and an ejector for introducing bulk reagents.

Example 1

The method of preparation of 1 m ^{3 of} drilling fluid with a density of 1120 kg / m ³ with a concentration of biopolymer "Barazan D" (xanthan reagent - Halliburton / Baroid) 0.2% wt. consists in the following.

To prepare 1 m ^{3 of} drilling fluid with a density of 1120 kg / m ³ (on a fresh basis) the following reagents are sequentially introduced in a percentage ratio:

Barazan D (xanthan type biopolymer) 0.2% (xanthan reagent - Halliburton / Baroid) KMTS-9n (degree of substitution 400 - Polycell CJSC) 1.2% (Carboxymethyl cellulose) KMTS-9V (degree of substitution 1000 - Polycell CJSC) 1.2% (Carboxymethyl cellulose) Barite weighting compound (OJSC Barit Urala) 21.0% Bactericide (LET-32 - NPO Technolog) 0.01% Reagent glycoil PG-40 (OAO Nizhnekamskneftekhim 1,0% (Inhibitor - glycol-based lubricant additive) NaOH (Soda OJSC) 0.01% Water 75.38%

The reagents are introduced sequentially in this order, with Barazan D, KMTs-9n and KMTs-9v introduced through the ejector with an interval of 15 minutes per 1 bag of reagent. Otherwise, the formation of polymer lumps is possible, which in the future will not be able to completely bloom.

Example 2

The method of preparation of 1 m of drilling fluid with a density of 1350 kg / m ³ with a concentration of biopolymer "Barazan D" (xanthan reagent Halliburton / Baroid) 0.5% wt. consists in the following.

To prepare 1 m ^{3 of} drilling fluid with a density of 1350 kg / m ³ (on a fresh basis), the following reagents are sequentially introduced in a percentage ratio:

Barazan D (xanthan type biopolymer) 0.5% (xanthan reagent - Halliburton / Baroid) KMTS-9n (degree of substitution 400 - Polycell CJSC) 1.6% (Carboxymethyl cellulose) KMTS-9V (degree of substitution 1000 - Polycell CJSC) 1.6% (Carboxymethyl cellulose) Barite weighting compound (OJSC Barit Urala) 40.0% Bactericide (LET-32 - NPO Technolog) 0.2% Reagent glycoil PG-40 (OAO Nizhnekamskneftekhim 0.5% (Inhibitor - glycol-based lubricant additive) NaOH (Soda OJSC) 0.06% Water 55.54%

The reagents are introduced sequentially in this order, with Barazan D, KMTs-9n and KMTs-9v introduced through the ejector with an interval of 15 minutes per 1 bag of reagent. Otherwise, the formation of polymer lumps is possible, which in the future will not be able to completely bloom.

Example 3

The method of preparation of 1 m ^{3 of} drilling fluid with a density of 1350 kg / m ³ with a concentration of biopolymer "Barazan D" (xanthan reagent - Halliburton / Baroid) 0.5% wt. consists in the following.

To prepare 1 m ^{3 of} drilling fluid with a density of 1350 kg / m ³ (on a mineralized basis - formation water, with a density of 1060 kg / m ³ ), the following reagents are successively introduced in a percentage ratio:

Barazan D (xanthan type biopolymer) 0.5% (xanthan reagent - Halliburton / Baroid) KMTS-9n (degree of substitution 400 - Polycell CJSC) 1.6% (Carboxymethyl cellulose) KMTS-9V (degree of substitution 1000 - Polycell CJSC) 1.6% (Carboxymethyl cellulose) Barite weighting compound (OJSC Barit Urala) 35.0% Bactericide (LET-32 - NPO Technolog) 0.2% Reagent glycoil PG-40 (OAO Nizhnekamskneftekhim 0.5% (Inhibitor - glycol-based lubricant additive) NaOH (Soda OJSC) 0.06% Water 60.54%

The reagents are introduced sequentially in this order, with Barazan D, KMTs-9n and KMTs-9v introduced through the ejector with an interval of 15 minutes per 1 bag of reagent. Otherwise, the formation of polymer lumps is possible, which in the future will not be able to completely bloom.

Example 4

The method of preparation of 1 m ^{3 of} drilling fluid with a density of 1120 kg / m ³ with a concentration of biopolymer "Barazan D" (xanthan reagent - Halliburton / Baroid) 0.2% wt. consists in the following.

To prepare 1 m ^{3 of} drilling fluid with a density of 1120 kg / m ³ (on a mineralized basis - produced water, with a density of 1060 kg / m3), the following reagents are successively introduced in a percentage ratio:

Barazan D (xanthan type biopolymer) 0.2% (xanthan reagent - Halliburton / Baroid) KMTS-9n (degree of substitution 400 - Polycell CJSC) 1.2% (Carboxymethyl cellulose) KMTS-9V (degree of substitution 1000 - Polycell CJSC) 1.2% (Carboxymethyl cellulose) Barite weighting compound (OJSC Barit Urala) 10.0% Bactericide (LET-32 - NPO Technolog) 0.01% Reagent glycoil PG-40 (OAO Nizhnekamskneftekhim 1,0% (Inhibitor - glycol-based lubricant additive) NaOH (Soda OJSC) 0.01% Water 86.38%

The reagents are introduced sequentially in this order, with Barazan D, KMTs-9n and KMTs-9v introduced through the ejector with an interval of 15 minutes per 1 bag of reagent.

Otherwise, the formation of polymer lumps is possible, which in the future will not be able to completely bloom.

Example 5

The method of preparation of 1 m ^{3 of} drilling fluid with a density of 1120 kg / m ³ with a concentration of biopolymer "Barazan D" (xanthan reagent - Halliburton / Baroid) 0.1% wt. consists in the following.

To prepare 1 m ^{3 of} drilling fluid with a density of 1120 kg / m ³ (on a fresh basis) the following reagents are sequentially introduced in a percentage ratio:

Barazan D (xanthan type biopolymer) 0.1% (xanthan reagent - Halliburton / Baroid) KMTS-9n (degree of substitution 400 - Polycell CJSC) 1.2% (Carboxymethyl cellulose) KMTS-9V (degree of substitution 1000 - Polycell CJSC) 1.2% (Carboxymethyl cellulose) Barite weighting compound (OJSC Barit Urala) 21.0% Bactericide (LET-32 - NPO Technolog) 0.01% Reagent glycoil PG-40 (OAO Nizhnekamskneftekhim 1,0% (Inhibitor - glycol-based lubricant additive) NaOH (Soda OJSC) 0.01% Water 75.48%

The reagents are introduced sequentially in this order, with Barazan D, KMTs-9n and KMTs-9v introduced through the ejector with an interval of 15 minutes per 1 bag of reagent. Otherwise, the formation of polymer lumps is possible, which in the future will not be able to completely bloom.

Example 6

The method of preparation of 1 m ^{3 of} drilling fluid with a density of 1350 kg / m ³ with a concentration of biopolymer "Barazan D" (xanthan reagent - Halliburton / Baroid) of 0.6% wt. consists in the following.

To prepare 1 m ^{3 of} drilling fluid with a density of 1350 kg / m ³ (on a fresh basis), the following reagents are sequentially introduced in a percentage ratio:

Barazan D (xanthan type biopolymer) 0.6% (xanthan reagent - Halliburton / Baroid) KMTS-9n (degree of substitution 400 - Polycell CJSC) 1.6% (Carboxymethyl cellulose) KMTS-9V (degree of substitution 1000 - Polycell CJSC) 1.6% (Carboxymethyl cellulose) Barite weighting compound (OJSC Barit Urala) 40.0% Bactericide (LET-32 - NPO Technolog) 0.2% Reagent glycoil PG-40 (OAO Nizhnekamskneftekhim 0.5% (Inhibitor - glycol-based lubricant additive) NaOH (Soda OJSC) 0.06% Water 55.44%

The reagents are introduced sequentially in this order, with Barazan D, KMTs-9n and KMTs-9v introduced through the ejector with an interval of 15 minutes per 1 bag of reagent. Otherwise, the formation of polymer lumps is possible, which in the future will not be able to completely bloom.

Example 7

The method of preparation of 1 m ^{3 of} drilling fluid with a density of 1120 kg / m ³ with a concentration of biopolymer "Barazan D" (xanthan reagent - Halliburton / Baroid) 0.1% wt. consists in the following.

To prepare 1 m ^{3 of} drilling fluid with a density of 1120 kg / m ³ (on a mineralized basis - produced water, with a density of 1060 kg / m ³ ), the following reagents are introduced sequentially in a percentage ratio:

Barazan D (xanthan type biopolymer) 0.1% (xanthan reagent - Halliburton / Baroid) KMTS-9n (degree of substitution 400 - Polycell CJSC) 1.2% (Carboxymethyl cellulose) KMTS-9V (degree of substitution 1000 - Polycell CJSC) 1.2% (Carboxymethyl cellulose) Barite weighting compound (OJSC Barit Urala) 10.0% Bactericide (LET-32 - NPO Technolog) 0.01% Reagent glycoil PG-40 (OAO Nizhnekamskneftekhim 1,0% (Inhibitor - glycol-based lubricant additive) NaOH (Soda OJSC) 0.01% Water 86.48%

The reagents are introduced sequentially in this order, with Barazan D, KMTs-9n and KMTs-9v introduced through the ejector with an interval of 15 minutes per 1 bag of reagent.

Otherwise, the formation of polymer lumps is possible, which in the future will not be able to completely dissolve

Example 8

The method of preparation of 1 m ^{3 of} drilling fluid with a density of 1350 kg / m ³ with a concentration of biopolymer "Barazan D" (xanthan reagent - Halliburton / Baroid) of 0.6% wt. consists in the following.

To prepare 1 m ^{3 of} drilling fluid with a density of 1350 kg / m ³ (on a mineralized basis - formation water, with a density of 1060 kg / m ³ ), the following reagents are successively introduced in a percentage ratio:

Barazan D (xanthan type biopolymer) 0.6% (xanthan reagent - Halliburton / Baroid) KMTS-9n (degree of substitution 400 - Polycell CJSC) 1.6% (Carboxymethyl cellulose) KMTS-9V (degree of substitution 1000 - Polycell CJSC) 1.6% (Carboxymethyl cellulose) Barite weighting compound (OJSC Barit Urala) 35.0% Bactericide (LET-32 - NPO Technolog) 0.2% Reagent glycoil PG-40 (OAO Nizhnekamskneftekhim 0.5% (Inhibitor - glycol-based lubricant additive) NaOH (Soda OJSC) 0.06% Water 60.44%

The reagents are introduced sequentially in this order, with Barazan D, KMTs-9n and KMTs-9v introduced through the ejector with an interval of 15 minutes per 1 bag of reagent. Otherwise, the formation of polymer lumps is possible, which in the future will not be able to completely bloom.

The properties of the SBK-UNI biopolymer drilling fluid (PLUS) were measured according to API R.P. 13B-1 (water-based mud control method).

Table 1 shows examples of the preparation of biopolymer drilling mud at various concentrations of components and data on the lubricating, inhibiting, anti-seizing properties of biopolymer drilling mud at various concentrations of components.

Table 1a shows examples with boundary minimum and maximum biopolymer contents.

Table 2 shows the comparative parameters of the inventive biopolymer drilling fluid CEK-UNI (PLUS) with the parameters of the closest analogue (prototype).

BP - biopolymer,

CMC - carboxyl methyl cellulose

ρ is the density

T - conditional viscosity

F - filterability

PV - plastic viscosity

AV - apparent viscosity

YP - dynamic shear stress

GelsAPI _{10 sec / 10 min} - static shear stress.

From table 2 it is seen that the inventive biopolymer drilling fluid has the best structural and rheological properties.

From the above examples it is seen that the optimal polymer concentration is 0.2-0.5%. When changing concentrations, the solution does not have the necessary requirements. An increase in the concentration of biopolymer in excess of 0.5% is impractical, since the consumption of chemicals is increased, and the structural-rheological and filtration properties are not significantly improved.

With this excess of the amount of barium sulfate over 40%, the density of the solution will be above 1.35 g / cm3; if the amount of xanthan reagent and carboxymethyl cellulose exceeds 1.6%, the rheological parameters will be exceeded (conditional viscosity, static and dynamic shear stress). Excessive concentration of bactericide does not have any effect, only leads to a rise in price of the solution. Exceeding the indicated inhibitor values does not lead to a harmful effect, but only to an increase in the cost of 1 m ^{3 of} drilling fluid.

The main advantage of biopolymer solutions is their ability to possess the properties of a solid at low shear rates and when at rest and the properties of a liquid at high speeds. These properties of a biopolymer solution are characterized by its viscosity at low shear rates.

The permeability recovery coefficient characterizes the degree of influence of the drilling fluid on the reservoir properties of the reservoir.

The low value of the separation pressure of the filter cake during development allows the use of SBK-UNI (PLUS) biopolymer drilling fluid for opening productive formations.

SBK-UNI (PLUS) biopolymer drilling mud has excellent inhibitory properties, provides high penetration rate, reduces downtime, ensures well stability and contributes to the effective removal of cuttings - all this with minimal environmental impact and adequate cost.

When using SBK-UNI (PLUS) biopolymer drilling mud in the fields, a low dilution coefficient and the possibility of preparing the mud from environmentally friendly reagents were noted.

When using SBK-UNI biopolymer drilling fluid (PLUS), inhibited sludge particles of nominal size enter the solution, which contributes to the excellent operation of the cleaning equipment and significantly facilitates the assessment of the formation properties. An extremely low content of drill cuttings is maintained, which reduces the dilution coefficient and the cost of disposal of drilling waste.

Drilling fluid preparation and cleaning during well drilling is carried out using standard equipment

SBK-LINI (PLUS) biopolymer drilling mud has the environmental benefits of a water-based mud. It can be prepared both in fresh water and in highly mineralized liquids.

It is characteristic of a hydrocarbon-based solution with the environmental benefits of a water-based solution.

The relatively small number of components used to prepare the SBK-UNI biopolymer drilling fluid (PLUS) provides greater freedom for a particular application.

A small number of components also means ease of system maintenance and lower overall solution cost.

The claimed technical solution meets the criteria of "novelty" and "inventive step", since no similar solutions have been identified in the art and it is not explicitly obvious to a specialist.

The claimed technical solution meets the criterion of "industrial applicability", since the claimed biopolymer drilling fluid can be obtained from known means and by known methods.

Claims (4)

1. Biopolymer drilling fluid containing a polymer filtration reducer - carboxymethyl cellulose, xanthan type biopolymer, lubricant and water, characterized in that it contains carboxymethyl cellulose with a degree of substitution of 300-1300 in the form of two types of carboxymethyl cellulose with a different degree of substitution in the ratio 1: 1, reagent glycoil as a lubricant additive and, in addition, a different-fraction weighting agent - barium sulfate, bactericide and sodium hydroxide in the following ratio of components, wt. %:
Xanthan type biopolymer (xanthan reagent) 0.2-0.5 Carboxymethyl cellulose with a degree of substitution of 300-1300 2.4-3.2 Variety weighting agent - barium sulfate up to 40,0 Bactericide 0.01-0.2 Reagent Glycoil 0.5-1.0 Sodium hydroxide 0.01-0.06 Water rest 2. Biopolymer drilling fluid according to claim 1, characterized in that it contains mineralized water as water. 3. Biopolymer drilling fluid according to claim 1, characterized in that the xanthan type biopolymer can be any xanthan based polysaccharide. 4. Biopolymer drilling fluid according to claim 1, characterized in that the glycoil PG-40 reagent is used as a lubricant additive.