RU2555023C1 - Reagent for treating drilling mud - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: reagent for treating drilling mud contains 94-96 wt % ferrochrome lignosulphonate and 4-6 wt % ammonium polyphosphate.

EFFECT: improved dilution properties of the reagent in salt mud, high thermal stability and environmental safety of the reagent.

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Description

The invention relates to the field of compositions for the oil and gas industry and can be used in the manufacture of reagents for the treatment of drilling fluids used in drilling oil and gas wells. Known powdered ferrochrome lignosulfonate, which is a dried product of the processing of a concentrate of sulphite-yeast stillage with iron and chromium salts in an acidic environment [Kister ET. Chemical treatment of drilling fluids. M .: Nedra, 1972, p.147].

The closest in technical essence and the achieved result is the reagent [and.with. USSR No. 775117. Reagent for processing drilling fluids. Cl. C09K 7/02. Publ. 10.30.1980, bull. No. 40] for processing drilling fluids containing ferrochrome lignosulfonate and a phosphorus-containing compound, while the drilling fluid contains tributyl phosphate as a phosphorus-containing compound in the following ratio of ingredients, wt.%:

ferrochrome lignosulfonate 99.0-99.5 tributyl phosphate 0.5-1.0

The reagent has enhanced thinning properties in mineralized drilling fluids, additionally contains tributyl phosphate.

The disadvantages of the known reagents are the insufficient effect of dilution of mineralized solutions and low thermal stability.

The technical result to which the invention is directed is to increase the fluidizing properties of the reagent in mineralized drilling fluids, increase the thermal stability and environmental safety of the reagent.

The task is achieved by the proposed reagent for processing drilling fluids containing ferrochrome lignosulfonate and a phosphorus-containing compound, while the reagent for processing drilling fluids as a phosphorus-containing compound contains ammonium polyphosphate in the following ratio of ingredients, wt.%:

ferrochrome lignosulfonate 94-96 ammonium polyphosphate 4-6

Ammonium polyphosphate does not interact with salts, therefore, this reagent effectively reduces the viscosity of mineralized solutions. As well as the introduction of polyphosphate increases the thermal stability of the reagent.

The drilling fluid treatment reagent is prepared by dispersing the calculated amount of powdered ammonium polyphosphate in the liquid mass of the finished ferrochrome lignosulfonate. For uniform dispersion of ammonium polyphosphate, these components are thoroughly mixed in the reactor with an anchor mixer for 1 hour at a temperature of 60-70 ° C. The prepared mass is dried in a spray dryer to obtain the target product.

The reagent according to the invention is a powder. The production of the proposed reagent can be arranged on the basis of lignosulfonate reagents manufactured by the industry (FHLS-M, Oxil-s / m) without significant changes in the technological scheme.

Subsequently, when the resulting reagent is introduced into the drilling fluid, ammonium polyphosphate reduces the hydrogen bonds of the hydrated surfaces of the polymer reagent particles at the phase boundary, thereby reducing the viscosity of the drilling fluids.

To obtain the reagent, ammonium polyphosphate is introduced into the liquid mass of ferrochrome lignosulfonate at various ratios (Table 1) to obtain a reagent with the content of ferrochromlignosulfonate in the range 93.5-96.5%, and ammonium polyphosphate - 3.5-6.5%.

The obtained samples of the powdered reagent were introduced into a clay suspension mineralized with sodium chloride. The resulting suspensions after daily aging and subsequent two hours of intensive stirring were analyzed for density ρ in g / cm ³ ; conditional viscosity of hydrocarbons in s; kinematic η PL and dynamic viscosity τ ₀ , in MPa · s; statistical shear stress, determined after 1 and 10 min in dPa, filtration rate in cm ³ with a filtration duration of 30 minutes, and the pH of the solution. In this case, suspensions are prepared with a content of 1% of the mass of the proposed reagent based on ferrochrome lignosulfonate and ammonium polyphosphate. The tests were carried out in three temperature conditions: 20 ° C, 130 ° C, 170 ° C. The test results are presented in table 2.

The test results show that the introduction of ammonium polyphosphate into the reagent in an amount of 3.5% leads to a decrease in the nominal viscosity of the clay solution, at temperatures of 20 ° C and 130 ° C, from 60 s to 28-30 s, which is a dilution efficiency of 50- 53%. With an increase in temperature exposure to 170 ° C, an increase in the conditional viscosity of the clay solution is observed from 60 to 62 s. There is no liquefaction efficiency at this temperature condition.

With the introduction of 4.0-5.0% additives of ammonium polyphosphate leads to an effective decrease in the nominal viscosity of the suspension at temperatures of 20 ° C and 130 ° C from 60 s to 24-28 s, which is the effectiveness of the fluidizing ability of 53-60%. With an increase in temperature exposure to 170 ° C, a decrease in the efficiency of dilution to 20–40% is observed, with changes in the values of the conditional viscosity of the clay solution from 60 s to 36–48 s.

With an increase in the content of ammonium polyphosphate to 6.0%, the viscosity of the suspension at all temperature conditions from 20 ° to 170 ° C decreases from 60 s to 22-24 s. The effectiveness of the fluidizing ability is 60-63%.

With the introduction of a 6.5% addition of ammonium polyphosphate, a certain decrease in the dilution efficiency is observed at all temperature conditions and amounts to 57-61%, with a change in the nominal viscosity from 60 s to 23-26 s.

In the absence of ammonium polyphosphate in the reagent, a decrease in the viscosity of the drilling fluid is observed in the range from 60 to 37 s, while the thinning effect is 38.0% and is kept in the temperature range from 20 ° C to 130 ° C.

Thus, the use of the reagent according to the invention makes it possible to increase the fluidizing effect to 60-63% with changes in the values of the conditional viscosity of the clay solution from 60 s to 22-24 s and to increase the operating temperature range from 20 to 170 ° C.

The results of the study of the effectiveness of the proposed reagent on the technological parameters of a clay solution in the presence of 10% wt., Sodium chloride are shown in table 3.

When considering the effect of a ferrochrome lignosulfonate reagent modified with ammonium polyphosphate (additive 6%) on clay solutions with NaCl up to 10% (table 3), the following conclusions can be made. With an increase in the concentration of modified ferrochrome lignosulfonate reagents to 3% in all solutions, a smooth decrease in the filtration rate with increasing viscosity is observed, but the reagent modified with ammonium polyphosphate introduced as a 1% additive works most effectively (as a protective colloid).

The developed reagent, representing ferrochrome lignosulfonate modified with ammonium polyphosphate in an amount of 4-6%, allows to achieve an effective reduction in the conditional viscosity of a clay solution in the temperature regime from 20 to 170 ° C, and also act as a protective colloid in low-clay solutions containing up to 10% chloride sodium.

Claims (1)

A drilling fluid treatment reagent containing ferrochrome lignosulfonate and a phosphorus-containing compound, characterized in that the drilling fluid processing reagent as a phosphorus-containing compound contains ammonium polyphosphate in the following ratio of ingredients, wt.%:
ferrochrome lignosulfonate 94-96 ammonium polyphosphate 4-6.