RU2447121C2 - Hydrocarbon-based drilling mud - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to oil and gas extraction industry and specifically to process liquids and drilling compositions used in well construction for drilling in. The hydrocarbon-based drilling mud contains a filtrate agent in form of either tall oil or biglital or tall oil rosin glycerine ether combined with bitumen mastic, with the following ratio of components, wt %: diesel fuel 36-40; mineralised water 50-59; emultal 1-2; organobentonite 1-2; filtrate agent 2-5.

EFFECT: high electrical stability and improved rheological and filtration properties of the drilling mud.

2 tbl

Description

The invention relates to the oil and gas industry, in particular to process fluids and compositions used in well construction.

Known drilling mud - lime-bitumen, including diesel fuel, oxidized bitumen, sulfonol, quicklime and water / Ryazanov Y.A. Encyclopedia of drilling fluids. Orenburg, Annals 2005, pp. 156-159 /.

The disadvantage of this solution is the multicomponent and high consumption of reagents, strict regulation of the content of reagents, which is not always feasible in the process of drilling, unsatisfactory rheological indicators, the complexity of preparation, consisting in the fact that the "dissolution" of bitumen is carried out at high temperature (70-90 ° C) .

The closest technical solution is a highly concentrated invert emulsion (VER), which includes a hydrocarbon medium, an aqueous phase (saline water), an emulsifier (emulsifier), a filtration reducer SMAD-1 and organobentonite in the following ratio of components, in wt.% / Mikheev V.L. Technological properties of drilling fluids. M., Nedra, 1979, p. 211-212 /:

Diesel fuel 30-35 Mineralized water 60-65 Emultal 0.5-2.0 SMAD-1 2.0-5.0 Organobentonite 0.5-2.0

The disadvantage of this solution is the low value of electrical stability and unsatisfactory rheological parameters.

The problem to which the present invention is directed, is to obtain a hydrocarbon-based drilling fluid intended for opening productive formations during well construction.

The technical result achieved by the invention is to eliminate the disadvantages of the known drilling fluid and consists in increasing the values of electrical stability and improving the rheological and filtration parameters of the drilling fluid.

This technical result is achieved due to the fact that in a drilling fluid based on hydrocarbon, including diesel fuel, organophilic bentonite (organobentonite), the aqueous phase mineralized with salts - electrolytes, an emulsion and a filtration reducer, either tall oil or bigittle is used as a filtration reducer , or glycerin tall oil rosin ether together with bituminous mastic in the following ratio of components, in wt.%:

Diesel fuel 36-40 Mineralized water 50-59 Emultal 1-2 Organobentonite 1-2 Filtration Reducer 2-5

A quantitative change in the components of the solution and the addition of tall oil, or biglital, or glycerol tall oil rosin ester together with bituminous mastic (EHTC) as a filtration reducing agent instead of the SMAD-1 filtration reducing agent used in the closest known drilling fluid can improve rheological and filtration rates and increase the electrostability of the solution. As mineralized water, you can use brines of sodium, calcium and zinc salts, for example chloride, bromide, formate, sodium acetate, or chloride, calcium bromide, or chloride, zinc bromide.

Tables 1 and 2 show the properties of drilling fluids obtained as a result of preparation, including the mixing of mineralized water with electrolyte salts with diesel fuel, emulsion, organobentonite and a filtration reducer, after which the solution is subjected to mechanical treatment. It is advisable to use a percussion apparatus, such as a disintegrator, equipped with rotating disks in two opposite directions at a speed of 10,000 to 12,000 rpm.

Table 1 shows the experimentally obtained information about the change in the technological parameters of hydrocarbon-based drilling fluids, which include a filtration reducer - SMAD-1, used in the known solution. Table 2 contains information about the technological indicators obtained experimentally, of the inventive hydrocarbon-based drilling fluids, which include, as a filtration reducer, either tall oil, or biglital, or tall oil glycerin ether together with bitumen mastic, used in the inventive drilling mud instead of smad-1. The following notation is used in tables 1, 2: Ф - filtration rate, τ ₀ - dynamic shear stress, U - electric stability of the drilling fluid, η - plastic viscosity, n - rotational speed of the disintegrator disks. Lines 1-3 of table 1 contain data on the properties of a well-known drilling fluid, which includes a filtration reducer SMAD-1, when the disintegrator is not used, and lines 4-6 of table 1 show the performance of the same drilling fluid, depending from the intensity of exposure in the disintegrator.

Table 2 shows data on the electrical stability, rheological and filtration properties of the inventive drilling fluids with various filtration reducers. For example, the biglital reagent is a mixture of bituminous mastic with glital (TU 2458-019-32957739-01), and EGTK is tall oil glycerin ether. Table 2 also shows data on filtration rates, dynamic shear stress, electrical stability of the drilling fluid, plastic viscosity and rotational speed of the disintegrator disks when such filtration reducers as tall oil are introduced into the drilling fluid (TU 13-0281078-119-89, TU 13- 00281074-26-95), bigital, EGTK (TU 13-00281074-162-95) in combination with bitumen mastic (TU 1415-001-5) in the case when the disintegrator is not used, as well as during disintegration activation of the drilling fluid.

The disintegrator used for the preparation of drilling fluids is a percussion apparatus in which two disks rotating towards each other are equipped with beater fingers (see V.I. Molchanov, O.G. Selezneva, E.N. Zhirnov. Activation of minerals during grinding. M. 1988, p. 159-160). Fingers of one disc during rotation pass between the fingers of another disc. Shredding - activation is carried out through multiple strokes, the frequency of which depends on the speed of rotation of the disks. Moreover, the greater the number of shocks given to the particles of a substance, and, consequently, the smaller the interval between successive shocks, the stronger the activation of materials that are subjected to disintegration processing.

The inventive solutions are prepared by introducing the components of the solution in a certain sequence: hydrocarbon medium → emulsional → reagents filtration reducers → organobentonite → aqueous phase. The prepared mixture is subjected to mechanochemical activation by means of a disintegrator with two disks equipped with beater fingers rotating around the axes in opposite directions. The disks are designed in such a way that when they rotate, the beat fingers of the first disk are located between the beat fingers of the second disk. To assess the degree of influence of disintegration processing on the technological parameters of the drilling fluid, the following methodology was used. First, drilling fluid was prepared using a laboratory stirrer. Then, the drilling fluid was subjected to disintegration processing in a mode characterized by the speed of rotation of the disks with the fingers, equal to from 6000 to 18000 rpm.

The results of an experimental verification of hydrocarbon-based drilling fluids shown in tables 1 and 2 show that to maintain the fluid filtration rate below 4 cm ³ and with an increase in electrical stability to 200 V or more, it is necessary to use disintegrator processing in the preparation of the drilling fluid characterized by a disk rotation speed of 10,000 to 12,000 rpm (Table 2, Clause 1.2, 1.3, 2.2, 2.3, 3.2, 3.3, 4.2, 4.3, 5.2, 5.3, 6.2, 6.3, 7.2, 7.3, 8.2, 8.3 , 9.2, 9.3, 10.2, 10.3). A further increase in the intensity of exposure (increase in the number of revolutions) practically does not change the performance of the solution (see table 2, 1.4, 2.4, 3.4, 4.4, 5.4, 6.4, 7.4, 8.4, 9.4, 10.4), but leads to an increase in energy consumption by solution activation. A decrease in the intensity of disintegrator activation leads to a deterioration in the performance of the solution and a decrease in the degree of activation of the solution (see Clause 1.1, 2.1, 3.1, 4.1, 5.1, 6.1, 7.1, 8.1, 9.1, 10.1, Table 2).

Hydrocarbon-based drilling mud

Table 1. No. The composition of the solution,% F, cm ³ U, B τ ₀ , Pa η, MPa · s n rpm one 2 3 four 5 6 7 one Diesel fuel 34 8 fifty eleven 22 Mineralized Water 61 Emultal 2.0 SMAD-1 2.0 Organobentonite 2.0 2 Diesel 31 5 fifty 9 34 Mineralized Water 60 Emultal 2.0 SMAD-1 5.0 Organobentonite 2.0 3 Diesel 33 10 less than 50 3 thirty Mineralized Water 60 Emultal 1.0 SMAD-1 5.0 Organobentonite 1.0 four Diesel 35 8 one hundred 13 twenty 6000 Mineralized water 59 7 200 fourteen twenty 9000 Emultal 2.0 3 500 twenty 22 10,000 SMAD-1 2.0 2 600 22 23 12000 Organobentonite 2.0 four 600 eighteen 23 15,000 5 Diesel 35 5 one hundred eleven 35 6000 Mineralized Water 56 5 250 13 33 9000 Emultal 2.0 2 650 22 26 10,000 SMAD-1 5.0 one 700 25 25 12000 Organobentonite 2.0 3 650 19 27 15,000 6 Diesel 35 9 fifty four 32 6000 Mineralized water 58 8 150 6 28 9000 Emultal 1.0 3 500 eleven 24 10,000 SMAD-1 5.0 2 500 13 24 12000 Organobentonite 1.0 four 500 eleven 26 15,000

Claims (1)

A hydrocarbon-based drilling fluid comprising diesel fuel, organobentonite, an aqueous phase mineralized with electrolyte salts, an emulsifier and a filtration reducer, characterized in that it contains tall oil, or biglital, or tall oil glycerin ether together with bituminous mastic as a filtration reducer in the following ratio of components, wt.%:
Diesel fuel 36-40 The aqueous phase mineralized with electrolyte salts 50-59 Emultal 1-2 Organobentonite 1-2 Filtration Reducer 2-5