203
DEVELOPMENT OF NEW CHEMICAL REAGENT BASED ON LOCAL AND RAW
MATERIALS FOR OIL AND GAS INDUSTRY
Kobilov Nodirbek., Khamidov Basit, Shukurov Abror.,
*
Kodirov Sarvar.
Institut of General and Inorganic Chemistry of Academy of Science
*
Karshi professional school, ** University of Economics and pedagogy
Tashkent ., Uzbekistan
+9989972604607, nodirbekdoc2020@gmail.com
Abstract.
The article presents the ways of improvement and development new weighted
mud receipt based on composite lubricant from local raw materials and industrial wastes for drilling
oil and gas wells.
In the process of building oil and gas wells to maintain the stability of the walls,
to prevent the flow of salts, and to prevent the penetration of formation fluids into the well, it
becomes necessary to increase the density of the drilling fluid, which can be accomplished by
introducing components with increased density.
As the demand for energy increases, harsh and extreme environments are explored for
hydrocarbon; and deeper wells have been drilled to reach targets in formations with very high
temperatures and pressures. The successful completion of an oil well depends to a considerable
extent on the properties of the drilling fluid. Drilling fluids serve several fundamental functions: (i)
to remove the cuttings generated by the drill bit from the borehole, (ii) to control the downhole
formation pressures, (iii) to overcome the fluid pressure of the formation, (iv) to avoid damage to
the producing formation and (v) to cool and lubricate the drill bit, etc [1,2].
Present time for obtaining and development of drilling fluids for drilling oil and gas wells
use more than 4000 kind of chemicals in the world. Such as Carboxymethylcellulose,
polyacrylamide, hydrolyzed polyacrylonitrile, ferrochrome-lignosulphonate, grafite, chrompick,
NaOH, Na
2
CO
3
and others. In the Republic of Uzbekistan for drilling oil and gas wells use about
3,5-4 thousand ton chemical reagents every year. Domestic chemicals are not fully meet the
requirements of geological and technical conditions of wells. The quality of the construction of oil
and gas wells, and the quality of the opening of the productive formation, largely depends on the
used drilling mud because the drilling fluid is a technological fluid that interacts with the newly
opened rock. In all cotton producing countries and factories proceeding cotton seeds gossypol resin
is formed as a final product, which has a viscous-fluid consistency, and now find its effective
implementation. The transformation of the viscous fluid gossypol resin into a powdered material by
modification of the various ingredients of the organic and inorganic origin can bring to the
commercial introduction of the products and to expand the field of efficient use in large-tonnage
quantities [3].
The structure, composition and physicochemical properties of the domestic composite
chemical reagent for drilling fluids, the waste of “Ferganazot” JSC— carbonate-polymer sludge,
soda ash and caustic soda, and Na-carboxymethylcellulose “Carbonam” with 500 polymerization
degree were studied. Next, the physicochemical properties of mineral weighting agents were
investigated - red clay, marble flour, dolomite, scale, hematite and barite (table 1).
Table 1 shows comparative data on the results of studies of the physicochemical properties of the
studied organomineral raw materials as weighting agents for drilling fluids.
New compositions of Lubricants and technology of obtaining for production of
composite polymer lubricants by using of low molecular weight sodium carboxymethylcellulose,
alkali, water-soluble modified powdered gossypol resins and organic-mineral additives of various
ratios to improve the physical and chemical properties of drilling fluids have been developed.
Water-soluble modified powdery resin contains hydrophobic additives based on sodium salt of fatty
acids and ionic surfactants. The use of these reagents for drilling fluids used in drilling oil and gas
wells ensures the preservation of the regulated rheological and filtration properties of polymer
systems at 80-190 ° C for 30-40 hours. Method of obtaining new composite lubricants based on
physical and chemical modification of initial materials on various ratios, environment and regime.
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All the physical, chemical and technological parameters of drilling fluids based on composite
chemical reagents have been tested in accordance with API standards.
In the development of new composite chemical reagents for stabilization drilling fluids for
drilling oil and gas wells we used mainly waste of oil and fat production-gossypol resin, as well as
low mass carboxymethylcellulose. Gossypol resin consists of 52 to 64 of free fatty acids and their
derivatives, and the rest-a product of condensation and polymerization of gossypol and its
transformation, resulting from extraction of cottonseed oil, mainly in the process of distillation of
fatty acids from soapstok. In the gossypol resin found 12% of the nitrogen containing compounds,
36% of the transformation products of gossypol fatty and oxide fatty acids. It is a homogenous fluid
mass from dark brown to black color. This reagent plays main lubricant for drilling fluids.
Polymers are used heavily in the oil industry for controlling the drilling fluid properties or for
enhanced oil recovery applications to extract the heavy oil.
Have been developed new chemical reagents for drilling in salt and chemical corrosive
environments, as they are stable to cations of polyvalent salts (Mg
++
, Ca
++
, Na
+
, K
+
).
Composite chemical reagent (CCR) is mainly about 60-65% gossypol resin and has a high lubricity
due to the content in its composition of about 35-40% of polymerized fatty acids, pigment, glycerin
and other components. These reagents as a surfactants serve to emulsify oil with water, increase
drilling speed because of low coefficient of friction, play role as lubricant and corrosion inhibitor.
Results of analyses were given in the table 1
Table 1
Physico-chemical properties of weighting materials
Name
of
weightings
Physical chemical properties
Density,
g/sm
3
Mohs hardness
Sieve residue,
0071, %
Humidity, %
рН
Clay (Navbahor
bentonite)
2,55-2,65
2-2,5
5
2
7,5
Marble flour
2,6-2,70
2,5-3,0
6
1,5
7-8
CPS
2,7-2,75
2,5-3,0
6
1,8
11-12
Dolomite
2,8-2,9
2,5-3,0
6,5
1,2
7-8
Barite (Uz)
3,85-4,1
3,0-3,5
10
1,9
7-7,5
Barite (Кz)
4,1-4,2
3,0-3,5
8
1,3
7
Barite (Ru)
4,15-4,25
3,0-3,5
7
1,1
7-8
Okalina
4,3-4,5
5-6
8
0,9
7-7,5
Hematite
4,4-4,6
5-7
9
0,8
7-7,5
Developed new composite lubricant based on local raw materials give to drilling fluids
high lubricity. It can be seen that developed composite chemical reagents have a multifunction. As a
result of research and study of the physical and chemical properties of the developed composite
chemical reagents base on local and raw materials, wastes as well as weighting agents have been
proposed new compositions of drilling fluids. New receipt of drilling fluids based on developed
composite lubricant and weighting agent were recommended for use in drilling oil and gas wells
with abnormally high reservoir pressure (AHRP).
References
1.
Emmanuel U.A., Godpower C.E., Ghasem N., Aminu A.Y.,Abdullahi A.A., Bello S., 2019. Water based
drilling fluids for high temperature applications and water sensitive and dispersible shale formations. J.
Petrol. Sci. Eng. 175 .1028-1038. http:/doi.org/10.1016/j.petrol.2019.01.002.
2.
Reyn Caenn., HCH Darley., George R. Gray. 2017. Composition and properties of drilling and
completion fluids. Seventh edition. Elsevier. Amsterdam
3.
Kobilov N. S., Negmatova K.S., Sharifov G’.N., Rakhimov X.Y. 2016. Сomposite chemical reagent
for stabilization heavy mud for drilling salt-anhydrite layer of oil and gas wells// European applied
science. II. Germany, pp 50-52.
