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rearrangement. The secondary and tertiary amines widely from oil industry wastes. IR spectrometry and gas used as a flotation agentThus, aliphatic amides were chromatography/mass spectrometry were conducted in synthesized based on the fatty acid mixtures obtained order to analysis of a mixture ofaliphatic fatty acid amides.
References:
1. Osichkina R. G., The raw material base of potash and halurgical industry in Uzbekistan, Uzbek chemistry journal, - 2001, - V2.
2. Gitis S. S., Glaz A. N., Ivanov A. V. Workshop on Organic Chemistry of Organic Synthesis, - Moscow, - 1991, - P 303.
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4. Reutov O. A., Kurs A. L., Butin K. P. Hofman rearrangement.Organic chemistry, Part 4. - Moscow. - 2004. - P. 367-368.
5. Yettiboeva L. A., Gapparov C., Kadirov O.Sh. The chromatographic analysis of fatty acids in the composition of waste of Gulistan fat-and-oil plant, Actual problems of analytical chemistry, IV Republican scientific conference, - 2014, - Volume 1, - P. 303-305.
DOI: http://dx.doi.org/10.20534/AJT-16-11.12-75-77
Mahamathozhaev Dilmurad Rahmatovich, Tashkent State Technical University, senior research fellow researcher of the department «Drilling oil and gas wells E-mail: [email protected]
Application of mud composition at the opening of unstable clay deposits
Abstract: This paper presents the results of laboratory studies on the development of the composition of inhibiting clay-free drilling fluid and the results of its industrial tests in drilled wells AK "Uzgeoburneftegaz". Keywords: montmorillonite, scree, landslide, taking the drilling tool, the oil bath that inhibits mud.
In the oil and gas fields in Uzbekistan there are powerful clay deposits consisting of montmorillonite, siltstone, mudstone, and others. Argillaceous rocks. Autopsies clay deposits is often accompanied by talus and landslides wells wall, caused by the interaction of the filtrate used clay mud with passable argillaceous rocks [1, 236-239].
For example, in the area occurred Darahtli № 2 sticking drilling tool due to violation ofthe integrity ofthe well bore. To eliminate the sticking of the drilling tool it took 2757 hours. That's the reason stated above in the squares Kokdumalak № 412, 428, Taylok № 9, № 20 North Shur-tan, Qamar № 1, Girsan № 29, № 35 and other Chul-kuvar occurred sticking drilling tool for the elimination of which spent a huge calendar time and material and technical resources [2, 168-170].
Due to the fact that the cut oil and gas wells, consists of different types of rocks and composition, will act not identical under identical conditions, the mud filtrate. Therefore, the most important factor in maintaining the stability of the borehole is the right choice of the type of
drilling mud and its composition, as well as technological parameters [3, 192-198].
The standard formulation of drilling fluids is regulated to maintain filtration indicator while drilling argillaceous rocks less than 10 cm3/30 minutes, which should be provided work reagents stub analyzer in an alkaline medium, ie. E. At a pH greater than 7, especially at elevated temperatures and salinity. But argillaceous rocks have minimum filtration capacity relative to the liquid hydrocarbon — oil (oil fields tires) and water based systems — muds.
At pH = 7 the concentration of hydronium ion (H30 +) and hydroxyl (OH-) is the same. In the case of drilling fluids with pH> 7 the equilibrium dissociation constant is displaced to the right, ie. E. The amount of hydroxyl ions dissociated increases. In this case, the diffusive mass transport begins concentration equalization between mud filtrate and Doi clay-pore, resulting in cell structure from compensation, in general, to weaken bonds between layers and, ultimately, to shattering rock at the borehole wall.
Section 8. Chemistry
To eliminate this effect the authors of [4, 30-31], was designed drilling fluid formulation with a pH = 6.5 ... 7.0 to shift the equilibrium dissociation constant of water left by the reaction:
H2O + H2O + OH- = ON3 - or 2H2O = H3O + OH-The proposed formulation does not contain chemicals that are in the structure Sodium (caustic soda, soda ash, and others.) Since at higher pH occurs first replacing ion-water type (hydronium) in the clay, and then replacing metal (potassium) of sodium ions. Control of pH and the calcium ions is performed inorganic potassium compounds.
The formulation of drilling mud with a pH of about 7 and an indicator of filtration of up to 20 cm
3/30 min VM-6 was successfully used in the drilling of deep wells, descent and cementing intermediate casing diameter of 219 mm to a depth of 4100 m in the range of occurrence of mudstone.
Given the experience of the application of the composition of the drilling fluid, proposed by the authors [4, 30-31], we have developed a composition of clay-free drilling fluid with inhibitory with pH less than 7 and a low filtration rate for borehole in an unstable clay deposits on the oil and gas fields of JSC "Uzgeoburneftegaz". The results of laboratory tests are shown in Table 1.
Table 1. - The composition and properties of drilling fluids intended for the opening of unstable clay deposits
№ Mud composition P> kg/m3 T c F, cm3/ 30 min T, K mm pH sludge, %
1. 1000 ml of water + 15 g PAA + 300g of NaCl + 50g HCl +30 g graphite + 100 ml of oil 1190 35 4.0 1.0 6.0 6.0
2. № 1 + 50% marble powder (Nurata) 1350 45 4.0 1.0 6.0 0
3. № 1 + 90% marble powder (Nurata) 1480 75 4.0 1.0 6.0 0
4. № 1 + 130% marble powder (Nurata) 1650 120 4.0 1.0 6.0 0
5. When heated № 5 at 900° C 1650 60 6.0 1.0 6.0 -
6. № 6 after cooling to 20 C 1650 125 3.0 1.0 6.0 0
As can be seen from Table 1 based on unhydrolyzed polyacrylamide can prepare a clay-free drilling fluids inhibitor with stable processing characteristics. With the introduction of marble powder can be easily adjusted value of the density of the developed composition of clay-free drilling fluid inhibition. Not unimportant advantage of the proposed composition of the mud is to preserve the original processing properties at high temperatures.
As the data in Table 1 in the preparation of a clay-free drilling fluids inhibiting we abandoned the use of clay, caustic and soda ash and polymer reactants such as 4 K, starch, CMC, VPRG, Uniflok. Also excludes the use of imported organic reagents breakers (CSSC, FXLS, RVSM, etc.), Which are widely used for the passage of clastic sediments to regulate the relative viscosity of drilling mud clay water-based.
On the basis of laboratory tests and received positive results of the composition of inhibiting mud recommended for industrial testing in the wells drilled NHC « Uzbekneftegaz»
Industrial testing of the composition of inhibiting clay-free drilling fluid is produced while drilling the borehole under the technical column on Chunagar Square № 20. First clayless inhibitory prepared fresh mud in
a volume of 180 m3, with the following technological parameters: density, 1250-1260 kg/m3; relative viscosity — 35 seconds; Filtering — 3.5-4.0 cm 3/30 min; the pH = 6.0-6.5. After that the replacement of the working circulating clayey mud inhibiting new mud. Drilling of the borehole was carried out using a diamond bit of the Chinese production. In the process of deepening wells circulating drilling fluid is easily separated from major cuttings and colloidal clay particles using vybrosito and sand separator. At the same time technological parameters of the circulating drilling mud remains unchanged, as small clay colloidal particles interacting with floccu-lant — non-hydrolyzed polyacrylamide aggregated to form a paste-like mass that can be easily removed with the help of treatment plants. Due to this recess during wellbore drilling process parameters circulating solution remained unchanged.
During the ascent and descent of the drilling tool is not seen tightening and planting tools. And this in turn indicates the termination of the hydration and swelling of clay rocks forming the walls of the wells. Prevention, the process of hydration and swelling of argillaceous rocks is provided by the simultaneous action of several inhibiting additives, as well as through the creation of the walls of
the well impermeable thin solid filter cake formed from a non-hydrolyzed polyacrylamide and marble powder. In addition, the use of the proposed composition of the mud help to prevent the formation of glands above the bit and calibrators.
With the application of the proposed composition of inhibiting mud hole to deepen the process was carried out without complications and accidents related to the instability of the borehole wall, and dramatically reduce the time spent on chemical treatment of circulating drilling mud. Rose, mechanical drilling speed in comparison with the use of clay mud, which is widely used in the practice of construction of oil and gas wells. In the process of deepening the wellbore average penetration rate was 8-10 m/h. And this in turn led to a reduction in the wellbore drilling time by a technical column in easily swell and collapsing clay deposits on the Square. Chunagar-20.
Casing safely lowered to the design depth and produced cementing. By obtaining the nominal diameter of the well № 20 Chunagar area, formed a solid impenetrable stone cement behind the casing. Due to what has raised the quality of well casing in the field and, ultimately, led to the improvement of technical and economic indicators of well construction.
Based on the industrial test composition on skv.№ 20 Square. Chunagar and obtained positive results, the proposed composition of inhibiting mud recommended for further use in drilled wells AK «Uzgeo-burneftegaz». For example, on the areas of Shurtan-295, New Alan-8, Yangi Karatepa 21, Ilim-12 proposed by the drilling has been successfully used for drilling a
borehole in clastic sediments composed of the swell and easily dispersible clay rocks.
As a result of research work on the development of the composition of inhibiting mud and held it for industrial testing in field conditions, the following conclusions:
1. Based on the analysis of geological and technical conditions for drilling oil and gas wells in Uzbekistan found that the most common complications associated with the loss of stability of the borehole, which manifest themselves in the form of landslides and avalanches of argillaceous rocks.
2. It is found that the stability of the well walls folded argillaceous rocks depends on numerous factors independent of each other. To ensure the integrity of the walls of wells during drilling and easily collapsing swellable clay deposits, it is expedient to use special inhibiting muds.
3. The new composition of the clay-free drilling fluid is inhibited to stabilize the well walls in clastic sediments. The distinguishing feature of the composition of the mud developed compared with other types of drilling muds is inhibiting exclude application of caustic soda and soda ash, clay and alkaline polymeric reagents and reactants of imported organic diluents at their preparation and chemical treatment.
4. It was found that the use of inhibiting mud based on non-hydrolyzed polyacrylamide and local inhibiting additives provide improved technical and economic indicators of well construction, due to the prevention of complications and accidents that occur in the process of deepening the wellbore in clastic sediments.
References:
1. Mahamathozhaev DR, FS Kurbanov Huzhamov H. R. Ingibiruyuschy mud to prevent landslides and avalanches wells wall//Collection of scientific works. International scientific-technical conference "Modern problems and ways of development of mineral resources of oil and gas potential" (22 November - 2012 November) - Part 1.
2. Mahamathozhaev D. R. The composition of inhibiting mud for drilling a borehole in clastic sediments//Pro-ceedings of the international conference dedicated to the 85th anniversary of academician Azad Khalil corners Mirzadzhanzade, - Baku, - 21-22 November - 2013.
3. Mahamathozhaev D. R. The drilling fluid for drilling a borehole in clastic sediments//Herald of Tashkent State Technical University. - Tashkent, - 2014. - No 3.
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