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12NPWR was spent. Round-trip operations were made without tightening and seats. During the drilling process, water solution NPWR 0,2-0,4% from the capacity of solution (to the dry substance) was added to circulating solution. Oil in amount of 5-7% was added to solution as an lubricating component. The temperature in the depth of 4200m, was 115-120 0C, Reagent NPWR was compatible with reagent CMC, K-4.
REFERENCES
1. Bulatov A.I., Magazov R.R., Shamanov S.A. Influence of indexes of features of the drilling agent and their types to the speed of drilling // collection of scientific works of the scientific technical center LLC "Kubangazprom".-Krasnodar, 2001. S.92-103.
2. Theory and practice of well completion. Bulatov A.I., Makarenko P.P., Budnikov V.F., and others. V 5t.-M.:1997.T.1.S.29-4, T.2.S.60-90.
3. Roger V.F. Washing fluids for drilling oil gas wells. -M.:Statetoptechnical publishing house, 1960-234 s.
WASHING LIQUIDS WHEN OPENING PRODUCTIVE LAYER WITH ABNORMALLY HIGH PORE PRESSURE
Umedov Sh. X., Akramov B. Sh., Egamberdiev B. Sh., Gapporov J. B.
Tashkent State Technical University
Opening layer with abnormally high pore pressure (AVPD) is in most cases connected with intensive oil-gas and water showings, which bring out gas ejection-fountain. Fasten borehole in condition abnormally high pore pressure not less, in a complicated way, than drilling this horizon. Often happens annulus oil and gas showings after cementing. These phenomenon specialists are explains differently.
In recent years in oil and gas regions Uzbekistan, particularly in Bukhara - Khiva, Surkhandarya and Fergana oil and gas areas are accepted measures on improvement of technologies of the opening, drilling layer with AVPD and their fastening. Designed technology of the drilling high-permeability reef of the formation with AVPD on mode, close to balanced, in system layer-borehole on methods two drilling fluids. The new reagents are used for processing drilling fluids with high density.
The special field researches are conducted for determination parameter and mode priming drilling fluids for each borehole for the reason ensuring the normal opening layer.
Opening and drilling productive horizon on AVPD is realized with drilling mud heaver. Density washing liquids varies within 1,6 - 2,25 g/sm2. The preparation such drilling fluids with rheological and technological characteristics, meeting the demands technologies of the drilling in complex condition, presents the significant difficulties, but maintenance their parameter in process of the drilling else more complicated. The difficulty of the regulation characteristic washing liquids with high density is concluded in that contents dispersed phases in drilling fluids is reached greater values and accordingly decreases the amount of the dispersion ambience.
To get drilling fluids with high density is added weighting additive - barite, sometimes hematite or magnetite. There are different compositions of washing liquids, which applicable for drilling on area with AVPD.
The principle scheme of the preparation drilling fluids with density 1,60 g/sm3 are above concluded in following:
Prepares bentonitic liquid mud with density 1,15-1,30 g/sm3 on water base, which is processed reagent - fluid loss reducer (stabilizer), but then reagent-viscosity reducer (structured-mechanical characteristic). Hereinafter, in this drilling fluid added accounting amount weighing agent, and carefully mixed in special mechanical or hydraulic mixer. If it is required, coming from analysis characteristic of weighted drilling mud, in addition added reagents.
At initial period launching of technology of the drilling with using weighted drilling mud were used well known in that years reagents: USCHR (lignin-alkaline agent), CMC-300 (carboxymethyl cellulose), CMC-600, CSSB (condensed sulfite-cellulose liquor), caustic soda and others some of these reagents have simultaneously played the role of the stabilizer and viscosity reducer. As fermenters were used formalin, caustic soda, in the capacity of antifoam agents - NCHK (neutralized black contact), soap stock, for the reason warning tightening and stuck drilling pipe were used oil. These additives were used for reduction static and dynamic stress of the shift of the drilling fluids, which promoted the reduction of the hydraulic resistances. With using specified reagent are drilled boreholes with AVPD in Fergana and Surkhandarya oil and gas areas.
In recent years high-effective thermobaric-safely chemical reagent appeared in arsenal drillers for regulation structured-mechanical characteristic drilling mud heaver and vastly changed technology of their preparation. In connection with appearance different reagent is designed amount composition of drilling fluid on base all possible combination these reagents.
In Uzbekistan are widely used:
1) Stabilizers: modified CMC-900, carbafen, reagents on polyacrylonitrile base (K-4, K-9, hypan and others), CSSB, modified starch, and others;
2) Viscosity reducers: USCHR, nitrolignin, sunil, aksel, titanium, chlorolignin and others.
For increasing thermostability of drilling fluids is used bichromate.
The preparation washing liquids by density more than 2,0 g/sm3 and regulation its characteristic much in a complicated way, in particularly, in condition of the aggressions polyvalent cation. The decision of this complex problem concerned with the laboratory of washing liquids TASHGTU and JC «IGIRNIGM». The studied characteristics of reagent and their influence upon regulations characteristic drilling mud heaver.
Compositions of drilling fluid are recommended as a result of these studies for drilling the boreholes in condition AVPD. By that low-grade barite, which contains more than 2 % clay admixtures, impossible get the drilling fluid by density above 2,0 g/sm3 with satisfactory technological feature. It is counted that if enlarge density of the barite on 0,1 g/sm3 then for reception of the drilling fluid of the same density consumption decreases on 1,5%. At density of the barite 4,3 g/sm3 on ^ drilling fluid its consumption on 32-34 kgs less, than at density 4,2 g/sm3 with the result that falls the contents of the hard phase in drilling fluid.
In laboratory studied the possibility of the joint use the magnetite with barite for making heavier drilling fluid.
The installed regularities of their influence upon characteristic of the drilling fluid that has allowed for the first time in Republic to use the mixture of the barite with magnetite for making heavier, since magnetite, possessing obviously expressed magnetic characteristic, because of orientation of the particles its dipoles must create the additional structure in high-mineralized drilling fluid and sharply enlarges stability.
The results of the learning show that plastic viscosity of the drilling fluid falls with increase the contents of the magnetite. This, obviously, is caused by reduction amount hard phase in unit of the volume because of significant greater specific gravity of the magnetite in contrast with barite. Such fact has principle importance at development high-mobility weighted drilling mud for opening subsalt productive carbonate deposit with AVPD.
At correlation of the barite with magnetite 1:1 static stress of the drilling agent sharply falls that as it was indicated above, it is important when drilling highly-permeability gas horizon.
Increase the mobility of the drilling agent with growing of the concentrations of the magnetite is explained by formation solvate shell on the end of the most act of concentration charge small part of the magnetite, which in determined degree must prevent their rapprochement, and hereunder create the certain condition for mobility such high weighted drilling mud.
At regulation characteristics of weighted drilling mud is important role plays the contents of the clay in them.
M.N. Turapov's researches have shown that at defect of the clayey phase in weighted drilling mud begins sedimentation particles, with increasing of the temperature particularly.
Aside from this, in mineralized weighted drilling mud can occur the coagulation dilution, which brings separation of the phases. At excess clays, with increasing of the temperature weighted drilling mud is thickening, and at concentrations of the clayey phase in amount 17,5% the drilling fluid becomes stagnant.
However, clay capacity of drilling fluid is different by density over 2,0 g/sm3 for different clays. The optimum contents Nefteabadskoy clays in weighted drilling mud must be within 7-12%
from total volume. If contents of the clay in drilling fluid below 7%, stability sharply falls, but over 12% - a drilling fluid thickened.
In TASHGTU and JC «IGIRNIGM» is designed and recommended several compositions weighted drilling mud by density 2,20-2,25 g/sm3 on base local polymeric reagent as reducer water-loss and sunil, as reagent - thinner.
In special container practiced some compositions weighted drilling mud on well No. 4 of area
Pamuk.
The researches JC «IGIRNIGM» is recommended reagent K-4, designed by K.S.AHMEDOV and others for stabilization weighing agent saturated salt drilling fluid by density over 2,0 g/sm3. Herewith, additive K-4 is recommended for processing fresh drilling fluid-0,6 % (in dry type) from total volume, but for salty weighted drilling mud-1,2 %. When increase the contents K-4 in drilling fluid against specified importance is noted undue familiarity and SNS. Optimum contents of sunil in drilling fluid 0,5 % from total volume (in recalculation on dry material). The additive sunil more than 0,5% worsens the stability of the drilling fluid and brings fallout of the barite.
For drilling the saline thickness and opening productive carbonate deposit with AVPD on well No. 4 of area Pamuk are prepared drilling fluid. For making heavier were used barite by density 3,964,10 g/sm3 and magnetite by density 4,40-4,57 g/sm3 at correlation 1:1. The drilling fluid before injection to borehole had density 2,20-2,26 g/sm ; viscosity 110-180 s., water-loss - 4-5cm3 for 30 minutes, crust 1,5-2,0%, stability 0.
In process of the drilling, this drilling fluid answered all requirements of technology: density 2,20 g/sm3; conditional viscosity 100-180 sec.; water-loss 4-6 sm3; SNSi - 12-50 mgs/sm2; SNSi0 -24-100 mgs/sm2; crust-1,5 mm. For maintain parameter in required limit in circulating drilling fluid were entered drilling mud, K-4, soda ash, sunil and barite.
On measure of the deeply borehole were corrected density of the drilling fluid, which was reduced till 2,16 g/sm3.
The well No. 4 of area Pamuk were drilled and cased production well m140mm. In process of the test the borehole is received small influx of the gas and measured pressures of the layer, which turned out to be equal 500 atm, rather then 570 atm as it was expected originally.
With using specified drilling fluid was passed interval 2694-2999m, in which occur the strata of the salts, anhydrite, gypsum and productive carbonate deposit. When drilling with ion calcium and magnesium drilling fluid contents went up to 1350 mg/l. For reduction of the gross amount two valence ion to drilling fluid added the soda ash.
Drilling the well No. 4 of area Pamuk with using weighted drilling mud on composition JC «IGIRNIGM» on base reagent K-4, sunil, weighing agent barites - magnetite have shown the possibility its widely implementation on area with developed saliferous strata and anomalous high layer pressures.
However, when opening highly-permeability layer, very sensitive to change hydrodynamic pressures, drilling necessary in condition, close to balance in system borehole - layer, essential role play structured-mechanical characteristic and first of all, limiting static stress of the shift(SNS) of the drilling fluid. For the matter of that sunil not always provided the necessities minimum static stress of the shift so we have found new reducer SNS and viscosity weighted drilling mud, intended for opening pre-salt carbonate deposit.
The author were conducted researches of the action of the new reagent NPVR on characteristic weighing agent by barite of the drilling fluid prepared on layer water. Untilled weighted drilling mud had following factors: density - 1800 kg/m3; viscosity - 75 with; water-loss - 20 sm3/30 minutes; crust - 5 mms; sludge - 15 %.
Each portion of this type of the drilling fluid was separately processed with the reagents NPVR and CMC-900 for learning of their influence upon characteristic of the weighted drilling mud. The results are shown on fig. 1 and 2. NPVR better reduces water-loss weighted drilling mud till density 1820 kg/m3. The additive of the new reagent in amount 1 % has reduced water-loss drilling fluid from 20 sm3/30 minut till 10 sm3/30 minut. Adding CMC-900 may reduce water-loss weighted drilling mud till 10 sm3/30 minutes, only herewith follows to raise the contents these reagent in drilling fluid till 2 % that is connected with increase the consumption such deficit reagent.
The accompaniment of the barite in drilling fluid causes its thickening, since he contains in scant fews to dissolved salts different cations and admixture of the clays. Even introduction reagent does not render the influences upon viscosity. The reasons thickening consists in that adsorption characteristic of the particles of weighing compound can a number of the reagent and hereunder by itself create the systems, possessing determined structured characteristic.
Fig.l. Parameters of weighted drilling mud, prepared on base mineralized layer water
and processed by reagent CMC-900
Table 1.
Additive CMC-900, % P, 3 kg/w T, s B, sm3/30 minut K, mm 01/10, ^ pH O, %
- 1800 75 20 5 40/50 9 15
0,50 1820 80 18 4 43/54 9 14
0,75 1800 85 17 4 40/50 9 12
1,00 1800 85 14 4 43/60 9 12
1,25 1820 90 14 3 44/65 9 10
1,50 1820 90 10 3 44/65 9 5
2,00 1820 95 8 3 45/70 9 5
Fig. 2. Parameters of weighted drilling mud, prepared on base mineralized layer water
and processed by reagent NPVR
Besides, raised viscosity of the drilling fluid, processed by acrylic reagent, can be caused characteristic of this reagent. The reagents from polyacrylonitril being high-molecular, promote the compaction of the particles of the clay with the result that growing of viscosity drilling fluid is caused. So processing weighted drilling mud fluid is produced multifunction, i.e. simultaneous introduction reducer water loss and viscosity.
Designed new polymeric water-soluble reagent (NPVR) and composition washing liquids for drilling the boreholes when opening productive horizon with AVPD and realization got result allow to do the following scientific findings and practical recommendations:
WORLD SCIENCE
№ 4(4), Vol.1, December 2015 47
Revealed particularities of the influence new polymeric water-soluble reagent on characteristic drilling fluid, as fluid loss additive and stabilizer, raising their resistance to aggressive ambience, conditioned by specifics of the composition and structure of the reagent;
It is installed that when use offered polymeric reagent, fall the viscosity of the feature and as static, so and dynamic stress of the shift, bring for reduction turning moment and increase the hydraulic power, sent on borehole bottom;
Presence in new reagent indissoluble fibrous material, promotes to strengthening structures drilling fluid that raises their stability when opening productive layer with AVPD.
Table 2.
Additive, p, kg/м Т, с В, sm /30 min К, mm 01/10, öPa рН О, %
NPVR, %
- 1800 75 20 5 40/50 9 15
0,50 1820 75 17 4 43/54 9 14
0,75 1800 75 16 4 40/52 9 12
1,00 1800 70 10 3 43/60 9 10
1,25 1820 70 9 3 44/60 9 8
1,50 1820 65 8 3 44/65 9 5
2,00 1820 60 4 2 43/65 9 3
REFERENCES
1. Bulatov A.I., Magazov R.R., Shamanov S.A. Influence of indexes of features of the drilling agent and their types to the speed of drilling // collection of scientific works of the scientific technical center LLC "Kubangazprom".-Krasnodar, 2001.
2. Rakhimov A.K. Formation exposing and mounting borehole in condition abnormally high pore pressure. Tashkent. "Fan"-1980.
3. Akramov B.Sh, Umedov Sh.Kh. Oil-and-gas production handbook. Tashkent- "Fan va tekhnologiya"-2010.
ОСОБЕННОСТИ ФУНКЦИОНИРОВАНИЯ ГИДРОМЕЛИОРАТИВНЫХ СИСТЕМ В АРИДНОЙ ЗОНЕ
ЗЕМЛЕДЕЛИЯ
1Хужакулов Рустам, Засов Сергей, 3Бобокулов Фуркат
1Каршинский инженерно-экономический институт г. Карши, Узбекистан;
2Московский государственный университет природообустройства г.Москва, Россия;
3Каршинский инженерно-экономический институт г. Карши, Узбекистан
Abstract. According to the analysis of the efficiency of irrigation production in many farms Karshi steppe in this paper considers measures for their improvement. Rational irrigation in combination with measures to improve soil fertility, are the guarantors of a stable and high yield of cotton. Under this condition, not only ensured the preservation of the high productive capacity of cultivated land, but also the optimal use of irrigation water, its smallest loss in filtering groundwater. The latter, among other things, prevents the ground water level rises and, as a result, reduce the risk of salinization of irrigated areas.
Как известно, упрошенная схема определения надежности работы гидромелиоративных сооружении состоит из оценки трёх основных элементов: проектирование, строительство и эксплуатация объекта.
