(57) Abstract:The invention relates to the oil industry, in particular to the foamable compositions of the three-phase foams for use as drilling fluids under conditions of abnormally low formation pressure during the primary opening of the productive deposits of oil, gas and capital repair of wells. The technical result is to increase foam stability by reducing the filter and improve the structural performance of the structure with the formation of the condensed acid-soluble colloids as a solid phase three-phase foam. Foamable composition, including fresh water, foaming agent, stabilizer and seed, as a foam stabilizer contains modified starch, alfacell, and as the seed - chalk technical, the composition additionally contains alumoxane and soda ash in the following ratio, wt.%: the foaming agent 0,8-1,8; modified starch 5,0-7,0; alfacell 0.18 to 0.3; the chalk technical 3,0-4,0; alumoxane 1.1 to 1.4; soda ash 0,6-0,8; fresh water - the rest. table 1. The invention relates to the oil and gas industry, casinosplay abnormally low formation pressure (anpd) during the primary opening of the productive deposits of oil, gas and capital repair of wells.Known foamable composition containing the foaming agent (sulfonic acid) 1.5 wt.%, stabilizer (CMC) of 1.0 wt.%, bentonite 20.0 wt.% and water /1/.Known composition does not provide the necessary stability (life) three phase pins and leads to damage to the productive formations due to difficult-to-remove clogging the pore channels of the clay particles.Closest to the claimed on purpose and essential features is a foamable composition for killing wells containing fresh water, a foaming agent, bentonite, polyacrylamide as a foam stabilizer and condensed sulfite-alcohol bard (kssb-4) in the following ratio of ingredients, wt.%: /2/
The foaming agent - 1,0-3,0
Bentonite - 1,0-3,0
Polyacrylamide - 0,5-0,7
Condensed sulfite - alcohol bard (kssb-4) - 5,0-8,0
Fresh water - the Rest
However, the known foamable composition does not provide long-term stability of the foam due to poor structural performance and high filtration. In addition, the presence of bentonite in the composition leads to clogging of the pores of the layer of clay castengera filtering and improvement of the structural performance of the structure with the formation of the condensed acid-soluble colloids as a solid phase three-phase foam.To solve this problem the inventive foamable composition containing fresh water, a foaming agent, a foam stabilizer and a seed crystal, as a foam stabilizer contains modified starch, alfacell, and as the seed - technical chalk, the composition additionally contains alumoxane and soda ash in the following ratio, wt.%:
The foaming agent - 0,8-1,8
Modified starch - 5,0-7,0
Alfacell - 0.18 to 0.3 to
Chalk technical - 3,0-4,0
Alumoxane - 1,1-1,4
Soda ash - 0,6-0,8
Fresh water - the Rest
Foamable composition is a colloid-polymer solution with a condensed acid-soluble colloids Hydrosol aluminum. The formation of condensed colloids produced when the reaction
< / BR>The difference of the foaming composition is used as a stabilizer - modified starch and salvatella, as the seed - technical chalk and supplementation in the composition of aluminum chloride and soda ash in the claimed proportions of ingredients.Technical chalk is a white powder or white-with the duty to regulate the suspension. Produced by enterprises of the construction industry and widely used in everyday life, industry, drilling /3/.Alumoxane is a transparent liquid containing 20-25 wt. % basic substance or powder light yellow or greenish color with a faint smell of hydrochloric acid, environmentally safe. Alumoxane produced at JSC "Salavatnefteorgsintez", JSC "caustic" ,Sterlitamak, is a by-product of the processes of petrochemical synthesis. You know its application in the technology of water purification and composition of drilling fluids, grouting cement /4, 5/.As a result of joint use of aluminum chloride and chalk when reaching a pH of 4.35 is the formation of condensed colloids Hydrosol aluminum with a particle size of 410-6m able to create a gel structure. Condensed colloids Hydrosol aluminum exist in the form of a solid phase in the range of pH of 4.35-10,5 that promotes their dissolution in the composition of the mud cake on the wall of the wellbore and allows you to restore the permeability of the productive reservoir.Modified starch is a white powder or yellowish color, which is good restoreposition modified starch as a reagent to reduce the filter and improve the structural properties of drilling muds /6, 7/.Alfacell - water-soluble gidroxiatilzelluloza, is a yellowish-white the product is readily soluble in water. Alfacell comes in the form of granules or powder JSC polycell".Know the use of alfacell to reduce filtration of drilling and grouting mortars /8, 9/.The use of modified starch strengthens structural adsorption layers by stitching molecules, increasing the resistance of the foam.Joint use of modified starch and alfacell as foam stabilizer composition authors not identified.Sharing in the inventive composition modified starch and alfacell helps to ensure low values of the filter and increase structural indicators foaming composition due to the fact that, penetrating between the colloidal particles of gel stabilizers take water from the system, strengthening the connection of the structural lattice. This ensures long-term retention of particles of condensed solid phase (gel) in suspension, thereby increasing the stability of the foam. Use as a stabilizer of one of the modified crashed starch to achieve low values is impractical. When used as a stabilizer of one alfacell achieved only low values of the filter, and structural indicators are not improving.Soda ash is a white crystalline powder density of 2.5 g/cm3. Aqueous solutions are alkaline reaction.It is known the use of soda ash in chemical, glass, soap, paper, textile industries, drilling /10, 11/.Use in the inventive composition of soda ash provides a reduction in ionic strength of the medium obtained colloidal solution by binding of calcium ions in the composition, which leads to the formation of more fine-dispersed solid phase, obtaining low values and long-term stability of the foam.The authors experimentally found that giving foaming composition low filtration and high structural indices to obtain long-term stable foam was made possible through a complex use of ingredients in the inventive composition in their new relationship. Originally, the interaction of the aqueous solution of aluminum chloride with chalk is formed of condensed solid phase (helstone, it helps to improve the action of the stabilizers. Molecules create a foaming agent in the liquid films between the gas bubbles mechanically strong adsorbtsionnyi layer with a low surface tension, providing long-term stability of the foam.Achieved by carrying out the invention the technical result is to achieve high resilience foam and the possibility of its use as a drilling fluid under conditions of abnormally low. Due to the low filtering and kislotorastvorimuu solid phase allows you to resolutely pore channels during mastering, thereby increasing the permeability of the productive formation after exposure to the claimed composition.The claimed technical solution integrated use of distinctive features allows to solve the new technical problem: increase foam stability by reducing the filter and improve the structural performance of the structure, which allows to make a conclusion on the conformity of the proposed technical solution the criterion of "inventive step"
The structure of the prototype is prepared as follows.Example 1.Take 853 g of fresh water. In 353 g of water in the swelling. In the prepared solution of bentonite added 30 g of the foaming agent OP-10, then 80 g kssb-4 and the solution thoroughly mixed. Then this solution is injected prepared solution of PAA and mixed until a homogeneous composition. The parameters of the obtained foam of the following composition: density - 758 kg/m3filtering - 2410-6m3/30 min, SNC - 0.8 PA, SNA1to 0.9 PA, SNA24to 0.9, the ratio is 2, the resistance is 0.15 d/cm3(experiment 3).Similarly prepare the inventive foamable composition.The technological parameters of the structures define the default devices by known techniques /12/.The ratio of the foam is determined by the ratio of volume of foam foaming composition to the volume newspring foaming composition. Sustainability is the ability of the foamed composition to maintain the original volume. The criterion for estimating the stability of the foam is the lifetime of the liquid film between the gas bubbles.When conducting laboratory studies were used:
as the foaming agent - OP-10 GOST 8433-81 (surfactant nonionic type), sulfinol on THE 6-01-862-73 (anionic surfactant is BR> as the seed - technical chalk GOST 17498-72;
- alumoxane on THE 6-01-00203312-160-95, , Sterlitamak and THE 38.3021-63-89 JSC "Salavatnefteorgsintez";
- soda ash according to GOST 5100-85;
technical water hardness 12 mg EQ/lExample 2.For the preparation of foamable composition in 867,5 g fresh water is introduced 40 g technical chalk, mix in lopasni stirrer for 10 minutes, add 11 g (in terms of dry substance) of aluminum chloride (concentration of 25 wt.%), mix to obtain a colloidal solution. In the prepared solution with stirring, add 6 g of sodium carbonate, stirred for 10 minutes, and then add 60 g of modified starch, 2.5 g of alfacell and stirred until complete dissolution of the stabilizers, then add 13 g of OP-10 (neonol or more nonionic surfactants). Produce foaming in a paddle stirrer for 30 minutes to form a constant volume of the foam and define the indicators of the composition. The technological parameters of the following composition:
P=580 kg/m3CHC=9,2 PA, SNA1=10,8 PA, SNA24=10,9 PA, f= 0,510-6m3/30min, K=5, the resistance 12 days./cm3(experiment 9).Similarly prepared compositions at different is ablity showed what foamable composition of the prototype has multiplicity equal to 2-5, high density P=756-924 kg/m3low static shear stress in time SNA=0.4 to 0.8 PA, SNA1= 0,4-0,9 PA, SNA24= 0,4-0,9 PA and high filtration performance f= 2410-6-3610-6kg/m3that results in unstable foam (experiments 1-4).Offer foamable composition containing components in the claimed range when the ratio of from 4 to 10 and a density of from 430 to 632 kg/m3has low values of filtrated from 0.5 to 2,510-6m3/30 min and high performance of the static shear stress SNA=7,8-15,4 PA, SNA1=8,0-16,4 PA, SNA24=8-16,6 PA (experiments 5-15), which promotes long-term sustainability of fine foam from 3 to 20 days/cm3. The content in the foam composition of chalk within 3-4 wt.% and aluminum chloride in the range from 1.1 to 1.4 wt.% is optimal (experiments 5-15).The content in the composition of chalk more than 4 wt.% and aluminum chloride more than 1.4 wt.% it is not economically feasible (experiments 16, 17), as a larger improvement is not observed.The content in the composition of chalk less than 3 wt.% and aluminum chloride less than 1.1 wt.% does not allow to achieve the project objectives centuryThe content of the modified starch 5-7 wt.% and alfacell 0.18 to 0.3 wt. % is optimal. The content of the modified starch is less than 5 wt.% and alfacell less than 0.18 wt.% leads to high values (experiments 20, 21) that does not provide long-term stability of the foam. The content of more than 7 wt.% starch and more than 0.3 wt.% alfacell impractical (experiments 22, 23), since low values of filter to obtain stable foams have already been achieved.The content of the soda ash 0,6-0,8 wt. % in the inventive composition is optimal for complete binding of calcium ions in the composition, preventing low filtering. The content in the composition is less than 0.6 wt.% soda ash is not possible to obtain a stable foam due to the high values foamable composition as calcium ions in the solution is completely unrelated (experiments 18, 19). The content of the soda ash more than 0.8 wt.% impractical because all the calcium ions are achieved values of the filter, providing a stable foam (experiments 16, 17).The content of the foaming agent in the range of 0.8-1.8 wt.% is optimal (experiments 5-15). At a lower content of surfactant is not ensured high wspanialy what I foamable composition is not observed, it occurs only unnecessary wastage of reagents (experiments 16, 17). As surfactants along with OP-10 and the sulfonic acid can be used other nonionic or anionic surfactant or a mixture thereof. Thus, the inventive composition has a significantly better filtration and structural indicators, providing long-term stability of the foam.The proposed solution allows to obtain long-term stable three-phase foam-based polymer-colloid foaming composition in which the solid clay phase is replaced by the acid-soluble condensed solid phase (gel) and ensures recovery of productivity collectors standard methods of intensification during the development wells. The use of long-term sustainable pins during drilling is more efficient than drilling fluids and provides:
- the safety of drilling operations by creating a regulatory crackdown on the reservoir;
- maintaining the permeability of rocks by creating durable colmatage screen panagulias composition;
the best indicators of mining bits by increasing the efficiency of removal of sludge, treatment of the face;
- urgent samples is osenia when repaired, etc.SOURCES OF INFORMATION TAKEN INTO ACCOUNT WHEN MAKING AN APPLICATION FOR AN INVENTION
1. Amen Century A. and others "Dissection and exploration of oil and gas reservoirs", M, "Nedra", 1980, S. 114-119, 310-316.2. A. C. the USSR N1208192,4 MCI E 21B 33/138, B. I. N 4, 1986 (prototype).3. Chalk technical GOST 17498-72.4. Alumoxane THE 38.302163-89.5. RF patent N2135542 6 IPC 09 To 7/02, B. I. N 24, 1999.6. Ryazanov, J. A., "Handbook of mud", Moscow., "Nedra", 1979, 82.7. GOST 7698-93.8. . Penkov A. I. and other "Stabilization of drilling mud by salvatella when testing wells in the conditions of polymineral aggression, PH, a series of "Drilling", M, VNIIEM, N12, 1981.9. RF patent N2136843, 6 IPC E 21B 33/138, B. I. N 25, 1999.10. GOST 5100-85.11. A. I. Busev, I. P. Efimov. "The dictionary of chemical terms", publishing house "Education", Moscow, 1971, S. 154.12. RD 39-2-645-81. Foamable composition containing fresh water, foaming agent, stabilizer and seed, characterized in that as a foam stabilizer, it contains modified starch, alfacell, and as the seed - chalk technical, the composition additionally contains alumoxane and soda ash the next time when cell - 0,18-0,3
Chalk technical - 3,0-4,0
Alumoxane - 1,1-1,4
Soda ash - 0,6-0,8
Fresh water - Ostalnoe
FIELD: oil and gas production.
SUBSTANCE: solid foaming agent containing, wt %: carboxymethylcellulose 15-25, sodium sec-alkyl sulfate 5-15 and sodium sulfonate 25-35 (both anionic surfactants), additionally contains: sodium silicate 3-7, sodium carbonate 2-4, disodium ethylenediaminetetraacetate as complexone 1-3, and foaming-enhancing detergent - the rest.
EFFECT: increased efficiency in carrying over formation fluid from bottom of gas and gas condensate wells.
FIELD: oil and gas production.
SUBSTANCE: invention relates to solid foaming agent for carrying over formation fluid from gas well and water/condensate mixture from gas condensate well. Solid foaming agent containing, wt %: carboxymethylcellulose 40.0-50.0, sodium sec-alkyl sulfate 35.0-45.0, and sodium sulfonate as anionic surfactant 25-35 additionally contains: disodium ethylenediaminetetraacetate as complexone 3.0-7,0, sodium carbonate as pH stabilizer 3.0-7.0, and foaming-enhancing detergent - the rest.
EFFECT: improved fluid-carrying ability.
FIELD: oil and gas production industry, in particular two-phase foam forming composition for secondary development of clay grouted stratum with non-uniform permeability by perforation under abnormal law stratum pressure.
SUBSTANCE: claimed composition contains foam forming agent, inhibitor, solvent and water. Bone glue in amount of 4-6 mass % is used as foam forming agent and inhibitor, sodium or potassium hydroxide in amount of 0.2-0.5 % is used as solvent, and balance: water. Composition of present invention makes it possible to produce foam with increased order, stability, inhibiting properties, low filtration factor, improved holding properties and to keep integrity of casing string and cement ring.
EFFECT: increased efficiency of secondary stratum development by perforation.
FIELD: oil and gas production industry, in particular two-phase foam forming composition for development of productive stratum under abnormal law stratum pressure.
SUBSTANCE: claimed composition contains foam forming agent, stabilizer, inhibitor, and processing water. Bone glue in amount of 3-5 mass % is used as foam forming agent, stabilizer and inhibitor, and balance: processing water. Composition of present invention makes it possible to produce foam with increased order, stability, inhibiting and geological properties, low filtration factor, improved holding properties.
EFFECT: increased efficiency of stratum development.
FIELD: gas production equipment, particularly for killing wells with reservoir pressure below hydrostatic pressure and for gas pipeline protection against water and mechanical impurities.
SUBSTANCE: method involves injecting methylcellulose used as gel-forming composition into well, wherein methylcellulose is introduced as foamed aqueous solution and density thereof may be regulated along the whole well borehole height.
EFFECT: possibility to regulate well killing liquid density along well borehole height, increased speed of well killing gel-forming composition production.