SU929824A1

SU929824A1 - Method of isolating water inflow into oil well

Info

Publication number: SU929824A1
Application number: SU731904852A
Authority: SU
Inventors: Евгений Васильевич Кузнецов; Ришат Тимергалеевич Булгаков; Рафхат Ахметович Максутов; Алмаз Шакирович Газизов; Юрий Васильевич Баранов; Лариса Андреевна Бударина
Original assignee: Казанский Химико-Технологический Институт Им.С.М.Кирова; Татарский Государственный Научно-Исследовательский И Проектный Институт Нефтяной Промышленности
Priority date: 1973-03-29
Filing date: 1973-03-29
Publication date: 1982-05-23

Description

Изобретение относится к нефтедобывающей промьииленности, в частности к способам изоляции притока вод в неф-: тяные скважины.The invention relates to the oil industry, in particular to methods for isolating the influx of water into oil wells.

Известен способ изоляции притока вод в нефтяную скважину, заключающий в закачке в пласт акриловых смол, коагулирующих на контакте с пластовой · водой с образованием геля [1].A known method of isolating the influx of water into an oil well, which involves injecting into the formation acrylic resins that coagulate at the contact with the formation · water to form a gel [1].

Недостаток способа заключается в том, что он не позволяет создать водоизоляционный экран большой протяженности .The disadvantage of this method is that it does not allow you to create a waterproofing screen of great length.

Известен также способ изоляции притока вод в нефтяную скважину, заключа-15 ющийся в закачке в призабойную зону закупоривающего агента - кремниевокислого натрия, способного вступать с кислотами и солями в реакцию гидролиза с образованием золя, переходящего в гель [2].There is also known a method of isolating the influx of water into an oil well, which involves injecting a plugging agent, silicic acid sodium, into the bottomhole zone, which can undergo hydrolysis with acids and salts to form a sol that becomes gel [2].

Способ недостаточно эффективен изза невысокой прочности и небольшой протяженности экрана.The method is not effective enough due to the low strength and small length of the screen.

. Цель данного изобретения - повыше- 25 ние эффективности процесса изоляции.. The purpose of this invention is to increase the efficiency of the isolation process.

Указанная цель достигается тем, что согласно способу изоляции притока вод в нефтяной скважине, заключающемуся в закачке в призабойную эону за- 30 купоривающего агента, в качестве закупоривающего агента используют реагент на основе сополимера метакриловой кислоты с ее диэтиламмониевой солью.This goal is achieved by the fact that according to the method of isolating the influx of water in an oil well, which involves injecting a plugging agent into the bottomhole aeon, a reagent based on a copolymer of methacrylic acid with its diethylammonium salt is used as a plugging agent.

При этом указанный сополимер используют с содержанием в полимере 3040 мол.% 'соли и 70-60 мол.% кислоты по исходной полимеризационной смеси.Moreover, the specified copolymer is used with a content of 3040 mol% of salt in the polymer and 70-60 mol% of acid in the initial polymerization mixture.

Указанный сополимер используют в виде водного раствора с содержанием его в количестве 5-8 вес.%.The specified copolymer is used in the form of an aqueous solution with its content in the amount of 5-8 wt.%.

Причем, водный раствор предварительно подкисляют до pH 3-4.Moreover, the aqueous solution is pre-acidified to a pH of 3-4.

Способ осуществляют следующим образом.The method is as follows.

В обводнившийся„пласт нефтяной скважины закачивают закупоривающий агент - сополимер метакриловой кислоты с ее диэтилаМмониевой’ солью общей формулы . СНг CW«, -CH -C-CHj-CC.-Ο,,.ΗξΚ· '-1/2 4 / \ ' *2.^5 ^2^5A plugging agent, a copolymer of methacrylic acid with its diethylMonium’s salt of the general formula, is pumped into the watered “oil well layer”. SNG CW ", -CH -C-CHj-CC.-Ο ,,. ΗξΚ · '-1/2 4 / \' * 2. ^ 5 ^ 2 ^ 5

СН4 CH4 -СН_а-С- 1 ·-CH _a -C- 1 X X с-он и 0 s-he and 0

Данный сополимер берут при соотношении 60-60 мол.% метакриловой кислоты к 40-30 мол.% диэтиламина (по исходной полимеризационной смеси) в виде 5-8 вес.% водных предварительно подкисленных растворов (pH 3-4). 5This copolymer is taken at a ratio of 60-60 mol.% Methacrylic acid to 40-30 mol.% Diethylamine (based on the initial polymerization mixture) in the form of 5-8 wt.% Aqueous pre-acidified solutions (pH 3-4). 5

Водный раствор с содержанием 5-8% указанного сополимера смеси имеет вязкость 3-90 сПз при плотности 1,0011,008 г/см^ -при 20°С. ЮAn aqueous solution with a content of 5-8% of the specified copolymer of the mixture has a viscosity of 3-90 cPs at a density of 1.0011.008 g / cm2 at 20 ° C. YU

П ри м е р. Фильтрацию модели нефти через.слой песчаника проводят в следующем порядке. Сначала песчаники при вакууме насыщают минерализованной водой (состав минерализованной воды В—ионах, мг/л: Са±¹“ 24713; С1 .5171947,НСОэ = 7,32, Мд** = 4521, Na* х К^- 74589 (в пересчете на Na), после чего через слой гГесчаника проводят фильтрацию 5%. раствора сополимера состава 60% кислоты и 40% соли < до установления постоянной скорости фильтрации . Выдерживают образец в течение трех ч. дл'Я полного выделения экранирующего осадка', и проводят фильт-$ рацию модели нефти. В качестве модели нефти берут дегазированную нефть, разбавленную керосином.EXAMPLE The oil model is filtered through a sandstone layer in the following order. First, the sandstones are saturated with mineralized water under vacuum (the composition of the mineralized water is B-ions, mg / l: Ca ± ¹ “24713; C1 .5171947, НСОе = 7.32, Md ** = 4521, Na * x K ^- 74589 (in terms of on Na), after which a 5% solution of a copolymer of 60% acid and 40% salt <is filtered through a geschanik layer until a constant filtration rate is established. The sample is held for three hours to 'fully isolate the screening precipitate' and filter - Two-way radio of the oil model: degassed oil diluted with kerosene is taken as the oil model.

Объемная скорость фильтрации модели нефти через образец песчаника, обработанный данным сополимером (при установлении стационарного режима фильтрации) равна 28 см³/мин, в то время, как объемная скорость фильтрации модели нефти через необработанный песчаник равна 13,8 см?/мин, т.е. проницаемость песчаника по нефти увеличивается в 2 раза. Проницаемость по минерализованной воде после обработки его данным сополимером снижается до 6-7 раз.The volumetric rate of filtration of the oil model through a sandstone sample treated with this copolymer (when establishing a stationary filtration mode) is 28 cm ³ / min, while the volumetric rate of filtration of the oil model through the raw sandstone is 13.8 cm? / Min, t. e. sandstone permeability to oil increases by 2 times. The mineral water permeability after treatment with this copolymer is reduced to 6-7 times.

3$3 $

Предлагаемый способ позволяет обеспечить надежную селективную изоляцию водонасыщенных горизонтов и увеличить нефтеотдачу пластов.The proposed method allows for reliable selective isolation of water-saturated horizons and increase oil recovery.

Claims

The invention relates to oil producing industry, to carry it, in particular to methods for isolating water inflow into oil wells. There is a method for isolating the inflow of water into an oil well, concluded 1 (injection into the reservoir of acrylic resins that coagulate on contact with the formation water to form gel 1. The disadvantage of this method is that it does not allow to create a water insulating screen It is also known to isolate, when a stream of water flows, into an oil squash, which consists in pumping a clogging agent, silicate acid, capable of reacting with acids and salts into the hydrolysis reaction with the formation of sol, passing gel 2. The method is not effective enough because of its low strength and small screen length .. The purpose of the present invention is to increase the efficiency of the isolation process. This goal is achieved by the method of isolating water inflow in an oil well, involving injection into the wellbore the zone of the blocking agent, as a procurement for the I1vak tse agent, use a reagent based on a copolymer of methacrylic acid with its diethylammonium salt. Moreover, the specified copolymer is used with the content in the polymer of 3040 mol.% Salt and 70-60 mol.% Acid in the initial polymerization mixture. The specified copolymer is used in the form of an aqueous solution with its content in the amount of 5-8 wt.%. Moreover, the aqueous solution is preacidified to a pH of 3-4. The method is carried out by the next sample. A blocked agent, methacrylic acid copolymer with its diethylammonium salt of general formula / h, is pumped into the flooded reservoir of the oil well. This copolymer is taken at a ratio of 60–60 mass% of methacrylic acid to 40–30 mol% of diethylamine (based on the initial polymerization mixture) in the form of 5–8% by weight of aqueous preacidified solutions (pH 3–4). An aqueous solution with a content of 5–8% of the indicated copolymer of the mixture has a viscosity of 3–90 cP at a density of 1.0011, 008 g / cm-at 20 ° C. N me The filtration of the oil model through the sandstone layer is carried out in the following order. At first, sandstones under vacuum are saturated with saline water (the composition of saline water in ions, mg / l: 24713; C1.5171947, HNCO3.32, MoH "- 4521, Na:; К 74589 (in terms of Na), then through the layer the sandglass was filtered by 5.%, a solution of a copolymer of composition 60% acid and 40% salt until a constant filtration rate was established. They were held for three hours to complete the screening shank, and the oil model B was filtered as a model of oil, take degassed oil diluted with kerosene. Volumetric filtration rate The model of oil through the sandstone sample processed by this copolymer (when establishing a stationary filtration mode) is 28, while the volumetric rate of filtration of the model of oil through untreated sandstone is 13.8, i.e., the permeability of sandstone in oil increases by 2 times. after treatment with this copolymer, in terms of saline water is reduced to 6-7 times. The proposed method allows to provide reliable selective isolation of water-saturated horizons and increase oil recovery. Claim 1. A method for isolating the flow of water into an oil well, which involves injecting a sealing agent into the bottomhole zone, characterized in that, in order to improve the efficiency of the isolation process, a copolymer of methacrylic acid with its diethylammonium acid is used as a sealing agent. with salt. 2. Method POP1, characterized in that a methacrylic acid copolymer with its diethylammonium salt is used as a reagent with a polymer content of 30 to 40 mol% salt and 60–70 mol% acid from the initial polymerization mixture. 3. Method according to Claims 1 and 2, characterized in that the reagent based on a copolymer of methacrylic acid with its diethylammonium salt is used in the form of an aqueous solution with an amount of 9-8 wt.%. 4. The method according to paragraphs. 1-3, characterized in that the aqueous solution of a copolymer of methacrylic acid with its ethyl ammonium salt is pre-acidified to pH 3-4. Sources of information taken into account in the examination 1. US patent number 2670048, cl. 166-22, published, 1954.

2. US patent 3,244,230, cl. 166-30, published. 1966 (prototype).