WO2008100176A1

WO2008100176A1 - Method for developing hydrocarbon accumulations

Info

Publication number: WO2008100176A1
Application number: PCT/RU2007/000607
Authority: WO
Inventors: Vladislav Ivanovich Korpusov
Original assignee: Vladislav Ivanovich Korpusov
Priority date: 2007-02-12
Filing date: 2007-11-06
Publication date: 2008-08-21
Also published as: EA200800379A3; RU2342520C2; EA012022B1; EA200800379A2; RU2007105125A

Abstract

The invention relates to methods for developing hydrocarbon accumulations at any time of the production thereof. Said invention makes it possible to control hydrocarbons extraction by means of wells having a pseudo-horizontal and/or horizontal drain hole in a productive formation, to increase the oil extraction factor and to exclude the deforming process in hydrocarbon accumulations and the formation of pockets. The inventive method for developing hydrocarbon accumulations by means of production and injector wells having a horizontal or pseudo-horizontal hole, which is open in a productive formation, consists in enhancing said method by extending a casing to the end of said holes column, by cementing the totality of the casing column from the outside and by uniformly distributing a perforation along the column section situated in the area of the entire horizontal and/or pseudo-horizontal well hole or the part thereof, in producing a uniform depression or repression along the perforated section on both sides of the oil area in the casing columns of the production or injecting wells, respectively, in arranging the horizontal and/or pseudo-horizontal holes of building production or injecting wells in a parallel position to each other but across the general direction of fractures in a production formation, in extracting oil from a collector separately from a gas-condensate and a gas and in pumping therein a thermochemically prepared and gas-saturated liquid spacer, the volume of which is equal to the volume of fluid extracted therefrom at a volume rate which does not generate the fracturing of the productive formation in the oil zone and in pumping a heated gas in the collector gas zone at a temperature greater than the formation temperature. Said method can be used for continuous and cyclic production.

Description

Method of developing hydrocarbon deposits

The invention relates to the oil and mining industries and can be used at any stage of the extraction of hydrocarbons both in continuous production and cyclical.

Prototype - a method of developing hydrocarbon deposits using a production well with a horizontal wellbore (HS) in the reservoir - the reservoir has been known for more than 50 years and is generally a more efficient way [1] than developing a hydrocarbon reservoir with a producing well with a vertical wellbore (BC) in the reservoir . This is mainly due to a longer length and, consequently, a larger area of the opened reservoir, directly susceptible to depression than the area of a perforated well with a vertical well, which increases the production flow into wells with a horizontal well.

In the entire history of the use of such wells, the arrangement of horizontal wellbores has not changed, and, accordingly, the method of developing deposits using wells with a horizontal wellbore actually has permanent disadvantages. These shortcomings are visible from studies whose results are presented in [2]. These studies compare the production rates of 68 production wells with a horizontal wellbore in the reservoir, operated from January 1993 to March 1994, with the flow rates of closely located production wells with a vertical wellbore in the reservoir. This comparison showed that the oil flow rates of 57 wells with a horizontal wellbore are more than the flow rates of vertical wells l, l ÷ lb, 3 times, and at 11 wells with a horizontal well oil flow rates were less than the flow rates of wells with a vertical wellbore. That is, it is obvious both a huge debit advantage for most of the wells with a horizontal wellbore, and a wide range of variation of this advantage, and there is a significant statistical probability of getting even worse result than for wells with a vertical well in the reservoir. These results indicate the actual uncontrollability of the production of wells with a horizontal shaft, which, basically, inevitably follows from their lack of constructive arrangement.

The main disadvantages of the method with a well with a horizontal wellbore are due to the fact that the casing of a producing well with a horizontal wellbore is brought only to the beginning of the horizontal wellbore, and the horizontal well itself is an open channel in the reservoir, without the casing. Depression created through the end of the casing in such an open channel, made in porous rock

SUBSTITUTE SHEET (RULE 26) the reservoir will always fall very quickly from the beginning of the horizontal wellbore (from the end of the casing string) along the horizontal wellhead to its end. And so fast that it may be equal to zero, still far from the end of the horizontal barrel. And this is natural for a porous reservoir, since, causing an influx of production, depression is consumed and consumed to a greater extent where its value is greater, that is, at the end of the casing. And the higher the permeability of the reservoir, the sharper is the reduction of depression along the horizontal wellbore, that is, the performance of the open horizontal wellbore a priori cannot be uniform along its length.

In addition, this non-uniformity is enhanced by the anisotropy of the permeability of the reservoir in any direction, as well as the presence of cracks of various sizes and directions in the reservoirs. With intensive work of injection wells pumping a fluid-displacing oil into the reservoir, even in the absence of cracks over time (and the production process lasts dozens of years) towards the lower end of the casing of the production well with a horizontal wellbore, extensive reservoirs are formed in the reservoir .

Moreover, due to the greatest gradient of depression in the reservoir near the end of the casing of the production well with an open horizontal shaft, the process of crest formation of bottom water and the gas crater formation of the gas cap are uneven along this trunk, and if any of them breaks into the production well reduces depression, which further increases the variation of indicators of flow rates of such wells. You can also notice that the open channel of the horizontal wellbore in the reservoir is a tool that unites its most permeable areas and cracks, that is, not only does not prevent their negative influence, but also unites and enhances their negative impact, creates uneven extraction of products from the reservoir and contributes the formation of stagnant zones.

Similar drawbacks are characteristic of the use of an injection well with an open horizontal wellbore in the reservoir, as well as wells of both assignments with an open pseudo-horizontal wellbore (PGS) in the reservoir, recommended in [3], in which the casing in the well is also brought only to the beginning of the pseudo-horizontalbore in collector.

The technical task of the invention is to increase economic efficiency, increase stability and ensure the manageability of the method of development

SUBSTITUTE SHEET (RULE 26) oil reservoirs using production and injection wells with a horizontal and / or pseudo-horizontal borehole in the reservoirs, preventing the oil deposits from dissolving and preventing the formation of stagnant zones of oil, as well as improving the efficiency of gas production by wells from oil and gas deposits.

This goal is achieved by a set of improvements in several aspects of the production process by a known method: a change in the arrangement of wells with a horizontal or pseudo-horizontal trunk, as well as modes and tactics of their operation.

First, a casing string is introduced into an open horizontal or pseudo-horizontal well bore. This action is performed either immediately when the well has been drilled during the casing, the diameter of the casing in this case is kept from the mouth to the end of the bottom hole, or when the well with a horizontal or pseudo-horizontal trunk is already equipped with a cemented casing to the beginning of the horizontal or pseudo-horizontal bore, then through the volume of the existing casing pass another casing with a smaller diameter and place it from the wellhead to the end of the bottom.

Finally, when transferring from a reservoir with already equipped vertical wells to horizontal or pseudo-horizontal wells, such as further development of the reservoir or at any development time, the well is drilled above the reservoir of an installed casing with a vertical well, then a new direction of the well is drilled from it and a horizontal or pseudo-horizontal wellbore is created in the reservoir, after which a drill is drilled from the wellhead through the upper part oh casing is introduced to the end face in the horizontal or psevdogorizontalny wellbore casing of smaller diameter than the drilled.

The subsequent arrangement of the injected casing in a horizontal or pseudo-horizontal wellbore is performed identically for all three cases considered. The casing string inserted into a horizontal or pseudo-horizontal wellbore is cemented from the outside, in a tapered pipe at the end of this column, which facilitated the posting of this column along a horizontal or pseudo-horizontal wellbore, creating a cement plug, and then evenly perforating this casing in the horizontal zone

SUBSTITUTE SHEET (RULE 26) or pseudo-horizontal wellbore. Using cementing and dispersed uniform perforation of the casing creates a more even distribution of depression along a horizontal or pseudo-horizontal borehole of the production well than in a horizontal or pseudo-horizontal wellbore, but without a casing in it, and therefore more evenly extract the products from the hydrocarbon reservoir being developed , prevent a local, massive breakthrough of a fluid in any place in a well with a horizontal or pseudo horizontal even if there is a super collector or cracks.

Similarly, by cementation and dispersed uniform perforation of the casing in the injection well, the repression is distributed to the reservoir more evenly along the horizontal or pseudo-horizontal wellbore and, therefore, a thermochemically prepared gas-saturated propellant (for example, water) is injected more uniformly into the reservoir which prevents the formation of powerful local flows of the displacer and, therefore, prevents the formation of stagnant zones Manifold away from these streams.

In addition, the negative impact of fractures in the reservoir on the extraction of products and its watering reduce the thus equipped horizontal or pseudo-horizontal shafts of injection and production wells by parallel arrangement between them, but across the predominant direction of these cracks. In this case, the volume of the liquid propellant is pumped in a volume equal to the volume of the extracted fluid from the formation, with a volumetric rate of injection of the displacer that does not lead to hydraulic fracturing. All these measures prevent the dissolution of oil deposits and the formation of stagnant zones with oil in the deposits.

So, using cementing and uniform punching of casing strings in horizontal or pseudo-horizontal wells of production and injection wells, as well as with the help of depression and repression, they double control the development of deposits from both the production well and the injection well. Moreover, an even greater uniformity of production in the well along the horizontal or pseudo-horizontal bore is additionally ensured by the fact that it creates an outflow inside the casing from the opposite sides of its perforated part. To do this, inside the casing from the wellhead to the end of the column in the zone, horizontal or pseudo-horizontal

SUBSTITUTE SHEET (RULE 26) the wellbore, without touching the cement plug, enter the pipe with a cone-shaped plug at its end and holes in the wall of the end section of this pipe in front of the plug. Selection received through the perforation in the casing production is carried out through these holes in the pipe, and through the gap between this pipe and the casing in front of the perforated area, that is, support the depression from opposite sides of the perforated area.,

In a corresponding way, repressing the reservoir from both sides of the casing perforation section in the zone of a horizontal or pseudo-horizontal wellbore is supported by the same pipe inserted into the casing in the injection well, which additionally ensures that the displacement fluid is evenly distributed along the horizontal or pseudo horizontal well bore. To increase or maintain the temperature of the displacer injected into the reservoir above the reservoir temperature, as well as raising the temperature of the products produced above the reservoir, a heater is introduced into the pipe from the wellhead to the holes in the pipe, thereby increasing reservoir energy and preventing an increase in oil viscosity in the reservoir, as well as particles of hydrates, the release of paraffin and their settling both in the pores of the reservoir and on the wall of the casing and all parts in it in the production well support or create gas ftny mode in it.

A uniform injection of a thermochemically prepared displacer and a uniform selection of products from the reservoir using wells with a horizontal or pseudo-horizontal bore, equipped with casing strings, which are equipped with an additional pipe and heater in the zone of a horizontal or pseudo-horizontal borehole, create conditions for increasing flow rate and oil recovery factor (CIN) from the collector, since this uniformity increases as the coverage ratio (K _ox ) by displacing output from the volume of the collector This prevents the formation of stagnant zones, as well as increases the coefficient of displacement (K _in ). of oil from the pores of the collector, treated thermochemically prepared displacer (micro-level), and the product of these coefficients, according to the formula of academician A.P. Krylov [3] is equal to CIN:

KИH = K _oXB - K _in , therefore, the proposed method for the development of hydrocarbon deposits increases the CIN from the reservoir in any energy regime of the reservoir development, as in continuous production, pelvis and cyclic.

SUBSTITUTE SHEET (RULE 26) For separate, enhanced gas extraction with condensate from oil, production and injection wells are used, equipped with a sectional column introduced from the wellhead to the end of the bottomhole, made in the form of a pseudo-horizontal wellbore in the gas zone of the reservoir, turning into a horizontal wellbore in the oil zone of the reservoir. The section in the pseudo-horizontal barrel produces gas with condensate, and the section extracts oil in the horizontal wellbore and, respectively, separately, gas and saturated thermochemically prepared displacer (for example, water) are injected into injection zones in different reservoir zones.

The arrangement of sectional production and injection casing from the non-section considered is different in that in the area of the pseudo-horizontal wellbore between the pipe inserted to the end of the face and the casing column there is a shortened pipe between which the packer and the casing set the packer in the pseudo-horizontal trunk than in the section of the casing and between the casing and between the casing and the casing column. into two sections.

Thus, in the claimed method of developing hydrocarbon deposits, the solution of the stated technical problem is carried out by an effective dual control of the extraction of products: both a production and an injection well. At the same time, in a well under construction with a horizontal or pseudo-horizontal barrel or already constructed, but with a casing installed only before the beginning of the horizontal or pseudo-horizontal trunk ^ or into a well with a vertical well in the reservoir, which is converted into a well with a horizontal or pseudo horizontal trunk, either production or injection well, from the mouth enter the casing for the entire length of the well. The arrangement of the sectional casing in the pseudo-horizontal and horizontal wellbore zone is shown in the drawing: at the end of this string 1 a tapering nozzle 2 is installed, the entire casing string is cemented outside and a cement plug 3 is created in the narrowing nozzle, and the casing string is evenly punched in the horizontal section of the horizontal wellbore located in the oil well the reservoir zone, and parts of the pseudo-horizontal wellbore located in the gas zone of the reservoir, and inside the casing from the wellhead to the cement plug, without touching it, introducing a pipe 4 with a cone-shaped plug 5 and holes 6 in front of it in the wall of this pipe, and a packer 8 is placed between the other, shortened pipe 7 and casing string. A depression is created in the production well and, accordingly, repression in the injection well from two sides of the casing perforated columns in the zone of a horizontal wellbore and from the mouth - in the zone of a pseudo-horizontal wellbore; inside the smaller diameter of the pipe from

SUBSTITUTE SHEET (RULE 26) wellhead to the holes in the pipe enter the heater 9; Pipes 4 and 7 in the casing are fixed with hydraulic anchors 10, and the coaxiality between the casing and the pipes in the zone of the horizontal and pseudo-horizontal bore, if necessary, is maintained, for example, by means of support rings 11 with cone-shaped openings for the passage of pipes and openings for the passage of fluids. The number and size of the perforation holes in the column, as well as the uniform depression created in the production well and uniform repression in the injection well, double control production of oil and oil, and the location of horizontal and / or pseudo-horizontal wells of the production wells parallel to the corresponding injection well stems, but across the preferred direction fractures in the reservoir ensure the reliability and stability of the realization of the advantages of this dual control, which creates words to increase the CIN and to reduce the number of wells in the hydrocarbon deposit being developed.

Information sources:

1. Grigoryan A.M .: Multi-well and horizontal wells. M., Nedra, 1969, - 190 p.

2. Heads L.B., Volkov CH. : The state of construction and operation of horizontal wells in Russia. || Oil Khoz., Na 7, 1995, p. 23-26.

3. Zakirov C.H., Zakirov E.C., Zakirov I.C., Batanova M.H., Spiridonov A..B.: New Principles and Technologies for the Development of Oil and Gas Fields, M., RAS IPNG, 2004. p. 346-355, p. 35

SUBSTITUTE SHEET (RULE 26)

Claims

Formula of invention

1. A method for the development of hydrocarbon deposits using well production having a reservoir - a horizontal collector or psevdogorizontalny barrel, which is introduced before the start of and outside the casing is cemented, after which an end to _/ from a free casing or horizontal production well bore psevdogorizontalnom products create depression , characterized in that when casing a well, the casing is immediately injected to the end of its horizontal or pseudo-horizontal bore and only then menting outside, create at the end of the casing cement plug is perforated along the length of the casing in the zone of horizontal or psevdogorizontalnogo borehole and create a depression in the reservoir through the perforation. ;

2. The method according to p. 1, characterized in that inside the perforated casing from the mouth to the end in the zone of a horizontal or pseudo-horizontal wellbore, without touching the cement plug, insert a pipe with a plug at its end and holes on the wall of the end portion of the pipe in front of the plug with the help of which the gap between the casing and the pipe from the wellhead side creates a depression and equalizes the values of its values in the reservoir along the horizontal or pseudo-horizontal trunk of the production well, and that the injection well for pumping the energy-carrying displacer is created with a horizontal or pseudo-horizontal borehole in the reservoir, equip them with a casing string to the end of the well similarly to the casing string in the production well and pump a thermochemical, gas-saturated liquid displacer in a volume equal to the volume of the lectant, which is leaked. , and with a volumetric rate that does not lead to fracturing of the reservoir; as well as or / and the fact that they use production and injection wells with a pseudo-horizontal wellbore in the reservoir, passing into a horizontal wellbore, which are equipped with sectional casing until the end of the bottomhole, and the pseudo-horizontal part of the well is located in the gas zone, and the horizontal - in the oil zone of the gas-oil reservoir and separately extract gas with condensate from oil, and, respectively, separately heated gas and gas-saturated, thermochemically prepared liquid propellant are pumped.

SUBSTITUTE SHEET (RULE 26)

3. The method according to p. 2, characterized in that the horizontal and / or pseudo-horizontal wellbore of the production and injection wells under construction are located across the preferential direction of the fractures in the reservoir, but parallel to each other and that is used both in continuous production and cyclical . ;

4. A method of developing hydrocarbon deposits by operating a well that has a horizontal or pseudo-horizontal wellbore in the reservoir - prior to the start of which a casing string is introduced and cemented outside, after the end of which, in a horizontal or pseudo-horizontal wellbore producing the production well, a depression is created in the casing-free horizontal characterized in that a smaller diameter casing is introduced through the cemented casing from the wellhead to the end of the horizontal silt psevdogorizontalnogo its bore is cemented on the outside, is formed on the end of the casing cement plug is perforated along the length of the casing in the zone of horizontal or psevdogorizontalnogo borehole and create a depression in the reservoir through the perforation.

5. The method according to p. 4, characterized in that inside the perforated casing from the mouth to the end in the zone of a horizontal or pseudo-horizontal wellbore, without touching the cement plug, insert a pipe with a plug at its end and holes on the wall of the end portion of the pipe in front of the plug , with the help of which and the gap between the casing and the pipe from the wellhead side create a depression and equalize the values of its values in the reservoir along the horizontal or pseudo-horizontal trunk of the production well; and the fact that the injection well for pumping the energy-carrying displacer is created with a horizontal or pseudo-horizontal wellbore in the reservoir, is equipped with a casing string to the end of the well and pumped a thermochemically prepared, gas-saturated liquid propellant in a volume equal to the volume of the extracted liquid from the reservoir with a producing well and a displacer in the reservoir and a wellhead. speed, not leading to hydraulic fracturing of the reservoir; as well as or / and the fact that they use production and injection wells with a pseudo-horizontal wellbore in the reservoir, passing into a horizontal wellbore, which are equipped with sectional casing until the end of the bottomhole, and the pseudo-horizontal part of the well is located in the gas zone, and the horizontal - in the oil zone of the gas-oil reservoir and separately extract gas from the

SUBSTITUTE SHEET (RULE 26) the condensate from the oil, and also, respectively, separately injected heated gas and gas-saturated thermochemically prepared liquid propellant.

6. A method of developing hydrocarbon deposits using a well that has a vertical wellbore in a reservoir - a reservoir that has been injected, cemented and perforated into a casing, which is depressed through the perforations, which are drilled above the reservoir through the casing wall. A new direction of the well and create it in the reservoir with a horizontal or pseudo-horizontal barrel, and to the end of the horizontal or pseudo-horizontal wellbore from the wellhead through the ver The lower part of the drilled casing is injected with a smaller diameter casing, cementing it outside, forming a cement plug at its end, perforating the casing along the length in the zone of a horizontal or pseudo-horizontal wellbore and creating a depression in the reservoir through this perforation.

7. The method according to p. 6, characterized in that inside the perforated casing from the mouth to the end in the zone of a horizontal or pseudo-horizontal wellbore, without touching the cement plug, insert a pipe with a plug at its end and holes on the wall of the end portion of this pipe before the plug with the help of which the gap between the casing and the pipe from the wellhead side creates a depression and equalizes the values of its values in the reservoir along the horizontal or pseudo-horizontal trunk of the production well, and that the injection well for pumping the energy-carrying displacer is created with a horizontal or pseudo-horizontal barrel in the reservoir, equip them with a casing string and pumped thermochemically prepared, gas-saturated liquid displacer in a volume equal to the volume of the extracted fluid from the reservoir with a producing well, and with a volumetric rate of body. to fracturing the reservoir; as well as or / and the fact that they use production and injection wells with a pseudo-horizontal wellbore in the reservoir, passing into a horizontal wellbore, which are equipped with sectional ones; casing strings to the end of the bottom, and the pseudo-horizontal part of the well is located in the gas zone, and the horizontal - in the oil zone of the gas-oil reservoir and gas with condensation from oil is extracted separately, and, respectively, heated gas and gas-saturated, thermochemically prepared liquid propellant are separately pumped.

8. The method according to p. 7, characterized in that the horizontal and / or pseudo-horizontal barrel of the production and injection wells under construction

SUBSTITUTE SHEET (RULE 26) have across the predominant direction of cracks in the reservoir and in parallel with each other and that is used both in continuous production of products, and cyclical.

SUBSTITUTE SHEET (RULE 26)