RU2368767C1 - High-viscous and heavy oil field development method with thermal action - Google Patents

Abstract

FIELD: oil industry.

SUBSTANCE: invention refers to development of oil fields, and namely to methods of thermal action on the deposit containing high-viscous oil. Method involves sinking of rows of vertical pressure and production wells, sinking of horizontal pressure wells along the rows of vertical wells, pumping of heat carrier to the horizontal wells and withdrawal of high-viscous and heavy oil from vertical production and pressure wells. Under each horizontal pressure well there drilled within the same productive bed is an additional horizontal production well for withdrawing high-viscous and heavy oil. Vertical production and pressure wells are arranged in rows in turn. From vertical production wells there withdrawn is high-viscous heavy oil till heat carrier enters them from horizontal pressure wells; after that, filling of the vertical pressure wells with heat carrier is stopped and they are transferred to production wells, and those production wells where the heat carrier entered are transferred to pressure wells. Later, when heat carrier enters from horizontal pressure wells to vertical production wells which have been transferred from pressure wells before, then vertical pressure wells are transferred to production wells, and vertical production wells are transferred to pressure wells and the cycle is repeated till bottom-hole zone of vertical and horizontal wells is completely developed.

EFFECT: enlarging the coverage of thermal action of the deposit owing to addition of movement of filtration liquid flows therein, and therefore, increasing coverage coefficients, as well as increase of the deposit production rate.

3 dwg

Description

The invention relates to the development of oil fields, in particular to methods of thermal exposure of a reservoir containing highly viscous oil.

A known method of developing a layered-zonal-heterogeneous deposits of highly viscous oil or bitumen (patent RU No. 2295030, IPC ЕВВ 43/24, published in bulletin No. 7 of 03/10/2007), including the construction of a multi-well horizontal well, supply of coolant and selection product, while productive formations and clay-poorly productive layers are determined in the reservoir, the horizontal trunk of a multi-wellhead producing horizontal well is carried out mainly along the productive formation, from this trunk additional side trunks are drilled under the clay with an aboproductive interlayer or ascending trunks with their completion above this interlayer, vertically and parallel to a multi-mouth horizontal production well, a multi-mouth horizontal injection well is constructed, from which additional lateral shafts are ascended through a clay-poorly productive interlayer, pump coolant into both wells and create a permeable zone between multi-mouth horizontal wells, after creating a permeable zone, the coolant is not supplied to the multi-well a horizontal production well and a multi-mouth horizontal production well with additional lateral shafts, select products, while the ascending shafts are drilled in the presence of clay-poorly permeable interlayers that are mature in area, and vertical wells are drilled from the surface, passing through a clay-poor-permeable interlayer and ending below the clay-well poorly productive stratum mainly in the reservoir, and vertical wells are used as a transport of a coolant supply channel above a clay-poorly productive interlayer, and for supplying products down to a multi-well production horizontal well.

The disadvantages of this method are:

- firstly, the large financial costs for the construction of multi-well horizontal wells, due to the fact that from the horizontal shafts of production and injection wells, additional side shafts are drilled;

- secondly, it is difficult to predict the selection of highly viscous oils and bitumen from producing wells, since this method is very demanding on the accuracy of well drilling, since from the constructed multi-well injection horizontal well additional side shafts are ascending through the clay-poorly permeable interlayer, and the horizontal multi-well shaft the producing horizontal well is carried out mainly along the productive formation, from this trunk additional side bores are drilled under the clay-weak inductance streaks or ascending stems with their completions above this seam.

The closest in technical essence is the method of thermal impact on the reservoir of highly viscous oil (patent RU No. 2199656, IPC ЕВВ 43/24, published in Bulletin No. 6 of 02.27.2003), including drilling of rows of vertical injection and production wells, drilling horizontal wells along the rows of vertical wells, periodically injecting coolant, such as steam, into horizontal wells and taking oil from vertical production wells, while also taking from vertical injection wells, and during the period of termination of the steam injection Ut selection from horizontal wells that are a source of steam breakthrough into vertical wells, and after the formation in the near-wellbore zone of all wells, they transfer to areal injection of a displacing agent, for example water, into vertical injection wells, while simultaneously extracting oil from the remaining wells.

The disadvantages of this method are:

- low coverage of the sections of the formation by thermal influence (one row of a horizontal well) and, as a result, low coverage and oil recovery coefficients of the highly viscous and heavy oil deposits, rapid flooding of the reservoir, as a result of cooling of the coolant and reservoir formation;

- there is no possibility of alternating injection of the displacing agent and the selection of highly viscous and heavy oil, respectively, either in vertical injection or in vertical production wells, which reduces the selection of highly viscous and heavy oil and, consequently, oil recovery.

The objective of the invention is the additional involvement in the development of areas of deposits of highly viscous and heavy oil, that is, increasing the coverage of the thermal effect of the reservoir by adding movement of the filtration fluid flows in it and, as a result, increasing the coverage coefficients, as well as increasing the oil recovery of the reservoir due to the possibility of alternating injection of coolant and the selection of high-viscosity and heavy oil, respectively, either in vertical injection, then in vertical production wells.

The problem is solved by the method of developing deposits of high-viscosity and heavy oil with thermal effects, including drilling rows of vertical injection and production wells, drilling horizontal injection wells along rows of vertical wells, pumping coolant into horizontal injection wells and selecting oil bitumen from vertical production wells.

It is new that under each horizontal injection well within the same reservoir, an additional horizontal production well is drilled, and vertical production and injection wells are arranged in rows in series, and during the period of oil extraction from vertical injection wells, the coolant is pumped into vertical production wells.

Figure 1 shows a diagram of the development of oil deposits of high viscosity and heavy oil.

Figure 2 shows the same section of the reservoir in the context when the coolant is pumped into vertical injection wells and the selection of high-viscosity and heavy oil from vertical production wells.

Figure 3 shows the same section of the reservoir in the context when the coolant is pumped into vertical production wells and the selection of high-viscosity and heavy oil from vertical injection wells.

The essence of the method is as follows.

The development of reservoir 1 of high viscosity and heavy oil (see Fig. 1) begins with the drilling and construction of rows of vertical producing 2, 2 ', 2'', ... 2 ⁿ and injection 3, 3', 3 '', ... 3 ⁿ wells, which are placed alternately (see figures 1 and 2) between each other and open the reservoir in its entire thickness. Between the rows of alternating vertical production wells 2, 2 ', 2'', ... 2 ⁿ and injection wells 3, 3', 3 '', ... 3 ⁿ (at the estimated distance from the condition of the greatest coverage by subsequent heat exposure), they drill and build in within the same reservoir, rows 4 and 5 of horizontal wells 6 ', 6'', ... 6 ⁿ and 7, 7', 7 '', ... 7 ⁿ (see figures 1, 2), and the upper row 4 is a number of horizontal injection wells 6, 6 ', 6'', ... 6 ⁿ , and the bottom row 5 is a series of horizontal production wells 7, 7', 7 '', ... 7 ⁿ . A row of 4 injection horizontal wells 6, 6 ', 6'', ... 6 ^{n is} located in reservoir 1 above a row of 5 horizontal production wells 7, 7', 7 '', ... 7 ⁿ .

Upon completion of drilling and construction (as shown in FIGS. 1, 2) and arrangement of all wells with pumping equipment (not shown in FIGS. 1, 2), coolant (steam, hot water, gas) is pumped into horizontal injection wells 6, 6 ' , 6 '' of row 4. The coolant, having reached reservoir 1, begins to heat up highly viscous and heavy oil (oil bitumen). As a result of heating, oil bitumen is liquefied, that is, its viscosity decreases, and when heated, oil bitumen flows through a filter (not shown) into horizontal producing wells 7, 7 ', 7'', ... 7 ^{n of} row 5, from which oil bitumen is subsequently selected , as well as heated oil bitumen, goes to the bottom of vertical producing 2, 2 ', 2'', ... 2 ⁿ and injection 3, 3', 3 '', ... 3 ⁿ wells.

At the same time, vertical injection wells 3, 3 ', 3'', ... 3 ^{n are} launched to pump the displacing agent, and vertical production wells 2, 2', 2 '', ... 2 ⁿ are launched to select heated oil bitumen.

The selection of oil bitumen from vertical production wells 2, 2 ', 2'', ... 2 ^{n is} carried out until the coolant breaks out from the horizontal injection wells 6', 6 '', ... 6 ^{n of the} upper row 4. Then, the coolant is pumped into vertical injection wells 3, 3 ', 3'', ... 3 ⁿ stop, equip them with a pump and put into operation as production, and those vertical production wells 2, 2', 2 '', ... 2 ⁿ , into which the coolant broke, are converted into injection , that is, the pumps are removed from them and put into the coolant injection, while the operation of the supercharger GOVERNMENTAL horizontal holes 6, 6 ', 6'', ... 6 ⁿ and extracting horizontal holes 7, 7', 7 '', ... 7 ⁿ rows 4 and 5, respectively continue in the same mode, i.e. carried download heat medium (steam, hot water, gas) to the injection wells 6, 6 ', 6'', comprising row 4, with the simultaneous extraction of oil bitumen through filters (not shown) of horizontal producing wells 7, 7', 7 '', ... 7 ^{n of} row 5.

In the future, when the coolant breaks out from the horizontal injection wells 6 ', 6'', ... 6 ^{n of the} upper row 4 into the vertical production wells (previously converted from the injection wells), we reverse the translation of the vertical injection wells 3, 3', 3 '', ... 3 ⁿ to vertical producers, and vertical producers 2, 2 ', 2'', ... 2 ⁿ to vertical injection, that is, they return to the initial mode of operation of the wells and the cycle repeats. The coolant is injected into horizontal 6, 6 ', 6'', ... 6 ⁿ and vertical 3, 3', 3 '', ... 3 ⁿ injection wells and oil bitumen production from horizontal 7, 7 ', 7'', ... 7 ⁿ and vertical 2, 2 ', 2'', ... 2 ⁿ production wells lead to the full development of bottom-hole zones of vertical and horizontal wells.

The proposed method of thermal impact on the reservoir of high viscosity oil and bitumen allows for additional involvement in the development of sections of the reservoir of high viscosity oil by drilling an additional series of horizontal production wells, which increases the coverage of the thermal effect on the reservoir by adding the movement of filtration fluid flows in it and, as a result, increases coverage ratio (15-30% relative to the prototype).

In addition, the possibility of alternate injection (before the coolant breaks into vertical production wells) of the coolant and the selection of highly viscous and heavy oil, respectively, either into vertical injection or into vertical production wells, which allows increasing oil recovery and increasing the rate by changing the movement of filtration fluid flows. oil extraction from the reservoir (by 20-40%).

Claims (1)

A method of developing a deposit of high viscosity and heavy oil with thermal effects, including drilling rows of vertical injection and production wells, drilling horizontal injection wells along rows of vertical wells, pumping coolant into horizontal wells and selecting high viscosity and heavy oil from vertical production and injection wells, characterized in that under each horizontal injection well within the same reservoir, additional horizontal production is being drilled a well for the selection of high-viscosity and heavy oil, and vertical production and injection wells are arranged in rows in series, while high-viscosity heavy oil is taken from vertical production wells before the coolant breaks out of them from horizontal injection wells, after which the coolant is not pumped into the vertical injection wells and they are transferred to production wells, and those production wells into which the coolant has broken through are transferred to injection wells, in the future, when the coolant breaks through I of the horizontal injection wells in vertical production wells, translated previously from injection wells produce inverse substitution translation of vertical injection wells to the production wells and the vertical upstream - in the injection and the cycle is repeated until full development bottom zones of vertical and horizontal wells.

Images