RU2310744C1 - Method for heavy and/or highly-viscous hydrocarbon production from underground deposit - Google Patents

Abstract

FIELD: hydrocarbon production, particularly to produce hydrocarbons from highly-viscous underground tar sand or heavy oil deposits.

SUBSTANCE: method involves drilling at least two well pairs including injection and production wells, wherein injection well bottom is located in deposit and production well bottom is arranged in deposit below injection well bottom; preparing said well pairs for further operation; creating permeable zone between injection and production wells; injecting heat-carrier agent in injection well and simultaneously producing hydrocarbons from production well. To increase permeable zone between production and injection wells each well is subjected to hydraulic fracturing operation along with propping agent injection before well bringing into operation.

EFFECT: simplified technology and increased deposit development efficiency.

1 dwg

Description

The invention relates to a method for producing hydrocarbons from an underground deposit of tar sand or a heavy oil deposit having a high viscosity. To obtain hydrocarbons from such deposits, their heating is necessary.

A known method of developing deposits of high viscosity oils and bitumen inclined horizontal wells (patent RU No. 2237804, IPC 7 Е21В 43/24, published in bulletin No. 28 dated 10.10.2004), including drilling wells on a specific grid, injection displacing agent through injection wells and selection of formation fluids through production wells, while the wells are drilled along a radial grid, so that injection wells are located along the productive formation closer to the upper boundary of the formation along the most permeable layers, and production wells are closer the lower boundary of the formation, wherein the initial stage of development in all wells is carried thermocyclic treating the formation with steam stimulation, followed by transfer to selection of formation fluids through the production wells with areal influence on the formation through injection wells.

The disadvantage of this method is that the selection of formation fluids from production wells is carried out cyclically, combining it with the injection of steam into injection wells, and this leads to a significant expenditure of thermal energy for heating the formation.

The closest in technical essence is a method of producing hydrocarbons from an underground deposit of tar sand or a heavy oil deposit (patent RU No. 2098613, MKI 6 ЕВВ 43/24, published in bul. 34 of 12/10/1997), containing drilling and preparation for the operation of the injection well, which ends in the reservoir, and the production well, which ends in the reservoir below the level of the injection well, the creation of a permeable zone between the injection and production wells, while drilling and preparation for operation are carried out at least thinking of pairs of wells, where each pair includes an injection well ending in the reservoir, and a producing well ending in the reservoir below the level of the injection well, the second pair of wells facing the first pair of wells, create a permeable zone between the injection well and the producing well of each pair of wells, the injection of water vapor is carried out through injection wells, the simultaneous extraction of hydrocarbons is carried out by producing wells, while the injection pressure in the injection well ine first pair exceeds the injection pressure in the injection well of the second well pair, each injection and production wells have horizontal end sections extending inside the reservoir.

The disadvantages of this method are:

firstly, a complex process of implementing the method.

secondly, the small coverage area of the reservoir with horizontal end sections, and, as a result, the low efficiency of developing heavy oil deposits;

An object of the invention is to simplify the process of implementing the method, as well as to increase the efficiency of reservoir development by increasing the coverage area of the reservoir of heavy and / or highly viscous hydrocarbons in horizontal sections.

The stated technical problem is solved by the proposed method for producing heavy and / or highly viscous hydrocarbons from an underground reservoir, comprising drilling and preparing for operation by at least two pairs of wells, consisting of an injection well that ends in the reservoir and a production well that ends in the reservoir below the level injection well, the creation of a permeable zone between the injection and production wells, pumping coolant into the injection well and the simultaneous selection of hydrocarbons from the producing well.

What is new is that in order to increase the permeable zone between the producing and injection wells, hydraulic fracturing is carried out with proppant injection in each well before putting into operation.

The drawing in longitudinal section schematically shows an image of an underground reservoir of heavy and / or high viscosity hydrocarbons with producing and injection wells.

The proposed method is as follows.

The first pair of wells is drilled, which consists of injection 1 and production 2 wells, and injection well 1 ends in a reservoir of heavy and / or high viscosity hydrocarbons, and production well 2 ends in a reservoir of heavy and / or high viscosity hydrocarbons below level 3 of injection well 1 to a height N, which is, for example, 5 meters, which is determined by calculation and corresponds to the most optimal heating of heavy and / or highly viscous hydrocarbons in the deposits for their subsequent selection to the surface and Depends on the physicochemical properties of heavy and / or highly viscous hydrocarbons in the reservoir.

Next, in the injection 1 and production 2 wells create permeable zones 4 and 5 by hydraulic fracturing with the injection of a proppant layer.

Next, prepare injection 1 and producing 2 wells for operation.

Then, in a similar manner, a second pair of wells (injection and production) is drilled (not shown), as well as permeable zones are created by hydraulic fracturing with proppant injection in each well and the wells are prepared for operation.

Then start the operation of both pairs of wells.

To do this, in the first pair of wells coolant is pumped through injection well 1 into reservoir 3 of heavy and / or highly viscous hydrocarbons and at the same time the selection of heated hydrocarbons from reservoir 3 is carried out through production well 2.

In a similar manner, a second pair (not shown) of wells (injection and producing) is operated.

The proposed method allows to increase the efficiency of the development of deposits by increasing the permeable zone between the producing and injection wells in the deposits of heavy and / or highly viscous hydrocarbons by hydraulic fracturing in each well with proppant injection, and the simplification of the process of the method allows to save material and financial costs.

Claims (1)

A method for producing heavy and / or highly viscous hydrocarbons from an underground deposit, comprising drilling and preparing for operation at least two pairs of wells, consisting of an injection well that ends in the reservoir, and a production well that ends in the reservoir below the level of the injection well, creating a permeable the zone between the injection and production wells, the injection of coolant into the injection well and the simultaneous selection of hydrocarbons from the production well, characterized in that for increased permeating the zone between the producing and injection wells before commissioning in each well, hydraulic fracturing is performed with the proppant layer injected.