RU2377401C1 - Natural bitumen production method - Google Patents

Abstract

FIELD: oil-and-gas production.

SUBSTANCE: invention related to oil-and-gas production, particularly to well methods of hydrocarbons field development with horizontal canals reservoir opening and its thermal treatment, can be used for natural bitumen production. Essence of invention: method includes construction wells, horizontal canal reservoir opening through the well, reservoir supply with a heat-carrier, collection of a product in the well and its withdrawal to the surface though riser. According to the invention one of more risers used. Riser executed as sealed heat insulated case, installed on a tank heat insulated cup, inside of which working unit - closed pulling element with piston located, thrower over drive block with sealing element and in its rising branch cylinder located, which connected to exhaust line and located at burial depth in tank. Between its rising and descending branches locate steam pipeline, connected to steam generator and though upper distributing collector and upper remotely controlled valves, dependently on process regime - with all or just part of controlled canals, which in turn connected, when upper controlled valves are in shut-off position, though bottom controlled valves and bottom distribution collector, with tank, and connect case with light fraction catching system.

EFFECT: natural bitumen production efficiency increase because of heat from supplied stem rational use, catching of light fractions into system, primary production preparation in underground tank and its use for risers with high technical-economical factors pumping out.

6 cl, 6 dwg

Description

The invention relates to the field of the oil industry, and more particularly to methods for producing hydrocarbons by borehole methods with opening the formation by horizontal channels with thermal effect on it, and can be used for the extraction of natural bitumen.

A known method of developing deposits of highly viscous oils and bitumen (RF patent No. 22600600, EV 43/24, publ. Bull. No. 4 of 02/10/2005), including the construction of a two-well well, the horizontal perforated part of which passes through the reservoir, and wellhead sections connect the ground section in the form of an arcuate pipeline with the formation of a closed channel, inside which an additional column of pipes is placed, inside which a closed traction element with pistons driven by the ground drive is placed. The method is based on the task of increasing the efficiency of the system by implementing a process of continuous deep pumping oil displacement in an equal bore closed hydraulic channel.

Deposits of high viscosity oils and bitumen, occurring at shallow depths, are characterized by low reservoir pressures, high viscosity and low mobility of products in the reservoir. To implement the proposed method, it is necessary to build a complex, expensive and one-time technical structure, which consists in constructing a well along a predetermined closed path and a cumbersome ground part for a drive and a product reception system. Without the use of additional technological methods, the products will not flow from the reservoir into the perforated part of the well in sufficient quantities. Under these conditions, the effectiveness of the method cannot be high.

The closest is the method of oil production by underground horizontal wells (RF patent No. 2060377, ЕВВ 43/24, 7/04, 21/00, publ. Bulletin No. 14 of 05/20/1996) using thermal action on the reservoir, including the construction of a vertical shaft shaft, closed with a sealed top, revealing the reservoir at its full capacity, the construction of an underground working chamber isolated from the mine atmosphere, drilling from the surface of the horizontal injection and production wells in two tiers, the mouth of which is They can be found in the underground working chamber, pumping coolant from the surface of the reservoir through injection wells through the steam pipe, extracting oil from the producing formation into the underground working chamber, collecting oil into a tank in the form of lifting wells and pumping airlift lifts to the surface.

The disadvantage of this method is that it is not always economically feasible to build technically complex, expensive, and one-time structures at natural bitumen deposits located under cultivated lands and settlements at depths of 40-250 meters, having small reservoir thicknesses, reservoir pressures and reserves. In addition, when pumping products with airlift elevators, the conditions for the formation of stable emulsions are not excluded, which will require additional costs for its further preparation. The steam supplied to the formation is not used to heat the pumped products in the lift in order to reduce its viscosity, which will increase operating costs.

The technical task of the proposal is to increase the efficiency of natural bitumen production due to the rational use of heat from the supplied steam, trapping light fractions in the system, primary preparation of products in an underground tank and the use of elevators with high technical and economic indicators for pumping it.

The problem is solved by the method of extraction of natural bitumen, including well construction, opening the formation from the well with horizontal channels, supplying coolant to the formation, collecting products into the tank and pumping it to the surface with a lift.

New is that the lift is made in the form of a sealed thermally insulated body mounted on a thermally insulated lid of the tank, inside of which a working element is placed in the form of a closed traction element with pistons thrown through a drive unit with seals, and an ascending branch of which is placed in a cylinder connected to the discharge a line and placed to a depth of immersion in the tank, between the ascending and descending branches of it is placed a steam pipe connected to the steam generator and, through the upper distribution the collector and the upper remotely controlled valves, depending on the technological mode of operation, with all or part of the horizontal channels, which in turn communicate with the closed upper controlled valves, through the lower remotely controlled valves and the lower distribution manifold with a tank, and the body is connected to the system trapping light fractions.

What is new is that the formation is opened with several tiers of horizontal channels, which, depending on the technological mode of operation, can be either steam injection or production, and several elevators are placed in the well.

New is the fact that a standard roller-chain chain is used as a traction element, a groove for passing pistons is made on the drive unit, and the distances between them are chosen not less than the immersion of the cylinder in the product and a multiple of the length of the pitch circle of the block.

What is new is that a variable speed motor gearbox is used as a drive to regulate performance depending on the viscosity of the pumped product.

New is the fact that the pistons are attached to the traction element of the working body externally eccentrically.

It is also new that, to replace the working body, its branches on the surface are opened, one branch is connected to the external drive, another working body is connected to the other branch through the external block and dragged into the housing until it appears on the surface and the branches are interconnected.

Figure 1 shows the General layout of the equipment in the well (in the background between the manifolds of the valve conditionally not shown).

In Fig.2 - a fragment of the collector of the tank cleaning system on the leader, B of Fig.1.

Figure 3 is a section aa in figure 1.

Figure 4 is a fragment of the ground part of the lift, view In figure 1.

Figure 5 is a fragment of the underground part of the lift, view G of figure 1.

In Fig.6 - callout D of Fig.3.

The method of extraction of natural bitumen (hereinafter referred to as bitumen) is as follows. In the field being developed, a vertical airtight well 1 is built (Fig. 1), closed at the level of the sole 2 of the formation 3 with a horizontal sealed heat-insulated cover 4, forming a container 5 for collecting products. From above, the well is closed with a sealed chamber 6 with a floor, in which a working elevator and a ventilation system (not shown) are placed. In areas above the roof 7 and below the sole 2 of the layer 3 carry out waterproofing work. Open the formation 3 closer to its sole 2 by alternating horizontal channels in the form of rays with perforated nozzles 8 (Fig. 3) and pipes 9 alternating along the perimeter of the well 1 and pressing them into the formation 3 with a slight rise from the well 1, for example, with a hydraulic jack (not shown). The nozzles 8 are pressed in about 10 meters and they are perforated with holes 10 (or longitudinal grooves) along the entire length. The length of the indentation of the pipes 9 into the formation 3 should be maximum in the technical capabilities of the equipment used for this and can be 150 meters or more, and perforate them starting from a distance of more than 20 meters from the well 1. Other technological methods may be used depending on the specific conditions of the well construction. layout of pipes 8 and pipes 9 in the reservoir. Depending on the equipment used for this equipment, the nozzles 8 and pipes 9 can be both composite and solid, and their material is metal or non-metal, capable of working in reservoir conditions. The coupling of the output ends of the nozzles 8 and pipes 9 with the wall of the well 1 is sealed by known methods. The ends of the nozzles 8 (Fig. 1) and pipes 9 inside the well 1 are connected through remotely controlled upper valves 11 to the upper distribution manifold 12, and through remotely controlled lower valves 11, the middle distribution manifold 13 and the pipe 14 with a capacity 5. At the bottom of the tank 5 is installed the collector 15 with perforated holes 16 (or longitudinal grooves) (figure 2), connected by a pipe 17 (figure 1) through a remotely controlled flow switch 18 with a collector 12.

If necessary, the layer is opened with several tiers of nozzles and pipes.

Pumping products to the surface by a lift. The elevator 19 is made in the form of a sealed thermally insulated housing 20 mounted on a thermally insulated lid 4 of the tank 5. Inside the housing 20, a working element 21 is placed in the form of a closed traction element - a standard roller-chain chain 22 with attached pistons 23, thrown over the drive unit at the top - an asterisk 24 with seals 25. The ascending branch 26 of the working body 21 is placed in the cylinder 27 connected to the flow line 28, and the descending branch 29 is placed in the cavity 30 of the housing 20. The bottom of the cylinder 27 with the working body 20 to the immersion depth are placed in the tank 5. In the housing 20 of the lift 19, between the ascending 26 and descending 29 branches of the working body 21, a steam line 31 is placed, communicated by a pipe 32 (Fig. 4) with a steam generator (not shown), and through a pipe 33 (Fig. 5) , a distribution manifold 12, upper valves 11 with nozzles 8 and pipes 9. The cavity 30 of the housing 20 is in communication with the tank 5 and through a pipe 34 (Fig. 4) with a light fraction collection system (not shown). In the upper part of the housing 20 (Fig. 1) an asterisk 24 is placed with seals 25 and a groove 35 for passing pistons 23 of the working body 21, driven by a gear motor 36 with an adjustable speed. In the upper part of the housing 20 provide clamps (not shown) for fixing the branches 26 and 29 when servicing the lift 19.

The distance between the pistons 23 is chosen not less than the immersion of the cylinder 27 in the product and a multiple of the pitch circumference of the sprocket 24. This condition ensures that the pistons 23 enter the groove 35 of the sprocket 24 during operation of the hoist 19. The pistons 23 can be made of two halves attached to the chain 22 without her disconnecting. In the manufacture of pistons 23 with one-piece and eccentric attachment to the chain 22 with its separation, there is no need to perform groove 35 in the sprocket 24, because for tooth sprockets in the piston make a special groove.

The ends of the nozzles 8 and pipes 9, the housing 20, the manifolds 12, 13, valves 11, the flow switches 18 and the hermetic chamber 6 and other pipelines are thermally insulated (not shown). Installation of equipment in the well is carried out using a working elevator. Workers are provided with personal protective equipment to work in these conditions.

The technology of steam gravity drainage with the injection of superheated steam with a temperature of about 300 ° C is used to select formation products. The essence of the technology lies in the fact that the reservoir is heated with superheated steam to reduce the viscosity of the product and bring it into a fluid state. At the first stage of operation, the steam deposits pump the estimated time through the steam line 31 and the upper manifold 12 with the upper valves 11 open in all nozzles 8 and pipes 9 for more complete heating of the formation 3. At this time, the lower valves 11 communicating them through the lower manifold 13 and the pipe 14 with a capacity of 5, closed. After sufficient heating of the formation, the lower shutters 11 are opened remotely, connecting pipes 8 through the collector 13 and pipe 14 with a capacity of 5, and the steam supply to the pipes 9 is continued. In gravitational mode and under the influence of reservoir pressure, products in the form of bitumen with water and mechanical impurities enter through perforated pipes 8, collector 13 and pipe 14 into container 5. In container 5, mechanical impurities fall down, bitumen floats up in water, and light fractions through the cavity 30 of the housing 20 and the pipe 34 enter the capture system (not shown), i.e. the primary stage of product preparation takes place. Chemicals can be used to speed up this process. Depending on the applied technological mode of formation operation, the nozzles 8 and pipes 9 can be either steam injection or operational. From the tank 5, the products are pumped to the surface by a lift 19.

The elevator 19 operates as follows. The gear motor 36 rotates the sprocket 24, which moves the working body 21 upward along the cylinder 27. At the same time, under the action of immersion, suction and adhesion forces of the product with the working body 21, the latter constantly carries it upward along the cylinder 27 until it is removed to the surface. Sealers 25 clean the working body 21 of the product, and it is discharged into the flow line 28. In the tank 5 there may be products with different viscosities - from water to bitumen. Therefore, the optimal operating mode of the lift is achieved by changing the speed of the working body, depending on the viscosity of the pumped product.

Maintenance of the lift is reduced to replacing its working body 21 as it wears out. To do this, fix its ascending 26 and descending 29 branches, disconnect them on the surface, attach the ascending branch to an external drive (not shown), attach a new working body to the other branch through an external block (not shown), and, freeing the branches, drag it through the case 20 lifts to appear on the surface and interconnected.

If necessary, several elevators can be placed in the well.

To clean the container 5 through the steam line 31 (Fig. 1), a collector 12, a flow switch 18, a pipe 17, steam is fed into the collector 15, which, leaving the perforated holes 16 (Fig. 2), mixes mechanical impurities with water, forming a pulp, which is pumped to the surface by a lift.

The equipment is carried out in explosion-proof quick-assembled modular design, equipped with safety, control and video surveillance devices.

Technological processes are controlled by the operator from the day surface. After the full development of the reservoir, the removable equipment of the well is dismantled, the formation zone is sealed, if necessary, it is washed and used for other purposes or filled up. In all cases, ensure environmental requirements.

The technical and economic advantage of the proposed method for the extraction of natural bitumen is as follows. It becomes possible to efficiently warm the formation with the least heat loss of the injected steam, collect products in an underground tank from a large area where it is first prepared, take light fractions into the collection system and pump it to the surface with a lift, achieving optimal modes of operation depending on viscosity pumped products by a simple change in the speed of movement of the working body. Due to the fact that the branches of the working body are mutually balanced, the maximum bore of the cylinder is used for pumping products, and its filling occurs not only under the influence of immersion and suction pressures, but also by forced enthusiasm by the working body, the lift has high technical and economic parameters when pumping such products. A simple scheme for replacing a worn working body, servicing its drive part on the surface, and simultaneously heating the pumped-out product with steam heat, at which its viscosity decreases, helps to lower the operating costs of the elevator. The proposed scheme of the lift allows you to feed steam through it into the reservoir, pump out products with different viscosities and mechanical impurities, and divert light fractions into the collection system. The method allows you to open a productive formation with minimal impact on it, apply, depending on the stage of field development, various technological methods of impact on the formation without changing equipment and conduct rational selection of products from different sections of the formation. The fact that the initial preparation of products takes place in an underground tank and the conditions for the formation of stable emulsions during its pumping are excluded, reduces the cost of its general preparation on the surface, which in some cases can reach up to 60% of the total production costs. The process control of bitumen mining is carried out remotely according to a given program and in automatic mode. Safety and environmental issues are being addressed. After developing the reserves of bitumen deposits, the well can be used as an underground reservoir for other purposes (for storing oil, water, fertilizers, industrial waste, etc.).

Thus, using the proposed technical solution, it becomes possible to increase the efficiency of the extraction of bitumen occurring at shallow depths.

Claims (6)

1. The method of extraction of natural bitumen, including well construction, opening the formation from the well with horizontal channels, supplying coolant to the formation, collecting products into the tank and pumping it to the surface with a lift, characterized in that the products are pumped to the surface with several lifts or a lift, while the lift performed in the form of a sealed thermally insulated housing mounted on a thermally insulated lid of the container, inside which the working body is placed in the form of a closed traction element with pistons thrown over the drive unit with seals and the ascending branch of which is placed in a cylinder connected to the flow line and placed to a depth of immersion in the tank, between the ascending and descending branches there is placed a steam pipe connected to the steam generator and through the upper distribution manifold and upper remotely controlled valves, depending on the technological mode of operation, with all or part of the horizontal channels, which, in turn, communicate with closed upper controlled valves, black bottom of remote-controlled valves and a lower manifold, with the container and the housing is connected to the light ends recovery system. 2. The method according to claim 1, characterized in that the reservoir is opened with several tiers of horizontal channels, which, depending on the technological mode of operation, can be either steam injection or operational. 3. The method according to claim 1, characterized in that a standard roller-chain chain is used as a traction element, a groove is made on the drive sprocket to pass the pistons, and the distances between them are chosen not less than the immersion of the cylinder into the product and a multiple of the pitch circumference of the sprocket. 4. The method according to claim 1, characterized in that a variable speed motor gearbox is used as a drive to control the capacity depending on the viscosity of the pumped product. 5. The method according to claim 1, characterized in that the pistons are attached to the traction element of the working body externally eccentrically. 6. The method according to claim 1, characterized in that to replace the working body, its branches on the surface are opened, one branch is connected to an external drive, another working body is connected to the other branch through the external block and dragged into the housing until it appears on the surface and connected branches among themselves.

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