Oil deposits extraction complex. RU patent 2246000.

FIELD: oil and gas extractive industry.

SUBSTANCE: device has force and product pipelines, column of thermo-isolated pipes, steam generator. Steam generator is made in form of system for feeding easily-boiling liquid. Said system contains thermo-isolated force pipeline with reduction assembly for adjusting amount and pressure of easily-boiling liquid and sprayer. Sprayer serves for dispersing easily-boiling liquid on smallest drops and forming foam of mixture of bubbles of easily-boiling liquid steam and oil from bed. Also provided is compressor for raising foam, cooling machine for transferring steam of easily boiling liquid to liquid state. Inputting pipeline is placed coaxially outside the force pipeline. Output of input pipeline is connected to separator input, and separator output - to cooling machine input.

EFFECT: higher efficiency.

1 dwg

The invention relates to the development of oil fields, in particular complexes exposure on the formation containing viscous oil.

Known complexes development of oil by injection of coolant (hot water or steam) into the reservoir. Thermal methods of treatment of oil reservoirs. Reference manual “Nedra”, 1995, s,

The complex of steam injection on the column insulated tubing, which is above the roof of the mined seam establish heat-resistant packer. The system provides a reduction of heat loss, protect the casing from the temperature difference. For stimulation using steam generators with different parameters. Bourget, J., Surya P., Komarno M.: Thermal methods of EOR. TRANS. with Franz. M.: Nedra, 1988, s.

The complex development of oil, containing the discharge and intake piping, tubing insulated pipes, the steam generator. The patent of Russian Federation №2187630, IPC: E 21 In 43/24, 2002, bul. No. 23 (prototype).

A disadvantage of the known complexes of the development of oil deposits is low coverage of the impact process in the section of the deposits. In most cases, the vapor comes mainly in the upper part of the reservoir due to gravitational forces, hydrostatic pressure of the liquid column and the oil is not used.

This invention eliminates the drawbacks and prototype.

The technical result of the invention is to improve the efficiency of the gravitational expiry of oil and its hydrodynamic expiration due to steam stimulation, containing high-viscosity oil.

The technical result is achieved by the fact that in the complex development of oil, containing the intake and discharge pipelines, tubing insulated pipes, steam generator, the steam generator is made in the form of a system of feed boiling liquid containing thermally insulated pressure line with a pressure reducing unit for controlling the amount and pressure of the boiling liquid and a nozzle for dispersing boiling liquid into tiny droplets and create a foam from a mixture bubbles to the boiling liquid and oil from the reservoir, a compressor for raising the foam, refrigeration unit for translation pair boiling liquid in a liquid state, while the intake pipe is located coaxially outside the discharge pipe, the output intake pipe is connected to the input of the separator, and the separator with the inlet of the refrigeration unit.

The invention is illustrated in the drawing. The drawing is a schematic representation of the oil production from the wells containing the intake pipe 1, otkachnoj pump 2, a compressor 3, a cooling unit 4, the pressure of the heat-insulated pipe 5, reducing the node 6, the nozzle 7, the separator 8, a connecting pipe 9 and the starting device 10.

Complex oil works as follows. In a well in a thermally insulated pressure pipe 5 downstream node 6 and the nozzle 7 at the end through the nozzle 7 and serves on the bottom of the wells boiling liquid: liquid ammonia or carbon dioxide. Liquid ammonia or carbon dioxide serves under pressure sufficient to disperse filed liquid in the nozzle 7 into tiny droplets, and create a foam from oil and bubbles boiling liquid. Next, the thus obtained foam rises up well under the action of external compressor (not shown), and also under the action of the pressure of saturated vapors of the boiling liquid. A pair of liquid separated by the separator 8 and is served in the cooling unit 4, where they are transferred to a liquid state and return again to the bottom of the well. The number and the working pressure boiling liquid regulate downstream node 7 for process optimization in specific conditions.

Getting to the bottom of the well, boiling liquid passing through the nozzle 7, is broken into tiny droplets (dispersed) and evaporates, forming a bubble foaming mixture. The density of this foam ρ p can be reduced to values 3-10 times lower density of pure oil. Therefore, when the pressure of the reservoir, the external compressor and the vapor pressure that is equal to, for example, 10 ATM, the foam rises to a height of 300-1000 m This provides further evacuation from the well.

Under the forces of gravity or force increased pressure in the oil reservoir of the oil in the well rises to a level H above the bottom of the well, covering the nozzle 7. In the nozzle 7 through the pressure reducing node 6 serves for pressure insulated pipe 5 of the refrigerating unit 4 boiling liquid. Getting to the nozzle 7, it is atomized, vaporized and mixes with the oil into a foam whose density ρ p is many times lower than the density of oil. The resulting foam by Archimedes ' principle and under the forces of gravity rises by collecting pipe up to a new level N-1 , which is determined from the relation:

N 1 =N· (1+ρ netten /ρ foam ).

Oil rising from the foam is chosen by the pump 2, and the steam is separated by the separator 8 and is returned through the connecting pipe 9 in the cooling unit 4. Run the whole system in action produce the starting device 10 with the power source.

Using as a boiling liquid ammonia (boiling point T TRC =-33° (240K), at a pressure of 1 ATM heat of vaporization r=1500 kJ/kg), during the evaporation of 1 kg of ammonia is the birth of bubbles total 1.73 m 3 . When mixing this volume of 1 m 3 of oil foam volume 2,73 m 3 weight 10 3 kg and density foam ρ p =370 kg/ m 3 .

At a gauge pressure of 10 ATM, the foam rises to the level of 300 m If excessive pressure is small, the additional pressure drop in the well due to the saturated vapor pressure becomes crucial. For ammonia vapor pressure at the temperature of +20÷ 30° With 10-15 ATM, respectively. Therefore, the height of rise of the foam will be determined by vapor pressure.

To calculate the specific system pumping oil from a well with a depth of 1 km we assume that in the foam volume of bubbles in 10 times more than the volume of oil. Then density foam ρ p is 10 times less than the density of oil ρ N. For definiteness, let us take ρ n =800 kg/m 3 , and ρ n =80 kg/m 3 . If you take the vapor pressure of ammonia P=8· 10 5 PA (8 ATM), then the foam will completely fill the borehole with a depth of 1 km

For clarity, it is convenient to take the cross-sectional area of the hole S=0.1 m 2 , and the flow rate of the foam from the well v n =1 m/s,

1 second from the well will enter the gas volume V g =0.1 m 3 and the oil volume V h =0.01 m 3 or mass of M h =8 kg. If we assume that the density of the saturated vapor of ammonia under normal conditions ρ am =0.6 kg/m 3 , then the mass of the released gas will be the value of M am =0,06 kg To create a continuous process of pumping oil performance N=8 kg/s you want to upload the same amount of liquid ammonia using a refrigeration unit, that is, 0.06 kg/s For condensing vapors should be cool, taking away the heat of condensation in the amount of: Q hol =r am · M am =1,5 (MJ/kg)· 0,06 (kg)=90 (kJ) per second. Here, r s is the specific heat of vaporization of ammonia.

It should be noted that the evaporation of ammonia in the well causes a slight cooling of the oil. However, this cooling is relatively small. Heat oil has a value of 2 kJ/kg· K, respectively, 8 kg of oil transfer heat to the ammonia 16 kJ/K. Since the ammonia takes away from oil ~ 100 kJ/s, the cooling oil is on Δ T=6° C. Provides estimates are approximate. You should consider changing the volume and number of bubbles on the well depth due to changes in hydrostatic and hydrodynamic pressures. In particular, when a pressure change of 1 ATM on the surface layer of oil to 10 ATM at the bottom of the well (the thickness of the layer of oil), the amount of bubbles is reduced 10 times. Therefore, the average value of the volume of the bubbles throughout the entire layer thickness is 0.5-0.6 of the maximum value. As a result of this rise of the foam will be no 1000 m, and 500-600 m, when considering only static mode without taking into account the emergence of new bubbles, their movements and forces gas vapor pressure inside the bubbles when lifting. In addition, the reservoir can produce oil in amount greater or less than 8 kg, which was adopted in the assessment. Therefore, the volume of the bubbles and the amount of the working environment must be changed due to the reduced supply of ammonia in the well.

The second example of oil production based on the use as a working fluid of carbon dioxide. It is attractive because the 2 vapour pressure at temperature 20-30° reaches 40-50 ATM. This allows you to get a particularly viscous oil with any depth. However, the comments made above about the influence of hydrostatic pressure, as well as the need for more cooling of the working fluid (T TRC =-76° (C) require calculation of the possibilities of its practical application to specific fields.

The most important point is the physical basis of oil production in this complex. As soon as the bubble volume V 0 was born in liquid (oil), it is affected by Archimedes buoyancy force: F=V 0 · (ρ oilρ pair )· g, where g is the acceleration of free fall. The presence of this force, caused by the action of gravity, allows you to generate foam along the entire depth of the borehole. The work of this force account work vapors of the working fluid during expansion, ultimately, aims to increase the difference between the pressure of the surrounding oil reservoir and the pressure at the bottom of the well. According to the law of communicating vessels, the oil is constantly fills the annulus pressure 5 and intake pipes 1.

The complex development of oil containing injection and discharge piping, tubing insulated pipes, steam generator, wherein the steam generator is made in the form of a system of feed boiling liquid containing thermally insulated pressure line with a pressure reducing unit for controlling the amount and pressure of the boiling liquid and a nozzle for dispersing boiling liquid into tiny droplets and create a foam from a mixture bubbles to the boiling liquid and oil from the reservoir, a compressor for raising the foam, refrigeration unit for translation pair boiling liquid in a liquid state, while the intake pipe is located coaxially outside the discharge pipe, the output of the intake pipe is connected with the entrance of the separator, and the separator with the inlet of the refrigeration unit.