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Development method of underwater gas-hydrate deposits

Development method of underwater gas-hydrate deposits
IPC classes for russian patent Development method of underwater gas-hydrate deposits (RU 2543389):
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Method of water-producing well recovery Method of water-producing well recovery / 2543005
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Device for oil recovery intensification Device for oil recovery intensification / 2539481
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Rapid-moving eduction column, method for its installation (versions) and safety device for it Rapid-moving eduction column, method for its installation (versions) and safety device for it / 2539045
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Oil-well operation unit Oil-well operation unit / 2538010
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Unit for operation of water supply wells Unit for operation of water supply wells / 2536521
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Method for oil extraction and device for controlling pit-face thermal and pressure parameters during oil extraction Method for oil extraction and device for controlling pit-face thermal and pressure parameters during oil extraction / 2244102
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Well cluster operation method / 2245993
Method includes full raising of cement in behind-pipe space up to mouth, sectioning wells by electro-isolating compounds from oil transporting system or bed pressure support system and use of cathode protection plant as cathode protection station with current controller. For each well time needed for completing cathode polarization of well is determined as well as time for well depolarization, during which potentials on well of cluster are lowered to minimal protective values. On each cluster well cyclic mode of cathode protection plant is performed: cathode polarization during completion of cathode well polarization and well depolarization during lowering potential on well to minimal protective values. During depolarization of one well cathode polarization of other cluster well is performed.
Fully automated device for oil extraction Fully automated device for oil extraction / 2246608
Device has axial transmission and soft stripe support system. Axis connects electric engine to reducer and connected reducer and leading hub, by means of which transmission lines are actuated. After connection of driven hub and device for supporting pump bars, pump bar for actuating well oil pump can be connected. Leading hub can actuate transmission lines, including one connected to balancer, operating synchronously to operation of well oil pump in both directions. Also, device has base, corbel and platform, controller for controlling oil extraction process, transformer, frequency setting transformer, absolute values encoding means and braking tank. Said electric engine, reducer and leading and driven hubs are mounted on the platform. Controller, through setting frequency generator, functioning as main drive, is connected to electric engine. Controller is connected to encoding absolute values means, capable of displaying working conditions and receiving data about position and rotation angle of leading hub. Encoding means for absolute values and braking block compose a portion of device for determining movement and braking. Controller can contain central processing module, input/output module and liquid-crystal display. Controller can be connected to encoding extension means, immediately receiving data about angle, position and rotation speed of electric engine axis.
Method of purification of underground portable water at crude production Method of purification of underground portable water at crude production / 2247195
The invention presents a method of purification of the underground potable water at a crude production. The method provides for limitation of traffic of pollutions by construction of boreholes and pumping in of solutions of reagents. Along the contour of the site of possible pollution they make a net of boreholes with the a controlled inter-pipe and drill string-borehole annulue space - a compound - boreholes, the distance between which and a number of steps is chosen depending on porosity and permeability of rocks. The steps of the compound-boreholes are placed perpendicularly to the traffic route of the natural stream of the underground potable water, and a pumping in of the solutions of reagents is made through annulue space and inter-pipe space of compounds - holes simultaneously with a crude and a gas production from a pay. The technical result is a reliable provision of purification of underground potable water at simultaneous production of a crude and a gas.
Method for extraction of gas-hydrate deposits by drilling / 2247827
Method includes extraction of resource by mechanical drilling and extraction of slurry and rock pieces through well. Gas extraction is performed by horizontal drilling with washing and back expansion, with concurrent cleaning and separation of fresh extracted mixture and accumulation of gas. Delivery of expander of ultra-large working size to expansion place is performed through well subjected for backward expansion. Pressure, temperature and composition of washing liquid is adjusted in such a way, that free natural gas, freed during mechanical drilling, was dissolved in drilling mud and separated from it only after passing of separator through rotating preventer. Expander in form of rocker with cutters is used, expanding well diameter up to ten meters and more.
Method for extracting liquid from a well Method for extracting liquid from a well / 2248443
Method includes insertion of compound of foam-forming and gas-forming substances, dissolving these in bed water, and forming of gas and foam and replacement of well liquid with foam, while as foam-forming substance sulphonole is used with sulphamine acid as reaction initiator. Liquid is extracted in two stages: at first stage upper portion of liquid column is piston-effected, at second stage water-soluble foam-forming substance is injected into well with foam stabilizer and reaction initiator, as well as gas-forming substance, while water-soluble foam-forming and gas-forming substances are inserted into well directly after piston-effecting, and water-soluble foam-forming substance additionally has surfactants. Mass of foam-forming substance is determined from conditions: Mff=(0.005-0.01)KMw, where K - component coefficient, Mw - mass of water removed from the well. As gas-forming substance, ammonium carbonate is used in amount 40-50 kg for 100 linear meters of water column in a well. Piston-effecting is performed with productiveness in no less than two times greater than well debit.

FIELD: oil and gas industry.

SUBSTANCE: method involves destruction of massif of a hydrate-containing manifold with high-pressure water jets, formation from destructed material of pulp in a near-bottom volume covered with a dome, lifting of the pulp containing gas and gas-hydrate onto a floating structure via a pipeline and separation of the pulp into gas, water and solid material with gas transfer to a state suitable for transportation. According to the invention, massif of the hydrate-containing manifold is converted to a solid body-liquid fine suspension with gas-hydrate particle size of 10-20 mcm. For that purpose, it is influenced with high-pressure jets formed in the near-bottom volume covered with the dome. Besides, the volume of the pulp formed in this volume is treated with an ultrasound with parameters causing cavitation effects in it. A hydrate-containing suspension is formed with content in it of a disperse phase of gas-hydrate of up to 20-25%. Capacity of destruction devices of massif of the hydrate-containing manifold is controlled proportionally to pressure in the pipeline in its near-bottom section. An ice pulp formed at dissociation of the gas hydrate is used for cooling of compressed gas - a product of dissociation of a gas-hydrate pulp.

EFFECT: increasing well performance efficiency of a gas-hydrate deposit.

6 cl, 5 dwg

 

The invention relates to oil and gas industry and, in particular, to the development of deposits (deposits) of gas hydrates.

There is a method of field development, gas hydrates, including the drilling of deposits across the layers, the formation of the heat flow in the underlying underlying the formation and selection of hydrocarbons from the overlying gas hydrate formation, and the formation of the heat flow carried out by initiating in-situ burning and maintenance of the combustion front in the underlying layer by feeding the oxidant through the annulus between the tubing - the tubing and the production column with perforated holes on the initial part of the horizontal section, the length of which is chosen from the condition of providing warm-up formed by the decomposition of gas hydrates gas mixture to a temperature prevent the formation of gas hydrates in the course of its movement in the interval from the roof of the underlying reservoir to the wellhead, and the selection of the hydrocarbon is natural gas with water to produce through multilateral perforated horizontal branch (see EN NO. 2306410, EV 43/24, 2007).

The disadvantage of this method is that its implementation must also be located below the reservoir, the gas guide is the ATA, of which is the production of gas, the underlying layers of hydrocarbons (oil or gas) capable of in-situ combustion with heat transfer in the overlying gas hydrate formation. Deposit with such arrangement of the layers is quite unique and therefore, the application of this method is limited. Artificial formation downstream of the hydrocarbon reservoir increases the cost of well construction, complicates the technology of gas production and leads to lower profitability of gas production from hydrates. In addition, for the implementation of the method it is necessary to pump large quantities of air into the reservoir, spending a large amount of electrical energy.

There is also known a method of extracting gas from gas hydrates (see EN NO. 2169834, EV 43/16, EV 43/24), including supply of heat to the zone of decomposition of gas hydrates by holding in the zone of decomposition of gas hydrates exothermic catalytic reaction with a specific heat greater than the heat of dissociation of solid gas hydrate. The catalytic reaction using oxidation, including electrochemical, methane in the synthesis gas or partial oxidation of methane to CO2and water, or oxidative dimerization of methane, or the oxidation of methane to methanol. Moreover, the liberated gas is subjected to additional chemical processing directly edstone in the area of production. Moreover, the heat generated directly in the zone of decomposition of gas hydrates during the catalytic reaction, is spent on maintaining the reactor in autothermal mode, and the decomposition of the surrounding gas hydrates.

This method has the following disadvantages.

High probability of explosions in the zone of decomposition of gas hydrates at carrying out exothermic catalytic reactions of methane oxidation due to the fact that a mixture of methane with air (oxygen) is extremely explosive (limits explosive limit: lower 5 vol.%, top 15 vol.%). The in-situ explosions can lead to the formation of cracks in the layers, isolating the zone of gas hydrates, and, as a consequence, uncontrolled depressurization of the latter and to an environmental disaster in the area of gas production. To reduce the danger of explosion, it is necessary to use in the well in the extreme conditions of complex high-precision equipment, dosing quantity of the interacting substances, which leads to an appreciation of the technological equipment and to lower profitability of gas production.

Use as catalysts compounds of rare earth elements of La2EN2(or Ir2)O7, perovskite type LaRhO3containing rare-earth metal oxide type system NiO-CaO, NiO-MgO, CoO-MgO, NiO-rare earth oxide,Ni/Al 2O3, Ni-containing complex oxide systems of perovskite-type LaNi1-xRhxOyincreases capital and operating costs (the latter is required when the periodic replacement of the catalyst) technology gas production and reduces the profitability of production.

The high energy cost of the oxidant injection of methane, in particular of air from atmospheric pressure to the pressure in the zone of gas hydrates (963 kW 1 kg/s of air).

Also known the way of development of marine gas hydrate deposits, including the destruction of hydrate serving bottom water temperatures of 1-2°C exceeds the equilibrium conditions for development, the rise of the pulp containing gas and gas hydrate on a floating basis through the pipeline and separation of the pulp for gas, water and solid material (see General. inform. Ser. Information support of the all-Union scientific-technical programs, vol.3. M: Negatron, 1986).

The disadvantage of this method is the high energy consumption. The cost of energy necessary for heating the slurry to a temperature of decomposition of gas hydrates and its transportation. The more the performance of the system, the greater will be the energy costs ceteris paribus. Indeed, were conducted in the initial conditions, the heat capacity of substances 1 m3pulp extending t is approximately 49-10 3kJ/°C. Thus, for heating the whole of the pulp at the bottom to a temperature exceeding the equilibrium at 1-2°C, the water temperature at the surface of the ocean (at different latitudes it is 0-4°C), it takes an enormous amount of heat or a significant expenditure of energy on the flow of heated water from the respective horizons. High energy costs and the rise of pulp on the surface of the hydraulic dredge with a airlift system. For these conditions, they are of the order of 86,4103kJ 1 m3the precipitate.

Also known the way of the development of submarine gas hydrate deposits, including the destruction of the hydrate of high-pressure jets of water, the formation of the demolished material slurry in the bottom of the volume covered by the dome, the rise of the pulp containing gas and gas hydrate on a floating basis through the pipeline and separation of the pulp for gas, water and solid material, with the transfer gas in a condition suitable for transportation (see RU # 113786, AS 50/02, EV 43/01, 2011).

The disadvantage of this method is the high energy consumption of the implementation (you want to provide a vacuum pump for gas sampling from pulp and decomposition of gas hydrates by heating of the slurry). In addition, the lack of efficiency of destruction array sediment collector hydrate as at great depth (km) effective the efficiency of the operation of the compressor will be reduced due to the high pressure environment in the area of mining.

The objective of the invention is to improve the efficiency of mining of gas hydrate deposits.

Technical result achieved when the task is expressed in the possibility of using for the destruction of the hydrate additional physical effects. In addition, ensure the effective rise of the pulp with the exception of the possibility of the formation of gas hydrate plugs in the lifting section of the pipeline eliminates the energy consumption for the dissociation of gas hydrate. Minimized loss section of the pipe work is not associated with the rise of the pulp.

The problem is solved in that way the development of submarine gas hydrate deposits, including the destruction of the array gertsogenauh manifold high-pressure jets of water, the formation of the demolished material slurry in the bottom of the volume covered by the dome, the rise of the pulp containing gas and gas hydrate on a floating basis through the pipeline and separation of the pulp for gas, water and solid material, with the transfer gas in a condition suitable for transportation, characterized in that carry out the conversion array gertsogenauh collector in fine suspension "solid - liquid", which affect him high pressure jets formed in the bottom volume, covered dome, additionally, the volume of the pulp, formed in this volume, process the acoustic field, causing her cavitation effects, in addition, hydrocodonebuy suspension form with a content of disperse phase hydrate up to 20-25%, in addition, the performance of the destruction of the array gertsogenauh collector regulate proportional to the pressure in the pipe at its bottom section, in addition, ice slurry, formed by dissociation of gas hydrate, is used for cooling komprimierung gas product from the dissociation of gas hydrate slurry. In addition, the water remaining after separation from the pulp of gas and solid particles are returned to the cavity of the dome. In addition, the high-pressure jet is formed by means of submersible pumping equipment that is placed in the volume covered by a dome. In addition, the high-pressure jet is formed by the generation of electro-hydraulic shock. In addition, carry out electro-destruction array gertsogenauh collector. In addition, carry out hydrodynamic conversion of gas hydrate components of the pulp in a smaller fraction in the volume of the dome form a circulation material, preferably in an upward spiral.

Comparative analysis of the characteristics of the claimed solution with the characteristics of the prototype and the Academy of Sciences of the logs indicates compliance solutions to the criterion of "novelty".

Signs of a distinctive part of the formula of the invention provide a solution to complex functional tasks.

Signs "...carry out the conversion array gertsogenauh collector in fine suspension "solid - liquid", which affect him high pressure jets formed in the bottom of the volume covered by the dome provide for effective lifting slurry pipeline and complete dissociation of gas hydrate gas and water (with the exception of the possibility of overlap of the pipeline ice or hydrate plugs), in addition, they eliminate the need to supply high-pressure working fluid from the craft in the bottom space, which reduces the requirements to the strength parameters of the pipeline, providing a supply of working fluid to the rock cutting tools.

Signs indicating that "the volume of slurry generated in the volume of the dome "handle acoustic field, causing her cavitation effects help to improve the dispersibility of the particles of the pulp. When it bubbles, resulting from exposure to acoustic cavitation field on the boundary "bottom collector - sea water", slam during the half cycles of compression, creating short-term (duration ~10-6(C) pulse pressure (up to 108is a and more) able to destroy even very hard materials. Criterion erosive activity ultrasonic field increases with increasing hydrostatic pressure. So, for example, at a pressure of 4 ATM, the value of the criterion erosive activity of the ultrasonic field by several orders of magnitude higher than at a pressure of 1 ATM, which allows efficient use of this technological factor at pressure of about 100 ATM, which corresponds to the depth of the gas hydrate reservoir. Cavitation effects through the acoustic field allows not only to increase the efficiency of hydrodynamic impact, but also to achieve proper dispersion of the suspension order (10-20 μm). This effect does not require the supply of the working fluid in the bottom zone.

Signs indicating that "hydrocodonebuy suspension form with a content of disperse phase hydrate up to 20-25%, ensuring a trouble-free lifting of the pulp and complete dissociation of gas hydrate by using the heat capacity of water.

Signs indicating that "the performance of the destruction of the array gertsogenauh collector regulate proportional to the pressure in the pipe at its bottom section, enable you to regulate the process of forming a slurry with a concentration of particles of gas hydrate within the stated proportion, th is allows you to avoid the overlapping section of the pipe plugs of ice or hydrate and eliminate the need for a supply of external energy for dissociation.

Signs indicating that ice slurry formed by the dissociation of gas hydrate is used for cooling komprimierung gas product from the dissociation of gas hydrate slurry", can reduce the cost of energy to drive the compressor.

Signs indicating that "the water remaining after separation from the pulp of gas and solid particles are returned to the cavity of the dome", reduce emissions of methane to the atmosphere is possible, if discharged into the sea water containing residual gas saturation.

Signs indicating that "high-pressure jet is formed by means of submersible pumping equipment that is placed in the volume covered by the dome, provide the possibility of the formation of jets of working fluid directly into the bottom space of one of the possible methods. Signs indicating that "high-pressure jet is formed by the generation of electro-hydraulic shock", provide the possibility of the formation of jets of working fluid directly into the bottom of the second space of the possible methods.

Signs indicating that "additionally carry out hydrodynamic conversion of gas hydrate components of the pulp in a smaller fraction in the volume of the dome form a circulation material, preferably spiral, let t is nice grind the particles of gas hydrate in the composition of the pulp.

Signs indicating that "carry out electro-destruction array gertsogenauh collector, ensure the expansion of the range of damaging effects on the collector hydrate and range of intensities of these effects.

In Fig.1 schematically shows a floating installation, ensure the implementation of the claimed method (electro-hydraulic forming jets of high pressure), and Fig.2 shows the same in the formation of jets of high pressure submersible pumps; Fig.3 gives a diagram of state of the gas hydrate; Fig.4 presents a graph of the temperature - composition of sea water; Fig.5 shows a diagram of the adiabatic and polytropic work of compression of methane from 10 to 20 bar.

In the drawings is shown a floating base 1, the pipe 2, provided with a telescopic pull-out section 3 (i.e., by means of its length changes made with the possibility of automatic operation) placed, for example, in the upper zone of the pipeline 2, under body floating base 1, while outside the cavity of the pipeline 2 posted by cable 4, providing supply of electricity to grutsamaria mechanism 5, the generator of acoustic waves 6 and other consumers of electricity.

The floating base is made in a known manner in the form of a hull-borne corps or semi-submersible, platfo who we are. The means of selection of the gas from the pulp made in the form of the vessel 7, the gas outlet 8 through which the compressor 9 is communicated with the tank 10.

In the first embodiment, the formation of jets of high pressure water gruntboy mechanism 5 is made in the form of a system of parallel, pointed bottom of the pipe 11, the walls of which are made of holes 12 for output streams of high pressure water (preferably equipped with deployme nozzles, increase the "work" being fed through them jets of water), in the cavities of the sockets 11 posted by main electrodes 24 connected via a cable 4 to powerful pulsed current source 13, mounted on a floating basis 1.

Groundsamine device placed in the volume limited by the cavity of the dome 14, a wide end which is facing down and the top is in communication with the pipeline 2. The area of its wide end is exceed the space allocated to the nozzles 11 of the suction head; it (can reach several tens of meters), in addition, the dome 14 telescopically connected with the end of the pipeline 2.

When performing protozanova mechanism 5 according to the second variant it contains a system of parallel, pointed bottom of the pipe 11, the walls of which are made of holes 12 for output streams of high pressure water (preferably equipped with deployme nozzles, Kalevalsky "work" being fed through them water jets). The nozzle 11 is connected to the submersible pump 15 as the source of working fluid, mounted in the cavity of the dome 14.

Submersible electric pump 15 is also designed to supply the working fluid (water) in the pipe 11. In addition, in the cavity of the dome, it is advisable to place at least three jet nozzles 16, which receive water from the submersible pump 15, oriented tangentially in the same horizontal plane or with a slight angle upwards. In addition, the amount of gas hydrates 17.

To prevent overloading of the pipeline excessive amount raised on the surface of the material (to prevent the possibility of his testimonianza ice or hydrate plugs) in the pipeline (10-20 m above its junction with the dome) set the first pressure sensor 18, and above it, on 10-20 meters a second pressure sensor 19, which generates a control signal to change the pace of work protozanova mechanism. If excess amounts in the pipeline is removed from the surface of the collector hydrocodoneee breed specific pressure drop associated with an increased hydraulic resistance exceeds the preset value, the pace of work protozanova mechanism is lowered, i.e. the performance of the destruction of the array gertsogenauh collector regulate about antionline pressure in the pipe at its bottom section. In addition, in the drawings shows the pipeline 20 for discharge into the cavity of the dome 14. The dome can have its own propulsion, including at least three jet nozzles 21, mounted on the outside of the dome, receiving water from the submersible pump 15, which are oriented radially relative to the dome.

The claimed method is implemented as follows.

The initial position of installation: floating base 1 is positioned relative to the mine site (this uses a well-known system of at least three anchor is not shown, or dynamic positioning system, performed in a known manner and includes multiple jets placed along the perimeter of the floating bases), and the pipeline 2 is lowered to the bottom of the water area so that gruntboy mechanism 5 is in direct contact with the surface of the volume of gas hydrates 17, with the dome 14 is also lowered its bottom edge on the surface of the volume of gas hydrates 17, isolating the working area of the nozzle 11 from the remaining volume of water. In this position, the pipe 2 is filled with seawater.

Water submersible electric pump 15 in the pipe 11 leads to the release of high-pressure jets of water from the cavity of the socket (through holes 12). The interaction of these jets with solid hydrate causes the destruction of the latter, including the Isla breakaway pieces of gas hydrate and other solid material.

Additionally, an array of gas hydrate reservoir and the bottom volume of the slurry contained in the bottom of the volume covered by the dome) process the acoustic field, causing them cavitation effects. Bubbles arising from the influence of acoustic field on the partition borders "pieces and particles of gas hydrate - seawater and bottom of the collector - sea water", slam during the half cycles of compression, creating short-term (duration ~10-6(C) pulse pressure (up to 108PA and more) that can destroy even very hard materials. Erosion activity ultrasonic field increases with increasing hydrostatic pressure, which allows efficient use of this technological factor at pressure of about 100 ATM, which corresponds to the depth of the gas hydrate reservoir. Cavitation effects through the acoustic field allows not only to increase the efficiency of hydrodynamic impact, but also to achieve proper dispersion of the slurry (suspension). The dispersion of the suspension by the value of the order of 10-20 microns allows you to use special thermal properties of hydrate particles as a thin thermal objects.

Additionally, creating in the volume limited by the dome 14 spiral upward movement of the material (due to the inclusion in the work badomen the x nozzles 16), provide additional vzaimoperesechenie particles hydrate before their entrance into the pipeline 2.

As you move fine hydrocodoneee slurry pipeline from the bottom (point 1, Fig.3) to the sea surface (point 5, Fig.3), the pressure will decrease and the point of intersection of the isotherm of +2°C (temperature hydrocodoneee suspension with a line of equilibrium "Hydrate-Water + Gas (point 2, Fig.3) hydrate particles will enter the area to the unstable state. After about 20 meters after gas hydrate slurry crosses the line of equilibrium (point 3, Fig.3), the hydrate particles will begin to dissociate into free gas and water.

To start the mechanism of the decomposition of gas hydrate you must fulfill the following conditions:

- to leave the area thermodynamically stable state;

- to bring the heat equal to the heat of dissociation of gas hydrate (430 kJ/kg).

Because the slurry contains 65-85% of sea water, from 0 to 10% of the soil particles and 15-25% of particles hydrate, dissotsiiruut particles hydrate, being surrounded by sea water, will begin to pick up its internal energy and thus reduce the temperature. After the sea water will reduce its temperature from +2 to-1.8°C, it begins to crystallize and give warmth to their crystallization dissotsiiruut particles hydrate. The temperature of gather the same as the receiver heat crystallizing sea water will be -2°C, since the temperature gradient magnitude 0.2°C will ensure the appearance of the heat flux necessary power in terms of the interfacial heat transfer. When this gas hydrate slurry will begin to transform into gasolineras because dissociologist the hydrate would be replaced by particles of water ice. Thus, the pipeline on Board the vessel, starting from a depth of 350 meters, you will move a suspension of particles of species, growing particles of water ice, dissociate of hydrate particles, bubbles of free gas and liquid sea water as the dispersion medium (water of crystallization will allocate 335 kJ/kg of heat energy that will be used particles of hydrate to its dissociation).

Thus, from a depth of 350 meters will begin to operate gas lift, drive which will be the energy stored in the hydrates in the process of their formation on the bottom of the sea.

The temperature of the resulting suspension will be -2°C, but this will not lead to the freezing of water ice particles, because they will be surrounded by an aqueous solution with an appropriate concentration of mineral substances (Fig.4).

The low thermal conductivity of hydrate particles will not be a limiting factor to the kinetics of their dissociation, because if the hydrate particles have dimensions of thermally thin bodies, the magnitude of their thermal conductivity does not affect the heat flux, the which passes through them.

Gas on Board the vessel is subjected to normal commercial processing, for example, pressurized up to 300 kg/cm2in the cylinders of composite fiberglass FRP, the use of which is approved by classification societies, overseeing the design and construction of vessels (see http://www.transoceangas.com/Development_Plan.htm).

In the process of compressing natural gas losteria suspension will be used for cooling, which will reduce the cost of energy to drive the compressor (not shown) through an external source of cold particles of ice that make up the pulp.

In Fig.5 the process 1-2 is normal isotropic compression discharge temperature at compressor +35°C, while the compression 2-3 carried out by polytrope with the discharge temperature at the compressor +20°C by cooling the gas to be compressed by an external cold source. This polytropic process requires 1-3 unit cost of the work to compress the gas 40 kJ/kg, whereas the adiabatic 1-2 cost work in the amount of 100 kJ/kg From the point of view of the law of conservation of energy, cold, as well as the expansion energy of methane in the pipeline, obtained through intermolecular van der Waals forces dissociation of hydrate when it is off the equilibrium path.

Water after the separation from it of rock particles and natural gas prepact the tion should return to the cycle (if there is no possibility of its standard purification from hydrogen sulfide, of carbon dioxide and other non-hydrocarbonaceous gases), since the residual gas saturation when necrose into the sea untreated gases from water can lead to methane emissions into the atmosphere. Solid suspension accumulates in the hopper 22 and either reset by a flexible sleeve on the bottom of the sea (not shown), or a known manner not exported to shore for disposal, if it contains valuable components.

It is known that the seafloor sedimentary formations of sand and silt have or may have fragments of rock, the strength of which does not allow you to destroy them by means of high pressure jets. Thus, on the external surfaces of the pipes 11 posted by additional electrodes 23 connected via a cable 4 to powerful pulsed current source 13, mounted on a floating basis of 1 (they provide the disintegration of rock fragments with high-voltage electrical pulses). On the stage of discharge in the rock channel discharge passes through the areas the location of the local electrical inhomogeneities, i.e., rock inclusions in sandy or muddy ground. Thus, the discharge channel passes through the boundary, generating energy pulses over a short period of time (~10-6C), while in the discharge channel almost instantly increases the pressure up to 109PA. As a result, the channel rasra is and generates a shock wave compression and expanding forms inside the rock mechanical stress, which disintegrate into separate small fragments.

Transportation of natural gas will be in compressed form on specialized courts operating at the transport shoulder to 1000 nautical miles more appropriate from a commercial point of view compared to the use of tankers for transportation of liquefied natural gas.

Thus, the proposed solution can significantly reduce energy costs for the destruction of the gas hydrate reservoir and transportation hydrocodoneee pulp, to provide installation and flexible control modes at high performance gas-lift system.

1. The way of the development of submarine gas hydrate deposits, including the destruction of the array gertsogenauh manifold high-pressure jets of water, the formation of the demolished material slurry in the bottom of the volume covered by the dome, the rise of the pulp containing gas and gas hydrate on a floating basis through the pipeline and separation of the pulp for gas, water and solid material with the transfer gas in a condition suitable for transportation, characterized in that carry out the conversion array gertsogenauh collector in fine suspension "solid - liquids is ü" particle size of hydrate 10-20 μm, what influence, high pressure jets formed in the bottom of the volume covered by the dome, additionally, the volume of the slurry formed in this volume, treated with ultrasound parameters, causing it cavitational effects, in addition, hydrocodonebuy suspension form with a content of disperse phase hydrate up to 20-25%, in addition, the performance of the destruction of the array gertsogenauh collector regulate proportional to the pressure in the pipe at its bottom section, in addition, ice slurry, formed by dissociation of gas hydrate, is used for cooling komprimierung gas product from the dissociation of gas hydrate slurry.

2. The method according to p. 1, characterized in that the water remaining after separation from the pulp of gas and solid particles are returned to the cavity of the dome.

3. The method according to p. 1, characterized in that the high-pressure jet is formed by means of submersible pumping equipment that is placed in the volume covered by the dome.

4. The method according to p. 1, characterized in that the high-pressure jet is formed by the generation of electro-hydraulic shock.

5. The method according to p. 1, characterized in that exercise electro destruction array gertsogenauh collector.

6. The method according to p. 1, characterized in that the additional is but carry out hydrodynamic conversion of gas hydrate components of the pulp in a smaller fraction why in the volume of the dome form a circulation material preferably in an upward spiral.

 

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