UA77590C2 - Methane hydrate electric power plant - Google Patents

Abstract

The invention relates to the field of electric power engineering. A methane hydrate electric power plant transforms energy of methane hydrates deposits of which are concentrated at bottom of water reservoirs. The power plant comprises equipment of the bottom with floating unit, a transportation pipe with gaslift, this is fed from dry gasholder, a floating chamber in which there is screw separator, a wet gas-holder-smelter with heat exchanger, gas and steam turbines with generators and heat exchanger, and supplementary equipment. Methane hydrates loosened in the bottom are lifted by transportation pipe to the floating chamber where those are partially separated in the crew separator. Releasedmethane is directed to the dry gasholder where from it can come to the gaslift of transportation pipe and to the gas turbine. In the wet gasholder methane hydrates are smelted by heat of the steam turbine exhaust. The gas turbine with steam-gas cycle is fed by gas and hydrate water from the wet gasholder-smelter and from other gas sources. The steam turbine is fed with steam from hydrate water from the wet gasholder, this is overheated in the heat exchanger through which exhaust gases from gas turbine pass. The invention promotes more complete extraction of energy from methane hydrate deposits.

Description

Description of the invention

The invention relates to energy. 2 The ice that forms underwater at the sources of rivers has a simple origin. Methanobacteria decompose the organic mass carried into the sea. Methane is formed, which dissolves in water. At the right pressures and temperatures, water and methane form methane hydrate crystals.

Marine deposits of methane hydrates were first investigated by Yu.F. Makogon (P1, 2, Z), working in the 1960s at VNDI Gas, in Moscow. 70 Methane hydrates are also formed from methane of mineral origin during the filtration of gases through bottom layers. Therefore, deposits of methane hydrates are often found near oil and gas deposits. One of the prerequisites for the extraction of methane hydrates is the preliminary extraction of oil and gas deposits.

In the crystals of methane hydrates, up to 136 water molecules are bound, which form nanotubular or nanolayered structures with so-called "Vanderwals" intermolecular bonds, into the cracks of which 19 gas molecules are drawn. Methane in hydrates is under a pressure three orders of magnitude greater than the external pressure. During the melting of methane hydrate, gas is released, the volume of which exceeds the volume of methane hydrate by 70-300 times. The specific gravity of methane hydrate is 0.7-0.8 g/cm3, while the specific gravity of ordinary ice is 0.91 g/cm 3. Methane hydrate has a plump structure in the form of petal crystals with a length of 1 to 7.5 cm. Hydrates are located at the bottom and under the seabed in several layers 30-50m thick. In the entire Black Sea, methane resources in gas hydrates 720 are estimated at 100 trillion cubic meters, and near Crimea at 20-25 trillion cubic meters, assuming a utilization factor of 0.3. The bottom soil is also saturated with gas. Sludge raised to the surface will give gas with a mass of up to 1095.

If we take into account the intensity of patenting, discussions at international conferences (4, 5, 6, v

Thorough research on the use of Black Sea methane hydrates has begun in Ukraine. school 25 Makogon Y.F. (1, 2), who is the author of important studies of methane hydrates, formulated caveats in the development of H.G.P (gas hydrate deposits) in the water area of the seas: (o) 1. There are no impermeable lithological covers above the H.G.P. 2. Shallow depths of productive layers from the surface of the bottom - from fractions of a meter to several hundreds of meters.

Z. Wide placement on the area of productive layers of H.G.P. o 30 4. Relatively low mechanical strength of layers and their cover. 5. If there is a free gas or oil deposit under the gas hydrates, first of all it is necessary (22) to extract oil and gas, after which the gas hydrate deposits should be developed. 6. The change in pressure and saturation of hydrocarbon systems located in a porous medium leads to intensive degassing during the period of action of alternating voltages. Il. 1. page 198, 199). - 35 Important warnings were also sounded at the International Scientific Conference on Energy Saving, which was held in 2004 in Odessa (5).

What can be seen as a danger in the development of gas hydrate deposits? The fact that the destroyed layer of methane hydrates will float to the surface, melt in surface waters and form a dangerous concentration of methane, which can poison, explode, create a rarefied water-gas surface. "

At the same time, technologies are proposed that introduce disturbances into the gas hydrate layer. Driven into a deposit of 60 or so pipes, through which pulses of pressure and melting brines and replacing carbon dioxide, cracks and c gas bags in the loose ice, which is 3295 lighter than water ice, are supplied - this is not a simple uncertainty, it is a threat to end up in :z" methane gas This is a direct violation of Makogon Yu.F.

This invention is focused on the smallest destruction of the deposit. The punching device stirs the surface layer of methane hydrates with disks 415, collects them under the dome and feeds them to the surface through a pipe. Methane hydrates -1 melt on the surface. In terms of extraction and raising to the surface, the prototype of this invention is Makogon's proposal

Yu.F, 2, ZI. - and Ale Smirnov L.F. (4) it was proposed for the first time to use the energy of the released gas for the production of electricity. In |4 this was called the transformation of sea energy into electrical energy. In this part of the 5th Invention, the prototype is the invention |4). se) Smirnov L.F. proposes to pump methane to the bottom of the sea in the lower end of a crystallizer suspended vertically from pipes, create hydrates, and pump water into the crystallizer with a pump. Collect hydrates in melting chambers. For example, 6 cameras are filled. Methane hydrates melt. The gas enters the turbine and drives the turbogenerator. The gas is not burned, but is sent to the bottom of the sea to bring the energy of the sea to the surface together with the new vv / crystals.

All 6 chambers work in turn: they are filled with hydrates, the hydrates are washed with water, the chamber is closed, (F) is heated, gas is released. This gas is sent to the bottom of the sea. Water passes through the turbine, leads to

Ge motion turbogenerator.

In this process, the chemical energy of methane is not used. The disadvantage of the prototype proposed by the patent of Ukraine |4| eliminates this invention.

The methane hydrate power plant is designed to use the energy of methane hydrates. The methane hydrate power plant includes slaughtering equipment, transportation of hydrates to the surface, release of methane, its accumulation, combustion and electricity generation, the plant has drilling devices, a pipe riser, a separator, melting chambers, gas holders, compressors, turbines and turbogenerators, one turbogenerator is driven by a gas turbine with a steam-gas cycle connected to all sources of gas and hydrate water from the wet gasholder - the smelter, and the second turbogenerator is driven by a steam turbine with steam from hydrate water from the wet gas older, superheated by exhaust gases from the turbine of the first generator, the emissions of the second turbine are sent to heat exchangers of the wet gasholder and the floating chamber, the working pressures of the first gas turbine, the wet gasholder-smelter and the separator-pressor are coordinated for the steady movement of particles into the wet gasholder, gas and water from the wet gasholder into the turbines, the gas of small hydrates, sludge, with transport of the pipeline at low pressure, is pumped into a dry gas holder connected to the main line, the first turbogenerator, a wet gas holder and a conveying pipe, and the downhole device is equipped with flotation in the form of a pipe with a pump for pumping out sludge.

The essence of the invention is revealed by the scheme of the methane hydrate power plant shown in the figure. 70 The methane hydrate power plant has drilling devices (items 1-6), which include a dome 1 with a pipe 7, a deposit breaker 2, a device C for moving along the bottom line.

The technique of underwater extraction of construction sand (| also involves the movement of the punching mechanism along the lines. These lines are created with the help of a stretched cable, along which the wheels of the feeding device roll.

Two anchors 4 on cables 5 provide a line along which the feed devices 3 move.

Lollipop flotation is achieved using pipe 6 with a pump. If the sludge is stirred, it is necessary to turn on the pump of pipe 6. The sludge will be removed from the subdome volume. Methane hydrate ice will rise to the surface.

The ice rises to the pipe 7, a lower pressure is created in the pipe than on the outer surface. This is because ice is lighter than water, and at an intermediate height there is a gas pipeline with circuit 9 from the dry gas holder (GS), pos. 10, which reduces the weight of the water column in the pipe and moves the suspension from the bottom to the chamber on the float 11 and 12. This chamber collects methane gas under the dome 11 and water in the chamber 12. To maintain the water level, a water outlet 13 is provided.

The floating camera has a screw separator-presser pos. 14 with hydraulic valve 15.

The hydraulic valve is connected to the wet GM gas holder, item 17, with a sludge outlet 18, a heating radiator 19, a gas supply 20 and a water outlet 21 from the wet gas holder to the combustion chamber 33 of the gas turbine.

A methane hydrate power plant must have a high level of efficiency. This is ensured by the supply of c and reserve sources of fuel and water.

The first turbogenerator has additional fuel supply channels from the dry gas holder, from the main line on which i) the methane hydrate power plant operates and from the neighboring power plant. These connections are technical solutions. They are not shown on the diagram.

Hydrated gas from the wet gas holder 17 is fed to the gas turbine 31, 32, 33. The spent steam-gas mixture is fed to the heat exchanger 27 and to the exhaust 26.

The second turbogenerator 29 has a steam turbine 28 connected to hydrated water 25, which is converted into steam in the heat exchanger 27 Me. yu

Extraction of gas from methane hydrate requires energy consumption in the amount of 3785 kJ/kg of methane.

In the simplest hydrate, 1 kg of methane contains 6.5 kg of water. The heat of vaporization of water is 2256.7 kJ/kg. uh-

Calorific value of methane is 72800kJ/kg. This makes it possible to burn methane hydrate and turn the combustion product into a gas-vapor mixture. The gas turbine will use the chemical energy of methane and the energy of intermolecular van der Waals forces. All elements of the methane hydrate complex are simplified. The cost is significantly reduced.

Three ways of using hydrate gas can be outlined. Sludge from the bottom has small ice crystals. Sludge raised to the surface enters the floating chamber and releases gas, which must be collected in a gas holder and transported to the gas purification and labeling plant.

The second component of the gas flow is small hydrate crystals that fall out of the grease separator. ;" The largest lollipops enter the screw press and are fed either to containers for long-term cold storage or fed to the combustion chamber and further to the gas turbine.

With this scheme of using methane hydrates, the equipment is simple and reliable. -I Literature: 1. Makogon Y.F. Hydrate! natural gases. M. Nedra, 1974, p.

Sh- 2. Makogon Y.F. Gas hydration, prevention of their formation and use. M. Nedra, 1985 p. p. 232 3. Trebin F.A., Makogon Y.F., Basniev K.S. Extraction of natural gas. M. Nedra, 1976 and 4. Smirnov L.F. Method and gas extraction complex for extraction and processing of methane from marine gas hydrate deposits. Patent in the country Mob0O461 A. 15.10.2003. Bull. Mo. 102003. 5. Smirnov L.F. Methane - from gas hydrates of the Black Sea. Ztap 1 "Energy Efficiency 2004". Collection of scientific works of the International Scientific and Technical Conference. Odessa. October 13-16, 2004, pp. 240-250. 6. Shnyukov E.F., Zybrov A.P. Mineral wealth of the Black Sea. K. OMGOR of the National Academy of Sciences of Ukraine, 2004, p. 420.

F) 7. Shnyukov E.F. Disaster in the Black Sea. K. Manuscript 1994, p. 298. name)

Claims (1)

The formula of the invention Methane hydrate power plant, which includes the extraction equipment, tubular elevator, separator, melting chambers, compressors, turbines, generators, which is distinguished by the fact that it additionally has floating chambers, a separator-presser and a gas holder-melter, while one generator is connected to the gas 65 turbine with a steam-gas cycle, which is connected to several sources of gas and hydrate water from a wet gas holder-smelter, and a second generator is connected to a steam turbine, to which a line of hydrate water from a wet gas holder is connected, while the water is superheated by exhaust gases from the turbine of the first generator, the emissions of the second turbine are directed to the heat exchangers of the wet gasholder and the floating chamber, the working pressures of the first gas turbine, the wet gasholder-melter and the separator-pressurizer are coordinated for the steady movement of hydrates into the wet gasholder, gas and water from the wet gasholder into the turbines, the floating chamber serves for gas collection of small hydrates and sludge, the transporting pipe will accept connected to the dry gas holder, which is connected to the pipeline, the first turbogenerator and the wet gas holder, and the drilling device has a flotation device in the form of a pipe with a pump for pumping out sludge. c schi 6) "c) then F IS) i- i - - with . and? -I -I 1 s (42) ime) 60 b5