The “combustible ice” has started to move. China has started extracting flammable ice from the seabed

Energy is “our everything” on a human scale. More precisely, energy resources. Wars are fought over them, they are accused of exacerbating global environmental problems, without them cannot exist modern society. Therefore, the search for alternative energy sources is at the top of the agenda in many countries. Thus, China this week shocked the world with the official announcement that for the first time it was possible to extract natural gas hydrate, or “combustible ice,” from the ocean floor.

This achievement is already equated in importance to the discovery of shale gas extraction technology in the United States, and the new energy resource is credited with the role of catalyst for the global energy revolution. According to Chinese researchers, there is many times more of this unique fuel in the world than oil, gas and coal combined. This means that with the help of “combustible ice” it will be possible to solve the problem of non-renewable resources. Moreover, the Chinese government website states that “natural gas hydrate is the richest alternative source energy, which will play a strategic role in the future.”

Behind last week More than 120 cubic meters have already been produced from a well located in the South China Sea at a depth of 1200 m. m of “combustible ice” - a mixture of water and gas, reminiscent of a loose snowball. And while some are discussing whether in the future this energy resource will replace all traditional fuel sources, others are in no hurry to call everyone for an energy revolution.

By the way, research on this resource has long been known to science. Soviet scientists expressed their assumptions about the existence of “combustible ice” at the bottom of the World Ocean, and in last years Attempts to organize gas hydrate exploration were made not only by China, but also by the United States and Japan. But, as we see, it was the first one who succeeded.

Expert opinion

Dmitry Nikolaevich Redka, candidate technical sciences, assistant toDepartment of Quantum Electronics and Optical-Electronic Devices, St. Petersburg Electrotechnical University "LETI"

“Essentially, 'flammable ice' is a crystalline compound formed from water and natural gas. That is, it is still the same familiar gas, familiar to us, but in a different “packaging”. Therefore, we must understand that we are not seeing a fundamentally new energy resource, but a non-standard chemical form. And before talking about its revolutionary nature, it is necessary to answer a number of questions. Firstly, it is unknown in what volumes this “combustible ice” can be mined in the future. Next, what modifications can be made with it? What is the best way to extract and transport it? How economically justified and profitable will all this be? The answers here may be ambiguous. However, an attempt to find a new energy resource or a more efficient and safe way receipt of natural gas can only be met positively.”

Illustration copyright Alamy Image caption Methane hydrate or "flammable gas": an important source of energy in the future

China has for the first time extracted gas from methane hydrate deposits at the bottom of the South China Sea - an event that could be a turning point for the future of energy around the world.

Chinese authorities immediately proclaimed this to be a major achievement.

Methane hydrates, also known as combustible ice, contain vast reserves of natural gas.

Many countries, including the United States and Japan, are working to solve the problem of exploiting gas hydrate deposits, but mining them and extracting gas from them is a difficult task.

What is "flammable ice"?

The catchy phrase describes what is in reality a crystalline compound of water and gas.

• Siberian methane influences warming

“It resembles ice crystals, but if you look at it at the molecular level, it turns out that methane molecules are embedded in a lattice of water molecules,” says Professor Praveen Linga from the Department of Chemical and Biomolecular Engineering National University Singapore.

The official name of the substance is methane clathrates or methane hydrates; they are formed under high pressure and at low temperatures in layers of permafrost or on the bottom of the seas.

Despite their low temperature, these hydrates are highly flammable. If you bring a lighter to the surface, the gas contained in the frozen water begins to burn. As a result, hydrates are called “flammable ice.”

As pressure decreases and temperature increases, hydrates break down into water and methane - a very large amount of methane. One cubic meter of the compound releases up to 160 cubic meters of methane, making it a highly concentrated fuel resource.

However, the catch is that the process of extracting flammable gas from gas hydrates is extremely complex and expensive.

Gas hydrates were first discovered in northern Russia in the 60s of the last century. However, research into the extraction of hydrates from bottom sediments began only 10-15 years ago.

Japan occupies a leading position in these studies as a country that does not have reserves of fossil energy sources. Similar research is being actively conducted in India and South Korea, which also do not have oil reserves.

Research in the USA and Canada has its own specifics: they mainly study the possibility of extracting hydrates in permafrost areas - in northern Canada and Alaska.

In Russia, research is underway into the possibility of extracting gas from huge deposits of methane hydrates in permafrost zones in Western Siberia. They are financed by the state corporation Gazprom.

Why is the Chinese achievement so important?

Gas hydrates could change the entire global energy sector and become a major source of energy in the coming years.

Enormous hydrate deposits exist on the floor of all oceans, especially at the edges of continental plates. Different countries are looking for ways to make the production of “combustible gas” safe and profitable.

China claims to have made a breakthrough in this area and Professor Linga agrees.

“Compared to the results of Japanese research, Chinese scientists have achieved impressive success, being able to extract much more methane from extraction,” he explains. “This is a truly significant achievement.”

Gas hydrate deposits are thought to contain 10 times more gas than shale deposits. “And this is only according to the most conservative estimates,” says the scientist.

China discovered "flammable ice" at the bottom of the South China Sea in 2007. Many areas in the waters of this sea are simultaneously claimed by China, Vietnam and the Philippines, and territorial disputes are aggravated by the presence of huge energy resources there.

What will happen now?

According to Professor Linga, China's success is only the first step on a long path to developing a new resource.

“For the first time, the prospects for hydrate mining look promising,” he says. “But I think it won’t be until 2025 (at the earliest) that we see real commercial use of hydrates.”

According to Chinese media, in the Shenhu area in the South China Sea, a production level of 16 thousand cubic meters per day of high-purity gas has been achieved.

However, Professor Linga warns that the exploitation of gas hydrate reserves must be accompanied by the strictest environmental safety measures.

The biggest risk in this area is the uncontrolled release of huge amounts of methane into the atmosphere, which could dramatically accelerate global warming. Methane is a much more effective greenhouse gas than carbon dioxide.

Therefore, the task is to extract the gas and prevent it from escaping.

It was possible to extract “flammable ice” from the bottom of the sea - a compound of water and gas that became a crystalline substance under the influence of high pressure and low temperatures

For the first time, China has extracted “flammable ice” from the bottom of the sea. According to China Central Television, the samples were recovered from a depth of more than 1,200 meters from an underwater well about 300 kilometers southeast of Hong Kong.

"Flammable ice" is a combination of water and natural gas turned into crystalline substance under high pressure and low temperatures. One cubic meter of this energy carrier contains the equivalent of 160 cubic meters of natural gas. “Our country has taken a leading position in the production of combustible ice. This will be as big an event as the shale revolution that happened earlier in the United States,” said the Chinese Ministry of Land and Natural Resources. What is "flammable ice"? Why hasn't it been able to replace natural gas yet?

“Perhaps this is the methane fuel of the future. But at present this is rather from the field of promising scientific developments. Of course, progress is proceeding at a fairly rapid pace, but there are still quite a lot of gas resources on earth that can be extracted at much lower costs and with fewer technological problems. There are simply reserves of traditional gas, for which you need to drill a well only a thousand meters deep and, without special technological gadgets, transport it almost under the original pressure. Therefore, the Chinese are looking for opportunities here, just like others. Japan took steps, even launched some pilot production from one of the special research ships. But such PR launches about the fact that this was done occur regularly. However, we have not yet heard a report of real success.”

When can it start industrial production"flammable ice"?

“The billion dollar question, because it really would be the next revolution. Shale revolution. But shale was also explored for decades before it was possible to select technologies that turned out to be cost-effective. Gas hydrates have also been studied for decades. It has not yet been possible to make this cost-effective. If it can be done on a large scale, it could be a very big shift because gas hydrate resources are very large, much larger than conventional gas and unconventional gas resources. But it’s simply not the time to give any assessments, because, once again, many people are doing this, and quite a lot of effort has been devoted to this. There are government grants, research teams are working. So far it has not been possible to do this on a large-scale, cost-effective basis.”

China discovered deposits of “flammable ice” in the South China Sea in 2007, the Shanghai Daily recalls. According to the publication, the world's first attempts to extract this energy carrier were made in the 60s of the 20th century. China began relevant research only in 1998.

According to publications by Western scientists, signs of the presence of large deposits of flammable ice have been discovered in Siberia. There is no information in open sources that Russia tried to extract it.

This flammable ice will revolutionize the energy industry.

I don’t know what the Japanese are up to, but oil workers from China were the first to be able to extract “flammable ice”—natural gas hydrate—from the ocean floor. This was reported by China Central Television with reference to the Ministry of Land and Natural Resources of the People's Republic of China.

“The fact that we were able to successfully extract this mineral indicates that in terms of the theoretical basis and relevant technologies, China has achieved unprecedented success in this direction<…>. This will be as big an event as the shale revolution that took place earlier in the United States,” said Li Jinfa, deputy director of the ministry’s Geological Research Department.

Also, the Ministry of Land and Natural Resources of China emphasized that such a breakthrough could lead to an energy revolution throughout the world.

The samples were recovered from a depth of more than 1.2 km; the 200-meter underwater well itself is located in the South China Sea, 285 km southeast of Hong Kong.

It is reported that 120 cubic meters were produced in 8 days of work. m of this energy carrier, the methane content of which is 99.5%.

Moreover, 1 cubic meter of this substance is equivalent to 160 cubic meters. m of natural gas in a gaseous state (a car can travel 300 km on 100 liters of gas, while 50 thousand km on 100 liters of “combustible ice”).

Similar mining projects natural resource Other countries are also involved, in particular Canada and Japan, but only China has managed to extract “flammable ice” from the bottom of the sea

WHAT IS METHAN HYDRATE?

Methane hydrate is concentrated at depths of 500 to 2000 meters off the coasts of some continents, usually on steep submarine slopes. It also exists in the Arctic, as seismic measurements and drilling prove. Methane hydrate, composed of water and methane, looks like ordinary gray brittle ice. To the touch - smooth and cold. It has no odor and burns with a yellowish-blue flame.

Methane ice belongs to the so-called “box” compounds. does not arise in them chemical bonds between methane molecules and water molecules. Methane is located in the voids of the crystal lattice of water ice. A single conglomerate of water and gas consists of 32 water molecules and 8 methane molecules. One cubic meter of this substance contains significantly more energy than a cubic meter of natural gas (at the same pressure). In the ice voids of one cubic meter of methane hydrate, 164 cubic meters of gas are “hidden”. The molecules of ice, and therefore methane, are packed more densely here.

Methane hydrate is formed under pressure at depth in the pores of bottom sediments, where organic material and where they reign low temperatures and enough high pressure. The raw materials for it are dead plants and the remains of living creatures supplied by rivers and ocean water itself. Sludge containing carbon is quickly covered by other sediments, and access to it by aerobic bacteria, which would convert biological sediment into carbon dioxide, is stopped. However, the sludge, protected from these microorganisms, becomes food for putrefactive bacteria. The result of their activity is methane.

Accumulations of methane hydrate also form where the oceanic crust collides with the continental crust and goes under it into magma. This circumstance formed the basis of another point of view on the origin of methane hydrate. A hypothesis was drawn from Russian sources that considers not only the organic, but also the cosmic origin of methane.

It has already been said that deposits of methane ice are also found in those places in the ocean where the ocean floor dives under the continent. There are gaps between two giant plates rubbing against each other, through which methane can be released from the magma into the depths of the ocean. This gas was present in the protoplanetary cloud from which the family of planets now orbiting our Sun was born. In the protoplanetary cloud, when the central luminary was lit, differentiation of matter took place: light molecules - gases - were driven away by the pressure of sunlight to the periphery of the cloud (it is no coincidence that the distant giant planets - Jupiter and Saturn - contain huge masses of ammonia and methane in their atmospheres). The Earth, as a planet close to the Sun, was made up of heavier elements, but it still received a fair amount of methane. It is now released from the magma as the pressure in the gap between the continental and oceanic plates drops.

Both assumptions about the nature of methane - organic, that is, secondary, and cosmic - can peacefully coexist.

The depths of the ocean are a sad picture: at the bottom there are a few sea cucumbers, five-rayed stars and hundreds of all kinds of worms. They are all waiting for the food remains of the animals that have occupied the sunny floors of the ocean to fall from above. Rare predator fish swim here in the hope of luring prey with their glowing eyes or spots. Eternal darkness gives no chance for plant life.

But some places in the ocean depths are like oases in the desert - here life flourishes at the bottom. Shell mollusks thrive here, bristle and tube worms crawl along the bottom, and the bottom itself oozes oil and methane. This is a sign that there are deposits of methane hydrate somewhere nearby. Together, carbohydrates and hydrogen sulfide replace light and oxygen for the inhabitants of the depths. Bacteria are quite satisfied with the living conditions provided by the ocean floor. They spend their energy on producing carbohydrates, which serve as food for many inhabitants of this oasis.

In 1997, an exotic inhabitant was discovered in the Gulf of Mexico - a pinkish bristle worm. Hundreds of these creatures swarmed on a block of sedimentary rocks. They made holes for themselves in places where there was access to methane hydrate. Obviously, a new case of symbiosis was encountered here - worms with methane bacteria, but the details of their interaction have not yet been studied. The living world living in the places where this gas is released remains almost unknown.

LARGEST CARBON STORAGE

It is estimated that the planet stores between 10,000 and 15,000 gigatons of carbon in the form of methane hydrate (a giga is equal to 1 billion). These numbers are derived from drilling and seismic surveys in a limited number of locations, but the findings are generalized to areas of the ocean where similar conditions exist.

The huge mass of methane hidden at depth exceeds all known reserves on Earth. natural springs energy. The only question is how to take advantage of this wealth without disturbing the natural balance and without causing a catastrophe similar to the one that happened in the Pleocene. But natural disasters can also destabilize underwater methane hydrate storage facilities. True, currently, with climate warming, the ocean level is rising, thereby contributing to an increase in pressure in the lower layers, and consequently, the stability of methane hydrate.

But if ocean currents change their routes and warm waters penetrates into the lower layers of the oceans, especially in the North Atlantic, the methane ice will melt and the released gas will escape into the atmosphere. Perhaps such an event explains the warming that occurred in the Pleocene. In that era, in a relatively short time, approximately 1,000 gigatons of carbon were released into the atmosphere, according to scientists. The excess carbon that then entered the atmosphere lingered in it for about 140 thousand years until it was absorbed by ocean water and went to build the shells of many marine animals, and then became part of bottom calcareous sediments.

Over the past 1,000 years, humanity, with the help of its furnaces and engines, has released significantly more carbon into the gas envelope of the Earth - from 2,000 to 4,000 gigatons. (Numbers for the Pleocene were obtained by Richard Norris of the Oceanographic Institute and Ursula Rohl of the University of Bremen using cores collected in the Western Atlantic near Florida.)

But the trigger for unleashing a catastrophe in our time can be, according to one of the employees of the University of Oxford, natural disasters: a massive earthquake or volcanic explosions, as a result of which the pressure will decrease (it will become less than 50 atmospheres) and the temperature will rise in the ocean area containing methane hydrate Researchers suggest that underneath the layer of methane ice—its thickness sometimes reaches several hundred meters—there is pure methane. A shaking of the Earth's interior can release this sealed gas upward through cracks in the ice layer.

IS THE BERMUDA TRIANGLE A METHAN HYDRATE TRAP?

According to some researchers, there are places in the World Ocean where methane is released from time to time. Isn’t this or that catastrophe in those places connected with this?

On December 5, 1945, five American torpedo bombers made a training flight. They took off from Florida airfields towards the Bahamas. Half an hour before the planned landing, the command post received a radiogram: the squadron commander reported the incomprehensible behavior of the compass and mysterious glows in the atmosphere. And then the radio connection was cut off. A sixth plane was sent to search for the squadron, but it also disappeared. Neither the cars nor the people were ever found.

Many fantastic explanations arose for the reasons for the disappearance of planes, and subsequently ships, off the coast of Florida. Among those who searched for the real cause of the mysterious disasters was geochemist Richard McIver. He believes that there was a shift in the methane ice covering the bottom in the triangle of Florida, Puerto Rico and Bermuda, and gas, previously sealed by a layer of methane ice, was released and a huge bubble flew through the water into the atmosphere. The planes caught in this stream crashed into the sea.

Some evidence of the possibility of such a catastrophe came from drilling in the Western Atlantic. In the raised core, after the layer where microorganisms are still present, there is a twenty-centimeter layer of silt. Having examined it, a group of scientists from the University of New Jersey made sure that this sludge, as they expected, contained methane ice. A big wave such as a tsunami could well cause the collapse of its underwater slope.

Indeed, conditions off the coast of Florida do not exclude the possibility of shifting methane ice fields. When such a layer begins to move, scientists speculate, gas from under the layers of ice lying on it may well be released and rise to the surface of the ocean in the form of giant bubbles. If a ship or plane gets into such a bubble, they will lose lift and immediately go under water.

This is theoretically possible, agrees US researcher William Dillon, head of gas hydrate research at the American Geological Survey. But, in his opinion, there is no data that would suggest that ships die in the Bermuda Triangle more often than in other places in the ocean.

A different position is taken by Thomas Gold, a geologist at Cornell University. He believes gas emissions from the ocean floor are responsible for at least four major aircraft accidents off North American shores. These disasters happened recently, and many people probably remember them. The last one was a crash into the sea after the launch of an Egupt Air-990 aircraft in October 1999. According to the expert, there is no “normal” explanation for the tragedy. As in all four cases, the cause of the crash must have been something sudden, which prevented the pilots from radioing any details of the problems that arose. Although T. Gold’s explanations met with objections, his hypothesis is supported by two more facts: before the fall of two large machines, a gas flame and fireballs. Maybe it was methane burning that escaped from the water? Gold suggests that the reason for this was a slight earthquake in the coastal zone of the bottom.

Some scientists are skeptical about the hypothesis that free methane can break through a thick layer of methane ice. However, there is evidence confirming the release of methane to the surface of the ocean, although not in such large quantities.

The German expedition ship Polar Star visited the Arctic Laptev Sea and off the coast of Pakistan - in water areas where abundant accumulations of methane hydrate are concentrated. It found craters with a diameter of 20 and 30 meters at the bottom. These depressions, according to researchers, are traces of a gas explosion. In 1997, the Russian research vessel Sergei Vavilov, off the coast of Novaya Zemlya, found itself in an area where intense gases were being released from the sea. Last year, German and American researchers observed bubbles of methane bursting out of water for the first time. It was in the Pacific Ocean off the coast of Oregon. When the research boat Alvin dived, scientists first saw holes at the bottom from which gas bubbles floated. They, according to their assumption, came from accumulations under layers of methane hydrate (its thickness here is 140 meters - according to seismic measurements). Scientists believe that methane is rapidly breaking through the methane hydrate layer: if it seeped slowly, it would get stuck in this layer and freeze.

FIRST ATTEMPTS TO “TAME” METHAN HYDRATE

Not yet full description all reserves of methane hydrate, but even using rough estimates of what Nature has accumulated along the ocean coasts, scientists estimate its energy equivalent as the largest energy reserve available to humanity, if we mean fossil fuels. Only methane hydrate contains more carbon than conventional coal, peat, shale and oil combined (but this compound also includes hydrogen, the most valuable energy carrier). We can confidently assume that this type of fuel will last humanity for many millennia. Question: how to get to him?

In March 1998, a Canadian-Japanese geological expedition in northwestern Canada conducted test drilling in the MacKenzie River delta. At a depth of 900 meters, the drill encountered methane hydrate. A core of fragile ice was extracted to the surface gray, riddled with silt. When scientists put a piece of core into a bowl of water, a rapid, boiling-like release of gas from the ice captivity began. But this energy is very small compared to that which we obtain from the chemical interaction of methane with oxygen, that is, during combustion.

Today there is no well-functioning industrial technology for the production of new fuel. For example, the idea has been expressed that during mining, a roof or canopy should be provided over the layer of this substance, so that an accidental increase in temperature or action chemical substances did not release gas from under the ice layer. Even drilling into methane ice is a risky operation: it can reduce pressure and therefore create instability. Initial data such as the concentration of methane hydrate in bottom sediments are still unclear. Since it remains stable only at high pressures, it has never been possible to lift a large enough block of conglomerate on board.

The United States is projected to increase its energy consumption by 30 percent by 2020. They are ready to use methane hydrate: the country’s Congress allocated $42 million for the development of a program to include the new fuel in the country’s energy balance.

Japan is especially interested in developing methane hydrate production - a country without oil fields, but with vast reserves of methane hidden in the ocean - in and under the ice. The Japanese are striving to develop commercial and industrial mining. Drilling undertaken in the Canadian Arctic, in the MacKenzie River delta, in permafrost conditions, showed that the ice pores in the cores were 80 percent filled with gas. The Japanese are moving their drilling rigs to the side Pacific Ocean, and will try various technologies. However, nothing is known yet about the results of their experimental work.

Geologist Scott Dallimore believes that drilling in Siberia and Alaska has shown gas concentrations in the pores of the ice of 50 to 80 percent. Offshore deposits are larger, but there the gas fill rate is approximately 20 percent. In Russia, in Siberia, there is the Messoyakskoye field, a gas field located in permafrost, the only place in the world where regular natural gas is produced from methane hydrate. This is a fairly powerful deposit that has been operating for many years. A pipeline is laid from it to Norilsk, a major energy consumer.

Unlike permafrost, ocean reserves, as already mentioned, consist of two parts: methane ice, the layer of which can exceed several hundred meters, and a gas bubble held by this layer. Now there is a search for industrial technology that would make it possible to extract gas extremely carefully, without allowing it to leak into the atmosphere: methane and carbon dioxide are responsible for the greenhouse effect - we have all felt its influence in recent years. If, in addition to CO2, large masses of methane also escape into the atmosphere, then its rising temperature may revive the conditions in which our planet found itself 55 million years ago, as discussed at the beginning of the article.

The usual combustion of newly mined gigantic volumes of methane is also not suitable - we will get large quantities still the same CO2, a greenhouse gas, that is, in this case, the atmosphere will begin to warm up more energetically. Nature has a generous gift in store for man, but scientists and engineers will have to rack their brains before they can take advantage of its mercy.

In 2010, American oil workers encountered the unwanted formation of gas hydrates when they were eliminating an oil breakthrough after the death of the Deepwater Horizon platform in the Gulf of Mexico. Then, to control the escaping oil, a special box was built, which they planned to place above the emergency wellhead. But the oil turned out to be very carbonated, and methane began to form entire ice deposits of gas hydrates on the walls of the box. They are about 10% lighter than water, and when the amount of gas hydrates became large enough, they simply began to lift the box, which, in general, was predicted in advance by experts.

Therefore, reports from Japanese geologists very carefully talk about the prospect of developing methane hydrates - after all, the disaster of the Deepwater Horizon drilling platform, according to a number of scientists, including Professor of the University of California at Berkeley Robert Bee, was a consequence explosion of a giant bubble of methane, which formed from bottom hydrate deposits disturbed by drillers.

But no matter how this case ends now for Japanese gas workers, it indicates one important trend - it is gas that is confidently emerging as the main energy resource of the 21st century. The bet on gas is quite justified, since there is a lot of methane on Earth. Global methane reserves in classical fields at the end of the last decade were about 179 trillion cubic meters, with Russia accounting for almost 48 trillion. Second and third places are shared by Iran and Qatar - they have approximately 26 trillion cubic meters each. But fourth and fifth place were shared between themselves Saudi Arabia and the United States, they each have approximately 7 trillion cubic meters of gas, which corresponds to the potential reserves of the Japanese shelf.

If we take into account the so-called shale gas (this is the same methane, only from deposits of a different type), then the United States counts on 30 trillion cubic meters of technically recoverable reserves, China may have 45 trillion, Argentina, closing the top three, - 27 trillion. World shale gas reserves are being assessed by American specialists at 236 trillion cubic meters.

But all these riches pale in comparison to marine or, as they are also called, aquatic deposits of gas hydrates. The total volume of methane in them is assessed 20 thousand trillion cubic meters! These are colossal reserves, they are immeasurably larger than the reserves of shale gas and gas in classical fields. We can say that these reserves will be enough for several centuries of the most merciless exploitation. It is worth recalling that these fields are located in the shelf zone not only of Japan, but also of Russia (especially in the Sea of ​​Okhotsk), as well as Ukraine and Georgia.

If humanity manages to solve the issue of safe production and storage of gas in gas hydrate form, this could open up enormous opportunities for its use, for example, as automobile fuel. This means that the time for a new, gaseous fuel-oriented transport infrastructure is approaching.

Like Cato, who ended each of his speeches in the Senate of Ancient Rome with the demand for the destruction of Carthage, so the author of these lines wants to again appeal to Russian investors - the time has come to create new engines, and most likely - fuel systems, which would run on natural gas - methane, because this is the future. Japanese success is another bell, heralding the beginning of a new era.

MOSCOW, January 18. /TASS/. Russian mathematicians created a model for developing deposits of the richest source of natural gas on the planet - gas hydrates, the concentration of which is high in the Arctic zone, and Skoltech scientists proposed a technology for extracting methane from hydrates. Experts told TASS how the production of such methane will help reduce the greenhouse effect, what are the advantages of new research, and whether there are prospects for the industrial development of gas hydrates in Russia.

Against the greenhouse effect

Gas hydrates are solid crystalline compounds of ice and gas; they are also called “flammable ice.” In nature, they are found in the thickness of the ocean floor and in permafrost rocks, so extracting them is very difficult - wells must be drilled to a depth of several hundred meters, and then natural gas can be separated from the ice deposits and transported to the surface. Chinese oil workers managed to do this in the South China Sea in 2017, but to do this they had to go deeper into the seabed by more than 200 meters, despite the fact that the depth in the production area exceeded 1.2 km.

Researchers consider gas hydrates a promising source of energy, which can be in demand, in particular, by countries that are limited in other energy resources, for example, Japan and South Korea. Estimates of the content of methane, the combustion of which provides energy, in gas hydrates around the world vary: from 2.8 quadrillion tons according to the Ministry of Energy of the Russian Federation to 5 quadrillion tons according to the World Energy Agency (IEA). Even minimal estimates reflect huge reserves: for comparison, BP Corporation (British Petroleum) estimated global oil reserves at 240 billion tons in 2015.

“According to estimates of some organizations, primarily Gazprom VNIIGAZ, methane resources in gas hydrates on the territory of the Russian Federation range from 100 to 1000 trillion cubic meters, in the Arctic zone, including the seas, up to 600-700 trillion cubic meters, but this is very approximate,” - Evgeniy Chuvilin, leading researcher at the Center for Hydrocarbon Production at the Skolkovo Institute of Science and Technology (Skoltech), told TASS.

In addition to the actual source of energy, gas hydrates can become a salvation from greenhouse gases, which will help stop global warming. The voids emptied of methane can be filled with carbon dioxide.

"According to researchers, methane hydrates contain more than 50% of the carbon of the total known world hydrocarbon reserves. This is not only the richest source of hydrocarbon gas on our planet, but also a possible reservoir for carbon dioxide, which is considered a greenhouse gas. You can kill two birds with one stone - extract methane, burn it to produce energy and pump in its place carbon dioxide obtained during combustion, which will take the place of methane in the hydrate,” the deputy director for scientific work Tyumen branch of the Institute of Theoretical and Applied Mechanics of the Siberian Branch of the Russian Academy of Sciences Nail Musakaev.

In permafrost conditions

Today, researchers identify three main promising methods for extracting gas hydrates.

"Before extracting gas from hydrates, it is necessary to decompose them into components - gas and water or gas and ice. The main methods of gas production can be identified - reducing pressure at the bottom of the well, heating the formation with hot water or steam, supplying inhibitors (substances for the decomposition of gas hydrates - TASS note) into the formation,” Musakaev explained.

Scientists from Tyumen and Sterlitamak have created a mathematical model for methane production in permafrost. It is noteworthy in that it takes into account the process of ice formation during field development.

“The formation of ice has pros and cons: it can clog equipment, but, on the other hand, the decomposition of gas hydrate into gas and ice requires three times less energy than when decomposing into gas and water,” Musakaev said.

The advantage of mathematical modeling is the ability to predict the development scenario for gas hydrate deposits, including assessing economic efficiency methods for extracting gas from such fields. The results may be of interest to design organizations involved in planning and exploration of gas hydrate fields, the scientist noted.

Skoltech is also developing technologies for extracting methane from hydrates. Together with colleagues from Heriot-Watt University in Edinburgh, Skoltech specialists proposed extracting methane from gas hydrates by pumping air into the rock layer. "This method is more economical compared to existing ones and has less impact on environment"- explained Chuvilin.

IN this method it is assumed that carbon dioxide or nitrogen is injected into the formation, and gas hydrates, due to the difference in pressure, decompose into their components. “We are still conducting methodological research to test the method and its effectiveness. The creation of the technology is still far away, while we are creating the physical and chemical foundations of this technology,” the scientist emphasized.

According to Chuvilin, Russia does not yet have fully ready-made technologies for the effective extraction of methane from hydrates, since there are no targeted programs to support this scientific area. But development is still underway. “Gas hydrates may not become the main energy resource of the future, but their use will certainly require the development of new knowledge,” Musakaev added.

Economic expediency

The forecast for the development of the Russian fuel and energy complex for the period up to 2035 takes into account the exploration and development of gas hydrate fields among the long-term prospects for gas production. The document notes that gas hydrates can become “a factor in global energy only in 30-40 years,” but a breakthrough scenario is not ruled out. In any case, the development of hydrates will entail a global redistribution in the world market of fuel resources - gas prices will decline, and mining corporations will be able to maintain their income only by capturing new markets and increasing sales volumes. For the massive development of such deposits, it is necessary to create new technologies, improve and reduce the cost of existing ones, the strategy notes.

Considering the inaccessibility of hydrates and the complexity of their extraction, experts call them a promising source of energy, but note that this is not a trend in the coming years - hydrates require new technologies that are still being developed. And in conditions of established natural gas production, methane from hydrates is not in the most advantageous position. In the future, everything will depend on the energy market conditions.

Deputy Director of the Skoltech Hydrocarbon Production Center Alexey Cheremisin believes that methane from hydrates will not be produced soon, precisely because of the existing reserves of traditional gas.

"The timing of industrial production depends on both the economic available technology search, localization and production of gas, as well as from market factors. Gas producing companies have sufficient reserves of traditional gas, so they consider gas production technologies from gas hydrates as a basis for the long term. According to my assessment, industrial production in the Russian Federation will begin no earlier than in 10 years,” the expert said.

According to Chuvilin, there are fields in Russia where methane from gas hydrates can begin to be produced in the next 10 years, and this will be quite promising. “In some gas fields in the north of Western Siberia, when traditional gas reservoirs are depleted, it is possible to develop overlying horizons where gas can be in hydrated form. This is possible in the next decade, everything will depend on the cost of energy resources,” the agency’s interlocutor concluded.