It is impossible to imagine modern life without such important resources as oil and gas. For humanity, they play a crucial role. Energy is spent on heating the home and cooking. In ancient times, the main sources of energy were the labor of people and livestock, and wood was used for heating homes and cooking. Gradually, manual labor was replaced by machines, and wood by coal. But now, in the fuel and energy industry, oil and gas have supplanted traditional coal and wood. In addition, oil refining products are widely used : gasoline, kerosene, fuel oil.
According to scientists, oil reserves are huge, but non-renewable. Conventional oil is being replaced by so-called shale oil in the markets and in the economic sectors of most countries. What is it and why is it so “unusual”?
Energy resources, their role in the modern world
Gas is one of the most important energy resources. The leading countries in its production are the USA (more than 20% of the world reserves) and Russia (more than 17%).
Gas is widely used in industry and in everyday life. The main advantages of gas:
- With complete combustion, it does not leave behind ash.
- Easy to light and adjust flame size.
- Thanks to the developed transportation system, the consumer receives fuel in the shortest possible time.
- The use of gas in the heating system can significantly reduce utility costs.
- Modern gas boilers allow you to leave the room for a long time, while maintaining heat.
- When burned, very few harmful substances are released into the environment compared to firewood, coal, and oil.
Gas is used in many industries. In metallurgy and mechanical engineering, the energy resource is used as fuel for air heaters, blast furnaces. This increases the productivity of the equipment and improves the quality of products.
On cars, gas perfectly replaces gasoline. This significantly reduces fuel costs, many times reduces emissions of harmful substances into the atmosphere.
The leading role in the economy of most developed and developing countries is oil production. "Black gold", as it is called, lies mainly at a depth of 3-5 km. It is an oily combustible liquid in composition. In its natural form, oil is not used due to increased explosion and fire hazard. Therefore, the first thing they send her to the oil refinery.
The leading country in oil reserves and production is Venezuela (more than 17% of the global reserves). Saudi Arabia (about 16%) and Canada (10%) give way to it. Russia takes 6th place in this list (6%).
Oil refining products and their application:
- Kerosene - aviation and automobile fuel. In addition, kerosene lamps are very popular.
- Car gasoline.
- Fuel oil - used as boiler fuel.
- Bitumen and tar - the main area of application - road works. When gravel and sand are combined, asphalt is obtained.
- Raw hydrocarbons for plastics, rubber, etc.
Unconventional oil
Shale oil production occupies a special place in the development of energy resources. What is its feature? Shale oil is oil produced from oil shale by thermal processes:
- Pyrolysis - heating the formation at temperatures up to 900 degrees Celsius.
- Hydrogenation - the addition of hydrogen to an organic compound. The reaction proceeds at a temperature of about 400 degrees Celsius and a catalyst is used (copper, nickel, platinum).
- Thermal exposure - heating the formation to 80 degrees Celsius and its further sedimentation, which allows you to relatively quickly get the desired resin.
Shale oil reserves were discovered back in the century before last. But the attempts to develop them ended in failure. The fact is that in ordinary oil fields the net percentage of “black gold” ranges from only 1 to 3. The richest deposits are located in shale rocks. Getting this treasure is much more difficult than "ordinary" oil. A breakthrough in shale oil production occurred when horizontal drilling was undertaken (for reference, vertical drilling was mainly used in oil production).
Shale oil is an independent type of fuel, but its refined products are also used. They are used in all industries, as well as conventional oil.
Oil progress
Shale oil in the world has made a real revolution. The main country where huge volumes of its production are achieved is the USA. The second place is taken by Russia. Brazil, Australia, Morocco - these states also boast large reserves of oil shale. It is called “unconventional oil” and the question often arises of how shale oil is extracted, and what is its “unconventionality”.
Methods of producing "unusual" oil:
- Directly from the reservoir. The technology for the production of shale oil is that horizontal wells are drilled and a huge amount of water with an admixture of sand and chemical components is pumped into them. This creates hydraulic fracturing (fracking). From the resulting cracks, oil flows into special reservoirs. Sand is used as a link: it does not allow cracks to close.
- Kerogen mining. This method is much more complicated, since kerogen is contained directly in oil shale and can only be obtained by heat treatment. The technology is as follows: the reservoir is heated to a certain temperature, with the help of an agent the desired substance is displaced and rises to the surface, and the rock is cooled. Then the process is repeated.
Production Features
Shale oil is a breakthrough in the oil and gas industry, but at the same time, production is due to high cost. At the moment, the main production method is hydraulic fracturing. The advantages of this method:
- In difficult conditions of bedding (formation, etc.), drilling with vertical (traditional) wells is dangerous by lateral fractures. In this case, it is advisable to use horizontal wells.
- When drilling with horizontal wells , much less pressure is created on the rocks than with vertical wells. The crack formed using special technologies will retain its shape and direction, which will make it possible to obtain much more oil.
The main disadvantages:
- The solution, which is used to break the oil reservoir, contains a huge amount of harmful substances that are harmful to humans and the environment.
- The water used in this method significantly reduces its supply in the world. For some countries, this is becoming a global threat.
Consequences of shale oil production
When developing “extraordinary” oil fields by horizontal drilling with subsequent fracturing, irreversible consequences arise in the environmental situation. The main problems encountered in oil production:
- When processing shale, a huge amount of carbon dioxide is released into the atmosphere. As a result, the greenhouse effect, climate change.
- Drilling wells and their subsequent blasting leads to the destruction of the earth's crust, earthquakes in places of production.
- Used chemical solutions poison the soil. There is a high probability that chemical components can get into the water supply system of the village. That is why in some countries (France, Switzerland, etc.) this method is prohibited.
- Huge reserves of fresh water are needed in the development of deposits, which are becoming less and less on the planet.
Stocks of “extraordinary black gold” in Russia
As mentioned above, the bulk of oil shale production is in the United States. But Russia has the largest reserves (more than 20% of world reserves). In terms of shale gas reserves, Russia occupies an honorable 9th place, behind China.
Shale oil in Russia is not as popular as, for example, in the United States, despite the huge deposits. One of the main deposits is located in the Siberian region (Bazhenov suite), but, according to geologists, there is not enough data to develop this huge field.
Shale oil is not extracted in Russia because of its high cost, and there is no great need for this. There are enough reserves of ordinary oil, which will last for several decades, subject to several factors:
- Accurate assessment of field reserves.
- When developing deposits, apply such a mining technology in which the fossil is most fully extracted.
- Geological exploration uses modern methods and technologies to accurately assess reserves and their occurrence sites.
The experience of other countries
In China, shale oil is undoubtedly a promising energy resource. The main reserves of the field are located where there is an acute problem of water shortage. Then the method of extraction of oil and gas reserves of carbon dioxide was successfully applied. The process takes place at low temperatures (up to 40 degrees Celsius). This method is applicable for processing raw materials with a low hydrocarbon content.
Australia currently has more than 100 oil fields that are being successfully developed and, according to scientists, the reserves will last for several decades, or even more.
Other mining methods: advantages, disadvantages
Shale oil is an alternative to conventional oil. Reserves of "extraordinary black gold", according to scientists, are much larger than the reserves of "traditional" oil. But the cost of production is quite high. To begin development of the field, you need accurate geological exploration data.
When developing a field, the question arises of reducing water consumption when using the fracturing method. Canadian scientists have developed anhydrous fracturing technology. To do this, instead of water, liquefied propane in the form of a thick gel is pumped into the reservoir. Its advantage is that inside the formation it completely dissolves and comes to the surface together with the produced gas. This method is the most economical and can significantly reduce the impact on the environment and on humans. The main disadvantage is increased explosion hazard.
Another method of anhydrous rupture is the use of foam. The crack is filled with a gel solution with nitrogen or carbon dioxide. The resulting foam squeezes the solution from the reservoir and allows you to get a high content of hydrocarbons.
The use of anhydrous fracturing is a huge leap in solving the problem of lack of fresh water. In addition, these methods are the least harmful to the environment, which is an important factor.
But for the application of a particular method, accurate data on the place of occurrence of the reservoir, its structure are necessary. Using computer modeling, you can track the possible consequences when using these methods and, if necessary, adjust the data.