Almost every resident of our country knows what gasoline is. Even children know this school age, however, all this knowledge is too general. Many people only know that the car needs this fluid in order to drive. But what gasoline is made from, what types there are and how it is obtained - few know all this. Let's try to understand these issues.
What is gasoline?
This is the fuel used to run engines. internal combustion, which most cars are equipped with (there are also cars with electric motors where this fuel is not used). In more detail, it is a mixture of certain light hydrocarbons that have a boiling point in the range of 30-200 degrees Celsius. The density of the fuel is 0.7 g/cm3, and its thermal conductivity is 10500 kcal/kg. These are its main characteristics. There are also such parameters as brand and detonation resistance, but more on that a little later.
Gasoline production technology
Oil is the main raw material for the production of this fuel. It is obtained through petroleum distillation, hydrocracking and further aromatization. Special gasolines are additionally purified from unnecessary components in the composition, and are also enriched with various additives, which are popularly called additives.
There are also cases where other hydrocarbon raw materials are used in the production of gasoline. For example, in Estonia during the existence of the USSR, gasoline was made from oil shale, therefore, it can be produced from coking and semi-coking resins with subsequent purification. Synthesis gas can also be a raw material for the production of this fuel (synthesis gas is the conversion of methane and gasification of coal) - there are corresponding technologies using cogazin and syntin.
Classic technology
Most often, when producing gasoline, standard technology is used at oil refineries, which involves mixing certain components:
- Light naphtha is straight-run gasoline (naphtha is a light fraction of hydrocarbons that is obtained during the distillation of oil).
- Isomerisate (naphtha isomerization product).
- Reformate (reformed product of the heavy fraction of hydrocarbons).
- Gasoline obtained as a result of the decomposition of heavy fractions of primary distillation.
- Hydrocracking gasoline (a product of the decomposition of heavy fractions that has survived vacuum and atmospheric distillation).
- Special additives.
The easiest way to get automobile gasoline- select light fractions during oil distillation and increase the octane number by adding a large number of additives.
Varieties
Now you understand what gasoline is - it is the easiest liquid fraction oil obtained from the distillation of this black raw material. The standard hydrocarbon composition of this fuel includes molecules with a length of C 5 to C 10. However, it is important to understand that there are different types this fuel, therefore the composition and properties of gasoline may differ significantly. It all depends on how exactly the fuel was obtained. After all, it can be produced not only through crude distillation of oil. It is even obtained from heavy fractions of oil (the so-called cracked gasoline) and from associated gas.
Gas gasoline
It is intuitively clear that this product is obtained by processing petroleum gas. It contains saturated hydrocarbons, the number of carbon atoms in which is more than three. There are stable and unstable gas gasoline. Stable can be light or heavy - it is used in petrochemicals as a raw material. Most often used in organic synthesis plants, but can also be used to make motor gasoline. In this case, it is simply mixed with other types of fuel.
Cracking gasoline
It is obtained by additional distillation of petroleum products. On average, distillation of oil produces only 10-20% of gasoline. To increase this number, heavy fractions of oil are heated, which makes it possible to break the large molecules in their composition into small ones. This is cracking, although the technological process in this case is described primitively. Using this technology, when distilling oil, it is possible to obtain up to 70% of fuel from the volume of raw materials processed.
Pyrolysis
This technology is very similar to cracking. There is only one difference - more high temperature heating the feedstock (700-800 degrees). Pyrolysis allows you to increase the yield of gasoline from raw materials to 85%.
Octane number and knock resistance
One of the most important characteristics gasoline is its resistance to detonation, which is determined by the octane number. There are different brands of fuel: AI-92, AI-95, AI-98. All these brands of gasoline are obtained by mixing components that were obtained as a result of different technological processes. Naturally, there is a GOST that regulates the proportions of mixing components, which ultimately makes it possible to obtain fuel with a certain octane number. Thus, the AI-98 gasoline brand has an octane number of 98, the AI-95 brand has an octane number of 95.
In this case, the octane number of 95 indicates that the gasoline contains 95% isooctane and 5% heptane. For different engine standards (Euro-4, Euro-5) it is recommended to use one or another gasoline. The difference between them lies in the degree of compression at which fuel detonation (micro-explosion) occurs.
After the primary distillation of oil, gasoline with an octane number of 70 is usually obtained. Such fuel is low-grade and unnecessary, so various additives are added to it to increase the octane number (the most common is tetraethyl lead, but other anti-knock agents can also be used).
Yes, by mixing certain components and additive additives produce the desired fuel with a specific detonation number. Manufacturers of cars based on Euro 5 engines recommend pouring a certain fuel into the gas tank. AI-95 gasoline is indicated specifically for such engines. Euro-4 engines work well with fuel with a lower octane number - 92. If AI-92 gasoline is poured into a Euro-5 engine, so-called premature detonation is possible during its operation. It happens because the gasoline in the cylinders ignites prematurely, causing the engine to run slightly incorrectly. This may result in loss of traction and increased gas consumption. If you add AI-95 fuel to a Euro-4 standard engine, then gasoline explosions may occur late, which is also bad. Therefore, it is advisable to use only the gasoline recommended by the engine manufacturer.
Determination of octane number
There are different ways to determine octane number. The easiest way is to measure it using a portable device. It is enough to insert it into a container with fuel, and it will show the octane number.
The second method is research. It is carried out using a single-piston engine without simulating strenuous driving. The motor method can also be used. It uses a single-piston engine that simulates hard driving.
Application
Gasoline is primarily used to run internal combustion engines. It can also be used as a solvent. There is aviation and motor gasoline. The first, as the name suggests, is used in aviation, and its main difference is its higher octane number. It contains much more light fractions.
Motor gasoline can be divided into 2 categories: summer and winter. The latter is produced with a higher content of hydrocarbons, and its boiling point is lower. This is necessary so that at subzero temperatures it effectively explodes in the combustion chamber of the engine. This fuel is mainly sold in the northern regions of Russia, and in the southern regions it appears at gas stations in late autumn and does not disappear until early spring.
Conclusion
Now you know what gasoline is made from, and, most importantly, how. Oil has been and remains the main raw material for the production of fuel, so humanity’s need for it is now simply enormous. So far, there are no serious (except for uranium) competitors among energy resources that could compete with oil. As for the gasoline itself, it is being improved every year, which affects the resistance to detonation. Car engines are also being improved, and today there are engines running on gasoline with an octane rating of 100 and 102. However, the bulk of modern engines consume AI-92 fuel (older power plants) or AI-95 (new), but many new cars are equipped with engines that work better with AI-98 gasoline.
Good old gasoline is the most popular flammable liquid for cars on our planet. Every day, about 800 million thirsty cars consume 7 billion liters of this liquid, and the inexhaustible thirst is constantly growing. Keeping the world's gas pipelines safe, with highly flammable liquids flowing through them, is an incredibly complex and potentially risky business. This requires a combination of brilliant engineering skills, chemical skill, as well as endurance and patience. So what is gasoline made from?
Texas, USA. You could be forgiven for thinking of this hot, lifeless, windswept area as rural outback. But in fact, it is one of the richest places in the world, since Texas is the birthplace of the American oil industry.
Oil has been extracted here since 1894. But the real oil boom began in 1901, when the Lucas Gusher company tripled oil production in the United States at once.
Since then, almost 60 billion barrels have been pumped from Texas soil and if oil companies correctly calculated, then there is approximately another 10 billion in reserve that remains to be mined. The viscous, foul-smelling, black liquid that attracts them is crude oil, the raw material for the production of gasoline. It was formed from the remains of small marine plants and animals during the Permian period. 250 million years later, under the influence of heat and pressure, they have become one of the world's most important sources of energy. This is black gold, Texas tea, the best there is. She smells like rotten eggs, but also money.
On a hot, humid Texas morning, a rig crew is preparing to drill another well. More than two thousand new wells are drilled in Texas every month, all pumping more than nine hundred thousand barrels of crude oil per day. To maintain oil production at this level, producers like Occidental Petroleum drill an average of one new well every day. For the workers who work here, hot, noisy, hard work is completely normal. “I really love this job and have been doing it for 11 years,” says one of them. “We take pride in our work at the tower. We're like one big family."
But the team faces the labor-intensive task of extracting oil. In this area, the so-called Permian basin, crude oil lies at a depth of up to four kilometers, sandwiched rocks, about 542 million years old. In order to get to it, the tower uses huge motors to lower the side with a diamond bit deep into the ground.
Friction causes the temperature to rise greatly, so water is constantly pumped into the pipe under high pressure to cool the drill head. The water then pushes the drill cuttings to the surface in the form of drilling fluid.
It's a noisy, dangerous job. Workers must maintain the correct pressure on the drill bit. If it is too small, the rig will not drill, and if it is too large, it will break. In addition, workers must be constantly alert to the threat of gas releases that can cause catastrophic explosions. “Working on a drilling rig is really dangerous, we have to be extremely careful in this kind of work.” While drilling, the crew must constantly extend new nine-meter drill pipe using a huge five-ton automatic pipe wrench, the so-called “iron assistant”. Since the drill head goes deep by about 5 meters per hour, this hard work must be repeated every two hours throughout the day. If, in the end, they are lucky, they will discover an oil source.
First, oil under pressure is forced through small holes in the finished pipe and rushes to the surface. But this natural pressure does not last long, so pumping pumps are used to keep the oil flowing continuously pumping unit or "head-nodding donkey." The circular motion of the rotating flywheel is converted into a vertical one, and it, like a huge metal syringe, draws oil to the surface. Scattered across the desert, these calm, persistent, head-nodding burros are harvesting the black gold of Texas.
But these oil fields are many kilometers away from where crude oil is needed.
So a series of pumps pump it into the pipeline and send it on a long journey of thousands of kilometers to its destination, in another part of the United States - to the citadel of shiny silver pipes - the city of Baytown.
It is located less than fifty kilometers from Houston, and looks like a futuristic set from the movie Blade Runner. This is the only, largest oil refinery in the United States. It covers an area of more than ten square kilometers. With metal pipes over eight thousand kilometers long and can process more than 562 thousand barrels of crude oil daily. Not only is it incredibly hot, but the noise is so deafening that the 4,000 workers here wear out more than a million ear protectors a year.
The enterprise is so huge that it absorbs not only local products, but also processes oil coming from all over the world. To meet the needs of Baytown, huge 300-meter ships arrive here at specially designed piers. Over 20 such powerful ships arrive every month. Each unloads about three million barrels of oil from its huge holds, the same amount as each rig in Texas produces in three and a half days.
But all this oil needs to be refined, because it is really unprocessed, raw. It cannot be used as car fuel. There is a laboratory located in the center of the oil refinery. It controls the process of converting crude oil into usable products.
It is crude oil and in this state it is not very useful. If you pour it into the tank, then, unfortunately, you will not be able to go anywhere.
The fact is that crude oil consists of a mixture of hydrocarbons, each of which has a different number of carbon atoms. They have different weights. The lightest is propane, and the heaviest is used to make asphalt.
Producing gasoline from this mixture is a difficult task, and this requires complex chemical processes. In the largest part of the plant, in a structure as shiny as the moon and tall as a cathedral, crude oil is separated. It is heated to temperatures above 370 degrees Celsius and pumped into the base of the tower. Steam rises from there, as if from a boiler. During heat treatment, molecules condense. First, the heaviest ones, bitumen, at the base. The lighter molecules found in gasoline and jet fuel continue to rise until they too liquefy and can be pumped out.
But the difficulty in producing different types of gasoline is that it now becomes an unusually explosive liquid to deal with. Well, of course, it's gasoline's ability to explode that makes it so useful. To make sure it's explosive enough, workers carefully take the sample to a lab for analysis. From each tank with a volume of 191 liters of crude oil, the following is produced:
88 liters of gasoline
48 liters of diesel fuel
about 26 liters of jet fuel and fuel oil
approximately 7 liters of propane
another 32 liters of other products such as lubricants and plastic.
This plant produces enough gasoline every day to fly a car to the moon and back 770 times. The laboratory makes a final analysis of all products produced at the refinery, and if it does not meet customer requirements, it does not leave the refinery gates. Fuel is checked by pouring it into gasoline evaluation devices.
One of them is an outdated but strong engine, which is tested for resistance to detonation. The engine produces a knocking sound when the fuel spontaneously ignites as it is compressed in the engine cylinder. The cause of premature combustion is too much heptane and not enough octane in the mixture. By increasing the octane percentage, the mixture can be improved until the knocking noise stops.
The lab then sends the data back to the main refinery to correct any mixing errors and produce a perfect blend.
When distillation is complete at the plant, some of the five hundred valves are opened and the gasoline flows through an underground pipeline that carries it to numerous terminals like the one in south Houston.
From here it is pumped into huge fuel tankers for transport along the road.
But filling up a tanker truck is more complicated than simply filling up your car. This can be a dangerous activity and the tanker driver must be very careful and attentive. Carrying hundreds of liters of quickly evaporating cargo means that the driver must strictly adhere to safety measures. An error when loading and unloading a tank can lead to an explosion, so it should not allow dangerous accidents. The metal body is capable of generating sparks from static electricity, so first a wire is attached to ground the trailer, and also probes are connected on top of each compartment to control overflow. To avoid flammable vapors, attach a second vapor recovery hose. It pumps out any leaks that might otherwise enter the atmosphere. Only after installing and connecting all these gizmos can the driver connect the hoses and start pumping gasoline.
Every day, more than a million liters of gasoline are safely delivered to local gas stations from this terminal alone. Gasoline, pumped into the gas station's huge tank, is finally ready for consumption. So the next time you fill up your car with gas and are surprised by the price, take some consolation to think about how much work went into making your car's wheels turn.
Gasoline - it’s hard to remember something more familiar to a motorist. Every day, cars burn hundreds of thousands of liters of this fuel, but few car owners have seriously thought about how it is produced, the characteristics of the fuel composition and other aspects.
Some terminology
- Aromatic;
- Olefinic;
- Paraffin and others.
These hydrocarbons have flammable properties. The boiling point of the mixture varies from 33 to 250 °C, which depends on the additives used.
What is gasoline made from?
Gasoline production scheme
Fuel is produced at oil refineries. Myself production process very complex and is divided into several cycles.
Crude oil first enters the plant through pipelines, is pumped into huge tanks, and then settles. Next, oil washing begins - water is added to it, and then it is passed through electric current. As a result, salts settle to the bottom and walls of the tanks.
During subsequent atmospheric-vacuum distillation, the oil is heated and divided into several types. There are 2 stages of processing:
- Vacuum;
- Thermal.
Upon completion of the primary refining process, catalytic reforming begins, during which gasoline is further purified and fractions of 92-grade, 95-grade and 98-grade gasoline are extracted.
Photo: aif.ru
This process, also called recycling, includes 2 main stages:
- Cracking – purification of oil from sulfur impurities;
- Reforming is giving a substance an octane number.
Video: How gasoline is made from oil. Just something complicated
At the end of these stages, fuel quality control is carried out, which takes several hours.
It is noteworthy that domestic factories (in the majority) produce 240 liters of gasoline from 1 ton of oil. The rest comes from gas, fuel oil and aviation fuel.
What is octane number
This phrase is known to many people, but not everyone knows what exactly this term means and why it is so important.
Octane number- this is the ability of fuel (including gasoline) to resist spontaneous combustion under pressure. In other words, its detonation resistance.
During engine operation, the piston compresses the fuel-air mixture (compression stroke). At this moment, when the finished mixture is under pressure, it may spontaneously ignite even before the spark plug has given a spark. People call this phenomenon in one word - . A characteristic feature detonation is noise in the engine - a metallic ringing.
Therefore, the higher the octane number, the higher the ability of the fuel to resist detonation.
Gasoline labeling
At gas stations you can find a variety of names, not excluding those that are most familiar to most motorists. Typically, gasoline is marked with the letters “A” and “AI”. Their decoding:
- “A” - this designation indicates that;
- “AI” - the letter “I” means the method by which the octane number was determined.
There are 2 ways to determine the octane number - research (AI) and motor (AM).
Research method - it is determined by testing the fuel on a single cylinder power plant, subject to a variable compression ratio, a crankshaft speed of 600 rpm, an ignition timing of 13° and an air (intake) temperature of 52 °C. These conditions are similar to light and medium loads.
Motor method - its determination is carried out on a similar installation, but other conditions are different. The air temperature (intake) is 149 °C, the crankshaft speed is 900 rpm, and the ignition timing is variable. This mode is similar to high loads - driving uphill, running the engine under load, etc.
Consequently, the number of AM is always lower than AI, and the difference in readings indicates the sensitivity of the fuel to the operation of the power unit in different modes. It is noteworthy that in some countries in the West, the octane number is defined as the average between the “AM” and “AI” values. In the Russian Federation, only a higher “AI” value is indicated, which can be seen at all gas stations.
Gasoline brands
The following designations are most often found at domestic gas stations:
- Gasoline AI-98. Different Unlike AI-95, which is produced in accordance with GOST, the 98th is produced in accordance with TU 38.401-58-122-95, as well as TU 38.401-58-127-95. In the production of this brand of gasoline, the use of alkyl lead antiknock agents is prohibited. This high-octane gasoline is produced using a number of components - toluene, isopentane, isooctane and alkyl gasoline.
- Extra AI-95 – gasoline improved quality, which is achieved by using anti-knock additives. Produced from distillate raw materials, catalytic cracking gasoline, with the addition of isoparaffin elements (aromatic) and gas gasoline. It contains no lead, which ensures high quality gasoline.
- AI-95 - the main difference from Extra AI-95 is the concentration of lead, which is 30% higher;
- AI-93 - divided into 2 categories: leaded and unleaded. Leaded fuel is produced on the basis of catalytic reformed gasoline (mild mode) with the addition of toluene and alkyl gasoline, as well as a butane-butylene fraction. Unleaded is produced from the same catalytic reforming gasoline (hard mode), with the addition of butane-butylene fraction, alkyl gasoline and isopentane;
- AI-92 is the most common medium-quality gasoline on the market, containing anti-knock additives. Maximum density – 0.77 g/cmA-923. Can be either leaded or unleaded;
- AI-91 – differs in the content of anti-knock additives. This is unleaded gasoline with an unstandardized density and a certain percentage of lead in the composition;
- A-80 - the composition of this gasoline is similar to that of AI-92. Maximum density – 0.755g/cmA-803;
- A-76 - usually used in agriculture. Leaded and unleaded A-76 is produced with non-standardized density. It contains additives of various types (anti-oxidation and anti-knock), straight-run gasoline, as well as final, pyrolysis and cracking (thermal and catalytic).
Video: AI-92 or AI-95? Acceleration to 100 km and fuel consumption on Mazda Demio (Ford Festiva Mini Wagon)
What kind of gasoline should I use?
Many people are looking for the answer to this question so as not to inadvertently harm the engine. In this case, everything is simple - the fuel requirements are indicated in the operating instructions for a particular car, and are also duplicated on the back of the gas tank flap. If the manufacturer indicated AI-95 as the recommended fuel, then refuel with 92 only at your own peril and risk. However, it is worth remembering that both the octane number and the brand of fuel may be indicated in the manual and on the label.
Also, different types of gasoline may be recorded in the manual. For example:
- AI-92 – acceptable;
- AI-95 – recommended;
- AI-98 - to improve performance.
As you can see, you only need to fill the tank with fuel recommended by the car manufacturer. However, using gasoline with a higher octane number will not cause any harm to the engine. After all, the higher the octane number, the slower speed combustion and greater fuel efficiency, which has a beneficial effect on engine performance, efficiency and other aspects. As a rule, the increase in power and efficiency reaches 7%. In addition, modern cars are equipped with ECUs that take into account the quality of the fuel and its octane number, adjusting the settings.
This means that AI-95 must be filled into the tank of a modern car with an atmospheric engine at a high-quality gas station. As a last resort, AI-92 is allowed. You can also focus on the compression ratio - if it is below 10 units, you can fill in AI-92. If higher - only 95th.
As for turbocharged engines, the recommended fuel for them is AI-98 or Extra AI-95, but not AI-92.
Is it possible to mix gasoline?
Many people ask this question. In general, nothing catastrophic will happen from mixing fuel with different octane numbers, but only if you mix the recommended gasoline with a higher octane number. For example, the 92 recommended for a car should be mixed with 95. However, there is no need to downgrade. It is also worth remembering that the density of gasoline with different octane numbers differs, so its mixing may not occur at all - fuel with a higher octane number will simply end up at the top of the tank, and with a lower one at the bottom.
Gasoline has become scarce - many motorists are wondering what else they can invent to save it, or even replace it. Ideas are put forward and disputes arise. It turns out, however, that not all of their participants clearly understand what modern motor gasoline is. We decided to devote our today’s lecture, prepared from literary sources, to this topic.
Gasoline is known to be obtained from petroleum.. This natural liquid basically consists of only two chemical elements- carbon (84-87%) and hydrogen (12-14%). But they combine with each other in a great variety of combinations, forming substances that we call hydrocarbons. A mixture of various liquid hydrocarbons is oil.
If you heat oil at atmospheric pressure, then the lightest hydrocarbons evaporate from it first, and as the temperature rises, heavier and heavier ones evaporate. By condensing them separately, we obtain different fractions; those that boiled away in the temperature range from 35° to 205°C are considered gasoline (for comparison, condensate obtained at temperatures from 150 to 315°C is called kerosene, from 150 to 360°C - diesel fuel).
However, this method (called direct distillation) produces very little gasoline - only 10-15% of the distilled oil. A huge fleet of cars that require this type of fuel cannot be “fed” this way. Therefore, the bulk of commercial gasoline is produced as a result of the so-called secondary oil refining processes, which include thermal and catalytic cracking, platforming, reforming, hydro-reforming and many more. These processes are complex, but they are united by a common goal - to break up large and complex molecules of heavy hydrocarbons into smaller and lighter ones, forming gasoline. Without going into the technological details of secondary processing, we will only note that it allows not only to increase the yield of gasoline from oil several times, but also ensures a higher quality of the product compared to direct distillation.
So, light petroleum fractions, which can serve as fuel for carburetor automobile engines, have been obtained and from them it is necessary to prepare commercial gasoline with certain properties. We will talk about these properties.
Heat of combustion. The chemical energy contained in any fuel, when burned, is released in the form of heat, which can be converted into mechanical work. This is exactly what happens in the engines of our cars. Specific heat combustion of motor gasoline is a fairly constant value, each
A kilogram of this fuel emits approximately 10,600 kilocalories - a serious charge of energy, which is sufficient, for example, to lift a weight of 4.5 thousand tons to a meter height.
Octane number. In a mixture of gasoline vapor and air, which is compressed in the combustion chamber of the engine, the flame spreads at a speed of 1500-2500 m/s. If the compression is too great, peroxides are formed in the combustible mixture, and combustion becomes explosive. This is detonation, well known to motorists, which leads to emergency engine failure.
Gasoline's resistance to detonation is measured by its octane number. It is determined by comparing the gasoline under study with a special reference fuel consisting of a mixture of isooctane (its octane number is taken as 100) and heptane (taken as zero). What percentage of isooctane is in the mixture on which the engine operates in the same way as on this gasoline is the octane number of this gasoline.
Of course, the motor installation in this experiment is special, exploratory, and all experimental conditions are standardized. If we talk about driving under normal operating conditions, then it would be incorrect to attribute detonation only to the properties of gasoline itself. The danger of its occurrence increases due to the following: large opening of the throttle valve in the carburetor, lean fuel mixture, increased ignition timing, increased engine temperature, decreased crankshaft speed, large number carbon deposits in the cylinders, unfavorable atmospheric conditions (high temperature and low air humidity, increased barometric pressure). By the way, the combination of these very factors often leads the driver to erroneous conclusions, they say, bad gasoline was poured at the gas station, or vice versa - this is how good the engine is, it does not detonate even on low-octane gasoline.
Here it should be noted that the octane number of gasoline is determined primarily by which fractions, which hydrocarbons predominate in it. High-octane components include alkylbenzene (a mixture of aromatic hydrocarbons), toluene, isooctane, alkylate (a mixture of isoparaffin hydrocarbons).
However, you can increase the octane number of gasoline by adding a special additive - an anti-knock agent. Until recently, tetraethyl lead (TEL) or tetramethyl lead was very widely used for this purpose, preparing the well-known leaded gasoline. But when they are used, lead oxide is deposited on the spark plugs, valves and walls of the combustion chamber, and this is harmful to the engine. The main thing, however, in another thermal power plant is a strong poison; its presence in the exhaust gases poisons the atmosphere and harms people and all living things in general. Therefore, now everywhere, including in our country, they are abandoning ethyl liquid, despite the associated increase in the cost of gasoline
The fractional composition objectively characterizes the volatility of motor fuel. The lower the temperature at which 10% of gasoline is distilled, the better its starting properties, but the greater the risk of vapor locks appearing in the fuel supply line, as well as carburetor icing. The relatively low distillation temperature of 50% gasoline indicates its good volatility in operating conditions, but again also its ability to cause icing. Finally, a high distillation temperature of 90% indicates that gasoline contains a lot of heavy fractions, which contribute to the dilution of the oil in the crankcase and the associated deterioration of lubrication of engine parts.
We just mentioned vapor lock and carburetor icing. The first, obviously, does not require much explanation, since this phenomenon is familiar to every car enthusiast. It should only be noted that for commercial gasoline supplied to gas stations during the cold season (from October to March inclusive), the distillation temperature of 10% of the total volume is 55°C, and in the summer - 70°C. That is why “winter” gasoline, stored until the hot season, can cause quite a lot of vapor locks when driving, especially in traffic jams.
As for carburetor icing, it is worth saying a few words about it. Evaporation of a liquid is always associated with the absorption of heat and cooling of the evaporation zone. The same goes for the carburetor. One of the real experiments showed that at an air temperature of +7°C, two minutes after starting the engine, the throttle valve cooled down to -14°C; If there are no protective measures, ice formation in such a case is inevitable. The main one of these measures is the intake of air into the air filter from the exhaust pipe area (“winter” position of the intake). It should be borne in mind that the conditions in which carburetor icing poses a real danger are as follows: air temperature from -2° to +10°C, relative humidity - 70-100%. The conclusion is simple: although many carburetors are liquid heated, and a special anti-icing additive is introduced into modern commercial gasolines, with the advent of cold weather you must not miss the moment and promptly switch the air intake to the winter position.
Resin formation. Over time, chemical reactions can occur in liquid hydrocarbons to form sticky, rubber-like substances called resins. They are very harmful because they clog the carburetor and deposit on the intake valve stems. The susceptibility of a particular commercial gasoline to tar formation may be different; it depends on the fraction and chemical composition mixtures, but there are also general conditions external character that should be kept in mind. Let's list them. The more gasoline comes into contact with air, the faster tars form in it, so tarring occurs much faster in a car tank than in a completely filled and sealed canister. Heat and light, as well as the presence of water, accelerate the precipitation of resins. The material from which the container is made also plays a role: copper and lead enhance resin formation.
Hygroscopicity. In principle, water does not mix with pure gasoline; it sinks to the bottom of the vessel and remains there in the form of a separate layer. But a very small amount of it (60-100 grams per ton of gasoline) still goes into solution. In aromatic hydrocarbons (benzene, toluene), the solubility of water is 8-10 times greater, therefore, those commercial gasolines that contain such components may contain a small, but still noticeable amount of water. This is not a hindrance for fuel combustion, but if the solution is saturated, then under certain conditions (say, when the temperature drops) water can separate from the fuel and cause considerable trouble - form ice crystals in the metering elements of the carburetor or contribute to their oxidation. Therefore, gasoline should be protected as much as possible from water getting into it.
Of course, today we have not mentioned everything that concerns gasoline and is of well-known practical interest for motorists. “Behind the scenes” we still have topics that deserve a separate discussion: about evaluation, labeling, features and assortment of commercial gasolines. But a few words must be said here about the composition of the two most common brands today.
Gasoline A-76. The basis for it is a product of catalytic reforming or catalytic cracking, into which thermally cracked or straight distilled gasoline is mixed. To obtain the desired octane number, either ethyl liquid or high-octane hydrocarbon components are added to this mixture.
Gasoline AI-93 in leaded version is a mild-mode catalytic reforming product (75-80%), to which toluene (10-15%), alkylbenzene (8-10%) and ethyl liquid are added. Unleaded gasoline AI-93 is obtained on the basis of a hard-mode catalytic reforming product (70-75%) with the addition of alkylbenzene (25-28%) and butane-butylene fraction (5-7%).
We all know what gasoline fuel is, but not everyone understands how, from what, and under what conditions it is produced.
Methods for producing a gasoline mixture are a very long process that requires a certain engineering skill, perfect knowledge of chemistry and iron patience.
How gasoline is made from oil in factories
Result: all loans increased by 40% in six months, the cost of equipment is also around 40–50%, plus sanctions, and taxes, unfortunately, are not falling at all.
Current gasoline prices are quite reasonable In 2015, gasoline prices rose by 4.8%, and diesel prices by 3.4%. The average cost for the period of January 2016 per liter was 34.89 rubles, and the price for diesel fuel was 35.54 rubles per liter. Oil continues to fall in price, dropping to $34 per barrel.
What should be done in such a situation? Either raise prices in order to give at least some of the money for loans, or give the banks the deposits, factories and production facilities for which they were taken, which is unacceptable.
What's the solution? In order to retail prices fuel prices have stopped growing; the cost of wholesale quantities needs to go down. But manufacturers are not ready for such a step.
Be that as it may, we have to wait for better times with hope, no matter how long this situation lasts. After all, the fact that our beloved cars always want to eat cannot be changed, except by switching to a bicycle.
Now we know how gasoline is made from oil. We understand the complexity of the procedure for its extraction, all the calculations and time, how many people and their labor are spent to ensure that our iron horse is always well-fed.
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