1900 The last of the outgoing XNUMXth century. A century marked by an enormous number of significant technical inventions and practical innovations. Time, which gave a significant impetus to the evolution of mankind, with which it is still impossible to measure any period. People rightly welcome the new century with a new self-confidence, and the technical exhibition in Paris is a kind of showcase of universal upsurge. This exhibition is by far the largest event of its kind ...

FIRST PART

Among the many important and not very valuable technical inventions and innovations in Paris, one of the first real engines of Rudolf Diesel can be found - already sophisticated enough to be demonstrated to the public.

Here we will not retell the mysterious halo around this man who created the fundamental creation of the modern world, we will save you the explanation of the genius of the technical idea underlying his project, but instead we will pay attention to the fuel with which Rudolph Diesel drives the Paris ". The fuel is actually ... peanut butter!

At that time, many already assumed the great importance of cars for the future of humanity, but none of the many brilliant creators of the era knew what would actually power the engines of the cars of the future. Many scientists at the time believed that alcohol was the most suitable fuel for Otto's engine. This misconception belongs to Rudolf Diesel and the people around him, who firmly believe that they have become a powerful new source of livelihood for farmers around the world. As we already know from history, such development is initially hindered.

With the development of the gasoline engine and the gradual entry of the car into everyday life (to be precise, in the life of Americans, because in Europe the car for many years was the privilege of a small segment of the super-rich), the oil managed to establish its position. Refineries are increasingly being forced to comply with the demands of their new largest consumer, which complicates refining processes to improve gasoline production. Back in 1914, thermal cracking was invented, which significantly increased the amount of gasoline produced per unit of oil. Work on it continues, but at some point the refineries are clogged with an excessive amount of heavier distillate fuel released as a residual product from gasoline production. As mentioned, in addition to the well-known large deposits in the United States and Russia, which were major players in the oil arena at the turn of the century, black gold has already been discovered in Persia, Venezuela and Mexico. With more and more drilling operations being carried out in Texas and California, the world is clearly moving towards a phase of oil saturation. The surplus of the distillate fuel just mentioned turns out to be a suitable fuel for the diesel engines that have entered industry and everyday life everywhere. Some of them (for example, those on the Caspian ships of the Nobel brothers who bought a license for a diesel engine) will start using crude oil as fuel, other slow-speed diesel engines will be content with much heavier fuel oil, and others will use oil pumped directly into coal furnaces of steam boilers.

The combination of these circumstances quite clearly describes the energy picture of that time and explains why the diesel engine no longer needs agricultural products for fuel. The truth is that at the time, animal and especially vegetable fats were not only insanely expensive compared to cheap oil, but also not quite suitable for use in a diesel engine.

In principle, vegetable fats and oils can be used in the newly invented high compression machine because they have an organic composition similar to that of the diesel fraction, but on the other hand, have a much higher molecular weight. These similarities are not surprising given the fact that the most common theory of the origin of oil is organic and that fat itself is one of the substances that entered the bowels of the earth and became part of the organic matter that gave rise to "black gold".

Mysterious constructor

No, we are not talking about Rudolph Diesel here. It will be about the no less mysterious aura of another German, which began to hover around the diesel engine after the death of its inventor - an aura that belongs no less exotic than Diesel itself, to a person engaged in the improvement of his ingenious discovery and made the greatest contribution to the creation of a diesel engine after its creator. The company, founded by the same man, is still the leader in the production of diesel machines specifically designed to work with vegetable oils. The name of this man is Ludwig Elsbet, and his life ended a few years ago, when he was exactly 90 years old.

A year before the outbreak of World War I, little Ludwig was born on a small farm near the equally small town of Salz in Lower Franconia. Like most of the characters in our stories, he loved technology from an early age and learned how to repair the agricultural machinery he most often deals with - a fate very similar to that of Henry Ford. Ludwig received his degree in mechanical engineering and in 1937 began working at the Junkers factories in Dessau as head of the research department for gasoline engines. By the way, it was in this department that the first gasoline direct injection systems were developed, used on German combat aircraft, but that's another story. At the end of the war, the Allies broke the back of the German economy, dropping tons of aerial bombs on important industrial centers - as a result of several bombings of Dessau, only heaps of rubble remained from the Junkers factories, and Ludwig Ellsbet and his large family managed to escape. Russian army escaping on bicycles. Immediately after the war, he began working for the Salzinger automobile company, first assembling tractors with aircraft engines that had survived the war, and then assembling cars from recycled military equipment. Jeep.

In 1951, the tech world was struck by the Ellisbett X-frame unveiled at the Berlin International Motor Show. However, the main reason for the enthusiasm of the specialists is not in the frame, but in the engine presented by Elsbet. The magazine "Auto, Motor und Sport" writes with surprise. The Elsbeth machine with its four-cylinder two-stroke light alloy radial diesel engine attracted the most interest at the show. The design is both very light and simple. It is truly revolutionary and can rightfully be called the technical masterpiece of the German car industry. Elsbeth's company, meanwhile, files for bankruptcy, and he buys most of it and becomes an independent manufacturer of two-stroke diesel engines. In 1956, he developed an "internally cooled" diesel engine, creating the first of its kind without a water jacket and circulating cooling streams, in which all heat, except for radiation emitted as heat loss, is transferred to the exhaust gas.

In 1959, Elsbeth moved to MAN, improving the so-called “M-process” and thereby more than doubling the company's market presence. Back in 1973, Ellsbett developed special injectors and created a direct injection diesel engine based on an in-line six-cylinder engine. BMW... The engine showed excellent performance, but BMW and Bosch, which are involved in the implementation of the fuel system, were unable to translate this project into a production reality. Obviously, Bosch was influenced by the opinion of many experts of the time, who stated that it was technically impossible to create a reliable diesel engine for a direct injection vehicle at this stage. Eventually BMW abandoned this technology and it was only 15 years later that Ferdinand Piech imposed this concept on Audi - redesigned Elsbet, but completely new and created without the help of Bosch.

In parallel with this fundamental development, Elsbet has created many other interesting technologies, such as the so-called "Duoterm Combustion Piston", in which combustion is insulated from the cylinder walls and, along with special double bottom pistons, leads to significant fuel savings. Together with Nixdorf, Ellsbet developed the first electronically controlled injection system, as well as the "integrated injection" system, which is the direct predecessor of modern common rail and "unit injector" systems.

At first glance, Ellsbet's comprehensive biography just presented has no place in this narrative, and seems to deviate significantly from the main topic of fuel. However, Ellsbet is such a unique part of modern technological progress, and his inventions are so important that it would be unthinkable to miss his name and contribution. It is on the basis of his ideas that he and the designers of his company Elsbett create systems that are absolutely applicable in practice for feeding diesel engines with vegetable oils. Please note - not with biodiesel, but with vegetable oils. Elsbett develops both engines for agricultural machinery that work exclusively with vegetable oils, as well as additional installation systems that allow the use of vegetable oils as a fuel for standard diesel engines. Special diesel engines have special nozzles, heaters, modified glow plugs and a number of other specialized devices that allow using vegetable oils as fuel without problems.

From the deep fryer - straight into the container

To begin with, it is worth clarifying that a diesel engine can run on ordinary vegetable oil. Therefore, we will first introduce you to it, and then to a secondary fuel known as biodiesel and obtained through a relatively simple chemical process based on vegetable oils as raw materials.

One of the main problems with vegetable oils is their significantly higher molecular weight and significantly higher density than petroleum diesel, so they need to be preheated with special devices to prepare them to pass through them. special nozzles that take care of their correct spraying.

This all sounds pretty simple, but don't be too quick to jump to positive conclusions. The point is that there is no authoritative source regarding alternative fuels for diesel engines that can categorically speak out for or against the suitability of these fluids as fuel. Many cars in America and Europe use Elsbett systems, and two or three more companies make them for use in other vehicle engines, but no one categorically says that using an alternative to diesel is a never-ending feast. On the contrary, a number of sources of information and participants in discussion sites note that they had problems with corrosion of fuel pumps, problems with wear of piston rings and cylinders, as well as the decomposition of some polymer elements of various systems and engine assemblies. Because fuel does not evaporate or burn completely in cold weather, deposits form on injectors and cylinder heads, which in turn leads to reduced power, lower efficiency, increased emissions and reduced engine life.

The Elsbett system and some other vegetable oil systems have two fuel tanks. The engine is started on regular diesel or biodiesel fuel, and the vegetable oil tank is heated to 700 C. When the temperature is reached, the engine switches to vegetable oil, and the reverse procedure is carried out a few minutes before stopping.

Although the properties of many vegetable oils are similar to those of diesel fuels, most of them cannot become rare enough even with significant heating and lead to the aforementioned accumulation of deposits in fuel tanks, clogged filters, poor ignition and deposits. pure carbon in the form of soot on piston rings as a result of pyrolysis, for oil dilution and other similar negative effects.

In 1997, American Joshua Tykle toured America in his diesel van, filling it with used vegetable oil from fryers at roadside restaurants such as KFC and McDonalds. The media paid special attention to this transition, but more as a curiosity, and many found this undertaking a convenient target for ridicule ... However, in 2007, such ridicule became increasingly irrelevant, work on the creation of technology for engines operating with such fuel. absorbs more and more investment, and there are already a large number of construction and agricultural machinery in the United States that uses vegetable oil as fuel.

Biodiesel

From everything that has been said so far, it is clear that in fact the use of engines using chemically untreated and not subjected to any other treatments other than filtering vegetable oils can hardly find a permanent place in the sun. The use of biodiesel as a fuel seems to be much more promising.

In practice, the same vegetable oils are used as raw materials for its production, but are mostly processed through a chemical process known as transesterification. Biodiesel has a higher cetane number than petroleum diesel fuel - its value ranges from 45,8 to 56,9 depending on the feedstock for its production. However, modern technologies at refineries have already made it possible to bring petroleum diesel fuel closer to biodiesel by this criterion, reaching the number from 50 to 55 cetane number.

A number of studies on biodiesel properties began during World War II, like most other alternative forms of energy, but at this early stage it did not reach the level of an industrially significant factor. With the first oil crises of the 70s, little has changed, and biodiesel has been talked about again, and plants for its production began to appear only in the early 90s.

However, unlike ethanol, which is mainly used in the United States and Brazil, Europe plays a leading role in biodiesel technology, which for a number of reasons is its main producer and consumer as fuel for cars. These reasons are of a purely regional nature - the diesel engine is much more relevant for Europeans, and local agricultural production is a prerequisite for obtaining more fatty raw materials than alcohol. In the United States, on the other hand, they use significantly less biodiesel produced in their territory to power buses, trucks and agricultural machinery. At the same time, however, Americans value the role of biodiesel as an ideal and quick way to increase the cetane level in diesel fuel produced in American refineries - biodiesel is a safe fuel and can be used in any proportion in a mixture with petroleum diesel fuel.

It is generally known that foreign diesel fuel is a rather low-quality fuel with a high sulfur content and a low cetane number, since the cracking and reforming processes are aimed at obtaining higher-octane gasoline fractions.

Химия

What makes biodiesel an interesting and profitable energy source is that it can be produced from many different plant sources such as soy, canola, coconuts, flax, hemp and sunflower seeds, peanuts, and many others. Each of these raw materials is widely distributed in different parts of the world - soybeans in America, rapeseed in Europe, and coconut in Malaysia. The common denominator of all these raw materials is the high content of vegetable fats. The fats in question, also known as triacylglycerols, are organic compounds and, like fuel oils, contain hydrogen, carbon and oxygen (in this case in large quantities). The shape of the glycerol molecule is similar to the letter E, to which three fatty acid chains are attached like a skeleton - precisely because the molecules that make up them are quite large, the use of vegetable oils as a fuel source is so difficult. Biodiesel is produced in a transesterification process in which the structure in question reacts with alcohol (ethyl or methyl), resulting in the long fatty acids being separated from the base structure and converted into three separate ester molecules (plus the base structure molecules). The end products of the process are glycerin and fatty acid methyl (or ethyl) ester, since esters are the main component of biodiesel.

The main advantages of biodiesel over diesel fuel are that it is produced from renewable sources, does not depend on political whims and shocks, does not contain sulfur and polycyclic aromatic hydrocarbons, burns better than diesel fuel, and emits less harmful emissions. (carbon monoxide and hydrocarbons) due to the presence of oxygen in its chemical composition. In addition, biodiesel is biodegradable, that is, in the presence of certain conditions and bacteria, it can completely decompose without harmful effects on the environment. It is also assumed that this fuel is neutral with respect to carbon dioxide - the oxide consumed during photosynthesis of raw materials for its production is equal to emissions from fuel combustion. Much more complex is the issue of fuel prices, which largely depend on the size and form of government subsidies for agriculture and biodiesel plants.

Europe

Europe is the largest producer of biodiesel, and European cars are used by the majority of vehicles that use this fuel. Production is concentrated in countries where prices for this type of fuel are formed due to significant tax breaks, and the largest of these is Germany. This is followed by France, Italy, Austria, Sweden and the United Kingdom, but biodiesel production has recently increased in some Eastern European countries such as Poland and the Czech Republic. Since 1992, the production of raw materials for biodiesel production has increased significantly after the European Commission established mechanisms to regulate the use of land for non-food crops exclusively for energy production and co-financed the first esterification plants. According to these mechanisms, the share of biofuels added to the main non-oil fuel should reach 5,75% in 2010. In general, the desire of the European Union to seek, albeit very slowly, a way out of the situation of constantly rising prices for oil fuel and, ultimately, their complete replacement with similar "local production" is impressive. The same proposal also establishes a legal framework to stimulate production through certain reduced tax rates on biofuels.

There are currently more than 1600 biodiesel filling stations in Germany, which is why discussions about problems with its use are especially noisy and fierce. However, despite the criticism, it is a fact that the Germans maintain moralistic and determined environmental views, and it cannot be denied that over 1 million hectares of agricultural land are currently planted with crops grown for biofuel production in this country.

As strange as it sounds, the main consumers of biodiesel are oil companies and petroleum product companies, followed by public transport and taxis. Oil companies view biodiesel as an additive to the main fuel oil they produce for very good reasons. First of all, it has excellent lubricating properties, and since oil companies have recently had to produce more and more diesel fuel with low sulfur content and poor lubricating properties, biodiesel is an ideal alternative to compensate for this deficiency - especially since this biofuel does not contain sulfur compounds. Among the largest consumers of biodiesel are oil companies TotalFinaElf, Agip and Shell, the latter recently adding some of its diesel fuel and 5% of synthetic diesel fuel produced from natural gas to its diesel fuel. Looking ahead, it should be noted that the most likely alternative to the current classic petroleum fuels is a mixture of similar substances, obtained in different ways. In America, BP and Chevron started selling biodiesel, while consumption is growing at an incredible pace.

While the benefits of biodiesel sound like poetry, and plant-based fuels are heavily touted by environmentalists as an alternative to oil depletion, biodiesel also has many problems - from the reluctance of engines to accept it without resistance to severe infrastructure shortages. its production, distribution and consumption. Some manufacturers have even backed down in this regard and still do not offer biodiesel-powered food systems, seeking the excuse for unregulated and unclear exhaust emission limit values. In practice, the real problem is that they do not take on the XNUMX% guarantees regarding the fuel system elements due to the still different quality of biodiesel offered on the network.

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