Test Drive Alternatives: PART 1 - Gas Industry
In the 70s, Wilhelm Maybach experimented with various designs of internal combustion engines, changed mechanisms and thought about the most suitable alloys for the production of individual parts. He often wonders which of the then known combustible substances would be most suitable for use in heat engines.
In the 70s, Wilhelm Maybach experimented with various designs of internal combustion engines, changed mechanisms and thought about the most suitable alloys for the production of individual parts. He often wonders which of the then known combustible substances would be most suitable for use in heat engines.
In 1875, when he was an employee of the Gasmotorenfabrik Deutz, Wilhelm Maybach decided to test whether he could run a gas engine on liquid fuel - more precisely, on gasoline. It occurred to him to check what would happen if he closed the gas cock and instead placed a piece of cloth soaked in gasoline in front of the intake manifold. The engine does not stop, but continues to work until it “sucks” all the liquid from the tissue. This is how the idea of the first improvised "carburetor" was born, and after the creation of the car, gasoline became the main fuel for it.
I am telling this story to remind you that before gasoline appeared as an alternative to fuel, the first engines used gas as fuel. Then it was about the use of (lighting) gas for lighting, obtained by methods not known today, but by processing coal. The engine, invented by the Swiss Isaac de Rivak, the first "naturally aspirated" (uncompressed) industrial-grade Ethylene Lenoir engine since 1862, and the classic four-stroke unit created by Otto a little later, run on gas.
Here it is necessary to mention the difference between natural gas and liquefied petroleum gas. Natural gas contains 70 to 98% methane, with the rest being higher organic and inorganic gases such as ethane, propane and butane, carbon monoxide and others. Oil also contains gases in varying proportions, but these gases are released through fractional distillation or are produced by some side processes in refineries. Gas fields are very different - pure gas or "dry" (that is, containing mainly methane) and "wet" (containing methane, ethane, propane, some other heavier gases, and even "gasoline" - light liquid, very valuable fractions). The types of oils are also different, and the concentration of gases in them can be either lower or higher. Fields are often combined - gas rises above oil and acts as a "gas cap". The composition of the “cap” and the main oil field includes the substances mentioned above, and various fractions, figuratively speaking, “flow” into each other. The methane used as a vehicle fuel "comes" from natural gas, and the propane-butane mixture we know comes from both natural gas fields and oil fields. About 6% of the world's natural gas is produced from coal deposits, which are often accompanied by gas deposits.
Propane-butane appears on the scene in a somewhat paradoxical way. In 1911, an outraged American client of an oil company instructed his friend, the famous chemist Dr. Snelling, to find out the reasons for the mysterious event. The reason for the customer's indignation is that the customer is surprised to find out that half of the filling station's tank has just been filled. Ford She disappeared by unknown means during a short trip to his house. The tank does not flow out of nowhere ... After many experiments, Dr. Snelling discovered that the reason for the mystery was the high content of propane and butane gases in the fuel, and soon after that he developed the first practical methods of distilling them. It is because of these fundamental advances that Dr. Snelling is now considered the "father" of the industry.
Much earlier, about 3000 years ago, shepherds discovered a "flaming spring" on Mount Paranas in Greece. Later, a temple with flaming columns was built on this "sacred" place, and the oracle Delphius recited his prayers in front of the majestic colossus, causing people to feel a sense of reconciliation, fear and admiration. Today, some of that romance is lost because we know that the source of the flame is methane (CH4) flowing from cracks in rocks associated with the depths of the gas fields. There are similar fires in many places in Iraq, Iran and Azerbaijan off the coast of the Caspian Sea, which have also been burning for centuries and have long been known as the "Eternal Flames of Persia."
Many years later, the Chinese also used gases from the fields, but with a very pragmatic purpose - to heat large boilers with sea water and extract salt from it. In 1785, the British created a method for producing methane from coal (which was used in the first internal combustion engines), and in the early twentieth century, the German chemists Kekule and Stradonitz patented a process for producing heavier liquid fuel from it.
In 1881, William Hart drilled the first gas well in the American city of Fredonia. Hart watched the bubbles rising to the surface of the water in a nearby bay for a long time and decided to dig a hole from the ground to the proposed gas field. At a depth of nine meters below the surface, he reached a vein from which gas gushed out, which he later captured, and his newly formed Fredonia Gas Light Company became a pioneer in the gas business. However, despite Hart's breakthrough, the lighting gas used in the XNUMXth century was extracted mainly from coal by the method described above - mainly due to the lack of potential for developing technologies for transporting natural gas from fields.
However, the first commercial oil production was already a fact then. Their history began in the USA in 1859, and the idea was to use the extracted oil to distill kerosene for lighting and oils for steam engines. Even then, people were faced with the destructive power of natural gas, compressed for thousands of years in the bowels of the earth. The pioneers of Edwin Drake's group almost died during the first impromptu drilling near Titusville, Pennsylvania, when gas leaked from the breach, a giant fire broke out, which carried away all the equipment. Today, the exploitation of oil and gas fields is accompanied by a system of special measures to block the free flow of combustible gas, but fires and explosions are not uncommon. However, the same gas is in many cases used as a kind of “pump” that pushes oil to the surface, and when its pressure drops, oilmen begin to look for and use other methods to extract “black gold”.
The world of hydrocarbon gases
In 1885, four years after William Hart's first gas drilling, another American, Robert Bunsen, invented a device that later became known as the "Bunsen burner". The invention serves to dose and mix gas and air in a suitable proportion, which can then be used for safe combustion - it is this burner that today is the basis of modern oxygen nozzles for stoves and heating appliances. Bunsen's invention opened up new possibilities for the use of natural gas, but although the first gas pipeline was built as early as 1891, blue fuel did not gain commercial importance until World War II.
It was during the war that sufficiently reliable methods of cutting and welding were created, which made it possible to build safe metal gas pipelines. Thousands of kilometers of them were built in America after the war, and the pipeline from Libya to Italy was built in the 60s. Large deposits of natural gas have also been discovered in the Netherlands. These two facts explain the better infrastructure for using compressed natural gas (CNG) and liquefied petroleum gas (LPG) as a vehicle fuel in these two countries. The enormous strategic importance that natural gas is beginning to acquire is confirmed by the following fact - when Reagan decided to destroy the "Evil Empire" in the 80s, he vetoed the supply of high-tech equipment for the construction of a gas pipeline from the USSR to Europe. To compensate for European needs, the construction of a gas pipeline from the Norwegian sector of the North Sea to mainland Europe is accelerating, and the USSR is hanging. At the time, gas exports were the main source of hard currency for the Soviet Union, and the severe shortages resulting from the Reagan measures soon led to the well-known historical events of the early 90s.
Today, democratic Russia is a major supplier of natural gas to Germany's energy needs and a major global player in this area. The importance of natural gas began to grow after the two oil crises of the 70s, and today it is one of the main energy resources of geostrategic importance. Currently, natural gas is the cheapest fuel for heating, is used as a feedstock in the chemical industry, for electricity generation, for household appliances, and its "cousin" propane can even be found in deodorant bottles as a deodorant. substitute for ozone-depleting fluorine compounds. The consumption of natural gas is constantly growing, and the gas pipeline network is getting longer. As for the infrastructure built so far for the use of this fuel in cars, everything is far behind.
We have already told you about the strange decisions that the Japanese made in the production of much-needed and scarce fuel during the Second World War, and also mentioned the program for the production of synthetic gasoline in Germany. However, little is known about the fact that in the lean war years in Germany there were quite real cars running on ... wood! In this case, this is not a return to the good old steam engine, but internal combustion engines, originally designed to run on gasoline. In fact, the idea is not very complicated, but requires the use of a bulky, heavy and dangerous gas generator system. Coal, charcoal or just wood is placed in a special and not very complex power plant. At its bottom, they burn in the absence of oxygen, and in conditions of high temperature and humidity, a gas is released containing carbon monoxide, hydrogen and methane. It is then cooled, cleaned, and fed by a fan into the engine's intake manifolds for use as fuel. Of course, the drivers of these machines performed the complex and difficult functions of firefighters - the boiler had to be periodically charged and cleaned, and the smoking machines really looked a bit like steam locomotives.
Today, gas exploration requires some of the world's most sophisticated technology, and the extraction of natural gas and oil is one of the biggest challenges facing science and technology. This fact is especially true in the US, where more and more unconventional methods are being used to "suck" gas left in old or abandoned fields, as well as to extract so-called "tight" gas. According to scientists, it will now take twice as much drilling to produce gas at the level of technology in 1985. The efficiency of the methods is greatly increased, and the weight of the equipment has been reduced by 75%. Increasingly sophisticated computer programs are being used to analyze data from gravimeters, seismic technologies and laser satellites, from which three-dimensional computerized maps of reservoirs are created. So-called 4D images have also been created, thanks to which it is possible to visualize the forms and movements of deposits over time. However, state-of-the-art facilities remain for offshore natural gas production—only a fraction of human progress in this area—global positioning systems for drilling, ultra-deep drilling, ocean floor pipelines, and liquefied clearance systems. carbon monoxide and sand.
Refining oil to produce high-quality gasoline is a much more complex task than refining gases. On the other hand, transporting gas by sea is much more costly and complex. LPG tankers are quite complex in design, but LNG carriers are a stunning creation. Butane liquefies at -2 degrees, while propane liquefies at -42 degrees or relatively low pressure. However, it takes -165 degrees to liquefy methane! Consequently, the construction of LPG tankers requires simpler compressor stations than for natural gas and tanks that are designed to withstand not particularly high pressures of 20-25 bar. In contrast, liquefied natural gas tankers are equipped with continuous cooling systems and super-insulated tanks - in fact, these colossi are the world's largest cryogenic refrigerators. However, part of the gas manages to "leave" these installations, but another system immediately captures it and feeds it into the ship's engine cylinders.
For the above reasons, it is quite understandable that already in 1927 the technology allowed the first propane-butane tanks to survive. This is the work of the Dutch-English Shell, which at that time was already a giant company. Her boss Kessler is an advanced man and an experimenter who has long dreamed of using in some way the huge amount of gas that has so far leaked into the atmosphere or burned down in oil refineries. On his idea and initiative, the first offshore vessel with a carrying capacity of 4700 tons was created to transport hydrocarbon gases with exotic-looking and impressive dimensions above deck tanks.
However, another thirty-two years are needed to build the first Methane Pioneer methane carrier, built by order of the gas company Constock International Methane Limited. Shell, which already has a stable infrastructure for the production and distribution of LPG, bought this company, and very soon two more huge tankers were built - Shell began to develop the liquefied natural gas business. When the inhabitants of the English island of Conway, where the company is building methane storage facilities, realize what is actually stored and transported to their island, they are shocked and scared, thinking (and rightly so) that the ships are just giant bombs. Then the problem of safety was really relevant, but today tankers for the transport of liquefied methane are extremely safe and are not only one of the safest, but also one of the most environmentally friendly sea vessels - incomparably safer for the environment than oil tankers. The largest customer of the tanker fleet is Japan, which has practically no local energy sources, and the construction of gas pipelines to the island is a very difficult undertaking. Japan also has the largest "park" of gas vehicles. The main suppliers of liquefied natural gas (LNG) today are the United States, Oman and Qatar, Canada.
Recently, the business of producing liquid hydrocarbons from natural gas has become increasingly popular. This is mainly ultra-clean diesel fuel synthesized from methane, and this industry is expected to develop at an accelerated pace in the future. For example, Bush's energy policy requires the use of local energy sources, and Alaska has large deposits of natural gas. These processes are stimulated by relatively high oil prices, which create prerequisites for the development of expensive technologies - GTL (Gas-to-Liquids) is just one of them.
Basically, GTL is not a new technology. It was created in the 20s by the German chemists Franz Fischer and Hans Tropsch, mentioned in previous issues as part of their synthetic program. However, in contrast to the destructive hydrogenation of coal, the processes of joining light molecules into longer bonds take place here. South Africa has been producing such fuel on an industrial scale since the 50s. However, interest in them has grown in recent years in search of new opportunities to reduce harmful fuel emissions in the United States. Major oil companies such as BP, ChevronTexaco, Conoco, ExxonMobil, Rentech, Sasol and Royal Dutch/Shell are spending huge sums on developing GTL-related technologies, and as a result of these developments, political and social aspects are increasingly being discussed in the face of incentives. taxes on clean fuel consumers. These fuels will allow many consumers of diesel fuel to replace it with more environmentally friendly and will reduce the cost to car companies to meet new levels of harmful emissions set by law. Recent in-depth testing shows that GTL fuels reduce carbon monoxide by 90%, hydrocarbons by 63% and soot by 23% without the need for diesel particulate filters. In addition, the low-sulfur nature of this fuel allows the use of additional catalysts that can further reduce vehicle emissions.
An important advantage of GTL fuel is that it can be used directly in diesel engines without any modifications to the units. They can also be mixed with fuels containing 30 to 60 ppm sulfur. Unlike natural gas and liquefied petroleum gases, there is no need to modify the existing transport infrastructure to transport liquid fuels. According to Rentech President Denis Yakubson, this type of fuel could ideally complement the eco-friendly economic potential of diesel engines, and Shell is currently building a large $ 22,3 billion plant in Qatar with a design capacity of XNUMX million liters of synthetic fuel per day. ... The biggest problem with these fuels stems from the huge investment required in new facilities and the typically expensive production process.
Biogas
However, the source of methane is not only underground deposits. In 1808 Humphry Davy experimented with straw placed in a vacuum retort and produced a biogas containing mainly methane, carbon dioxide, hydrogen and nitrogen. Daniel Defoe also talks about biogas in his novel about the "lost island". However, the history of this idea is even older - in the 1776th century, Jan Baptita Van Helmont believed that combustible gases could be obtained from the decomposition of organic substances, and Count Alexander Volta (the creator of the battery) also came to similar conclusions in 1859. The first biogas plant began operating in Bombay and was established in the same year that Edwin Drake produced the first successful oil drilling. An Indian plant processes faeces and supplies gas for street lamps.
It will take a long time before the chemical processes in the production of biogas are thoroughly understood and studied. This became possible only in the 30s of the XX century and is the result of a leap in the development of microbiology. It turns out that this process is caused by anaerobic bacteria, which are one of the oldest life forms on Earth. They “grind” organic matter in an anaerobic environment (aerobic decomposition requires a lot of oxygen and generates heat). Such processes also occur naturally in swamps, marshes, paddy fields, covered lagoons, etc.
Modern biogas production systems are becoming more popular in some countries, and Sweden is a leader in both biogas production and vehicles adapted to run on it. Synthesis units use specially designed biogenerators, relatively inexpensive and simple devices that create a suitable environment for bacteria, which, depending on their type, “work” most efficiently at temperatures ranging from 40 to 60 degrees. The end products of biogas plants, in addition to gas, also contain compounds rich in ammonia, phosphorus and other elements suitable for use in agriculture as soil fertilizers.
