How fuel is obtained from algae. Eco-friendly fuel. What are the costs associated with growing algae?

Promising raw materials for biofuel are marine microalgae, which do not require any clean water, no land.

Researchers have determined the composition of biofuel derived from microalgae Spirulina platensis, using mass spectrometry high resolution. Scientists have studied two fractions of biofuel, which are obtained after the algae mass is processed using a special method. In addition, they showed that biofuel has little in common with oil in composition, but it has something in common with brilliant green - the same one that can be bought at any pharmacy. The work was done by a group of scientists from Skoltech, the V. L. Talrose Institute of Energy Problems of Chemical Physics of the Russian Academy of Sciences, the N. M. Emanuel Institute of Biochemical Physics of the Russian Academy of Sciences, the Joint Institute of High Temperatures of the Russian Academy of Sciences, Moscow State University and the Moscow Institute of Physics and Technology. The study was published in the European Journal of Mass Spectrometry. A press release from the Moscow Institute of Physics and Technology talks about it briefly.

Algae as a salvation for the environment

Biofuels, as an alternative source of energy, are of particular interest to study because they could help solve problems such as depletion of oil reserves and global warming. Unlike oil, biofuels are made from renewable natural resources and release fewer greenhouse gases when burned. Brazil, for example, already meets 40% of its needs using biofuels.

Agricultural crops and other plants are used as raw materials for biofuel. However, in this case it is necessary to borrow fertile land, which could feed people instead. A promising raw material for biofuel is marine microalgae, which requires neither clean water nor land. Algae actively absorb carbon dioxide, which means their use is really useful for reducing the greenhouse effect. Microalgae fuels are called third-generation biofuels, and active developments are currently underway to produce them.

Biofuel recipe

If we know the composition of biofuel, we can improve the process of its production. The initial techniques for producing fuel from algal mass were energetically unprofitable, since a lot of energy was spent on drying algae, which contains a lot of water.

For commercial use, a new, larger effective method. And such a method was invented - this is the so-called hydrothermal liquefaction: wet biomass is heated to a temperature of more than 300℃, compressed with a pressure of 200 atmospheres and fuel is obtained at the output. Approximately the same principle operates in nature, when under the influence of high temperatures and high pressure Oil is formed in the bowels of the Earth, only in a reactor this happens faster. The result is two fractions: liquid biofuel and a thick mass that remains in the reactor. These are mixtures consisting of thousands of individual components and mass spectrometry is best suited to determine their composition.

Mass spectrometry

Mass spectrometry is a research method that can be used to determine the composition of a substance. The method is based on the fact that in an electric and/or magnetic field, different compounds behave differently, depending on their mass and charge m/z ratio. The output is a mass spectrum - a graph with intensity peaks, where each peak corresponds to its own m/z value.

Mass spectra of the liquid fraction (top) and solid fraction (bottom)

Scientists used mass spectrometry to study biofuel derived from algae Spirulina platensis. During the hydrothermal liquefaction process, all substances with a boiling point less than 300 degrees leave the reactor in the form of gas and are cooled in a special container. Thus, a liquid fraction is obtained, and a solid fraction remains in the reactor. Mass spectrometric analysis showed that both fractions contain the most substances that contain N and N 2, but the components of the solid fraction are more diverse and differ in properties from the components of the liquid fraction. The substances found in biofuels had nothing in common with substances found in conventional crude oil, although they are flammable. Mass spectrometry allows you to find out only the molecular formulas of substances (for example, C 18 H 35 N 2). To obtain some information about the structure of molecules, the researchers used the method of replacing hydrogen with deuterium.

Replacing hydrogen with deuterium

Before you launch molecules into a mass analyzer, they need to be charged, otherwise the electromagnetic field will not affect them. Ordinary molecules have charge z=0, and the number of protons in them is equal to the number of electrons. And if, for example, a proton (particle with charge +1) is attached to a molecule, then it will become an ion with charge z=1. The process of converting molecules into ions is called ionization. When hydrogen is replaced by deuterium, the mass of the ion* becomes larger and the peak in the spectrum shifts. Based on whether the peak has shifted or not, scientists determine where the hydrogen was located in the molecule. However, not any hydrogen will give up its place to deuterium, or rather, not any place hydrogen will be able to vacate.

In the nucleus of deuterium, or heavy hydrogen, in addition to the proton, there is a neutron, which affects the mass, but not the charge

Before being introduced into the mass analyzer, the sample molecules are ionized. IN in this case Protons were added to neutral compounds and they became positive ions. The attached proton is easily replaced by a deuteron, but it turns out that in some biofuel components the replacement does not occur. Scientists understood this from the intensity of the shifted peak that is obtained during the replacement. In ordinary oil, the shifted peak had the same intensity as the unshifted one, which means that the replacement occurred completely.

In the case of biofuel, the intensity of the shifted peak was five times less. This means that under one peak there are several compounds and not all of them have attached hydrogen, which could be replaced by deuterium. If substances cannot be ionized, then they are already positive ions and are contained in biofuels in this form. These substances are similar to some dyes, such as brilliant green, which is part of brilliant green.

Evgeniy Nikolaev, corresponding member of the Russian Academy of Sciences, professor at Skoltech, scientific adviser The MIPT Laboratory of Ion and Molecular Physics comments: “The study of products of hydrothermal liquefaction of microalgae using mass spectrometry has important to improve the efficiency of biofuel production. Further work should focus on using algae varieties with the highest lipid content and creating such varieties using genetic modification. This way we can select the most efficient feedstock for biofuel from them.”published

Biodiesel is a multicomponent liquid fuel, consisting of methyl or ethyl esters of higher unsaturated and fatty acids obtained by chemical reaction, mainly by esterification vegetable oils(rapeseed, soybean, palm, sunflower, flaxseed, etc.), as well as by transesterification of fats (animal and feed). Recently, new biodiesel production technologies have been developed, such as the processing of plant raw materials with genetically modified microorganisms (at the University of California, together with the LSG company, USA, they developed a genetically modified strain of the bacterium E. Coli, which has the ability to convert cellulose and hemicelluloses into biodiesel), the use “waste” vegetable oils, which are collected in restaurants and cafes, production from raw materials of microbial origin, and some others. For example, due to the fact that the resources of vegetable oils obtained from agricultural crops are limited, today extensive research is being carried out all over the world in the use of various - both naturally occurring and newly cultivated special types algae as a promising raw material for biodiesel production.

Biodiesel is considered in EU countries as the main renewable liquid biofuel. Its production volume is growing rapidly. The volume of biodiesel production in the world since 2002 (1.2 million tons) reached 18 million tons by 2010 (in 2009 - 14 million tons). According to forecasts, with this trend, by 2020 the volume of biodiesel production in the world will be 100 million tons per year.

The leader in the production and use of biodiesel in Europe is the Federal Republic of Germany - about 3 million tons in 2012 (mainly from rapeseed), with the technical capacity of all plants producing 5 million tons per year. France ranks second: about 2 million tons per year. In total, in Europe, according to EU analytical data for 2013, there are 256 biodiesel production plants in operation. In the EU, since 2008, when the rapeseed crop failure led to a decrease in biodiesel production and, accordingly, an increase in its imports, competition between European and overseas producers of this type of fuel has become relevant. Biodiesel producers from Argentina and Indonesia, thanks to significant government subsidies, were able to supply it to European markets at a price that is lower than the price of the raw material itself (palm oil). Therefore, in 2012, some European countries, in particular Germany, adopted a number of anti-dumping laws and increased import duties on the import of biodiesel from these countries.

In the US, biodiesel is produced primarily from soybean oil (it makes up 30% of all feedstocks used in the world to produce biodiesel, with canola and palm oil, with minor amounts of other oils, sharing the remaining 70%). Biodiesel in the USA is used in vehicles and as heating fuel. The share of liquid biofuels in the US market is more than 5%. Due to the fact that the technologies for obtaining the oils listed above are high-cost, a search is underway for cheaper plants. Thus, jatropha (the euphorbia family) and camelina (the cabbage family) have already begun to be used successfully.

In the last few years, biodiesel producers have been paying more and more attention to castor beans (lat. Rнcinus), a plant of the Euphorbiaceae family. It is an oilseed medicinal and ornamental garden plant. Castor oil is obtained from castor beans using cold pressing, which has one of the highest cetane numbers among vegetable oils.

The management of the Brazilian agricultural concern Agrakonzern SLG has set a goal of producing castor oil using new technologies at a cost of $50 US per barrel (for comparison: a barrel of soybean oil costs $170).

The yield of biodiesel from various oilseeds is (l/ha): from rapeseed - 1100, from sunflower - 690, from soybeans - 400. In Germany, for example, rapeseed oil is mainly used for the production of biodiesel. Rapeseed - unpretentious culture, and it can be grown on land taken out of production. It increases the biological activity and structure of the soil, cleans it of nitrogen. Biodiesel in Germany is cheaper than regular diesel fuel, despite the fact that there is a tax on biodiesel fuel. The cultivation of rapeseed is subsidized by the federal budget.

Let us consider in general terms the main technology for the production of biodiesel today by the esterification of vegetable oils.

Any vegetable oil is a mixture of triglycerides (esters) combined with a glycerol molecule with trihydric alcohol (C 3 H 8 O 3). It is glycerin that gives viscosity and density to vegetable oil. To obtain biodiesel, it is necessary to remove glycerin, replacing it with alcohol. This process ( chemical reaction the formation of esters by the interaction of acids and alcohols) is called esterification.

The feedstock (oil) is supplied to the esterification unit, where methanol (at a ratio with oil from 1:4 to 1:20) and a catalyst solution (sodium or potassium hydroxides, or sodium methoxide, ranging from 0.3 to 1.5) are simultaneously supplied % of the volume of all processed raw materials) to carry out the esterification process. At the end of the process, as a result of settling, the mixture obtained in the esterification unit is divided into two layers: the upper one is a mixture of methyl ethers and methanol, the lower one is glycerin (with a small amount of methanol). Upper layer is sent to the methanol stripping unit, from which the methanol is returned to the esterification unit, and the remaining crude product - methyl ether (biodiesel) - enters sequentially into the washing unit and drying chamber.

The esterification process lasts from 20 minutes. up to several hours at operating temperature 65°C.

The by-product obtained from the bottom layer by distilling methanol into the esterification unit - crude glycerin - is widely used in the pharmaceutical and paint and varnish industries. By the way, glycerin can also be processed into biofuel - bioethanol with a yield of up to 95%.

Esterification technologies without a catalyst and under supercritical conditions are also used. In the first option, instead of catalysts, a special solvent is introduced into the esterification reactor: tetrahydrofuran. Due to this, the solubility of the components in the reactor increases, the process temperature decreases to 30°C, and the process time is reduced to 10 minutes. its duration. The mixture is clearly separated into an ether and glycerin layer. There is no need to wash and dry the product.

In the second option, the esterification process is carried out at high temperatures of up to 400°C and pressures of up to 80 atm, which also makes it possible to do without catalysts and reduces the duration of the process in the reactor to 5 minutes.

Biodiesel (methyl ester) calorific value an average of 37.6 MJ/kg and a high cetane number (51-58) in comparison with petroleum diesel fuel, for which it is 50-52. And the higher the cetane number, the better the fuel. Biodiesel can be used both in pure form and as an additive to diesel fuel.

Table 1. Comparison of the main indicators of standards
biodiesel in the EU and diesel fuel in the Russian Federation

Biodiesel is biologically harmless. When released into water, it does not harm aquatic flora and fauna. It undergoes almost complete biological decomposition in water or soil (up to 99% within a month), therefore, when using biodiesel on river and sea vessels, pollution of the planet’s water resources can be significantly minimized. When burning biodiesel, significantly less CO 2 is released into the atmosphere than when burning conventional fuels. In addition, the advantages of biodiesel over them are obvious due to the low characteristics of combustion products: carbon monoxide, residual particles, soot and, most importantly, polycyclic aromatic hydrocarbons (known carcinogens). Biodiesel, compared to mineral diesel fuel, contains almost no sulfur (10.0 mg/kg). Therefore, in some countries municipal transport is being switched to biodiesel fuel. , Tests are being carried out on the use of biodiesel as aviation fuel.

Biodiesel has good lubricating properties. It is known that diesel fuel loses its lubricating properties when sulfur compounds are removed from it. But biodiesel, despite its low sulfur content, is characterized by good lubricating properties, which is determined by its chemical composition and its oxygen content. Due to this property, the service life of the engine increases: while the engine is running, it is simultaneously lubricated moving parts and fuel pump.

Biodiesel has a high flash point (above 100°C), which makes it safer than conventional diesel fuel.

Of course, biodiesel also has a number of disadvantages. First of all, it has low frost resistance, so in cold weather it must be warmed up or diluted with ordinary diesel fuel. In undiluted form, biodiesel can damage rubber hoses and gaskets, so they often need to be replaced with products made from higher grades. resistant materials. Biodiesel is not subject to long-term storage. In table Table 1 shows the main indicators of biodiesel standards in Europe and petroleum diesel fuel in Russia.

Bio-oil

Bio-oil is a mixture of liquid hydrocarbons and other organic substances obtained from raw materials of plant or biological origin. Bio-oil is a conventional name, since the hydrocarbon content in it is only 5-10%, and the rest is alcohols, lignins, aldehydes, etc. There are the following thermal or thermochemical methods for producing bio-oil from plant biomass: pyrolysis, gasification, steam cracking, hydrocracking.

As a result of pyrolysis (the process of decomposition of raw materials when heated to 450-550°C in the absence of oxygen), raw materials are converted into coal, as well as liquid and gaseous products. In this case, liquid pyrolysis products can be used as fuel, which last years called "bio-oil", "biomazut" or "pyrolysis liquid". To increase the yield of bio-oil (up to 80% of the total volume of dry raw material at the input), so-called fast pyrolysis is used: the pyrolysis process lasts several seconds at a very high temperature - up to 1000°C. The heat of combustion of bio-oil is 16-19 MJ/kg, which is significantly lower than the heat of combustion of hydrocarbon fuel. In Finland this year, the Finnish energy concern Fortum will, for the first time in the world, build a plant for the production of bio-oil from wood chips using the pyrolysis method; The enterprise's productivity will be 50 thousand tons per year. To produce bio-oil, 600 thousand m 3 of wood will be required annually. Fortum is known in Russia for the construction project from scratch in the city of Nyagan (KhMAO - Yugra) of the first large power plant after the collapse of the USSR (Nyagan State District Power Plant) with a total capacity of 1260 MW.

Bio-oil and bioethanol can also be obtained from waste sugar production- molasses stillage.

Biogasoline

Biogasoline (synthetic gasoline) was produced on an industrial scale back in the 30-40s of the twentieth century in Germany from synthesis gas (Fischer-Tropsch method) during the gasification of fossil coals. The process can also use solid biomass, including wood, instead of coal. But at present, such biogasoline is not produced, despite the fact that biogasoline has important environmental advantages over conventional gasoline, such as the absence of sulfur and nitrogen compounds, as well as heavy metals; in addition, when biogasoline is burned, carcinogenic compounds are not formed; the main reason is the high cost of production.

Vegetable oils

Not everyone knows that the first diesel engine, created by German engineer Rudolf Diesel in 1897, ran on vegetable (peanut) oil.

Vegetable oils (calorific value 33-34 MJ/kg) have been used as motor fuel for quite some time; considerable experience has been accumulated in the use of sunflower, peanut, soybean, corn, rapeseed and other oils. Most wide application received rapeseed oil, since rapeseed is the most highly productive of oilseeds (sunflower is in second place in terms of productivity, soybeans are in third place). Algae can become a new promising source of raw materials for the production of fuel oils, in which the content of oil, similar in composition to known plant ones, reaches 40% of the total mass with significantly higher productivity than the latter. For example, when processing rapeseed into oil, 265 liters of oil can be obtained from 1 acre of arable land per year, and when cultivating algae from 1 acre of water surface, 20 thousand liters of oil per year can be obtained.

Germany is a leader not only in the use of biodiesel, but also in the use of vegetable oils as motor fuel (mainly rapeseed oil). In the United States, soybean oil is predominantly used as a biofuel among all vegetable oils. Seed oil is obtained by conventional pressing (or extraction), in which the raw material is purified from foreign impurities, then mixed with a solvent - extractant (which is used as gasoline, hexane or ethanol) - and stirred for a certain time, after which it is separated from the oil cake. the remaining mixture is separated into solvent, which is returned to the extraction unit, and crude unrefined oil.

The yield of oils when using pressing technology is 28-29%, and when extracting - 40-42% in relation to the original raw material (with an oil content of 45-50%).

Vegetable oils as fuel are characterized by a higher energy density compared to alcohols, but their performance qualities are worse than those of alcohols, in particular: high viscosity and a greater tendency to form soot. Therefore, it is preferable to use vegetable oils mixed with diesel fuel. A mixture of rapeseed oil and diesel fuel is called a biodiesel mixture, or biodite.

BTL (Biomass-to-Liquid)

BTL (Biofuel-to-Liquid) - one of the types of liquid biofuel (calorific value on average 33.5 MJ/kg), innovative technology production of which was developed quite recently, in the 2000s, with the participation of such world-famous companies as Shell, Daimler, Volkswagen, and the innovative company Choren GmbH. The first BTL production plant was built in Freiburg, Germany in 2007. The raw material base of production is more than 70 thousand tons of waste from the woodworking industry, sawmilling and landscaping. Today, BTL technology is considered the most promising for producing liquid biofuel. Any type of solid biomass is suitable for BTL production: wood chips, sawdust, straw, agricultural waste, as well as miscanthus and other fast-growing plantation plants, household waste and much more. Therefore, BTL production does not require raw materials in the form of agricultural products for food use (cereals, oilseeds), unlike the production of bioethanol and biodiesel, and thus does not compete in terms of raw materials Food Industry. To obtain 1 kg of BTL you need from 5 to 10 kg of wood raw materials.

BTL production involves a combination of several long-established processes: pyrolysis, high-temperature flow gasification and Fischer-Tropsch, or MtG (Methanol-to-Gasoline) processes.

At the first stage, dried raw materials (biomass with a moisture content of up to 20%) undergo low-temperature pyrolysis at a temperature of 400-500°C. The output is coal, coke and gas-containing tar. The resin is then burned at a temperature above the melting point of the ash (above 1400°C) in a combustion chamber to produce a gaseous mixture of CO and H2. The remaining ash and coke are returned to the combustion chamber, and the gas passes through a scrubber, purified from chlorine and sulfur, and then Fischer-Tropsch synthesis is performed: with the help of a cobalt catalyst, hydrogen and carbon are combined and after purification the final product is obtained: BTL. BTL does not contain aromatic hydrocarbons and sulfur, it has a high octane number, and its use reduces CO 2 emissions into the atmosphere by up to 90% compared to hydrocarbon fuels.

In recent years, throughout the world, the use of seeded food crops for the production of liquid types Biofuels are considered irrational, since this type of use leads to higher food prices. This is why they began to produce liquid biofuel of the so-called second generation: from seed grasses and different plants, not used in the food industry and cultivated on lands unsuitable for main crops, from algae, from household waste, from fast-growing plantation plants, from woodworking and sawmill waste, from straw. As for wood raw materials, as noted above, there are many different technologies in the world for producing liquid biofuels from cellulose-containing materials. But the cost of producing, for example, bioethanol from such raw materials is twice as high as the cost of producing it from grain... Moreover, in the near future it is unlikely that technologies will be created that will reduce the cost of the process. Therefore, it is difficult to say whether liquid biofuel from cellulose-containing raw materials will be competitive on the market.

According to the author, in Russia the greatest efficiency in the production and use of any type of liquid biofuel obtained from solid biomass can be achieved in the agricultural sector. More than 5 million tons of diesel fuel are burned annually in the Russian agro-industrial complex. At agricultural enterprises alone, reducing the use of petroleum diesel fuel by using biodiesel by 30% will give an annual economic effect of more than 10 billion rubles.

As for wood waste, then, with the exception of those used in hydrolysis plants, it is better to direct them to the production of solid biofuel. It is not without reason that one of the publications in the influential journal Science indicates that the direct combustion of cellulose-containing plants to generate electricity to charge the batteries of electric vehicles will provide these cars with more than 80% greater mileage than using liquid biofuels obtained from processing these plants.

Sergey PEREDERIY,
Dusseldorf, Germany,
[email protected]

Algae - the fuel of the future

There is enough oil for our lifetime. There may still be some oil, gas, and other fuels of organic origin left for our children. Looking into the longer term for exploration and production of mineral fuels is a futile and thankless task, but increasingly, analysts estimate the likelihood of availability of sufficient oil and gas resources for more than 50 years as slim chances.

ETBE, Ethyl tert-butyl ether, biofuel, alternative energy, liquid biofuel

However, humanity, unfortunately or fortunately, turned out to be more flexible than the society of the planet Plyuk. Until then, in addition to the color differentiation of pants, matches and mineral resources, there is money in the world, he comes up with something. I would, of course, hope that the development and implementation alternative ways energy production occurs due to moral considerations about the future of the planet, or, say, due to a possible global cataclysm with potential warming/cooling of the climate. However, in my opinion, everything is much more prosaic - people are “moving” in search of other sources of fuel only because it is becoming profitable.

What, a little gloomy and too pessimistic? For mercy, journalists are people too and sometimes they lose faith in the bright beginning of humanity. The late R. A. Heinlein spoke well on this topic in one of his best books, “Time Enough for Love, or the Life of Lazarus Long”:

Never appeal to the best qualities person. Perhaps he doesn't have them. It is safer to appeal to his personal interest.

And what, quite a vital observation, especially in light of the current state of affairs with rapid the “draining” of the world’s reserves of organic energy resources, the disastrous state of the environment in general, and the “lack of haste” in ratifying the Kyoto Protocol by a number of developed countries in particular. And for the time being, no amount of persuasion from environmentalists or admonitions from Greenpeace had much effect.

But the time has come - the price of oil has come close to $100 per barrel. There is no doubt that this magical price level has enormous psychological potential, but its value lies in an equally important economic component: when the price of mineral energy raw materials reaches $100, unclaimed opportunities open up for the production of alternative fuels, which were previously simply unprofitable due to their high cost. The increase in oil prices more than doubling over the past three years should have, one way or another, made a number of projects that had previously been shelved until better times, profitable.

So, in fact, we’ve almost reached the topic of today’s story. I would hardly be mistaken if I say that the majority of the world’s population is interested in oil prices only in the connection that it has with the prices of fuel for transport - the cost of gasoline and diesel fuel at gas stations interests us every day and much more than any macroeconomic indicators. Therefore, today we will talk about new developments in the field of production alternative fuel mainly for cars. More precisely, not about everyone possible types fuel - we will definitely talk about it in one of our future publications. But only about one of the varieties of biofuel, which is currently produced in an exotic, but very promising way.

From stools? From sawdust? From seaweed!

Oil is not the only raw material for producing high-octane organics for engine our car. In one of our previous publications on global climate change, we have already analyzed various ways to obtain alternative energy in more detail. Of course, you can’t put a windmill on a car, just like a nuclear or thermonuclear reactor; batteries to work as a source of energy for the engine car, significantly improved recently in terms of capacity, still do not yet provide an ideal solution.

Since nature, storing fossil types of organic matter for the future, did not provide for the large number of the human race and its greed, humanity will have to turn its gaze to the organic matter growing around and independently come up with ways to create fuel from improvised and, if possible, renewable sources.

A logical solution for the near future is to search among alternative methods for the synthesis of high-octane organics, without the use of depleting fossil resources. There are many such methods, one of the most popular due to the relatively low cost of production is the production of alcohol using renewable natural resources, that is, from biomass from the garden. The alcohol obtained in this way can be poured into the tank in its pure form, or it can be mixed with petroleum distillation products for additional savings. Everything would be fine, but places with suitable climate, where you can grow corn and wheat for distillation into alcohol fuel with sufficient profitability, a limited amount.

Plus, it’s purely humanly pity for grain, from which you can make bread, whiskey or beer, or whatever - even just feed it to cattle for no less interesting dividends in the form of milk and meat. Even though we have learned how to extract alcohol from the stalks of the same notorious corn or, for example, cellulose, so far without special prospects with profitability, since on average, by spending 1 megajoule of energy, you can get 1.19 MJ of gasoline, 0.77 MJ of corn alcohol and only 0.10 MJ of cellulose alcohol. There are other methods, including recycling oil already used to make crispy potatoes, we will talk about them in other publications, but many of them, alas, are also still teetering on the brink of profitability.

In search of more “interesting” organic matter for processing, scientists turned their attention to an almost inexhaustible and easily renewable resource - algae. Separately, it is worth noting that the biofuel potential of algae has been the object of close attention of scientists in France, Germany, Japan and the USA since the 50s of the last century, while the issue became especially acute during the previous oil crisis of the 70s - in complete analogy with the current state of affairs .

From time to time, such programs were revived and even then closed (oil sometimes becomes cheaper), such as the Aquatic Species Program (ASP), conducted from 1978 to 1996 by the US National Renewable Energy Laboratory - NREL (US National Renewable Energy Laboratory), with funding from the Office of Fuels Development, a division of the U.S. Department of Energy.

In fact, algae is the same organic matter, perfect for obtaining biodiesel fuel, perhaps, provides an excellent yield of biomass per square meter of cultivated area - in contrast to “land” plants; does not contain sulfur and other toxic substances- unlike oil; finally, it is perfectly decomposed by microorganisms and, most importantly, provides high percent yield of ready-to-use fuel: for some types of algae - up to 50% of the original mass!

First, let's be more precise about the subject of the conversation. Algae (Algae) in a broad sense refers to a wide variety of unicellular and multicellular organisms of the most bizarre shapes and sizes (from fractions of a micron to 40 m). Wikipedia defines the term this way: Algae (lat. Algae) are a group of autotrophic, usually aquatic, organisms; contain chlorophyll and other pigments and produce organic matter during the process of photosynthesis. We are mostly interested in microalgae.

Typically, microalgae live wherever there is moisture, but the most extensive “suppliers” of algae in natural environment are swamps and lakes, including salty ones. In complete analogy with plants, algae require three main components to grow - sunlight, carbon dioxide and, of course, water. In the process of photosynthesis - a key bioprocess for plants, algae and a number of bacteria, the energy of the sun is processed into " chemical energy"In addition, microalgae manage to accumulate various lipids and fatty acid, while their content fluctuates different types algae ranging from 2% to 40% of total weight. It is precisely these components that, in fact, interest scientists in the first place.

Is the game worth the candle? Maybe it’s okay to get confused in this dirty mud for the sake of dubious pleasure? It's worth it, it's worth it! The data I found on the Permaculture Activist website is, frankly, stunning.

May meticulous readers forgive me for being too lazy to convert gallons to liters (one American gallon is approximately 3.785 liters). The point, as you understand, is not so much about absolute numbers; perhaps it is much more important to pay attention to the tens of times higher indicators of microalgae relative to traditional “land” crops.

As an example of serious research on algae cultivation, one can cite the results obtained by the above-mentioned NREL laboratory during the oil crisis of the 70s as part of the Aquatic Species Program (ASP). To produce biodiesel rich in lipids, installed outdoors transparent “cages” into which CO 2 gas was supplied from a nearby coal-fired power plant. As a result of experiments, ASP was able to identify about 300 subspecies of algae - mainly diatoms (siliceous) algae (Diatoms) and green algae (Chlorophyceae), allowing to achieve the following results:

• Under optimal microalgae growth conditions, achieve production rates of up to 15,000 gallons per acre per year
• 7.5 billion gallons of biodiesel could be produced from 500,000 desert acres (producing the same amount of biofuel from canola would require about 58 million acres).
• Algae contain fats, carbohydrates and protein, in some cases up to 60% fat, up to 70% of which can be “extracted” by simple squeezing.
• It was not possible to find suitable crops for cultivation outside the cages.

The program, which was curtailed ten years ago due to low profitability due to lower oil prices, has recently received a “second wind”, since, in connection with the assault on oil prices at the $100 mark, in October the US Department of Energy, in collaboration with Chevron, announced about the search for new technologies for processing algae. In addition, the Pentagon's DARPA is currently sponsoring the development of plant-based aviation fuels, including algae, and is currently working closely with UOP (Honeywell), General Electric, and the university. North Dakota. Funding is said to have increased further since November.

So, should we give up oil production and start farming swamps? It’s a joke, of course, for the production of biodiesel fuel, special “cages” - bioreactors for growing algae - are more often used. Alas, there is plenty of skepticism, and mainly the question lies in two difficulties - the stability of daily weight gain and the possibility of bringing the technology for processing algal raw materials into biofuel to a commercially acceptable level. Thus, in one of the articles on the Biopact website, pessimism regarding “algae” factories is meticulously justified.

On the other hand, just imagine what a vast field of action there is for those who like to modify genes - it would be better to put their efforts here than to clone sausage (I hope that today my opinion on genetically modified food is not very striking. It is sharply negative, but about that next time).

Well, as they say, the only thing left to do is to learn how to properly process all this wet biomass into a consistency suitable for pouring into a car tank.

There are currently three widely used methods for processing algae into fuel, and all three are borrowed from oilseed processing methods - using a press or oil separator; this is selective extraction in a supercritical state (Supercritical Fluid Extraction); This is selective separation and purification using hexane (Hexane Solvent Oil Extraction).

It should be noted that in the United States, dozens of companies and many scientific groups at various universities in the country are working on the problem of obtaining inexpensive biodiesel fuel for cars. It’s embarrassing to say, but I didn’t even realize the scale of work on this topic in the United States until I started studying the issue. Unfortunately, I was never able to find any statistics on the volume of fuel production from algae, but there is simply an abyss of links to the websites of companies, laboratories and various foundations seriously dealing with this issue.

Today I will tell you only about the latest and most interesting recent report on the topic of creating inexpensive and effective biofuel from algae, which, in fact, became the reason for this publication. We are talking about the developments of the Center for Biorefining Technologies at the University of Minnesota. A group of scientists at this center have been exploring the possibilities of using different types of algae to produce inexpensive biofuels for cars for many years.

In the photo above, you can clearly see the greenish tint of the “raw materials” developed in the laboratory of Roger Ruan. The main achievement obtained by Roger Ruan and his colleagues is the full-cycle technology for producing biofuel from algae, including methods for increasing the rate of mass growth, effective “squeezing” techniques, as well as effective ways to dispose of waste remaining after biomass processing.

The main problem restraining the rapid growth of algae mass is considered to be too small - only a few centimeters - the possibility of sunlight penetrating into the thickness of the water-plant mixture, which is why the efficiency of using large containers, and open reservoirs in general, turns out to be very low. In this regard, scientists from Minnesota managed to develop a principle of operation of a “photobioreactor” that ensures optimal mode mixing light and nutrients for good yield when working even with “wild” algae cultures.

Perhaps, while reading this material, someone has already formed an analogy of a “photobioreactor” with a trivial round artificial reservoir - a typical wastewater treatment facility. It is at the wastewater treatment plant that Ruan and a team of colleagues are experimenting with growing algae. Fortunately, wastewater filtrates contain plenty of phosphates and nitrates - substances that extremely pollute rivers, but are very useful and nutritious for algae. The Minnesota scientists' vision of the future includes "algae farms" next to wastewater treatment plants that consume everything they need from wastewater - including carbon dioxide produced by burning sewage sludge.

The main goal facing researchers today is to reduce the cost of biofuel production. According to representatives of UOP LLC, a division of Honeywell International for the development of biofuels, the result can be considered satisfactory if the level is achieved below $2 per gallon, and, which is significant, now many experts do not see anything unrealistic in this. However, the Pentagon is quite agreeable if aviation fuel made from algae costs less than $5 per gallon, and ideally less than $3 per gallon.

If you fantasize to your heart’s content, you can imagine “algae factories” anywhere, fortunately, that’s all, and humanity has learned to produce waste best in unlimited quantities. Moreover, such a factory will not require the use of arable land at all - as is the case with the production of biofuel from plants, and there will no longer be an increase in the price of vegetable oil and bread due to the waste of crops on fuel production.

The most interesting thing, perhaps, is that there are a large number of algae in the world that happily live and reproduce in salty sea water. This state of affairs, combined with the “omnivorousness” of bacteria in relation to waste from treatment plants and thermal power plants, can be called the quintessence of a reasonable approach to combating planet pollution and the rose-colored dream of all ecologists.

Instead of an epilogue

Last year, a New Zealand company showed the world a Range Rover modified to run on algae-derived biodiesel. Then experts were very skeptical about the prospects of such cars and unanimously stated that many years would pass before this technology would become relevant. Yeah, it’s good to be smart when the oil price is $50-$60 per barrel, it would be interesting to listen to these experts adjusted to current prices.

But a group of scientists from Minnesota is full of optimism and promises to present to the public several “demonstration” factories for processing algae into fuel in the next few years.

Being somewhere in the middle of writing this material, I planned, towards the end of the article, to “spread poison” at the land reclamation workers who recklessly drained many swamps in their time. After all, in addition to the deathly distorted ecology of such regions, now, you see, the swamps would be good for something. Okay, today’s story will do without land reclamation agents. See you next time, and write what topics of IT stories would be interesting to you in the future.

http://www.3dnews.ru/

ETBE, Ethyl tert-butyl ether, biofuel, alternative energy, liquid biofuel

Biofuels are becoming increasingly popular among consumers and producers. Moreover, if it is expensive to produce, like any other type of business, then selling it to consumers is not difficult. The main motive used by sellers is respect for nature, lack of harmful effects, and besides - high efficiency and low cost compared to traditional fuel. The main types of biofuels: biodiesel, biogas, and the most popular – bioethanol.

International control

An interesting fact is that the European Commission intends to encourage member countries to switch cars to biofuels in the amount of 10% of their vehicles. total number. To achieve this goal, European countries have created and operate special tips and commissions that encourage car owners to re-equip their engines, and also control the quality of biofuel supplied to the markets.

To maintain the biobalance on planet Earth, commissions ensure that the number of plants that serve as raw materials for food production increases and is not replaced by plants from which biofuel is produced. In addition, enterprises that produce biological fuels must constantly improve their technologies and focus on the production of second-generation fuels.

Fuel realities in Russia and in the world

The results of such active work were not long in coming. For example, at the beginning of the second decade of the century, 300 gas stations were already operating in Sweden, where environmentally friendly biodiesel can be filled into the tank. It is made from the oil of famous pine trees growing in Sweden.

And in the spring of 2013, an event occurred that became a turning point in the development of aviation fuel production technologies. A transatlantic plane filled with biofuel took off from Amsterdam. This Boeing landed safely in New York, thereby marking the beginning of the use of environmentally friendly and inexpensive fuel.

Russia in this process takes a very interesting position. We are producers of various types of biofuels, occupying third place in the ranking of exporters fuel pellets! But within our own country, we consume less than 20% of fuel, continuing to use expensive types.

27 regions of Russia became experimental sites where power plants operating on biogas were built and launched. This project cost almost 76 billion rubles, but the savings from the operation of the stations exceed these costs many times over.

Second generation biofuel

The difficulty of production is that it requires quite a lot of plant raw materials. And to grow it, you need land, which, in the right situation, should be used to grow food plants. Therefore, new technologies are aimed at producing biofuel not from the whole plant, but from waste from other production. Chips from woodworking, straw after threshing grain, husks from sunflowers, cake from oilseeds and fruits, and even manure and much more - this is what becomes the raw material for second-generation biofuel.

A striking example of second-generation biofuel is “sewage” gas, that is, biogas consisting of carbon dioxide and methane. In order for biogas to be used in cars, carbon dioxide is removed from it, leaving pure biomethane. Bioethanol and biodiesel are obtained from biological mass in approximately the same way.

Sunflower, soybean or rapeseed are the main plant species from which biodiesel is produced. It is not used in its pure form in cars. It is mixed with traditional diesel fuel, and biodiesel should be contained in a ratio of 1:4, that is, one fifth of biodiesel and four-fifths of regular diesel. That is why the use of biodiesel fuel is very simple in technical terms. The car engine does not require changes or modifications. Exhaust gases when using biodiesel are much cleaner in environmental terms, content harmful substances much lower than acceptable environmental parameters. The energy efficiency of biodiesel is slightly lower than that of pure diesel, therefore the power of a car engine is reduced. Consequently, slightly more fuel is required.

The production of biodiesel allows the use of any types of oils from plants - sunflower, rapeseed, flax and others. Different oils give biodiesel their own characteristics. Palm biodiesel has a high caloric content, it solidifies and is filtered at high temperatures. Biodiesel from rapeseed responds well to cold, so it should only be used in northern areas.

How is biodiesel made?

To produce biodiesel, the viscosity of vegetable oil must be reduced. To do this, glycerin is removed from it, and alcohol is added to the oil instead. This process requires several filtrations to remove water and various impurities. To speed up the process, a catalyst is added to the oil. Alcohol is also added to the mixture. To obtain methyl ester, methanol is added to the oil, and ethanol is added to obtain ethyl ester. Acid is used as a catalyst.
All components are mixed, then it takes time to separate. The top layer of the container is biodiesel. The middle layer is soap. The bottom layer is glycerin. All layers go into further production. Both glycerin and soap are compositions necessary in the national economy. Biodiesel undergoes several purifications, dried, and filtered.
The figures for this production are quite interesting: a ton of oil, when interacting with 110 kg of alcohol and 12 kilograms of catalyst, results in 1,100 liters of biodiesel and more than 150 kg of glycerin. Biodiesel has an amber-yellow color, like beautiful freshly pressed sunflower oil, glycerin is dark, and it hardens already at 38 degrees. Good quality biodiesel should not contain any impurities, particles, or suspensions. For continuous quality control when using biodiesel, it is necessary to check automobile fuel filters.

Bioethanol

This type of biofuel is produced from plant raw materials - from sugar cane or corn. The main producers of this type of biofuel are the USA and Brazil. Bioethanol is added to regular gasoline. Moreover, the name of gasoline includes the percentage of biofuel in the mixture. For example, E-10 contains 90% gasoline and 10% biological ethanol. This type of gasoline is suitable for any car engine. But the E-85 mixture, which contains 85% biofuel, requires technical modification of the car engine.

Bioethanol production

Fermentation of raw materials rich in sugars is the basis for the production of bioethanol. This process is similar to producing alcohol or regular moonshine. The starch of the grain is converted into sugar, yeast is added to it, and the result is mash. Pure ethanol is obtained by separating fermentation products, this occurs in special columns. After several filtrations, drying is carried out, that is, water is removed.

Bioethanol without water impurities can be added to regular gasoline. The environmental purity of bioethanol and its minimal impact on environment is highly valued in industry; in addition, the price of the resulting biofuel is very reasonable.

Third generation biofuels

The third generation of biofuel is algae fuel. The value of such technology is enormous. There is a huge amount of land on the planet that is not suitable for growing food plants. It is on it that algae take root well. You just need to create small artificial ponds or special closed bioreactors. Founded this technology on the fact that oils accumulate in algae during growth. And scientists have discovered that the molecules of these oils have a similar structure to regular oil.

All that is needed for algae to grow is water, light, carbon dioxide, and a nutrient medium. Moreover, the process of algae growth has another positive effect for humanity: during growth, they consume carbon dioxide, ridding the planet of the greenhouse effect, and saturate the atmosphere with oxygen. When processed, algae produces 3.5 times more fuel than palm oil, 5 times more than sugar cane, 8 times more than corn, and 40 times more than soybeans.

E. Shchugoreva

Algae are one of the fastest growing plants on Earth. Their weight doubles per day, and growth requires resources that are abundant on Earth: sunlight, water and carbon dioxide. According to their own energetic properties algae is superior to many other sources for biofuel production. The growth of algae is a controlled and unpretentious process for humans. Moreover, algae absorb carbon dioxide from the atmosphere through biosynthesis.

The main problem that currently hinders the development of industrial production of algae is that algae are very sensitive to changes in water temperature, which, as a result, must be maintained within a strictly defined range (sharp daily fluctuations are not acceptable). Also, the industrial production of algae is hampered by the lack of effective ways collecting algae. The difficulties described above led scientists to the conclusion that it is advisable to grow algae only in closed and technologically convenient reservoirs. The US Department of Energy has studied algae with high oil content. The researchers concluded that California, Hawaii and New Mexico are suitable for industrial algae production in open ponds. For 6 years, algae were grown in ponds with an area of ​​1000 square meters. meters. The yield was more than 50 grams of algae from 1 square meter in a day. In addition to growing algae in open ponds, there are technologies for growing algae in small bioreactors located near power plants. Waste heat from a thermal power plant can cover up to 77% of the heat required for growing algae. This technology does not require a hot desert climate.

Currently, mass production of microalgae suitable for immediate use has been established in special bioreactors in which algae reproduce by fission.

Chevron Corporation, one of the world's energy giants, has begun research into the possibility of using algae as a source of energy for transport, in particular for jet aircraft. Honeywell, UOP recently began a project to produce military jet fuel from algae and vegetable oils. Green Star Products has completed Phase 2 testing of its algae biodiesel demonstration plant. During the second phase, optimal conditions for growing algae were selected. Large energy company Japan's Tokyo Gas Co intends to build a demonstration plant where electricity will be produced from seaweed. For work gas generators The station will use methane released from finely chopped algae. Coastal algae pollution remains serious for a number of Japanese prefectures environmental problem. When they rot, they often emit a foul odor and spoil the landscape. Meanwhile, the latest development of Japanese specialists offers to solve this problem with economic benefits. An experimental model of a plant with a gas electric generator, which has already been operating in the laboratory for several years, allows processing up to 1 ton of algae per day. This generates about 9.8 kilowatts of electricity. This pilot plant produces about 20–30 cubic meters of methane per month—enough to cut the average family's monthly electricity consumption by exactly half.

The aviation industry has also announced the beginning of developments in the use of seaweed as a raw material for the production of aviation fuel. Boeing has announced that an alternative to biodiesel made from seaweed could be used in the future for the production of aviation biofuel. According to the document, no biofuel produced today can be used as aviation fuel. Ethanol absorbs water and corrodes the engine and fuel line, while biodiesel freezes at low temperatures(at cruising altitude). In addition, biofuel has lower thermal stability than conventional jet fuel. Boeing experts believe that the optimal raw material for biofuel production will be seaweed, which produces almost 300 times more oil than soybeans. According to Boeing, algae biofuel is the future for aviation. So, if the entire world airline fleet used 100% biofuel derived from seaweed as of 2004, 322 billion liters of oil would be needed. To grow these algae, land with an area of ​​3.4 million hectares is required. The calculation assumes that one hectare yields 6,500 liters annually. For these purposes, it is possible to use lands that are not suitable for growing food crops.