George G. Belitsky Alcohol as Car Fuel

Transcription

1 George G. Belitsky Alcohol as Car Fuel Halting the use of oil products for fuel and exchanging it for the use of several other alternatives is a move which could greatly benefit the ecology and yield substantial monetary benefits. One particularly good alternative to oil is alcohol, and primarily ethanol. When using alcohol for fuel, the ecological balance is maintained perfectly: its chemical energy is obtained from the sun through photosynthesis, and when it is burned, all of the materials it had used for growth are returned to the environment. Therefore, for example, carbon dioxide balance in the atmosphere does not change. Also, the emissions created by burning alcohol are substantially less toxic than those created by burning oil products. Brazil has shown the most success in using alcohol as fuel, as about half of the cars in that country use alcohol instead of gasoline for fuel. While in Brazil, I had been familiarized with the use of alcohol produced from sugar cane, visited the farm-factory, was at the gas column, talked to car owners and professionals for conversion of vehicles. Here are my and my son Vladimir's photos and impressions regarding this trip and some of my reflections. Sugar cane in this country grows almost without care and it grows tall, thick and juicy.. At the end of the season, 2-3 temporary workers collect the cane via a combine and serve it into a toothed roller that kneads the stems. 1

2 Then they lay the cane into one of the pits, lined with waterproof cloth, add yeast, moisturize and tamp, then tightly cover it by the same cloth. After a while, liquid containing alcohol flows by gravity from the well through a hole in the bottom of it and a pipe into a distillation unit, located under the slope. Here we see another working feeding sugar cane from an older hole (one in which the sugar cane has already dried) into the oven located under the distillation vat. He uses only part of the sugar cane, and the rest is used to feed livestock. 2

3 Alcohol evaporates from the mash, passes through the water cooled tube (refrigerator) and enters the container. An abundance of the alcohol can be seen in the picture. The owner of the farm-factory carries out financial and administrative functions and all other service functions. One among his functions is to direct a small part of the alcohol to an additional distillery machine. After the second distillation, exposure and necessary additions, a rum-like drink appropriate for personal consumption is created. 3

4 Industrial alcohol from this factory is too watered down to be useful as car fuel. Gas stations in Brazil provide alcohol with a water content of no more than 7 percent. Therefore, products manufactured here are sent to a chemical plant where the alcohol is adjusted to the desired concentration in distillation columns. Then some necessary additives are dissolved in it, after which it is sold to car owners. The gas stations in Brazil also hold petrol taps, but none of those provide pure gasoline. It is always mixed with alcohol in quantities reaching up to 23 percent. The price of alcohol is less than the price of gasoline. Concurrently, the ratio of prices of alcoholbased fuel and gasoline in Brazil are about such: K 1 = 1.96 (real / L) / 2.79 (real / L) = 0.7 However, the calorie concentration in alcohol falls behind that in gasoline. Therefore, it is necessary to spend a greater proportion of alcohol to obtain the same amount of energy, the ratio being: K 2 = 43 (MJ / kg) / 30 (MJ / kg) = 1.43 The product of these ratios comes close to 1 K 1 K 2 = 0.7 * This means that the plain consumer does not benefit economically from this arrangement. However, pollution is substantially less prevalent, and the state turns a substantial profit by producing its fuel locally and being independent of oil tycoons. Since the octane number of alcohol is higher than that of gasoline, proper adjustments and intelligent manufacture of alcohol-consuming engines allow for an efficiency that is 10 to 30 percent higher than the one achieved with gasoline. This allows a wise consumer to reduce the cost of fuel for his car. For conventional carbureted cars to drive on alcohol, it is necessary to make some small adjustments: widen the holes in the carburetor jet to increase the supply of fuel to maintain the nominal power of the engine; insert a buffer between the block and cylinder heads of a different thickness to obtain a greater degree of compression; replace the conventional gas tank for a stainless steel tank to avoid rusting, and set a small tank of gasoline in the engine compartment (visible in the photo, with a red cover ), which supplies the carburetor only when the engine ignites. 4

5 The use of gasoline with a small addition of alcohol does not require any alterations to conventional cars. Cars that work efficiently with either fuel type (alcohol or gasoline), or any mixture of the two, without any adjustments, are manufactured and sold in Brazil. Let us compare the energy output of sugar cane with semiconductor converters of solar radiation. In Brazil, a hectare of field provides M = 60 tons of sugarcane, and about m = 42 liters of ethanol per a ton of these plants is produced on average. Considering the calorific value of alcohol: q=30mj/kg with its relative density of d=0.76 kg / L, and that there are usually 2 crops obtained per year, it is possible to calculate the amount of energy obtained by combustion of alcohol per square meter of field covered with sugar cane: E 1 = (2Mmqd) = (2x60 ton/hectare year 42 L/ton 0.76 kg/l 30 MJ/kg)/10,000 m 2 /hectare = 11 MJ/m 2 year. Almost all of the alcohol derived from sugar cane in Brazil is used as motor fuel, but suppose that we decided to use it for the production of electricity. With the use of a thermal power plant (the efficiency of which is usually about η = 35%), we would obtain, from one square meter of a field covered with sugar cane: E 2 = E 1 η = 11 MJ/m 2 year 35% KWh / MJ = 1.08 KWh/m 2 year A solar power plant in the Negev, placed in the optimal location for such purposes, receives E3 = 2400 KWh of solar radiation per year, per square meter (a number that is substantially lower in Brazil s climate). Conversion of this energy into electricity is done with an efficiency of η 1 = 16% with the best equipment available, resulting in a gain of: E 4 = E 3 η 1 = 2400 KWh/m 2 year 16% = 380 KWh/m 2 year This is significantly more than that of sugar cane in Brazil, using the same amount of area. However, there is significantly more area fit for farming than there is fit for laying down solar power plants. Thus, in 2011, Brazil's sugar cane occupied about S 1 = 10 million hectares (100,000 square kilometers). To obtain the same amount of electricity as can be obtained from these plants, it is necessary to occupy the following area with photo-transformers: S 2 = S 1 E 2 /E 4 = km KWh/m 2 year/380 KWh/m 2 year = 280 km 2 It is incredibly expensive and technically unfeasible. 5

6 Brazil is the world's largest producer of ethanol, as it produces 20 percent of the world s ethanol. Creating jobs in rural areas is one of the most important positive results of Brazil's "ProAlcool" program. The country has created more than 700 thousand jobs directly related to the production of sugar cane and three to four times more jobs indirectly related to it, resulting in about 4 million jobs. Note that the artisanal alcohol production shown here is not very efficient - it allows one to convert about 4 percent of the collected sugarcane into alcohol. Modern fermentation and distillation apparatus can produce 2-3 times more alcohol, but they are more expensive and require skilled care. In Brazil, there is ample space for all the necessary sugar cane, while still leaving an excess for other agricultural pursuits and for forests. Skilled labor and advanced equipment, on the other hand, is beyond the reach of most Brazilian farmers. Alcohol can be produced from all manner of plants other than sugarcane, some of them containing almost no sugar. It is known that in Israel there was a company was developing the production of ethanol from algae. It was assumed that small lakes of sea water or brackish water would be created in the Negev desert and populated with algae for this purpose. The algae were to be periodically raked and large amounts of cheap industrials alcohol was to be created from them. There is no lack of vacant land in the desert in Israel, nor is there a lack of salt water or sun. Using genetically modified bacteria which decompose and convert cellulose and/or other compounds, it is possible to convert up to 28 percent of the dry weight of the material into alcohol 7 times more than what is possible with sugarcane. Furthermore, the yield of algae is 5 to 8 times higher. However, the company had disappeared from Israel, and has seemingly moved to California, denying Israel a good deal. Details: 1. Ethanol as liquid fuel Gregory Kolpakov. Alcohol instead of oil from algae Vladimir Romanchenko. Algae - fuel of the future? 4. Leonid Popov. Genetics forced the bacteria to produce alcohol from microalgae Wikipedia. Biofuels. ; 6. Greenbang. Corn ethanol curse strikes again Trachtenberg R.M. Solar energy enables to live in the world without oil and nuclear power plants Gershon Belitsky. Why a car on aluminum isn t necessary. 6