As the name implies, bioethanol fuel refers to ethanol or alcohol made from natural materials, usually plant by-products. Bioethanol can be produced chemically by reacting ethylene with steam. However, it is mainly produced by the fermentation of sugar and the main source of the sugar used in the production of ethanol comes from fuel or energy crops. These energy crops are usually grown specifically for the purpose of energy use and are normally high in starch. They include crops such as maize, millet, corn, and wheat crops. It can also be produced from materials such as straw, sawdust, willow, and grasses like reed canary grass, cord grass, and many other plants. There is also ongoing research on the production of ethanol from solid waste materials. Let us consider the process of processing these raw materials into bioethanol, which can be used for ethanol fireplaces.
How is bioethanol produced?
The entire process of manufacturing bioethanol can be divided into 3 major steps. These steps are
- Distillation and,
- Dehydration and denaturing (optional)
For some crops, however, before fermentation can begin, they require scarification or hydrolysis of the carbohydrates present such as cellulose and starch into sugars. Enzymes are usually employed to carry out this process.
- Fermentation: Employing enzymes or microbes, the sugar is fermented. Currently, this fermentation will only work directly on sugars. Plants contain two major components; starch and cellulose, both of which can be converted to sugars for fermentation. As of the moment, however, only the sugar portions such as is present in sugar cane, and starch portions such as in corn ,can be converted economically.
- Distillation: After fermentation, there are still large amounts of water and other impurities in the mixture and this can hardly be made use of as fuel. The mixture needs to be distilled to get rid of most of the water. The mixture is heated to a temperature where only ethanol evaporates and is then cooled back down to a liquid state. However, the purity of the ethanol produced is still limited to 95-97% at this level. The ethanol can, however, be purified more by dehydrating it further which brings us to the next stage
- Dehydration and denaturing: The impurity; which at this point refers to a water-ethanol azeotrope is removed by a physical absorption process using a molecular sieve. Another method involves azeotropic distillation by adding benzene which also denatures the ethanol. A third method dries the ethanol by using calcium oxide as a desiccant.
Can you produce bioethanol at home?
Yes. Many people produce bioethanol for their own use in their homes. Many people employ the use of a homemade still for the production of ethanol, however, the quality of the alcohol produced poses a problem for most inexperienced producers.
Advantages of biofuels.
Some of the reasons why biofuels such as ethanol are gaining attention are stated below:
- Price. The price of this biofuel will remain low due to government subsidies and low taxation rates. This is proving to encourage the use of bioethanol as a fuel not only for ethanol fireplaces but for many other functions.
- The environment. High-quality bioethanol, upon combustion only produces carbon dioxide and water as the waste products. The amount of carbon dioxide released equals that which was removed from the atmosphere while the crop is growing. Also, as ethanol is largely produced from by-products of energy crop production, it negates the need to cut down trees for use as firewood.
Why is bioethanol preferred over wood for fireplaces?
Even as many people enjoy the familiar look, feel and even smell of a conventional wood fire, this option of a fireplace poses some major problems. One of these problems is the issue of the chimney. Wood fires require a chimney for ventilation purposes but as a result of this design, they lose heat through the chimney and as such, they aren't completely efficient. Also, high-quality wood for fireplaces can be quite expensive depending on where you obtain it from. Also, due to the high carbon content of wood, during combustion, the number of particles released can be very detrimental to your health whether in the long run or sometimes even immediately.
The advantages of ethanol fireplaces or ethanol fireplaces inserts over wood fires and the reasons people choose ethanol fireplace inserts instead of wood fireplaces include the fact that it is far more eco-friendly and efficient. Ethanol fires produce no smoke and polluting particles and as a result, do not require chimneys to evacuate the air. And as these ethanol fireplaces require no chimneys, 100% of the heat produced from heating the bioethanol stays in the room. This produces a more even distribution of the heat and this will result in a much more efficient heating design.
Precautions to be taken while making use of bioethanol in ethanol fireplaces.
As this fuel is in a liquid state and easily evaporates, it makes for a very flammable fuel. Unlike wood which takes time to burn, in the presence of ample oxygen, bioethanol ignites almost instantly. As a result, care must be taken when making use of it as fuel.
- Store bioethanol fuel in a closed container, away from all sources of heat and out of the reach of children.
- Use only high-quality fuel specially made for the purpose of lighting ethanol fireplaces.
- Clean up any spills and allow time for the spills to evaporate before lighting the fireplace.
- Never attempt to refill a fireplace that is still lit or isn't completely cooled as this can result in a fire or can cause injury
- Allow at least 15 minutes for the fireplace to cool completely before
There is no doubt that the ethanol fireplaces are gaining popularity among a lot of people today. This has been made possible through the bioethanol. When used properly and in line with all the precautionary measures, the results have the ability to make your ethanol fireplace inserts run smoothly. Therefore, it is imperative that you know how and when bioethanol should be used in order to ensure your safety