Biomass is referred to the material made from the living organisms that have died and are in the process of decaying. In most cases biomass used by human beings comes from remains of plants and other plant-derived materials. Biomass is of a great interest to the humans, since it can be used in order to provide energy. This type of energy is renewable, meaning it has an ability to avoid depletion with good management. The fuel that is derived from the decayed plants and plant-derived materials is referred to as biofuel. Biofuel can be harnessed from the plant materials in the three major ways; these are: through biochemical conversion, through chemical conversion, and through thermal conversion. Details about these three processes are contained in this essay. This essay also aims at analyzing the importance of embracing biomass as a source of fuel to promote environmental conservation.
Humans are in dire need of energy reserves that are renewable, since extinction is realistically far from sight. Most of the energy forms that humans have been using are non-renewable. This is a big economic challenge. Continued depletion of the sources of fuel greatly relied on by the human begins is likely to stall economic development. Fuel is a subject of the law of demand, which states that an increase in demand causes an increase in the prices for acquisition of the commodity. On the other hand, when the demand is low, the prices go down. However, demand for a product is dictated by the supply, especially if the commodity is an essential one. Fuel is one of them. Depletion of sources of fuel means that the supply will be low with time, therefore, the prices will increase.
Biomass is one of the most suitable alternatives to evade the dangers of depletion of over-relied fuels, such as oil and nuclear deposits. Biomass can be used in order to generate electricity by using gasifies or steam turbines, as well as combustion of the plant materials. Wood is one of the major sources of biomass. One might argue that wood is non-renewable fuel, but continued planting of trees, as they are cut down, ensures that wood does not get depleted. Some industrial activities use plants and animals materials to derive biofuel. Some of the often used materials include switch grass, hemp remains, corn stalks and leaves after harvesting, poplar, willow branches and leaves, miscanthus sorghum stems and leaves after harvesting, sugarcane residues, palm oil trees residues, bamboo stems and leaves, as well as tree species like eucalyptus.
Though people have taken a slow toll in embracing this type of energy, there is a steady growth in the usage of biofuel all over the world. Well done case studies have been conducted in the American countries, especially in the US, where this subject is proven. Though the country greatly relies on nuclear and petroleum for fuel, 14% of the energy used in the country is alternative. Of the 14%, 11% comes from biofuel.
As stated above there is a variety of resources used to derive biofuel. Research has estimated a total of 146 billion tons of biomass produced yearly throughout the world. The major contributor of this tonnage is decayed wild plants materials. There are six principal sources, which biomass is derived from; they include: garbage, landfill gases, alcohol fuels, plants, wastes, and wood.
Wood is one of the most important sources of biomass. It is derived using the second generation biofuel techniques, basically referred to as lignocellulose biomass. This is done by either direct combustion of wood and wood products or by collecting wood wastes from streams and using them to make biofuel. The paper, pulp, and paperboard industries have discovered the largest source of biofuels from wood. These plants produce pulping liquor or so-called black liquor, which is used to generate energy.
The second largest source of biofuel is waste energy. This energy is derived from the day to day waste products, such as municipal solid wastes from garbage and sewage, manufacturing waste products, and landfill gases.
The first generation biofuels, which include sugars and oils, such as corn and sugarcane, are also used to produce biomass energy. In this perspective, bioethanol, an alcohol fuel, is derived from these materials. Studies have shown that people prefer the above second generation biofuels to the first generation ones, since the former are comparatively simple to extract and use, because they are directly used in most cases; they can also be processes, and the procedure is quite simple. However, first generation biofuels are accompanied with the food vs. fuel conflict, both of which are essential to the human beings.
Biomass can be converted into other forms of renewable and environmental friendly energy forms, such as methane gas, and transportable energy forms, like ethanol and biodiesel. Biodiesel is vegetable oil or animal fat-based diesel that consists of long chains of alkyl groups. Production of biodiesel involves reaction of a lipid, such as vegetable fats or animal oil, and alcohol. As a result, a fatty acid ester is formed. Biodiesel can be used either in its pure form (B100) or combined with petroleum diesel and used in machinery. Pure biodiesel produces lees carbon dioxide and other toxic gases in the atmosphere, as compared to blended biodiesel. However, blending biodiesel with petroleum diesel reduces the potential of the latter to release toxic substances to the environment that causes pollution. Biodiesel used in the vehicles has, however, been noted to breakdown rubber gaskets and hoses, even though at a slow rate. In retaliation, manufacturers of automobiles that use this type of fuel have been advised to use FKM, which is resistant to the reactive effect of biodiesel. When vehicles or other machinery change their fuel preference from petroleum diesel to biodiesel, there is a noted clogging of engine and fuel filters. This is because biodiesel is known to break down deposits of residues or petroleum fuels formerly used in the engines. As a result, it is recommended changing the fuel filters, when changing from the use of petroleum diesel to biodiesel in order to avoid engine knocks. Use of biodiesels has been approvingly embraced in the motor vehicles industry, aircrafts, and railway transport, ever since its first research and application was conducted by Rudolf Diesel’s in 1893.
Other sources of biomass fuels are constantly being explored in the world. Algal fuel has been of a great interest to the researchers, since it is independent of the food sources. On the other hand, it has a higher potential than other sources of biofuel, producing 5 to 10 times the amount of fuel derived from plants and agricultural and waste products. Algal biomass can be used to produce a range of fuels, such as ethanol, methane, butanol, hydrogen, and biodiesel. There is diversity in production of such biofuels. It can be used commercially to produce the above mentioned fuels. It can also be produced as a byproduct of nutrient removal systems like the algal turf scrubber. This is used to restore oxygen in the aquatic habitats and other waste water treatment plants. Researchers are banking on the genetic engineering and modification to identify the species of algae that are best suited for biofuel production. They are targeting the species that will produce the maximum amount of biofuel attainable from this technique with fewer risks.
Conversion of Biomass
Heat is the main technique of deriving energy in this process. However, the chemical reaction involved should be established before choosing the alternative techniques, which include pyrolysis, torrefaction, combustion, and gasification. This is mainly determined by the availability of oxygen in the process and the temperature, under which the process is taking place. Dendrothermal energy that is derived from burning biomass is most suitable in areas that experience temperate kind of climate. This is because trees are the major vital input in this energy source. Temperate regions provide the suitable conditions for the rapid growth of trees, therefore, avoiding depletion of the energy source. Researchers are spending time on other experimental techniques, such as hydrothermal upgrading or hydroprocessing. Some processes aim at deriving more useful energy from highly moist biomass, such as aqueous slurries. Some other techniques in thermal combustion involve a combination of heat, power, and co-firing (combustion of two different biomass materials at the same time). This provides a cheaper way of harnessing energy, since one existing plant can be used to burn another different plant and the fuel derivatives can be combined.
In an effort to produce biofuel that is more convenient, transportable, and storable, chemical processes are employed in biomass conversion. Some of these processes include Fischer-Tropsch synthesis, methanol production, and olefins (ethylene and propylene). In almost all these techniques the first step of derivation involves gasification. This is the most expensive step of these processes. On the other hand, it involves a lot of technical knowhow and technical risks. Since biomass is in most cases shapeless in nature, it is hard to feed in pressure vessels. As a result, combustion of biomass is done at the atmospheric pressure. The problem with this step is that the atmospheric pressure does not provide the necessary conditions for complete combustion of the materials. Therefore, the products contain a mixture of combustible gases, such as carbon monoxide, hydrogen, and trace elements of methane. This producer gas (mixture of gases) can provide fuel for various important processes, which include internal combustion engines, as well as an alternative for oil used in furnaces. This process is far much better than ethanol or biomass production, since any biomass can undergo combustion; hence, gasification. It provides an easy way of converting solid waste products into useful energy gases.
There are other chemical commodities that have successfully been produced using biomass. Halomethanes are some of them. These are produced using a combination of A. fermentants and engineered S. cerevisiae. This technique is aimed at converting materials like sugarcane, poplar, corn stover, or switch grass and sodium salts into halomethanes. S-adenosylmethionine, a compound naturally occurs in S. cerevisiae facilitates the transfer of a methyl group in the conversion process. This process is an evidence of the fact that biomass can be used to produce multiple commodity chemicals.
The fact that biomass is natural makes it a subject to decomposition by various microorganisms and other biochemical processes. Many of these processes involved in the decomposition can be harnessed and be converted to energy. There are the three processes that involve microorganisms. These are anaerobic digestion, fermentation, and composting. However, other techniques use other different biochemical processes in harnessing energy. A good example is biodiesel derived from transesterification. This is both a biological and a chemical process of converting straight and waste vegetable oils into biodiesel. Fermentation involves breaking down the carbohydrates, and simple sugars contained in waste products to provide alcohol. However, perfection of this technique is yet to be done, since it has to be set under the right temperature and pressure conditions in case if the products are commercially targeted.
Environmental and Economic Impact
It has been noted that use of biomass fuel has reduced the prevalence of environmental pollution. Combustion of these fuels produces low levels of toxic gases, such as carbon monoxide and carbon dioxide. Currently, global warming is one of the latest and greatest global concerns. The ozone layer is gradually getting depleted and, therefore, exposing people and other living organisms to the harmful radiations from the sun. This has led to an increased prevalence of diseases related to the UV rays, such as skin cancer and other catastrophes like tsunamis and hurricanes. The recent incidences have been experienced in North America (hurricane Sandy) and Japan. Also, global warming has changed the weather patterns around the globe. Sub-Saharan African drought period has increased, leading to the increased famine and food shortages. One of the main contributors to the global warming is use of energy forms that release harmful substances in the atmosphere. These fuel forms include petroleum and nuclear energy, which are used almost all over the world. Therefore, there is a need to develop sustainable energy sources that will help to reduce or curb these misfortunes. Biomass fuel is one vital source that has provided an alternative for averting these environmental issues.
There has been an increased reliance on petroleum, nuclear, and other sources of energy that are subjected to depletion. As these sources undergo depletion, the demand is continuing to increase, as a result of the ever increasing global population. This has increased the cost of accessing fuel and, therefore, the general cost of every commodity. This is because energy is essential in the production. The cost of living is increasing, dragging the economic development of countries and individuals. The use of sustainable and renewable sources of energy has provided a way of counteracting this challenge. Apart from hydroelectric power, solar energy and hydrogen energy, biomass fuel provides renewable and sustainable energy that doubles as environment-friendly. As long as people are continuing to use manufactured products, agricultural products, and rearing livestock, there is an assurance that biomass will always be available.
Biomass energy provides a way of cleaning the environment. Collection of plant and animal waste products provides a suitable and useful way of disposal of waste. Collection of agricultural and industrial waste has helped to avert environmental pollution. The waste products that would have been heaped on earth or let loose to pollute both soil and air are subjected to the economic use. Therefore, a system of energy production aimed at sustainability is used for industrial as well as domestic purposes.
Techniques used in harnessing energy from biomass have been noted to be less technical and less expensive, as compared to other energy harnessing techniques, such as oil refinery, nuclear energy production, and hydroelectric power plants. Therefore, this process provides a less expensive and easy way of energy generation, as long as the right conditions and requirements are met.
Available research for large scale commercial production on biomass energy is still limited. However, scientists are spending more time on involved projects to come up with highly productive techniques. There has been a slow pace in the way people are embracing this type of energy. This might be due to the tradition in many people that petroleum and nuclear energy are the most suitable energy forms. Automobile manufacturers should emphasize on making products that use this type of energy. The society should also be enlightened on the effects of over-relying on polluting and ever depleting energy sources.