Introduction
The name “Biomass” was invented in 1975 to describe natural materials used as energy sources and refers to organic matter that can be converted into energy. Biomass energy is the oldest energy source in human history, easily dating back to man’s first fire.
From the information and data currently available on biomass, its supply currently accounts for 14% of the world’s energy sources. (IENICA, 2007). In developing countries 40% of energy is derived from biomass, while in the US it represents 4%, Sweden 14% and Austria 10% (Hall et al. 1992).
The process
In biomass, a process called photosynthesis allows plants to capture sunlight and transform it into chemical energy, as shown in this equation:
CO2 + 2H2 heat light([CH2O] + H2O) + O2
The organic resources that are used to produce energy through these processes are collectively called “biomass”.
The elements
The main chemical elements of biomass are carbon and hydrogen, in addition to others, such as oxygen, nitrogen and sulfur. The latter element, however, exists only in very small amounts.
Energy
Biomass energy can be obtained by reversing the process of photosynthesis. Stored energy is released when chemical compounds within biomass materials are broken down.
Biomass is a good source of renewable energy but generally speaking it is not a good fuel as it typically contains more than 70% air and void space. therefore, this low volumetric energy density makes it difficult to collect, ship, store, and use.
types of biomass
Biomass includes forestry and mill residues, agricultural crops and waste, wood and wood waste, animal waste, waste from livestock operations, aquatic plants, fast-growing trees and plants, and municipal and industrial waste.
Therefore, various types of organic materials can be burned to produce energy or turned into a gas that can be used as fuel.
Research in this area has shown that the net energy available in biomass materials when burned ranges from about 8 MJ/kg for green wood, 20 MJ/kg for oven-dried plant matter, and 55 MJ/kg for methane; compared to around 23 – 30MJ/kg for coal (Fletcher S., et al., 2005).
Types of biomass energy
Biomass energy can be divided into two categories: modern biomass and traditional biomass. In most cases, modern biomass involves large-scale uses as it seeks to replace conventional fossil fuel energy sources still used in various parts of the world. These large-scale uses may include forest wood and agricultural residues, urban waste, biogas, and energy crops. Most of the traditional biomass is generally found in developing countries. Biomass materials in this case can include various types of wood, charcoal, rice hulls, animal manure, and other plant residues (Fletcher S., et al. 2005).
There are two main options available for the use of biomass:
1. Independent construction (or dedicated biomass): are defined in the Renewable Obligation as those that have been put into service since January 1, 1990 and are “powered entirely by biomass in any month” (dti Carbon Abatement, Technology Program 2005). 2. Co-combustion of biomass with other fuels.
We know that 40% of the European Union’s energy supply depends on oil imported from OPEC countries. Various investigations and studies predict that in the coming years there will be a greater dependence on oil and gas imports, this will translate into the participation of imports into the European Union (EU) up to 70% by 2030 (Ignaciuk A., et al. 2004).
Plants “Energy Crops” Examples
Generally speaking, any type of energy crop can be used as biomass material for the purpose of power generation, however, considering that the goal of various biomass projects in general and this project in particular is to generate economically viable power on a commercial scale, then the selection process to choose the most suitable biomass materials would have to undergo strict tests from scientific and technical factors to market, commercial and regulatory factors. Having said that, there are currently a number of popular examples currently being investigated and/or used as examples of the types of biomass materials with possible future commercial use. One of these examples is “Scrub Rotation Shorts” (Defra. Department of the Environment, Food and Rural Affairs 2002). The following are some popular examples:
1. Alfalfa (nitrogen fixed in the soil).
2. Willow.
3. Switch grass (protects soil and water in the basin).
4. There is a wide range of crops that can be used for biodiesel production,
such as canola (rapeseed), palm oil, sunflower oil, soybean oil, animal oil
fat (tallow) as well as recycled oil (eg frying oil).
5. Common crop residues (waste matter).
6. Sorghum.
7. Forest Crops – Fast growing trees, which should be suitable for regrowth. Regrowth involves harvesting the tree after a few years and then allowing the tree to sprout from the stump again, followed by subsequent harvesting (usually between 2-5 year periods).
8. Forest Residues – Generated by operations, for example, thinning of plantations, natural attrition, extraction of logs for pulp and cleaning for logging roads. Various types of woodworking can also generate large volumes of waste, such as sawdust, bark, and wood chip debris and trimmings. There are many of these types of derivative materials, but they are not generally used.
conclusion
Biomass in general, among other renewable sources of energy, is the science and technology for a new type of energy that many predict will be the challenge during the 21st century. The research and investigations of various biomass materials, for long-term commercial global fuel use, is today’s challenge and the investment for the near future. This research is expected to produce the materials and technologies needed to replace fossil fuels, particularly crude oil, which will run out sooner or later.
