Power generation with biogas from landfills
Elimination of landfill gas and convertion to electrical and thermal energy
Decomposing waste in the landfills results in biogas and the associated odor and emission hazards. The chemical composition of this gas consists of 45-60% methane (CH4), 25-35% carbon dioxide (CO2), and 10-20% nitrogen.
Landfill gas recuperation system
Biogas collection takes place in wells equipped with drilled pipes. This allows biogas to leave the well and be measured, controlled, dehydrated and treated. After this process the biogas is the fuel for the Guascor Power power modules. Therefore it is produced electricity from the waste.
Generation of electricity and heat with Guascor Power power modules fueled with sewage gas
Elimination and use of the biogas from the water sewage treatment plants
The treatment of the residual municipal water is a complicated process of purification and filtration. Prior to dump this treated water into rivers the contaminating elements are cleaned. Part of the residues of the process is a biodegradable material that is stored after filtration and decantation.
The fermentation of the sludge results in a biogas containing 55-65% methane (CH4), 30-40% carbon dioxide (CO2) and other gases. Traditionally these gases have been treated and stored in gas plants and then used to heat the stored sludge. Modern installations store these gases after treatment to remove the corrosive and contaminating elements, then they are used to power internal combustion engines specially designed for this type of fuel. These engines generate electricity to supply power to the plant equipment.
Biomethanization
Biomethanisation is the anaerobic digestion of different types of waste and effluents
- Agriculture (corn, tapioca, etc.)
- Forestry
- Livestock (pork, poultry, etc.)
The controlled anaerobic digestion process is one of the processes suitable for reducing greenhouse gas emissions, harnessing energy from organic waste and maintaining and improving upon the fertiliser value of the treated products.
Anaerobic digestion can be applied to cattle and agricultural waste, among others, and to waste from the industries that process such products. Some of the types of waste that can be cited are purines, manure, agricultural waste, crop surpluses, etc. Such waste can be treated separately or together, through the process known as codigestion.
Anaerobic digestion is also an appropriate process for treating waste water with a high organic load, such as that produced by many food industries.
The benefits associated with anaerobic digestion are:
- Significant reduction of bad odours,
- Mineralisation,
- Renewable energy production if the gas is harnessed as energy and replaces a source of fossil energy,
- Reduction of greenhouse gas emissions deriving from the reduction of uncontrolled CH4 emissions, (which produce a greenhouse effect 20 times greater than CO2), and reduction of the CO2 saved by replacing fossil energy sources.
Promoting and implementing collective biogas production systems (several farms) and codigestion systems (joint treatment of organic waste from different origins within a geographical area, usually agricultural and industrial) also makes it possible to implement comprehensive organic waste management systems for different geographical areas, with social, economic and environmental benefits.
Anaerobic digestion can be performed with one or more types of waste. The only requirements are that they must be liquids containing fermentable material, and must have a relatively stable composition and concentration. Codigestion is a technological variation that can solve problems or make up for elements that are lacking in one type of waste, if they are compensated by the characteristics of another.
An ideal situation would be to install a small cogeneration system, which would result in savings on hot water and electricity during cold periods, along with a connection to the grid for the sale of electrical energy. During the summer months, energy could be sold to the electrical grid, or biogas could be sold for bottling as compressed gas.
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