Biogas

Biogas is formed in a process known as anaerobic digestion where organic material is decomposed by micro organisms in an oxygen free environment. In this process, many different micro organisms participate in several interactive and simultaneous processes resulting in the decomposition of complex organic compounds such as carbohydrates, fats and proteins. The final resultant products are methane and carbon dioxide. This is a natural phenomenon that can be observed in many environments with limited oxygen, such as in stomachs of cows, in bogs or rice paddies. Biogas can be used to provide heat, electricity or both. By removing other gases, biogas can be 'upgraded' to pure methane, often called biomethane. This biomethane can then be injected into the main gas grid and with its rich in nutrientsthe the remaining material can be used as a fertiliser. 

The main sources of biomethane are all untreated organic materials such as all animal excrements or waste landfills. Many forms of biomass are suitable for AD and among those the most common are: Sugar cane, green cuttings, maize-/grass- and whole-plant silage, corn, hay/straw, slops, grain tailings, glycerin, pomace, dry poultry droppings, poultry/turkey manure, cattle and pig manure, food waste, floating sludge, rumen/stomach content, slaughter wastes and blood. 

Through the usage of micro-organisms which digest the biomass a methane-rich biogas can be produced to generate renewable heat and power. This helps to cut fossil fuel use and reduce greenhouse gas emissions.

Biogas Benefits

Cleaner Environment 
We use the process of natural anaerobic digestion to produce our clean energy. As such, we do contribute to sustainable and clean environment. Producing biogas through anaerobic digestion reduces landfill waste, produces nutrient-rich liquid fertilizer, and requires less land than aerobic composting. We eliminate methane by disposing fermentable organic matter thereby reducing the emission of methane gas (CH4) into the atmosphere. Methane is 21 times stronger than carbon dioxide as a greenhouse gas. Through this process we produce clean and environment friendly fertilizers on organic basis.

Better Economics 
Biogas reduces the cost of complying with EPA combustion requirements for landfill gas and can create a source of income for farmers or food producers. Industries and citizens can become independent electricity and heat producers for their own needs. Alternatively, they can feed energy into the electricity and gas grids. This reduces a countries dependency on fossil fuels and helps to develop an competitve economy. 

Local Improvement 
Biogas compensates for traditional non-renewable resources, such as oil, coal and natural gas. Producing biogas creates jobs and benefits local communities. Citizens and industries make themselves independent from suppliers and save costs. 



Our Biogas Plants

The first step in the Anaerobic Digestion (AD) process is when biomass is put inside a digester. It is the same process that occurs in the stomach of a cow. A similar process is exploited in a digester, where organic material such as crops or food waste is put into an air-tight digestion container. This procedure can be divided into three main steps: hydrolysis, fermentation and methane formation. First, micro organisms decompose complex organic compounds to simpler compounds such as sugar and amino acids. In a second step, a number of intermediate products are formed, including alcohols, fatty acids and hydrogen gas. Finally, methane is formed by a unique group of micro organisms and produces the raw biogas that mainly consists of methane and carbon dioxide.

In order to use biogas as a substitute for fossil fuel, its energy content must first be increased by removing carbon dioxide, a process known as gas up-gradation. In an up-gradation plant water and contaminants must be removed.

Green Elephant operates with large-scale as well mid-scale biogas plants (GreenBox™). We us pumps to load the raw materials. To store the gas and protect it against weather we use digesters with up to four stirring devices and double membrane roofs.

AD is not a new technology, it has been already used since the late 1800s. Nonetheless, now an increasing number of AD plants are being built worldwide to generate clean renewable energy. Mid-scale biogas plants, such as the GreenBox™, are also used to treat the waste produced in homes, farms and supermarkets. This helps divert waste from landfill. 

Courtesy:greenelephantindia