Anaerobic Digestion
One of the main environmental problems of today's society is the ever-increasing generation of waste. In many countries waste prevention and reduction have become important political priorities and are an important part of efforts to reduce environmental pollution, reduce greenhouse gas emissions and mitigate global climate change. Past practices of uncontrolled waste disposal are no longer acceptable. Neither controlled disposal in the landfill nor the incineration of organic waste are preferable as technologies, as the environmental standards currently in force are much more stringent, with recovery and recycling of nutrients and organic matter being sought.
Biogas production from the anaerobic digestion of animal excreta and slurry and a wide range of organic waste converts these substrates into renewable energy and offers a natural fertilizer for agriculture. At the same time, removing the liquid organic fraction from waste streams increases the heating value of the remaining waste during incineration and stability in landfill sites.
Anaerobic digestion is a microbiological decomposition process of the organic substance, in the absence of oxygen, which is common in many natural environments and is currently applied to produce biogas in airtight reservoirs that act as reactors, commonly called digesters. A wide range of micro-organisms is involved in the anaerobic process that has two main end products: biogas and compost. Biogas is a gaseous fuel composed of methane, carbon dioxide and small amounts of other gases and trace elements. Compost is the digested substrate rich in nutrients and is thus used as a fertilizer for plants.
The production and collection of biogas from a biological process was first documented in the United Kingdom in 1895 (METCALF and EDDY, 1979). Since then, the process has been further developed and widely applied for waste treatment
water and the stabilization of the sludge. The energy crisis in the early 1970s raised interest in the use of renewable fuels, including biogas from anaerobic digestion. Interest in biogas has increased today due to global efforts to replace fossil fuels in renewable energy production and the need to find environmentally sustainable solutions
treatment and recycling of animal excreta and organic waste.
Biogas plants from anaerobic digestion, processing agricultural substrates (such as animal waste and pulp, plant waste, energy crops, organic waste from agro-industrial plants and the food industry) are some of its most important applications anaerobic digestion today. In Asia, several millions of very simple, small-scale biogas digesters are in operation in countries like China, India, Nepal and Vietnam producing biogas for cooking and lighting. Several thousands of agricultural anaerobic digestion plants are in operation in Europe and North America. Many of them are large-scale and high-tech, and their number has increased quite a lot in recent years. Only in Germany in 2007 were more than 3700 biogas plants.
Biogas from anaerobic digestion is an inexpensive and CO2-neutral source of renewable energy that offers the potential to utilize and recycle a wide range of agricultural residues and by-products, various bio-waste, industrial wastewater, and sewage sludge sustainable and environmentally friendly way. At the same time, it provides several socio-economic benefits for the whole of society as well as for the operators of biogas plants (farmers) involved.
Biogas production from the anaerobic digestion of animal excreta and slurry and a wide range of organic waste converts these substrates into renewable energy and offers a natural fertilizer for agriculture. At the same time, removing the liquid organic fraction from waste streams increases the heating value of the remaining waste during incineration and stability in landfill sites.
Anaerobic digestion is a microbiological decomposition process of the organic substance, in the absence of oxygen, which is common in many natural environments and is currently applied to produce biogas in airtight reservoirs that act as reactors, commonly called digesters. A wide range of micro-organisms is involved in the anaerobic process that has two main end products: biogas and compost. Biogas is a gaseous fuel composed of methane, carbon dioxide and small amounts of other gases and trace elements. Compost is the digested substrate rich in nutrients and is thus used as a fertilizer for plants.
The production and collection of biogas from a biological process was first documented in the United Kingdom in 1895 (METCALF and EDDY, 1979). Since then, the process has been further developed and widely applied for waste treatment
water and the stabilization of the sludge. The energy crisis in the early 1970s raised interest in the use of renewable fuels, including biogas from anaerobic digestion. Interest in biogas has increased today due to global efforts to replace fossil fuels in renewable energy production and the need to find environmentally sustainable solutions
treatment and recycling of animal excreta and organic waste.
Biogas plants from anaerobic digestion, processing agricultural substrates (such as animal waste and pulp, plant waste, energy crops, organic waste from agro-industrial plants and the food industry) are some of its most important applications anaerobic digestion today. In Asia, several millions of very simple, small-scale biogas digesters are in operation in countries like China, India, Nepal and Vietnam producing biogas for cooking and lighting. Several thousands of agricultural anaerobic digestion plants are in operation in Europe and North America. Many of them are large-scale and high-tech, and their number has increased quite a lot in recent years. Only in Germany in 2007 were more than 3700 biogas plants.
Biogas from anaerobic digestion is an inexpensive and CO2-neutral source of renewable energy that offers the potential to utilize and recycle a wide range of agricultural residues and by-products, various bio-waste, industrial wastewater, and sewage sludge sustainable and environmentally friendly way. At the same time, it provides several socio-economic benefits for the whole of society as well as for the operators of biogas plants (farmers) involved.
