The use of waste food instead of dung as feedstock makes this biogas plant distinct and more practical to use by people in both rural and urban areas
What comes to your mind first when “a biogas plant” is mentioned? Does the picture include a large smelly tank attached to a gas stove used mostly in villages?
Well, you might have been correct if not for an innovative compact biogas plant that uses waste food rather than cattle dung as the feedstock! Brainchild of Dr Anand Karve, a Pune-based biologist, this biogas plant can be used both in rural and urban households, thanks to the source of energy.
The use of biogas – a mixture of mainly methane and some carbon dioxide – as an alternative to conventional fuels such as coal and LPG in rural households is not new. However, the size of the plant and its reliance on large quantities of cattle dung has acted as a dampener for urban households. Also, because of the dung’s low calorific value, the energy produced per kilogram of dung is low vis-à-vis waste food. It was this that made Dr Karve decide on replacing the traditional feedstock with waste food as the input. “It is known that methane gas can be produced from sugar, starch, cellulose and fat, and one kg of food waste (dry weight) – which contains starch, sugar, protein or fat – yields about 250 gms of methane. So I decided to replace dung used in a conventional biogas plant with waste food,” says Dr Karve, who runs Appropriate Rural Technology Institute (ARTI), an NGO. The result was an efficient and less cumbersome device that can also be used in urban households.
Since 2006, nearly 3,000 such plants have been installed both in India and abroad in rural and urban households and in commercial establishments such as hostels and hotels.
BenefitsSo why has this biogas plant aroused a lot of interest? There are several reasons behind this.
One, the conventional biogas plant produces 250 gms of biogas from 40 kgs of excreta in 40 days. In contrast, the new plant requires just 1 kg of sugar or starch – in the form of waste food from household or hotels, spoilt grain, overripe fruit, non-edible seeds, kitchen waste, etc. – to produce the same quantity of methane in just 24 hours. According to Dr Karve, through the use of this compact system it has been demonstrated that using feedstock having higher calorific value increases the efficiency of methane generation.
Two, the choice of feedstock facilitates its use in urban households. Reliance on cattle excreta has been one of the major restricting factors limiting its usage in urban homes. Traditional plants require approximately 40 kg of input on a daily basis, and have a high retention period of 40 days. The large quantity of input and the longer period require plenty of storage space, which is a major constraint in cities.
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How does it work?
The standard plant uses two tanks, which typically have a volume of 0.75 cu.m. and 1 cu.m. The smaller tank, which is the gas holder, is inverted over the larger one containing a mixture of feedstock and water. An inlet pipe is provided for adding feedstock and an overflow pipe for removing the digested residue.
A pipe takes the biogas to the kitchen, where it is used with a biogas stove.
The gas holder gradually rises as gas is produced, and sinks down again as the gas is used for cooking.
Initially the plant is fed with a starter mix, which contains either cattle dung mixed with water and waste flour or effluent from an existing biogas plant mixed with starch. The feeding of the plant is built up over a few weeks.
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hree, according to Dr. Karve the higher calorific value of the input results in better quality of gas thus produced. From the point of view of conversion of feedstock into methane, this system is 400 times more efficient than conventional system. He says, the biogas thus produced has all the virtues of LPG – it produces a clean blue flame, has the same intensity, provides finger tip control of flame, produces no soot and smoke, etc. As methane has the same calorific value as LPG, it becomes as efficient and cost effective too.
Source:http://www.dare.co.in/people/featured-innovation/a-better-biogas-plant-for-your-home.htm
What comes to your mind first when “a biogas plant” is mentioned? Does the picture include a large smelly tank attached to a gas stove used mostly in villages?
Well, you might have been correct if not for an innovative compact biogas plant that uses waste food rather than cattle dung as the feedstock! Brainchild of Dr Anand Karve, a Pune-based biologist, this biogas plant can be used both in rural and urban households, thanks to the source of energy.
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| Dr Anand Karve Appropriate Rural Technology Institute (ARTI) |
Since 2006, nearly 3,000 such plants have been installed both in India and abroad in rural and urban households and in commercial establishments such as hostels and hotels.
BenefitsSo why has this biogas plant aroused a lot of interest? There are several reasons behind this.
One, the conventional biogas plant produces 250 gms of biogas from 40 kgs of excreta in 40 days. In contrast, the new plant requires just 1 kg of sugar or starch – in the form of waste food from household or hotels, spoilt grain, overripe fruit, non-edible seeds, kitchen waste, etc. – to produce the same quantity of methane in just 24 hours. According to Dr Karve, through the use of this compact system it has been demonstrated that using feedstock having higher calorific value increases the efficiency of methane generation.
Two, the choice of feedstock facilitates its use in urban households. Reliance on cattle excreta has been one of the major restricting factors limiting its usage in urban homes. Traditional plants require approximately 40 kg of input on a daily basis, and have a high retention period of 40 days. The large quantity of input and the longer period require plenty of storage space, which is a major constraint in cities.
==============================================
How does it work?
The standard plant uses two tanks, which typically have a volume of 0.75 cu.m. and 1 cu.m. The smaller tank, which is the gas holder, is inverted over the larger one containing a mixture of feedstock and water. An inlet pipe is provided for adding feedstock and an overflow pipe for removing the digested residue.
A pipe takes the biogas to the kitchen, where it is used with a biogas stove.
The gas holder gradually rises as gas is produced, and sinks down again as the gas is used for cooking.
Initially the plant is fed with a starter mix, which contains either cattle dung mixed with water and waste flour or effluent from an existing biogas plant mixed with starch. The feeding of the plant is built up over a few weeks.
==================================================
hree, according to Dr. Karve the higher calorific value of the input results in better quality of gas thus produced. From the point of view of conversion of feedstock into methane, this system is 400 times more efficient than conventional system. He says, the biogas thus produced has all the virtues of LPG – it produces a clean blue flame, has the same intensity, provides finger tip control of flame, produces no soot and smoke, etc. As methane has the same calorific value as LPG, it becomes as efficient and cost effective too.
Source:http://www.dare.co.in/people/featured-innovation/a-better-biogas-plant-for-your-home.htm
