ARTI Biogas

Compact ARTI digester using waste foodstuffs  

There are many people of course who don’t have livestock or who live in an urban environment where the two conventional systems discussed above are not appropriate and cannot be utilised. If you live in a built up area, the ARTI system is for you! 

The Indian Appropriate Rural Technology Institute (ARTI) has developed a small biogas digester that uses starchy or sugary wastes as feedstock, including waste flour, vegetable residues, waste food, fruit peelings, rotten fruit, oil cake, rhizomes of banana, canna (a plant similar to a lily but rich in starch), and non-edible seeds. 

These household digesters have a small footprint and are made from cut-down high-density polythene (HDPE) water tanks. A heat gun can be used to make them and standard HDPE fittings can be used. The standard plant uses two tanks, with volumes of typically around 0.75 m3. The smaller tank on top is the gas holder and is inverted over the larger fermenter so it telescopes inside. It is the fermenter which holds the mixture of decomposing feedstock and water. 

For best results the feedstock (stuff you put in the fermenter) should be blended so that it is smooth. The feeding of the plant is built up over a few weeks until it provides a steady supply of gas, typically 250-500 g of gas per day from 1-2 kg (dry matter) of feed. An inlet is provided for adding feedstock, and an overflow for removing the digested residue. The digester is set up in a sunny place close to the kitchen, and a pipe takes the biogas to the kitchen. The member’s area of Build-A-Biogas-Plant has more information on design, construction and operation of an ARTI style biogas digester.