Plastic biodigesters – a systematic study

• Published in: Energy for sustainable development 2005-12, Vol.9 (4), p.40-49
• Main Authors: Kumar, K. Vinoth, Bai, R. Kasturi
• Format: Article
• Language: English
• ISSN: 0973-0826
• DOI: 10.1016/S0973-0826(08)60498-6

Plastic cans with the capacity of 5 litres (l) were converted into biogas digesters. Batch-mode performance was studied on three parameters, viz., colour of coating, material of fabrication, and two different atmospheric conditions. Two experiments were undertaken on the basis of their performance and further compared over different fabricating materials. One set was done outdoors and another set under indoor conditions as control. In both experiments, the fresh matter (cowdung) added was 0.025 kg per day and both the studies were carried out over a period of 40 days. All the experiments were repeated thrice and their average readings were tabulated and represented graphically. From the performance study, the gas yield was found to be 15 and 22 % higher in a black-coated plastic biodigester than in translucent and control biodigesters respectively. From the comparative study, the gas yield was found to be 50, 18, 22, 42, 71 and 65 % higher in the black-coated plastic biodigester than in tin, black-coated tin, translucent plastic, brown-coloured plastic, transparent plastic and glass biodigesters respectively in the outdoor experimentation. Similarly, it was noted that the gas yield in the translucent plastic biodigester was 55, 10, 67 and 66 % higher than in tin, brown-coloured plastic, transparent plastic and glass biodigesters respectively in the indoor experimentation. The results revealed that the black-coated translucent can digester showed better performance with higher methane composition in both the experimental studies and it can be concluded that plastic gave the best performance with its optimum heat transfer property under day-night conditions.