Bio gas is a sustainable alternative for fossil fuels. This also provides a solution to biowastes. There are various designs for the efficient production of biogas. Majority of biogas generation units use animal wastes as feed material.
Plug flow type biogas digester was identified as more suitable for using non conventional feed stocks like green vegetations, municipal waste for the biogas production. These digesters have been reported to be more efficient in converting feed stocks with higher total solids content.
The aim of this study was to investigate the variables associated with plug flow biogas digesters and to determine the operational parameters that will give optimum biogas production. In the study three feed rates were used.
The highest specific methane production of 0.341m3/kgVS per day was observed at feeding rate of 1.4kg per day. Highest VS reduction of 91.37% was observed at feeding rate of 1.4 kg per day. VFA profile and pH profile along the digester length showed the distribution of biogas production stages along the length of the digester especially at lower feed rates.
Author: Perera, Upuli