(478a) Enhanced Yield of Bio-Gas Production with Thermo-Reactor/digester Configuration and Separation of CO2

Pakistan is currently facing severe energy crisis with significant shortfall. A number of short-term technical solutions are available but are not adequate to solve the issue in the longer run. Production of bio-gas with modified thermo-reactor from the animal waste at regional level shows potential of reducing burden on total natural gas resource in Pakistan.

This research study investigates the effects of solar thermo-rector configuration on the overall yield and composition of bio-gas from dung.  The designed capacity of the bio-gas plant is 10 m³. The solar thermo-reactor employs internal heating system with coils using warm water heated from the solar energy. The bio-gas reactor was operated over the range of 25-55 ⁰C to observe effects on bio-gas yield and composition. It was observed that the increase in temperature within the thermo-reactor resulted in significant increase in yield of bio-gas i.e. thermo-reactor operated at 50-55 ⁰C (thermophilic). Operation time and plant size of state of the art process can be reduced.

The calorific value of bio-gas obtained at 50-55 ⁰C was slightly higher than calorific value of bio-gas obtained at mesophilic condition (25-35°C) due to increased production of CH₄. Thermophilic operation of bio-gas plant also enhances the methane content in the bio-gas i.e. 57-60 % vol of methane. Bio-gas produced was purged from bottom   and cold water from top a packed column and decreases in CO₂ was also recorded. The results were scaled up from pilot scale capacity to regional level in order to estimate potential of bio-gas production