Treatment of Biosolids for the Production of Biofuels under Controlled Environment

Biosolids from the Fredericton wastewater treatment plant were tested and analyzed to evaluate their utilization as a source of renewable energy. The optimum reaction conditions for the production of biofuels (temperature, heat rate, humidity, and particle size and residence time) were determined with the purpose to obtain optimum yields. A yield of 82% char with an average heating value in the range of 7,800 Btu/lb (18,000 kJ/kg) was obtained at lower temperatures in the range of 200 °C with low heating rate in the vicinity of 0.08 °C/sec. Increasing reaction temperature up to 400 °C with low heating rate in the vicinity of 0.08 °C/sec increased yield of bio-oil up to 16% with a heating value in the range of 18,000 Btu/lb (41,000 kJ/kg). Mixing the bio-oil obtained with the char did enhance heat value of char. Pelletizing the products to facilitate handling and transport was also assessed and showed encouraging results. Finally, characterization of biofuels was also performed. Biofuels obtained from biosolids proved to be a good source of renewable energy.