Biofuel application of biomass obtained from a meat industry wastewater plant through the flotation process—A case study

Physicochemical treatment of meat industry wastewater is used to increase the organic matter removal efficiency, and it generates great amounts of sludge. Treatment using commercial ferric sulfate as coagulant for this specific wastewater gave high organic matter removals, decreasing considerably the amount of waste material to be treated in biological systems, and also allowing the obtention of 0.83–0.87 kg of biomass fuel for each m3 of treated wastewater. Due to sanitary, environmental problems and operational costs related to the discharge, land disposal and re-use of wastes, the utilization of this Biofuel (dried sludge) for steam generation has shown to be a viable alternative. This type of fuel has a high heating value, and it is a renewable energy source. The combustion test with a Biofuel to sawdust ratio of 4:1 met the technical requirements for the characterization of this promising fuel; nevertheless, operating conditions must be well designed to achieve NOX and SO2 emissions below local and/or international limits.