The development of anaerobic biotechnology for treatment of wastewater has led to new configurations of bioreactors, which have as an important feature the establishment of favorable conditions for the fixation of biomass that will degrade organic material present in wastewaters. Characteristics such as high resistance to biological degradation and high mechanical strength, coupled to cellular structure make ceramic foams an excellent option for the production of supports for biomass immobilization. In this work, the gelcasting process in association with the aeration of a ceramic suspension was used as a route to produce ceramic foam supports. Alumina and caulinite, which are materials that have, respectively, positive and negative surface charges at the pH range used in bioreactors, were used as raw materials. After sintering, the foams had their porosity and permeability characterized, and then were submitted to a cycle of 35 days in a differential reactor, fed with synthetic domestic wastewater. Other materials, like expanded clay and ethylene-propylene rubber (EPR) were also submitted to the same tests for the purpose of comparison. Results allowed the evaluation of advantages and disadvantages of ceramic foams as supports for the immobilization of microorganisms in comparison to other materials.
ceramic foam; gelcasting; wastewater; anaerobic reactor; biofilm
