Abstract
Anaerobic digesters (AD) are important biogas production units that convert waste to energy. In this paper, the water recycling will be investigated in the digestate of the AD as a way to utilize the scarce resources. Mostly, the digestate are put in dry bed for water vaporization and recovery of the solid bio-fertilizer. This paper focusses not only on extracting of the solid content, but it also focusses on capturing water such that it can be reused in the anaerobic digestion system. The tests that were performed are the accumulated mass, water quantity and water quality tests. The experimental matrix for testing were also designed. In the results, it was determined that most suitable material was 60 micrometre stainless steel mesh. This material was found to have a separation efficiency of 44% while recycling 77% of the water from liquid digestate. The material’s properties had a high durability, high corrosion resistance and high strength. This made the material long lasting and efficient for real life applications and due to its low corrosion, the recycled water does not have material impurities. The filtered water can be fed back into the digester while the filtrate can be used as a fertilizer.