Potential Use of Sludge from Potato Processing Industry WWTP as a Co-substrate in Anaerobic Digestion of Organic Fraction of Municipal Solid Waste

This paper presents the results of a preliminary study on the characteristics, methane production potential and solids elimination potential of sludge resulting from aerobic treatment of potato industry wastewater (later be called potato sludge). The results of this study are considered important to examine the suitability of potato sludge as a co-substrate in anaerobic digestion of Organic Fraction of Municipal Solid Waste (OFMSW). From this study, it was revealed that potato sludge has relatively high organic matter content. The volatile solids content of the sludge reached about 22 % of the total weight. It had a maximum methane production of around 0.40 m3 CH4 kg-1VS. More than 80 % of its maximum methane production in batch assays was achieved within the first 4 days of incubation indicating that it was easily degradable. The concentrations of heavy metals in the potato sludge were lower than the inhibitory or toxic concentration limit. More than 70 % of its volatile solids were eliminated during solid elimination tests. Therefore, potato sludge is considered as suitable for anaerobic digestion either as a sole substrate or co-substrate.