The paper describes practical results of four-year laboratory studies completed to estimate technically feasible conditions of upgrading an existing sludge disposal system. A minimization of sludge mass and volume together with an energy recovery improvement were main goals of these activities. The way from lab studies and simulations to full scale investments has been shown with a special emphasis on application of respirometric procedure being applied by authors. Proposed was authors’ procedure for an estimation of a digestion time prediction for sludge of specific composition. Investigations completed at existing wastewater treatment plant resulted in practical implementation to be used during the design of upgrading and extension of the digestion and energy recovery system at the plant. It was proved that proposed changes provide close to optimum conditions for process performance and the application of proposed calculation procedures was adopted by design team
This paper presents characteristics of the Biovac® wastewater treatment plants operating in the mountain areas of the Polish national parks (NP): Tatrzanski NP and Babiogórski NP as well as in the West Spitsbergen NP. On the basis of the laboratory tests performed on raw sewage and the final effluent the efficiency of the wastewater treatment plants was evaluated. It was found that high COD values and rather high COD / BOD5 ratios were observed in the raw sewage during an off-peak tourist season. The research has also shown that the Biovac® treatment plants (SBR technology) showed a high level of removal of pollutants from sewage discharged from mountain hostels.