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Innovative technologies combining dewatering and drying in one device are becoming attractive in municipal biosolids and residuals processing. One technology is J-Vap®, which is drying the solids using heated water while under pressure and applying vacuum to the filtrate. The objective of this study was to demonstrate that the squeezing pressure combined with negative vacuum pressure and temperature increase would lead to pathogen inactivation without necessarily meeting the time/temperature requirements set in the USEPA Part 503 requirements for pasteurization. The paper presents pilot scale results from experiments on a prototype of the technology. Anaerobically digested biosolids from a full scale conventional activated sludge plant, were spiked with pathogens or pathogen indicator organisms, such that the process could be approved by the U.S. EPA's Pathogen Equivalency Committee (PEC) as a process that produces Class A biosolids. The spikes included both viruses and helminth eggs. Operating parameters were monitored to determine the conditions that could lead to pathogen disinfection.Results showed that Class A biosolids are achieved when the process is ran under typical operating conditions, and where the monitored solids temperature was maintained at above 50 o C for over 3 hours. Additional types of biosolids or residuals that have undergone different wastewater treatment processes must be tested to obtain national certification and to assure validation of the disinfection.

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The feasibility of using electrokinetic processes for dewatering and pathogen inactivation of biosolids was evaluated on a bench scale. Raw primary sludge blended with the secondary biological sludge from the wastewater treatment plant in Laval (Quebec) was used. Six electrokinetic cells have been used in this study and a conditioner was also added to two cells. Potential gradients of 0.5, 1.0, and 1.5 V/cm were applied to the cells. Electrical parameters were measured and water was collected from the cathode area. Results showed the capability of dewatering to 62% TS or 38% water content. The highest solids content was achieved in the cell with the higher voltage in the presence of the conditioner. No fecal coliforms were observed in cells with conditioner. Under optimal operating conditions, the cell with a potential gradient of 1.5 V/cm exhibited the consumption of energy at 220 kWh/m 3 of biosolids. This method of dewatering appeared to have technical and economic merit and warrants further investigation.