Biosolids management is one of the most challenging aspects of municipal wastewater treatment. But the Varcor system, a process developed by Sedron Technologies, is designed as a complete, holistic solids handling system that delivers a dried Class A product with multiple potential end uses.
The system is based on mechanical vapor recompression where solid and liquid fractions are separated through thermal evaporation and the resulting vapor is mechanically compressed. The compressed vapor is then used as the heat source for the evaporation process; in transferring its heat, the vapor condenses and forms a water output. The remaining vapor is concentrated and condensed into a solution of low boiling point constituents. Due to thermal processing, all three outputs — the water, the solids and the low boiling point constituents — are pathogen free.
“The Varcor has multiple applications in the municipal wastewater treatment industry including the treatment of Class B biosolids into Class A EQ or Class AA biosolid, reduction of nutrient loading by removing nitrogen and phosphorus from sidestream discharges to public waterways and processing of septage waste,” says Tim Evenson, vice president of sales for Sedron Technologies. “The best fit would be at a high-volume treatment plant that has to meet discharge limits, or would like to produce high quality Class EQ biosolids at an attractive cost with no public funding.”
The system uses a mechanical and thermal process that delivers both environmental and commercial benefits by eliminating the use of chemicals, the need for cross-state hauling of liquid waste, and land application of biosolids. It also involves using less energy than traditional treatment processes, furthering the environmental benefits of the system. Finally, the new facility produces both pathogen-free solid fertilizers and aqueous nitrogen fertilizers that can be used as key inputs in agriculture. It transforms traditional wastewater processes that can have a negative impact on the environment into upcycling processes that deliver environmentally beneficial outputs.
“We currently have one operating Varcor system processing human waste in a suburb just south of Seattle, Washington,” says Evenson. “The feedback from customers, including septic haulers and plants who are providing biosolids to the site for processing has been overwhelmingly positive. We are saving them a significant sum of money, reducing trucking miles and time, and providing a solution that is better for the environment.”
360-399-6193; www.sedron.com
