Biosolids technology helps Idaho City meet sludge disposal requirements
The city of Rexburg, Idaho, has selected the GE’s Monsal advanced anaerobic digestion technologies to treat biosolids at the city’s wastewater treatment facility...
The city of Rexburg, Idaho, has selected the GE’s Monsal advanced anaerobic digestion technologies to treat biosolids at the city’s wastewater treatment facility.
Located 28 miles northeast of Idaho Falls, the city of Rexburg needed a new solution to treat sludge from the wastewater treatment plant prior to landfill disposal in order to ensure it complied with the Environmental Protection Agency (EPA) sludge disposal standards.
The project represents the first North American application of the Monsal technologies, a private UK-based water, waste, advanced anaerobic digestion and integrated biogas-to-energy business, after GE acquired the business in July 2014 (read WaterWorld story).
An aanaerobic digestion process will be used to treat biosolids and GE’s Monsal 70 system will pasteurize the sludge, creating “Class A” biosolids for disposal.
The EPA governs biosolids under the Part 503 rule. Biosolids that have gone through an accredited process, defined in 40 CFR Part 503 for pathogen reduction, are deemed to be “Class A”. With this classification, no land application restrictions exist.
Biogas generated from the anaerobic digestion process will be used to fuel the pasteurization boilers. A heat recovery system is being installed to capture and convert the biogas to heat, with a separate contractor set to supply the building and installation of the piping and ancillary systems.
Aqua Engineering, the design engineer on the project, worked closely with the city of Rexburg and GE to fit the technology into the existing footprint of the city’s wastewater treatment plant.
GE is scheduled to deliver its equipment by fall 2015, and the digestion system is expected to begin operating in late 2015.