AGF

An AGF unit has been in place for approximately a year at the Salmon Creek Plant. It has been operated in a number of process configurations. A flotation unit was installed in an available tank.The primary digester was connected to saturation pumps, which pump solids to the flotation unit.

While a full report is being composed, there is significant agreement on the following:

• AGF has increased volatile solids destruction from approximately 50% to 71% based on mass balance.
• There has been a reduction in total hualage by 34%.
• Belt pressed solids density has improved from 16% to 18.5% .
• Belt press odors have been effectively eliminated.
• The use of polymer on the belt presses has been reduced. Total polymer usage is about the same for the average regimen since some polymer is used in the flotation process.
• Belt press operations have been reduced from 4.0 days per week to 1.5 days per week, a 63% reduction.
• Plant operations, which used to experience frequent foaming incidents, have been improved. There have been no foaming incidents since AGF was installed.

Flotation Unit ~18 ft in diameter by 8 ft deep. This and the saturation pumps are the core of the AGF.
Saturation Pumps with polymer feed in orange. Dennis Burke on left. NY visitor on right.
Flotation Unit's effluent--note clarity. Foam due to entrained gas fizzing upon being removed from pressurized line.
Belt Press Operation--AGF solids being dumped into truck bed Note solids consistency and density, solids are basically odorless.

Pasteurization

The pasteurization process has been benched-piloted by the SouthWest Suburban Sewer District's staff. That bench model has validated the process. The process produces an odor free Class A biomass. The full scale pasteurization process is currently being implemented. The pilot and the full scale plant will be reported on shortly.

Boiler for heating water to temperature for subsequent injection into Pasteurization Unit
Pasteurization Unit, solids are batch pasteurized under control of a supervisory control system. Pasteurized solids, pathogen free, are sent to a small digester where the destroyed bacteria are consumed by food based bacteria.