Material removed by the fine screens is chopped, dewatered, and compacted before being placed in a dumpster for transport to a land fill.

Compacter

Conveyor

Dumpster

The sand, gravel, and other inorganic solids that have been removed in the grit chambers are pumped to dewatering equipment.  The dewatered grit is placed in a dumpster and is taken to a land fill.

In the gravity sludge thickeners, the sludge is concentrated by settling the heavier material to the bottom.  The water flowing over the top is recycled through the plant for further treatment.

Most of the activated sludge-microorganisms from the final clarifiers is returned to aeration tanks to keep the treatment process biologically active.  Excess activated sludge is concentrated in dissolved air flotation thickeners that use tiny air bubbles to float the solids to the water's surface where skimmers remove it.  Water removed is recycled through the treatment plant.

After thickening, primary and secondary sludges are combined and sent to sludge digesters.  Here anaerobic bacteria that live without air further decompose and stabilize the biosolids.  Methane gas produced in this process is recycled as fuel for engines that power a blower and electric generators.  The water used to cool these engines is used to heat the digesters and several buildings at the plant.

To reduce the volume of biosolids, They are thickened on a gravity belt thickener.  The Water removed is recycled through the plant for further treatment.

After 15 to 20 days in the digesters, the biosolids are ready for land application as Metrogro.  The plant produces 100,000 gallons of Metrogro per day.  Three 6.4 million gallon storage tanks hold the biosolid material until it can be hauled to area farmlands for application as fertilizer.

Tanks

Applicator