GEM System - Drier Sludge with the “Floc Seeding” Method

Since the GEM System dissolves air under pressure before the floc is formed, dissolved air is inherently part of the floc structure once it is formed.

While the floc is being formed in the LSGM heads, the water is kept under pressure, which keeps the air in a dissolved state.  Air can only be entrained inside a floc structure while sufficient pressure exists and the air remains in a dissolved state.  After the dissolved air becomes part of the floc structure (once the air pressure drops), the air within the floc structure comes out of solution.  When this happens, the air bubbles expand and push out water from the floc, creating much drier sludge.

This Floc Seeding process creates “hollow” flocs, which are very buoyant and float independently.  The Floc Seeding process produces much drier sludge than a “Collision Method” process that a typical DAF System uses, which only attach large air bubbles to the outside of a floc structure in a floatation tank.  A Collision Method process will leave water trapped inside a floc structure, making the sludge heavier with water.  In addition to less dry sludge, a DAF system will produce sludge that will lose the attachment of its air bubbles over time, which causes sludge to eventually sink as well as floc carry-over/sedimentation.

Sludge samples in our showroom taken from the GEM System are still floating, with most of the samples being several years old.

Another additional benefit of the GEM System’s sludge is its effective decant-ability.  Since air is trapped inside the sludge, it will stay afloat indefinitely.  This eliminates sludge settling to the bottom of a sludge storage tank, and allows operators to decant off free water.  Decanting off free water further reduces hauling costs.

If the GEM System’s sludge is treated through the use of equipment such as centrifuges or belt filter presses, much less energy is required to treat the sludge to a certain point.

Since the GEM System produces much drier sludge, far less sludge is produced per gallon of water treated.  This significantly reduces hauling costs for whichever wastewater operation the GEM System is implemented.

Water Technology