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Rapid Sludge Solidification & Excavation from Aeration Basins

Rapid Sludge Solidification & Excavation from Aeration BasinsWhen a major U.S.-based municipal wastewater utility contractor needed a rapid, money-saving, and efficient solution for removing 1,000+ tons of saturated sludge from an aeration basin, they turned to ZapZorb superabsorbent polymers (SAPs).  

The aeration basin required maintenance to restore its maximum treatment capacity, which was reduced due to accumulated sludge.

 ZapZorb allowed the contractor to:

  • Minimize the time spent drying and excavating sludge on a time-sensitive project
  • Meet landfill requirements for disposal with minimal special disposal costs
  • Ensure that the waste material leaving the site passed the EPA’s paint filter test and was contained no free liquid.


📹Video: Watch the entire sludge solidification process


If the contractor had chosen to manually dry the sludge, an additional week would have been added to the already compressed schedule, resulting in additional labor costs, and added stress on the wastewater treatment process downstream of the basins.  ZapZorb SAPs typically achieve full solidification of WWTP sludge within 15-20 minutes.  

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To remove approximately 1,100 tons of saturated sludge, ZapZorb Premium SAP was applied by the contractor at a dosage rate of 0.7% (8 tons of SAP), or about $600 in added disposal weight.  By comparison, 1,000-2,000 tons of sawdust ($70,000-$140,000 in disposal weight), or 100-300 tons of cement would be required to eliminate the free liquid from the same sludge.   ($7,000-$21,000 in disposal weight).

ZapZorb SAPs not only absorb huge volumes of liquid waste, SAPs also retain the absorbed liquid even under vibrations and moderate pressure, like those experienced inside a dump truck bed during transportation, and the pressure applied to waste that is placed inside a landfill.  SAPs offer permanent solidification.

“Rather than looking for the cheapest solution, we opted for what we know works.”

--Project Manager

The next time saturated sludge stands in your way of completing a project, let ZapZorb clear your path so that you can focus on the finish line.

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