Sewage Sludge Treatment With Application Of The GACS Method Of Zeologic S.A.

General Information
During treatment of liquid wastewater, certain byproducts are produced simultaneously, such as shreds, sand, shrubs, and excess sludge from sedimentation tanks (primary and secondary). From these byproducts, the major in volume and in means of handling and disposal is the sludge.
Sludge of this type, is a completely watery mass, that its content in solid substances is estimated around 3-5‰. Due to its high volume and components, is responsible for major environmental issues that are non-solvable to this day, concerning its final disposal. For that reason all applied sludge treatment procedures like condensation, improvement and dehydration are aiming mainly at the removal of major part of the water and reducing its total volume, without providing a final solution to this issue.
The GACS Solution (Geochemical Active Clay Sediment)
The Geochemical Method GACS consists an innovative solution on an international level on the subject of treatment and disposal of solid and liquid waste approved in the national legislation for treating sewage sludge produced from urban wastewater treatment plants.
The key characteristic of the Geochemical Method GACS is the usage of geopolymer materials, which have the ability to adapt on the characteristics and particularity of any type of waste. Under this manner, process optimization and performance maximization are achieved.
The combined use of high quality natural materials and few chemical substances in suitable proportions, makes feasible the sludge’s pollutant load to be captured in the mass of the geopolymer materials, resulting in the production of a final product in solid form upon completion of treatment process , which is stabilized and inactivated and which can be disposed of as soil improvers or as an inert material and organochemical fertilizer with addition of appropriate N,P, and K quantities, meeting the requirements of the applicable legislation.
Benefits of the GACS Method, on treatment of urban wastewater against the conventional existing methods can be summarized in the following:
Financial Benefits:
  • Competitive investment cost
  • Significantly reduced operational cost
  • Reduced maintenance cost
  • Reduced operational time

Environmental Benefits:
  • Heavy metals removal even on high concentrations
  • Elimination of pathogen microorganisms
  • Achievement of producing a neutralized sludge which can be used as soil fertilizer
  • Use of natural materials
  • Elimination of odors