Phys/Chem Optimization


Optimization of chemical usage for primary (Phys Chem) treatment

Liberty Hydro’s laboratory is fully equipped to provide FGD treatment optimization.

  1. Our technical professionals will evaluate Flue Gas Desulfurization (FGD) purge water to determine the constituents in the water and the effects of various operating condition on the resultant water quality over the course of a year.
  2. Our Goal: determine the best “physical chemical” (phys/chem) treatment to remove the bulk of contamination from FGD purge water. The first step requires raising the pH by adding caustic soda or other lime softening solution, which will cause certain dissolved metals to precipitate from solution. This step is followed by adding certain coagulants and polymers, to enhance precipitation. The final steps are clarification and filtration. This is the basic means to remove the bulk of contaminants. Additional treatment, secondary and tertiary, can be added to remove specific targeted contaminants, like selenium, mercury and arsenic.
  3. Liberty Hydro will test various pretreatment chemicals (including organosulfides from various suppliers) designed to provide the best solution for each specific type of FGD purge water. We will supply a fully detailed report on each step of the phys/chem process and provide a specific treatment train recommendation, designed to meet the upcoming Effluent Limitation Guidelines.
  4. Liberty Hydro will collect FGD purge water in totes and provide off-site evaluation for phys/chem optimization. Testing can be done throughout the year to assess seasonal and operational variations. No need to run a pilot unit on site at this stage.
  5. Each generating facility will benefit from a customized analysis of its FGD purge water and the establishment of an optimized phys /chem treatment protocol, so that the phys / chem system can be properly designed and operated prior to testing and installing downstream treatment technologies. This will save the generating facility time and money eliminating the need for costly trial and error evaluations onsite.
  6. When a facility is ready to evaluate final compliance, Liberty Hydro can install an intermediate-sized pilot unit using Liberty Hydro’s ZVI Blue™ technology. This technology, when preceded by an optimized phys/chem system, has been proven in field trials at several major power generating facilities for removing selenium, mercury and arsenic.