Pilot Project: Acclimated cultures of freshwater archaea and bacteria degrade synthetic sewage in a salt-water environment


Freshwater is a limited resource in many geographical regions of the Earth. This may be the case in some areas that are very populous of aircrafts and sailing vessels, that require treatment of their wastes. This study was done as a way to investigate methods that may require less usage of the available freshwater in these areas due to wastewater treatment, if 1) archaea and bacteria can survive in the harsh salt-water conditions, 2) if the cultures could degrade cBOD in the salt-water environment, and 3) if the cultures could degrade cBOD in the presence of a popular commercial deodorizer.


ArchaeaSolutions, Inc. (Tyrone, GA) is a company that produces various mixtures of archaea organisms with other microbes to be used in applications for Sludge Management, Biological Dredging, Ammonia and Nutrient Reduction. Archaea is ÔÇťancient bacteriaÔÇŁ and can exist in a syntrophic relationship with bacteria. ArchaeaSolutions, Inc. presented the idea of a pilot study to determine if the Arkea┬« product could successfully degrade wastewater in a saltwater environment before furthering studies to certification. Cromaglass┬« (Williamsport, PA) manufactures sequence batch reactors (SBRs) for wastewater treatment systems. ArchaeaSolutions, Inc. supplied the Arkea┬« and Cromaglass┬« supplied the SBRs used in the pilot study. The Test and Control tanks used in the study were on set cycle consisting of 6 cycles per day with 2 phases per cycle: 2.5 hours of aeration and 1.5 hours of settling per cycle. The Control Tank and Test Tank were kept at equivalent measurements until the Sani-Pack┬« was added to the Test Tank in July for the final test of the study

Methods and Procedure

Synthetic sewage was prepared in the lab with a mixture of chemicals (NH4Cl, C6H12O6, MgSO4 • 7H2O, NaHCO3, Na2CO3, Na2PO4 • 12H2O, CaCl2 • H2O; CH3COOH added to increase cBOD and COD, NaOH added to adjust pH to ~8.2) The COD and pH was tested so that it was comparable to field wastewater sample The 250 gal SBR at Cromaglass┬« was kept at constant volume Field testing at Cromaglass consisted of DO, conductivity, TDS, temperature, pH, alkalinity, and salinity of each both the Test and Control tanks In the CWI lab, testing on the grab samples was done twice weekly: Nitrate-nitrogen, Nitrite-nitrogen, Ammonia-nitrogen, Total phosphorous, Ortho-phosphorous, BOD/cBOD, COD, TSS, MLSS/MLVSS A total of 112 grams of Arkea and 73 pounds of Reef Crystals Sea Salt were added to each tank

Arkea┬« was added in increments until enough had accumulated in the SBRs to degrade the ÔÇťsewage.ÔÇŁ Once stable conditions had been obtained, Reef Crystals Sea Salt was added to the tanks to increase the salinity to that of the ocean (30,000-35,000 mg/L) and the TDS was increased (to 38,100-39,000 mg/L) by the final grab sample. Fixed film media was placed into each tank to maintain active biomass of floc particles of biofilm growth (shown below) 8 g of Miracle-Gro┬« had been added to each reactor (boron, iron, copper, manganese, molybdenum, potassium, zinc, phosphorus, and nitrogen are ingredients of Miracle-Gro┬«). When conditions were reached, 60 mL of Sani-Pak┬« (commercial deodorizer) was added to the Test reactor on July 22, 2013. ATP testing had been obtained four times during the time of the study. TKN testing had also been completed by Seewald Laboratories, Inc.(Williamsport, PA).


Operational Parameter Control Reactor Test Reactor
Dissolved Oxygen(mg/L) 4.3 to 8.1 4.9 to 8.3
pH (standard units) 7.8 to 8.4 7.7 to 8.5
Temperature (˚C) 17 to 24 17 to 24
Total Dissolved Solids (mg/L) 130 to 39,000 180 to 38,100
COD 1,440 1,550

The results determined that the Arkea® was able to successfully degrade synthetic wastewater in a saltwater environment. The initial COD of the raw synthetic sewage ranged from 14,000 ppm-15,000 ppm; COD decreased significantly (by ~90%), after added to tanks containing Arkea.


  • The tests done at CWI as well as the ATP testing done by Process Technology, LLC determined that the Arkea used in the study remained viable (live) in the saltwater environment and with the addition of the Sani-Pak┬« preservative. Additional field testing on larger volume of wastewater to be done.
  • October 6-11, 2013: The pilot study was presented in Barbados at the 22nd annual Caribbean Water & Wastewater Association (CWWA) Conference & Exhibition.

Works Cited

  • Gerardi. Michael H., Acclimated cultures of freshwater archaea and bacteria degrade synthetic sewage in a salt-water environment. (Oct. 2013)

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