After a SeHAWK® pilot study demonstrated effective treatment of FGD blowdown for selenium, nitrate, arsenic, and mercury removal, a 2800 MW southern power utility chose to install a full-scale SeHAWK® FGD bioreactor at the facility. The system was commissioned in 2019, with Frontier Water Systems personnel providing thorough onsite engineering presence to ensure the successful mechanical, electrical, and operational success of the bioreactor installation. Within two weeks of startup, the SeHAWK® FGD bioreactor demonstrated treatment performance to well below ELG standards.
SeHAWK®FGD Blowdown 2×300 gpm Treatment Plant
SeHAWK® FGD 550 gpm Treatment Plant
An eastern power utility, and prior owner of a competing biological metals removal system, switched to the SeHAWK® FGD bioreactor for selenium, mercury, nitrate, and arsenic ELG compliance. The second of three plants for the utility, the SeHAWK® FGD installation is located at a 2000 MW eastern power plant and is designed for a flow range of 150-550 gpm. Since commissioning in 2018, the SeHAWK® has been online to deliver consistent compliance with ELG standards.
SeHAWK® 300 gpm FGD Treatment Plant
An eastern power utility, and prior owner of a competing biological metals removal system, switched to the EPA recommended SeHAWK® FGD bioreactor for selenium, mercury, and nitrate ELG compliance. As the first of three SeHAWK® installations for this client, is plant is located at a 2400 MW southeastern power plant. The installation is designed for a flow range of 100-300 gpm. The equipment was designed, built, and delivered to site 14 months after ordering, demonstrating the efficacy and benefit of Frontier Water System’s prefabricated approach.
SeHAWK® Pilot Demonstration of Shutdown Performance
A southern power utility evaluated a SeHAWK® bioreactor for selenium, nitrate, arsenic, and mercury removal of FGD blowdown water through a long-term pilot trial. This pilot trial included Frontier-provided iron co-precipitation pretreatment.
The pilot demonstrated sustained, long-term, compliance with 2019 ELG standards. Additionally, the pilot underwent two, extended 5-week shutdowns to explore the effects on system performance, demonstrating effective recovery from each of these shutdowns.
SeHAWK® Pilot Demonstration of FGD Blowdown with high TDS and Chlorides
In 2016, a SeHAWK® pilot bioreactor was installed and operated at an Eastern Power Utility. The pilot system explored treatment of selenium, mercury, and other constituents in high TDS water. The pilot successfully removed selenium below ELG limits for the duration of the study with influent TDS concentrations reaching a maximum level of 38,000 parts per million. The pilot was operated with limited pretreatment and at a lower EBCT than a full-scale system which further demonstrates the capability of biological treatment and opens the door for the possibility of reduced capital expenditure in full-scale designs.
SeHAWK® Pilot Demonstration of Scalability
Three pilot demonstration units were installed at separate facilities for an eastern power utility. The objective was to explore the efficacy of the SeHAWK® two stage biological treatment system compared to other available technology. The results showed efficient and effective performance which resulted in the purchase of three full-scale systems; plant 1 and plant 2 successfully completed commissioning in early 2019. The full-scale results represent a strong performance link between full-scale and pilot systems.
SeHAWK® Pilot Demonstration of FGD Blowdown with Variable Pretreatment and High Influent Temperature
A pilot demonstration was installed at a state-run energy facility with feed from a single pass FGD system. Upon startup, the system explored the maximum biological operating temperature of 105°F.
The system experimented with a wide range of pretreatment operational conditions to demonstrate the hardiness of the biological approach. The pilot produced results compliant with the EPA ELGs, despite varying influent conditions. The ultrafiltration unit demonstrated effective selenium polishing ability during this pilot as well, with a maximum additional removal up to 30 parts per billion.
SeHAWK® 50 gpm FGD Demonstration Scale Treatment Plant
After several SeHAWK® pilot studies showed successful treatment of FGD blowdown for selenium, nitrate, arsenic, and mercury removal, a southern power utility chose to install a demonstration scale SeHAWK® FGD bioreactor at one of their plants in the South Eastern US. The installation was completed in 2016, demonstrating FGD metals compliance below ELG limits. The system was restarted in October 2019 and continues to operate as a demonstration and R&D unit for the client.