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Primary Treatment
Wet weather flow

  • Use BBF (Biological filtration) with special media

  • Primary & wet weather flow treatment simultaneously

  • Remove solids and soluble organics simultaneously

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  • 65-80% smaller footprint than primary clarifiers

  • Repurpose your old primary clarifiers to increase capacity or upgrade your process

  • Up to 50% higher BOD removal than settling

  • Never worry about primary sludge carryover again

  • Zero chemicals, low energy

  • Can be installed underground for unparalleled odor control and unique land repurposing

What makes it possible

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  • Patented new media has the highest solids loading rate of any biofiltration process in the world

  • Gravity-based, zero-energy backwash uses only process water for cleaning

The Jungrang municipal treatment facility is one of the biggest in Seoul. This plant has replaced primary clarifiers in its 66MGD treatment train with underground BBF primary filters, and added 132 MGD in additional BBF biofilters to manage wet weather flow. This plant has already met and exceed its treatment targets for over 6 months at full-scale. 

BBF Typical Primary Clarifier
Capital Cost
• Total Cost ($USD)
• Per Volume ($/m3)
$100 per m3 ($.0.38 per gallon)
$100-120 per m3 ($0.38-0.46 per gallon)
Detention Time 10 min 120 min(1)
Overflow Rate (m3/m2/d) 120m3/m2/d (3,000 gal/ft2) 40(1)m3/m2/d (1,000 gal/ft2)
Footprint (m2/m3d) 0.009 (35%) 0.025 (100%)
TSS Removal 61% 50%
BOD Removal 43% 30%
TP Removal 24% 15%
Sludge Density (%TS) 5% 3%(1)
Energy Use
• Total (kWh/d)
• Cost Average ($USD/d)
Head Loss 2m 0.3m
Chemical Use (AlSO4+Floc)
• Concentration (mg/l influent)
• Cost ($USD/day)

[1] Metcalf & Eddy: Wastewater Engineering, 5th Edition, 2014
[2] WEF Manual of Practice No.32: Energy Conservation in Water and Wastewater Treatment Facilities, 2009

3D Section View of BBF at Jungrang

3D Section View of BBF at Jungrang

Aerial view of the Jungrang BBF retrofit

Aerial view of the Jungrang BBF retrofit

Carbon Diversion Challenges

Primary Treatment Challenge

Finding ways to increase energy savings and energy recovery is a leading trend in the WWT industry. Carbon, originally used in nutrient removal as an electron donor, is now acknowledged as an important energy source. Current primary treatments can effectively remove solid organic but not soluble organic materials. Soluble carbon removal is one of the most critical problems facing advanced biological treatment technologies. 

Wet Weather Flow Challenge

During the wet season, the influent wastewater flow to treatment plants increases significantly. It has been observed that the water quality of influent during the wet season was high in both BOD and Suspended Solids (SS) concentration. The municipal wastewater treatment plants were not able to handle the additional flow conditions and could not help but bypass the wet weather flow, thereby seriously contaminating water body.

Our Solutions (Selected by LIFT Program) 

BBF is a high rate up- flow filtration system that can manage higher levels of BOD and SS during the wet season. Accepted into the general technology scan of the LIFT program based on innovative capacity for carbon diversion, BBF facilitates the effective removal of solids and soluble organics by simultaneously performing biological treatment and physical filtration. This inherent dual functionality enables BBF to be a robust technology platform capable of combining Anammox and/or Algae solutions with wet weather flow treatment.

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