Deborah Helstrom, P.E.

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217.157 Membrane Bioreactors Treatment Systems
(MBR)

• Deborah Helstrom, P.E.
• Utilities Technical Review
• Water Supply Division
• 512-239-6705
• dhelstro_at_tceq.state.tx.us

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217.157 Membrane Bioreactors Treatment Systems
(MBR)

• Information used to draft
• What it contains
• How to use the rule

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Membrane Bioreactors (MBR)

• Compiled Surveys from Vendors of Membranes
• Huber, Koch, Kruger, Kubota, Siemens, Zenon
• Results of Survey, Literature and Other State
  Regulations
• Concerns
• Prevention of Fouling
• Adequate aeration at high MLSS concentrations
• Achievable rate of flow through membranes
• Adequate pretreatment i.e. fine screening
• Hydraulics
• Ensure Integrity
• Foam Control
• Warranty
• Nutrient Removal

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Membrane Bioreactors (MBR)

• Applicability
• Submerged
• Low-pressure, vacuum or gravity
• Ultrafiltration or microfiltration
• 217.8(b)(2) Approval of Nonconforming and
  Innovative Technologies
• May require pilot study and/or 2 year performance
  bond

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Membrane Bioreactors (MBR)
Expected Performance

• CBOD5 5 mg/l
• TSS 1 mg/l
• Ammonia 1 mg/l
• Total Nitrogen (w/pre-anoxic zone) 10 mg/l
• Total Nitrogen (w/pre-anoxic and
• post-anoxic zone) 3 mg/l
• Total Phosphorus (with chemical addition)
• 0.2 mg/l
• Total Phosphorus (with Bio-P removal)
• 0.5 mg/l
• Turbidity 0.2 NTU
• Bacteria up to 6 log removal (99.9999)
• Viruses up to 3 log removal (99.9999)
• If proposed design is for higher quality
  effluent,
• Pilot Study or Data from Similar Facility

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Membrane Bioreactors (MBR)

• Membranes
• Hollow fiber or Flat plate
• Nominal Pore Size
• Microfiltration 0.10 0.40 microns
• Ultrafiltration 0.02 to 0.10 microns
• Common Membrane materials
• Pretreatment
• Fine Screen - perforated plate or drum
• Hollow fiber 1.0 - 2.0 mm
• Flat plate 2.0 - 3.0 mm
• No Bypass
• Primary clarifier Evaluated for gt 1 MGD
• Grit Removal excessive I/I
• Oil and Grease Removal 50 mg/l

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Membrane Bioreactors (MBR)

• Operation
• Average Daily Net flux rate _at_ 20 C 12
  to 20 gfd
• Peak Daily Net flux rate _at_ 20 C
  20 gfd
• Two Hour Peak Daily Net flux rate _at_ 20 C 24
  gfd
• Operational Range for TMP
• Maximum Operational TMP
• Hollow Fiber 2.0 10.0 psi Max
  12.0 psi
• Flat Plate 0.3 - 1.5 psi Max
  3.0 psi
• Operational Range of MLSS Concentration
• Bio Reactor 4,000 - 10,000 mg/l
• Membrane Tank 4,000 12,000 mg/l
• Operational control parameters
• SRT 10 25 days

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Membrane Bioreactors (MBR)

• Operation
• Amount of air used per square foot of membrane
• 0.01 0.04 SCFM / SF
• Method of Integrity Testing In-line Turbidity
  lt1.0 NTU
• Hollow Fiber Pressure Decay Testing
• Surface Wasting to Foam Control
• Run in full manual mode or backup PLC
• Aeration
• alpha value of 0.5 or lower
• anoxic 0.5 mg/l DO
• aerobic 1.5 3.0 mg/l DO
• membrane 2.0 - 8.0 mg/l DO
• Nutrient Removal
• deoxygenate recycle
• recycle 300 600 percent

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Membrane Bioreactors (MBR)

• Redundancy
• N1, trains, units or storage. Show calculations
• Peak Flow
• Peak Ratio of 2.5 requires Equalization,
  off-line storage or reserve membrane capacity
• RAS rate
• 200 400 percent of influent
• Warranty
• 5 year on Membranes
• May require a 2 year performance bond

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217.157 Membrane Bioreactors Treatment Systems
(MBR)

• Engineering Report Required
• Common range of values
• Justification for using parameters outside the
  common range
• May be required to provide 2 year performance
  bond

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Membrane Bioreactors References

• So, You Decided to Build an MBR? Tips to help
  optimize process performance, Merlo, Rion et al,
  WET, www.wef.org/magazine November 2006.
• State of Washington, Department of Ecology,
  Orange Book, Sewage Treatment Design Criteria
• Water Environment Federation, Membrane Systems
  for Wastewater Treatment, 2006
• Manufacturers
• Huber, Koch, Kruger, Kubota, Siemens, Zenon