1 / 105

Membrane Filtration

Membrane Filtration. Need Technical Assistance? Call GoToWebinar Support: US & Canada: 1-800-263-6317 International: +1-805-617-7000. If You Need Help. Raise your hand Someone will contact you via chat to help Ask a question at the bottom of your GoToWebinar window. Maximize Your Screen.

Download Presentation

Membrane Filtration

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Membrane Filtration Need Technical Assistance?Call GoToWebinar Support: US & Canada: 1-800-263-6317International: +1-805-617-7000

  2. If You Need Help • Raise your hand • Someone will contact you via chat to help • Ask a question at the bottom of your GoToWebinar window

  3. Maximize Your Screen • For a full screen view hit F5 or full screen icon in bottom right • To return to the regular view, hit F5 again or regular screen icon • You need to be in “regular” view to submit text questions • Hitting Control + H will also give you a larger view

  4. Questions & Answers • You can submit questions/comments anytime during the presentation • Just use the question and answer pane that is located on your screen • Panelists will address as many questions as possible

  5. Polls • Polls will be launched during breaks throughout the presentation • Please be sure to respond to the polls • You will not be able to view the presenter’s screen until the poll is closed by a webinar organizer

  6. Disclaimer The examples included in this presentation are intended for discussion purposes only.  Throughout this presentation, the terms “state” or “states” are used to refer to all types of primacy agencies including U.S. territories, Indian tribes, and EPA Regions. The statutory provisions and EPA regulations described in this document contain legally binding requirements. This presentation is not a regulation itself, nor does it change or substitute for those provisions and regulations. Thus, it does not impose legally binding requirements on EPA, states, or public water systems. This guidance does not confer legal rights or impose legal obligations upon any member of the public. While EPA has made every effort to ensure the accuracy of the discussion in this presentation, the obligations of the regulated community are determined by statutes, regulations, or other legally binding requirements. In the event of a conflict between the discussion in this presentation and any statute or regulation, this presentation would not be controlling.

  7. Webcast Overview • We’ll review the regulatory requirements of the new drinking water regulations as they pertain to membrane filtration: • Introduction • Membrane Filtration Requirements for LT2 and GWR • Challenge Testing • Direct Integrity Testing • Continuous Indirect Integrity Monitoring • Q&A

  8. Today’s Speakers • Michael Finn, Environmental Engineer, Environmental Protection Agency Office of Groundwater and Drinking Water, Drinking Water Protection Branch • Steve Allgeier, Environmental Engineer, Environmental Protection Agency Office of Groundwater and Drinking Water • Brent Alspach, Senior Project Engineer, Malcolm & Pirnie

  9. Poll Question

  10. Membrane Filtration Requirements for LT2 and GWR

  11. Definitions • GWR-Ground Water Rule • LT2ESWTR (abbreviated as LT2) – Long Term 2 Enhanced Surface Water Treatment Rule • Log removal value (LRV) – the reduction in concentration of a pathogen in water, expressed as log10 • Cryptosporidium (abbreviated as Crypto) – a protozoan parasite that can cause acute gastrointestinal illness when ingested Hollow fiber cross-section

  12. LT2ESWTR Elements and Process 0. Systems Subject to LT2 Small systems with low E. coli 1. Initial Round Source Water Monitoring Systems installing max treatment Bin 1 systems 2. Bin Classification 3. Choose Toolbox Option(s) Membrane filtration is one option 4. Implement Tool(s) 5. Second Round Source Water Monitoring (6 years after initial bin classification)

  13. UV Light Pre-sedimentation basin Ozone Chlorine dioxide River bank filtration Slow sand filters Manage timing or level of withdrawal Lower finished water turbidity Membranes Bag and cartridge filters Intake relocation Microbial Toolbox Watershed Control Program Inactivation Demonstration of Performance Improved Treatment Alternative Source Pre-treatment • Options can be used singly or in combination • Systems must meet specific criteria for prescribed treatment credit

  14. Filtered System Bin Classification and Treatment Requirements *Based on annual average concentrations **Applies to plants with conventional treatment; requirements for other treatment types can differ

  15. LT2ESWTR membrane filtration definition • Pressure or vacuum-driven separation process • Engineered barrier that rejects particulate matter larger than 1 µm, primarily by size exclusion • Target organism removal efficiency can be verified by a direct integrity test. • Classes include: • Microfiltration (MF) • Ultrafiltration (UF) • Nanofiltration (NF) • Reverse Osmosis (RO) Cartridge filtration is eligible if it meets the above definition.

  16. LT2ESWTR Basic Requirements for membranes • Process must comply with definition of membrane filtration • Removal efficiency of a membrane filtration process must be established through a product-specific challenge test and direct integrity testing • Membrane filtration system must undergo periodic direct integrity testing and continuous indirect integrity monitoring during operation

  17. LT2ESWTR Testing and Monitoring requirements • Challenge testing: Establishes maximum removal credit for a given filtration device • Direct integrity testing: Routine, direct, and sensitive performance assessment of an operational filtration system • Continuous indirect integrity monitoring: High frequency monitoring of surrogate measures to facilitate rapid response to significant integrity breaches

  18. LT2ESWTR Membrane Testing and Monitoring • Membrane log removal credit based on challenge study or verified through direct integrity testing (whichever is lower) • Minimum requirements for challenge studies • Direct integrity test based on a control limit demonstrating integrity (out of limits =oos and repair) • Continuous indirect integrity monitoring required every 15 minutes (default-continuous turbidity) Cannot exceed 0.15 NTU >15 min

  19. LT2ESWTR and existing membrane facilities • Systems providing 5.5 log Crypto treatment meet LT2-no source monitoring required • Systems in Bin 1 have no additional treatment requirements • Systems in Bins 2-4 • Demonstrate that existing membrane treatment alone meets bin requirement • Demonstrate that existing membrane and other treatment combined meet bin requirement • Use other toolbox options to meet bin requirement

  20. Challenge Testing • A challenge test is an evaluation of the membrane media in its completed form • Demonstrates target organism removal efficiency • One-time, product-specific test • Establishes maximum removal credit • Basic procedure: Spike feed water with target organism or surrogate particle and measure log reduction in concentration. • Log Removal Value (LRV) = log(feed conc.) - log(filtrate conc.)

  21. Challenge Testing • May be conducted on full or small-scale module • Challenge particulates • Target organism (Cryptooocysts,virus) or surrogate particles which are removed no more efficiently than target organism • Must be discretely quantified • Maximum feed conc. = (3.16∙106) x filtrate detection limit (LT2) • Test under maximum design flux

  22. Challenge Testing • Quality Control Release Value (QCRV) calibrated to LRV from challenge test(s) • QCRV measured on all modules not subject to challenge testing • Retest following product modification. • Challenge test results must be reported to the State (LT2) • Old test data may be used if test procedure conformed to current test standards

  23. Direct Integrity Testing • Periodic verification of the performance of an installed, operating membrane filtration system • Test methods are flexible, but must meet requirements for resolution, sensitivity, and frequency. • Pressure-based tests apply pressurized air to membrane • Marker-based tests are similar to a challenge test • DI test used to establish control limit-based on the sensitivity limits of the DI test-within limits membrane meeting removal credit assigned

  24. Direct Integrity Test Methods Considered in the Guidance Manual • Membrane Based Physical Integrity Testing • Pressure decay test • Vacuum decay test • Diffusive flow test • Water displacement test • Concentration Based System Tests • Spiked inert particle test • Molecular marker test • A Manufacturer Developed Test that Satisfies the Criteria Established Under the Rule

  25. Continuous Indirect Integrity Monitoring(LT2 requirements) • Continuous (every 15 minutes) monitoring of some aspect of filtrate water quality that is indicative of removal of particulate matter • Each membrane unit monitored separately • Two consecutive exceedances trigger direct integrity testing • Complements direct integrity testing by providing a real-time indication of membrane integrity, albeit with less sensitivity

  26. Continuous Indirect Integrity Monitoring Methods: • Turbidity monitoring (LT2 default method) • 0.15 NTU control limit • Least sensitive to small integrity breaches • Particle counting and monitoring • Sensitive to small integrity breaches • Conductivity monitoring (RO systems) • Other methods

  27. Other Methods • Must (LT2) be approved by the state • Must (LT2) allow on-line, continuous monitoring • Each membrane unit must (LT2) be monitored • Significant parameter fluctuation should be indicative of an integrity breach • Instrumentation should be sufficiently sensitive to allow a meaningful control limit

  28. GWR Elements • Sanitary Surveys • Triggered (by TCR) source water monitoring • Hydrogeologic Sensitivity Assessment and source water assessment monitoring (State option) • Corrective action • Compliance Monitoring

  29. GWR 4-log virus treatment • 4-log virus treatment (and monitoring*) in lieu of GWR triggered source water monitoring • 4-log virus treatment ( and monitoring*) as a corrective action for ground water source fecal contamination or for significant deficiencies * Compliance monitoring is required to avoid triggered source water monitoring or for treatment as a corrective action

  30. GWR Basic Requirements for membranes used to meet 4-log virus removal • Membranes must have a MWCO or alternate exclusion parameter that reliably achieves 4-log removal of viruses • Membrane operates in compliance with State specified compliance requirements • Membrane integrity is intact

  31. GWR 4-log virus removal: Implementation Issues • Only UF,NF and RO provide a virus barrier • Direct integrity testing is the most accurate method of demonstrating membrane integrity • Direct integrity test pressure may be insufficient to achieve resolution on the scale of virus • Virus size << size of integrity breach detectable by direct integrity test (resolution of the DI test)

  32. GWR 4- log virus removal: Implementation Issues • Continuous indirect integrity monitoring is important-real time indicator of membrane integrity • Indirect integrity monitoring can detect significant membrane failure but may not be sensitive enough to show reduction in virus removal from small defects/damage • Some methods of indirect integrity not present in ground water at levels needed (turbidity, particle counts) • Other parameters may be needed as performance criteria or integrity indicators (e.g.TDS, conductivity, TMP, flux)

  33. GWR 4- log virus treatment: combining technologies • Combinations of technologies-provides multiple virus barriers with a level of redundancy • Membrane with chlorine (low chlorine doses for virus inactivation) • Membrane with UV (lower UV doses can be verified, “off the shelf” equipment)

  34. Summary of Reporting Requirements • Challenge testing: Detailed description of test protocol and results, including calibration of QCRV (LT2) • Direct integrity testing: Monthly report-control limit exceedances (LT2) • Continuous indirect integrity monitoring: Monthly report-any result triggering direct integrity testing (LT2) • GWR Reporting: State discretion

  35. Poll Question

  36. Challenge Testing

  37. Challenge Testing Guidance • Requirements under LT2ESWTR (3.2) • Test organization qualifications (3.3) • Developing a challenge test protocol (3.4) • Module specifications (3.5) • Non-destructive performance testing (3.6) • Selection of modules for challenge testing (3.7) • Small-scale module testing (3.8)

  38. Challenge Testing Guidance, cont. • Target organism and challenge particulate (3.9) • Challenge test solution (3.10) • Challenge test system (3.11) • Sampling (3.12) • Analysis and reporting of results (3.13) • Re-testing modified modules (3.14) • Grandfathering challenge test data (3.15)

  39. Requirements Under LT2ESWTR Performed on a full-scale module or suitable small-scale module Test against Cryptosporidium, a conservative surrogate, or a representative surrogate that can be discretely quantified Challenge concentration less than maximum Test under representative hydraulic conditions Calculate removal efficiency as prescribed Verify LRV of untested modules through non-destructive performance testing (NDPT) Re-test modified membrane products

  40. Test Organization Qualifications No federal regulatory requirements However, challenge testing is intended to be one-time and product-specific Suggested demonstration of qualifications to improve universal acceptance of results Testing by independent, third-party entities, such as NSF, is advantageous but not required

  41. Developing a Test Protocol Guidance on test protocol development, which is not specific to a product or type Membrane module specifications Non Destructive Performance Test (NDPT) Quality Control Release Value Operating conditions Hydraulic configurations Challenge particulates Seeding and sampling

  42. Module Specifications Feed-side membrane area Maximum design flux Maximum feed and trans-membrane pressure Operating constraints (pH, temp, etc.) Direct integrity test parameters NDPT results and QC release value Hydraulic configuration

  43. Deposition Mode System The feed contaminants are captured on the membrane surface and held in place by differential pressure until completely discharged by backwashing (VCF = 1.0)

  44. Suspension Mode The suspended contaminant are concentrated on the feed side, which creates a concern in the event of an integrity breach. (VCF > 1.0)

  45. Volumetric Concentration Factor VCF = 1.0 for systems that operate in deposition Dead-end filtration VCF > 1.0 for systems that operate in suspension Cross-flow filtration (CSTR, PFR) VCF is a function of system recovery VCF is relevant to challenge testing and DIT

  46. Non-destructive Performance Test All membrane modules used for LT2 compliance must meet a quality control release value (QCRV) for a NDPT The QCRV must be consistent with the 3 mm resolution criterion The NDPT should be applied to each module challenge tested to relate the QCRV to the challenge test results Example: bubble-point test

  47. Selecting Modules for Testing No requirement to test a specific # of modules Manufacturer should consider their QCRV in the selection of module for testing If sufficient data is available, it may be prudent to evaluate modules with NDPT at or near the QCRV If not, a random sampling from several manufactured lots may be appropriate Guidance suggests testing at least 5 modules Frequency Test Result

  48. Small-scale Module Testing Provision included to allow flexibility in test design (e.g., testing with Cryptosporidium) Small-scale module must be similar in design and operation to full-scale module All previously discussed challenge test requirements apply to small-scale testing Must establish a QCRV for a NDPT that is applicable to production modules

  49. Test Organism & Challenge Particulate Challenge particulate must be measured and quantified as discrete particles Suitability of a surrogate must be verified Representative surrogates verified by direct comparison with Cryptosporidium Conservative surrogates may be indirectly verified: Size distribution conservative for Crypto (< 1 mm) Dispersed in solution (no clumping or attachment) No significant charge

  50. Potential Surrogates Microbial P. Dimunita S. Marcessans B. Subtillus MS2 (Virus) Inert Particles Latex Spheres Molecular Markers Rhodamine WT FD&C #40

More Related