1 / 60

Adsorption Technologies

Slides by:Tom Sorg and Darren Lytle U.S. Environmental Protection Agency ORD, NRMRL, WSWRD, TTEB, Cincinnati, Ohio 45268 Contributions by: Yu Jung Chang – HDR Presented at the 2005 Arsenic Training Sessions Sponsored by the USEPA. Adsorption Technologies. Presentation by:

alyssa
Download Presentation

Adsorption Technologies

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. Slides by:Tom Sorg and Darren Lytle U.S. Environmental Protection Agency ORD, NRMRL, WSWRD, TTEB, Cincinnati, Ohio 45268 Contributions by: Yu Jung Chang – HDR Presented at the 2005 Arsenic Training Sessions Sponsored by the USEPA Adsorption Technologies Presentation by: Yu Jung Chang – HDR Engineering, Inc.

  2. Agenda • Adsorption Technology • Application • System Design • System Operation

  3. Agenda • Adsorption Technology • Application • System Design • System Operation

  4. Adsorption Technology As V As V As III As V As V As V As III As V As V As V As III As III As V As V As V As V As III As V Fix Bed Process As V As V As V As V As V As V As V As V As V As V As III As III As V As V As V As V As III As V As V As V As III As V

  5. Accessible Area of Granular Media Diffusion As > 99% of surface for removal is internal Source: M. Edwards, June 2003

  6. Examples of Adsorbent Media Modified activated alumina GFO Bayoxide E33

  7. Agenda • Adsorption Technology • Application—Why/Where? • System Design • System Operation

  8. Application – Why? Number One Reason: Simple to operate!

  9. Application – Why? Other Reasons • Low arsenic in treated water 2-3 ug/L • Reasonable capital and operating cost • Small footprint • Flexibility – use of different media products • Residual disposal usually not a major issue

  10. Application – Where? Low Iron High Iron As MCL Fe SMCL

  11. Application – Where? Low Iron Source Water – Why? High iron sites normally require pre-treatment

  12. Application – Where? Arsenic Demonstration Technologies: Round 1 & 2 Sites

  13. Agenda • Adsorption Technology • Application • System Design • System Operation

  14. System Design • System configuration - parallel vs series • Vessel design – size, materials of construction • Media selection – performance, EBCT, cost • Pre-treatment - oxidation, pH Adjustment • System controls – manual vs automatic • Residual disposal – backwash water, media • Costs – capital and operational

  15. System Design • System configuration - parallel vs series • Vessel design – size, materials of construction • Media selection – performance, EBCT, cost • Pre-treatment – oxidation, pH adjustment • System controls – manual vs automatic • Residual disposal – backwash water, media • Costs – capital and operational

  16. Adsorptive Media System Configuration Roughing filters A A A A Polishing filters B B Series Design Simple Parallel Design

  17. System Configuration Series - Advantages • More conservative – added safety • Maximum use of media – lower operating cost • More flexible change out schedule Series – Disadvantages • Higher capital cost – more tanks • Larger foot print • Higher pressure drop

  18. Arsenic RemovalActivated Alumina System (CS), NH—1998-1999

  19. Adsorptive Media System Configuration After media change out of tanks A A A B B Roughing filters Roughing filters B B A A Polishing filters Polishing filters

  20. Series Design

  21. System Design • System configuration - parallel vs series • Vessel design – size, materials of construction • Media selection – performance, EBCT, cost • Pre-treatment – oxidation • System controls – manual vs automatic • Residual disposal – backwash water, media • Costs – capital and operational

  22. Adsorptive Media Pressure Tank Freeboard Bed expansion 15 -50 % Media EBCT 3 – 10 min Bed depth 3-6 ft

  23. EBCT EBCT—3 to 10 minutes The lower the EBCT • The higher the unit flow rate • The smaller the size of the vessels

  24. Vessel MaterialsPressure and Cost Issues • Fiberglass (FRP) • Carbon Steel • Stainless Steel

  25. FRP Tanks

  26. SS Tanks

  27. System Design • System configuration - parallel vs series • Vessel design – size, materials of construction • Media selection – performance, EBCT, cost • Pre-treatment – oxidation, pH Adjustment • System controls – manual vs automatic • Residual disposal – backwash water, media • Costs – capital and operational

  28. Media Selection Criteria • Performance – water quality dependent • Arsenic form – As III, As V • pH, silica, phosphate, vanadium • EBCT • Cost of media • Regeneration of media vs one time use • Residual Disposal (BW Water and Media) – hazardous vs non- hazardous

  29. Adsorptive Media Listed in NSF/ANSI STD 61

  30. Adsorptive Media Listed in NSF/ANSI STD 61

  31. EPA Pilot Columns Studies Licking Valley High School (LVHS)

  32. LVHS Pilot Plant Tests - As III

  33. LVHS Pilot Plant Tests - As V

  34. System Design • System configuration - parallel vs series • Vessel design – size, materials of construction • Media selection – performance, EBCT, cost • Pre-treatment – oxidation, pH Adjustment • System controls – manual vs automatic • Residual disposal – backwash water, media • Costs – capital and operational

  35. Pre-Treatment Needs • Oxidation of As III to As V • pH Adjustment – pre and post (pH > 8) Acid CO2

  36. Pre-Treatment Needs Oxidation of As III to As V Most adsorptive media have greater removal capacity for As V than As III

  37. Queen Anne’s CountyAdsorptive Media (E33) Treatment System

  38. As III Oxidation Caution! Lose oxidation, arsenic in effluent will likely increase (spike)

  39. Desert SandsAdsorptive Media (E33) Treatment System

  40. Pre-Treatment Needs pH adjustment Removal performance for many media products (AA & iron based media) is pH dependent. The lower the pH, the greater the removal capacity.

  41. pH Adjustment Valley Vista, AZ (44-46 ug/L As) (AAFS 50 media w/acid ) pH 7.8 BVs to 10 ug/L – 8,000 pH 6.8 BVs to 10 ug/L – 25,000

  42. pH Adjustment Arsenic Demonstration Program Bow, NH – Acid/Cauatic 7.5 – 6.5 – 7.8 Rollinsford, NH – CO2 8.2 to 7.2 Valley Vista, AZ – Acid 8.4 to 6.9 Nambe Pueblo, NM – CO2 8.3 to 7.3 Taos, NM – CO2 9.5 - Bunni, TX – CO2 8.0 - Wellman, TX – CO2 8.2 - Tohono O’Odhan – CO2 8.2 -

  43. Valley Vista, AZ – AAFS 50 media pH Adjustment w/acid

  44. pH Adjustment Caution! Lose pH adjustment, arsenic in effluent will likely increase (spike)

  45. System Design • System configuration - parallel vs series • Vessel design – size, materials of construction • Media selection – performance, EBCT, cost • Pre-treatment - oxidation , pH adjustment • System controls – manual vs automatic • Residual disposal – backwash water, media • Costs – capital and operational

  46. System Controls Backwashing of media Manual vs automatic Instrumention – gages, etc (Cost issue!)

More Related