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Download PDF File Bull Run Filtration Pilot Study Report Pilot Study November 2020 Prepared by Final Pilot Study Report Prepared for November 202 0 This page intentionally left blank. Final Pilot Study Report Contents List of Figures ...................................................................................................................................................... v List of Tables ...................................................................................................................................................... xi List of Abbreviations ........................................................................................................................................ xiv Acknowledgements ............................................................................................. Error! Bookmark not defined. Executive Summary ......................................................................................................................................... xix 1.0 Introduction ...........................................................................................................................................1-1 1.1 Background ............................................................................................................................ 1-1 1.2 Pilot Plant Study Objectives ................................................................................................... 1-2 1.3 Test Conditions Summary ...................................................................................................... 1-2 1.4 Water Treatment Goals ......................................................................................................... 1-5 2.0 Pilot Plant Configuration ........................................................................................................................2-1 2.1 Flocculation and Sedimentation ............................................................................................ 2-3 2.2 Ozonation Pilot Module ......................................................................................................... 2-4 2.3 Filtration Pilot Module ........................................................................................................... 2-5 2.3.1 Filter Media Configurations ...................................................................................... 2-6 2.3.2 Filter Media Backwash Setpoints ............................................................................ 2-10 2.4 Solids Handling ..................................................................................................................... 2-12 2.5 Varying Operational Parameters ......................................................................................... 2-13 2.6 Water Quality Data Collection ............................................................................................. 2-14 2.6.1 Comprehensive Water Quality Testing (or Measurement) .................................... 2-14 2.6.2 Sampling Locations ................................................................................................. 2-16 2.6.3 Online Instrumentation and Zeta Potential ............................................................ 2-16 2.7 Discharge Compliance and Mitigation of Risk to Aquatic Life ............................................. 2-18 3.0 Raw Water Quality Characteristics ........................................................................................................3-1 3.1 Monthly and Seasonal Overview ........................................................................................... 3-1 3.2 Temperature, Alkalinity, and pH ............................................................................................ 3-4 3.3 Raw Water Turbidity .............................................................................................................. 3-6 3.4 Particle Counts ....................................................................................................................... 3-7 3.5 Algae .................................................................................................................................... 3-11 3.6 Organics ............................................................................................................................... 3-13 3.7 Metals and Inorganics .......................................................................................................... 3-14 3.8 Summary .............................................................................................................................. 3-15 4.0 Approach to Data Analysis and Quality Control ....................................................................................4-1 4.1 Data Quality Control .............................................................................................................. 4-1 4.1.1 Training ..................................................................................................................... 4-1 4.1.2 Documentation ......................................................................................................... 4-1 4.1.3 Online Instrumentation ............................................................................................ 4-1 Portland Water Bureau i Brown and Caldwell Final Pilot Study Report 4.1.4 Water Quality Bench Instruments ............................................................................ 4-2 4.1.5 Portland Water Bureau Lab Analysis ........................................................................ 4-3 4.1.6 Eurofins Contract Lab Analysis .................................................................................. 4-3 4.2 Data Analytics ........................................................................................................................ 4-4 4.2.1 Filter Run Time and UFRVs ........................................................................................ 4-4 4.2.2 Turbidity .................................................................................................................... 4-7 4.2.3 Head loss ................................................................................................................... 4-8 4.2.4 Particle Counts .......................................................................................................... 4-8 4.2.5 Organics Removal ................................................................................................... 4-10 4.3 Data Presentation ................................................................................................................ 4-10 5.0 Coagulation, Flocculation, and Sedimentation ......................................................................................5-1 5.1 Coagulation Testing and Selection ......................................................................................... 5-1 5.1.1 Bench-scale Jar Testing ............................................................................................. 5-1 5.1.2 Pilot Coagulation Selection–Summer/Fall ................................................................ 5-3 5.2 Coagulation .......................................................................................................................... 5-27 5.2.1 Summary of Pilot Coagulant Comparison ............................................................... 5-27 5.2.2 Evaluating Effectiveness–Zeta Potential and SCM .................................................. 5-28 5.3 Flocculation .......................................................................................................................... 5-30 5.4 Coagulant Aid ....................................................................................................................... 5-31 5.5 Sedimentation ...................................................................................................................... 5-35 5.6 Direct Filtration Testing ....................................................................................................... 5-37 5.7 Turbidity Spiking Study ........................................................................................................ 5-44 5.7.1 Influent Water Quality ............................................................................................ 5-44 5.7.2 Coagulation, Flocculation, and Sedimentation ....................................................... 5-48 5.7.3 Settled Water Quality ............................................................................................. 5-49 5.8 Solids Handling Considerations ............................................................................................ 5-52 5.9 Coagulation, Flocculation, and Sedimentation Summary .................................................... 5-55 6.0 Oxidation ................................................................................................................................................6-1 6.1 Ozone Kinetics ........................................................................................................................ 6-1 6.1.1 Bench-scale Testing ................................................................................................... 6-1 6.1.2 Pilot-scale Ozone Demand and Decay ...................................................................... 6-2 6.2 Chlorine Kinetics .................................................................................................................... 6-9 6.2.1 Pilot-scale Chlorine Demand and Decay ..................................................................
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