Optimizing Replacement Membranes at the Pompano Beach ......Potential Power Cost Savings (13.5 mgd...
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Optimizing Replacement Membranes at the Pompano Beach Nanofiltration Plant Southeast Florida Utility Council August 14, 2017 Phil Hyer City of Pompano Beach Jason Mraz City of Pompano Beach Frank A. Brinson, P.E. McCafferty Brinson Consulting, LLC
Transcript of Optimizing Replacement Membranes at the Pompano Beach ......Potential Power Cost Savings (13.5 mgd...
Optimizing Replacement Membranes at the Pompano Beach Nanofiltration PlantSoutheast Florida Utility CouncilAugust 14, 2017
Phil HyerCity of Pompano Beach
Jason MrazCity of Pompano Beach
Frank A. Brinson, P.E.McCafferty Brinson Consulting, LLC
Introduction Background Facility Design Design of Pilot Test Unit(s) Goals of Optimization Current Status and Future Plan
Pompano Beach, Florida
Pompano Beach WTP
Water Demands
13.5 mgd ADD
17.4 mgd MDD
Pompano Beach Water Treatment Plant Biscayne Aquifer Raw Water Supply
50 mgd Treatment Capacity
40 mgd Conventional Lime Softening
10 mgd Nanofiltration
Blend NF:LS ~ 40% to 50%
NF Plant Constructed 2003
Existing Membranes Installed 2009
Pompano Beach WTP Process Schematic
Raw Water Quality
Constituent/Parameter Value
Total Hardness 247 mg/L as CaCO3
Total Dissolved Solids 495 mg/L
Color 80 Color Units
Total Organic Carbon (TOC) 20 mg/L
pH 7.2
Iron 1.7 mg/L
TTHMFP 0.40 mg/L
HAA5FP 0.30 mg/L
Blended Finished Water Quality Goals
Constituent/Parameter Value
Total Hardness 50 - 80 mg/L as CaCO3
Color < 6 Color Units
Total Trihalomethanes (TTHM) < 0.064 mg/L
Five Haloacetic Acids (HAA5) < 0.048 mg/L
Specified Permeate Quality and Membrane Performance
Constituent/Parameter Existing Membranes(2009)
ReplacementMembranes(2017-18)
Bicarbonate 25 - 75 mg/L 25 - 75 mg/L
Color < 3 Color Units < 3 Color Units
Total Dissolved Solids < 250 mg/L < 200 mg/L
Total Hardness ? mg/L as CaCO3 Min 25 mg/L as CaCO3
Total Organic Carbon < 1.0 mg/L as C < 1.0 mg/L as C
TTHM Formation Potential < 0.040 mg/L < 0.040 mg/L
HAA5 Formation Potential < 0.030 mg/L < 0.030 mg/L
Maximum TMP 90 psi 73 psi
Design Parameters for NF Process
Design Parameter Units 1 - 5(Two-stage)
Total Permeate Capacity 10.0 mgd
Recovery Rate 85%
Raw Water Feed Flow 11.76 mgd
Number of Units 10 x 2.0 mgd
Array 36:16
Flux Rate 13.7 gfd
Feedwater pH 5.8
Feedwater Antiscalant Dose 1.0 mg/L
4-inch Pilot Test Unit
8-inch Pilot Test Unit
Pompano Beach WTP Process Schematic
8-inch Pilot Test Unit
8-inch Pilot Test Unit
8-inch Pilot Test Unit
8-inch Pilot Test Unit
Objectives of Membrane Optimization Minimize power costs by reducing membrane feed
pressure.
Reduce or eliminate chemical pretreatment while maintaining stable operation
Maintain “reasonable” cleaning frequency (minimum 90 days between cleanings)
Potential Power Cost Savings(13.5 mgd Total ADD, 5.5 mgd Permeate ADD, 6.5 mgd Feed Flow)
Potential Reduction in Feed Pressure = Δ 17 psi
Unit power cost: $0.064/kW-hr
Total Potential Annual Cost Savings: $27,000
Potential Chemical Cost Savings(13.5 mgd Total ADD, 5.5 mgd Permeate ADD)
Acid (145 mg/L at $0.063 per pound): $187,000
Antiscalant (1.0 mg/L at $1.18 per pound): $26,000
Caustic (2.1 mg/L at $0.25 per pound): $5,000
Total Potential Annual Cost Savings: $218,000
Comparison of Cleaning CostsPer-unit Cleaning Chemical Cost: $600
Current Cleaning Frequency: 7 months
Target Maximum Frequency: 3 months
Potential Additional Cleaning Required: 11.4 per year
Potential Additional Cleaning Cost: $6,840 per year
Summary of Potential Cost Savings from Optimization
Potential Annual Power Cost Savings: $27,000
Potential Annual Chemical Cost Savings: $218,000
Potential Additional Cleaning Cost: ($7,000)
Total Potential Annual Cost Savings: $238,000
Pilot Testing Results to Date
Plan Moving Forward Complete pilot testing for
pretreatment chemical optimization with 4-inch pilot unit
Proof/prequalification testing of replacement elements with 8-inch pilot unit (current operating conditions).
Testing of optimized pretreatment protocol with pre-qualified replacement elements.
