Risk Management Through Water Efficiency Auditing A. Todd Lusk, PE - PowerPoint PPT Presentation

Environmental Federation of Oklahoma October 30, 2014 Risk Management Through Water Efficiency Auditing A. Todd Lusk, PE ENVIRON International Corporation Florence, KY

Presentation Topics • You Cannot Manage What You Cannot Measure – Understanding Water Quality and Quantity • Beyond the Four Rs – Elements of a Comprehensive Water Audit • What Counts Can’t Always Be Counted – Priorities and Secondary Impacts for Water Reduction Opportunities • Questions and Answers 2

Integrated Water Management 1.0 Grey Water Risk Mapping 0.8 Blue Water 0.6 Grey Water Blue Water 0.4 Green Water Green 0.2 Water 0.0 Baseline Residual Footprinting Efficient Use Watershed Management 3

Water Risk Drivers • Economic (Pricing) • Community “License to Operate” • Physical Scarcity (or Competing Interests) • Brand Reputation (w Customer & Consumer) • Corporate Reporting of Material Risks • Regulatory Constraints 4

Recognizing and Determining “Quality” • General chemistry – pH – Conductivity/TDS/Salt – TSS • Process-specific chemistry – Organics – Metals • Parameters for recycle technologies – Cations/anions – Scaling potential – Silt Density Index 5

The “Four Rs” and Beyond Treated Water Wastewater Wastewater Manufacturing Source Discharge Treatment REUSE REDUCE Reuse Wastewater Manufacturing Treatment Treatment RECYCLE REPLENISH 6

Expanding Water Stewardship Life Cycle (Supply Chain + Producer + Consumer) Watershed Community Plant 7

The Water (Audit) Cycle Water Efficiency Water Risk “Reasonable Benchmarking & Assessments Reduction Strategy Reductions” in Use Baseline Footprint 1.0 Grey Water 0.8 Blue Water 0.6 0.4 Green Water 0.2 0.0 Baseline 1.0 Grey Water 0.8 Blue Water 0.6 Grey Water 0.4 Blue Water Green Water 0.2 Green Water Minimize Impact “Reasonable 0.0 Baseline Residual Residual Footprint and/or Offset Investments” Residual Footprint 8

Pre-Audit Investigations • Data, data, data – Balance known water intakes, uses, and outputs – Chronological trending – Usage and costs (current + projected) 9

Comprehensive Audit • Project Components – Review Facility Operations and Water & Salt Balances – Identify Opportunities for Flow/Cost Reduction – Rank Opportunities Based on Expected Payback Period • Target Opportunities – Cooling/Utility Water Sources – Water Monitoring & Minimization – “Clean/Dirty” Stream Segregation – Steam/Condensate Management – Treatment/Reuse • Holistic Evaluation – Water Savings vs. Economic/Multimedia Impacts – Flow Reduction vs. Effluent Quality 10

Simple Questions • Where is this stream coming from? • Where it this stream going? • What is the water quality of the stream? – Do I have enough data to determine quality? • Can I measure or estimate flow on this stream? – Does it vary? If so, why? • What else can I do here? – Apply the 4 Rs – Compare quality to other streams 11

Ranking Reduction Opportunities • Projects ranked on five criteria: 1. Capital Rating (implementation cost) 2. Savings Rating (flow/cost) 3. Technical Feasibility Rating (% chance of successful implementation) 4. Implementation Difficulty Rating (level of analysis, engineering, and plant impact) 5. Timeframe Rating (project duration) • Overall Rating = product of Ratings 1-4 – Rating 5 typically dependent on others, thus considered separately 12

Ranking Reduction Opportunities Water % of 2013 Implementation Net Savings Usage Cost Savings Overall Payback Rating (kgal/yr) (%) ($) ($/yr) (yrs) Opportunity 13

Reduction Opportunities - Behavioral Category Examples of Water Reduction Housekeeping § Reducing wash down flow, volume or frequency (e.g., high-pressure hoses, flow restrictors, dry cleanup procedures) Maintenance § Leak inspection and repair § Maintenance of flow measurement devices § Maintenance of flow delivery devices (shower heads, spray nozzles, hoses) Training § Develop tools to identify critical flow balance items § Establish employee awareness of reduction plans § Solicit employee suggestions/participation § Train the trainer approach § Standardized toolkit 14

Reduction Opportunities - Process Category Examples of Water Reduction Metering § Install meters and recorders at key flow locations (intakes, outfalls, major consumers) § Develop estimating tools for unmeasured flows (e.g., cooling tower evaporation, product loss) § Maintain flow balance as operational tool Quality § Establish quality criteria for indirect uses (e.g., cooling towers) Constraints § Reduce intake/blowdown rates to minimize fresh water usage in above processes (i.e., longer cycle times) § Introduce water treatment chemicals to improve cycle time § Set pump cooling/flushing water to minimum requirement per manufacturer recommendations Process Controls § Review process control variables to identify less flow-intensive controls (e.g., pH or conductivity instead of time, timer instead of operator visual check) § Determine if changes to production scheduling could impact water balance § Automatic controls (e.g. solenoids) on product washing and conveyors to stop flow when production halts 15

Reduction Opportunities - Facility Upgrades Category Examples of Water Reduction Low-flow and No- § Replace water-based product cleaning with air systems flow Processes § Replace water-based lubrication systems with dry lube (e.g., silicon-based) systems Water Reuse § Return “clean” streams into makeup for “less clean” streams with less stringent quality criteria Water Treatment § Plant-wide or process-specific water treatment (ultrafiltration and/or reverse osmosis) for recycle § Recovery and treatment of inflow reject streams (e.g., RO reject, filter backwashes) for in-plant use § Minimize backwash water volumes (proper chemical dosing, backwash on ∆ P rather than schedule) 16

17 Increasing Water Reduction (Linear) Cost-Benefit Analysis Increasing Cost (Logarithmic)

Indirect Benefits • Facility Production – Increased throughput, lower unit cost • Public Perception – Local, regional, national • Knowledge Transfer – Audit findings at one site applicable to others 18

Trading Quantity for Quality • Water reduction inherently impacts effluent quality – Residual organics (BOD, TOC) – TDS (salt) Increased Recycle – Heavy metals Effluent Quality – Suspended solids – Temperature • Additional treatment or pretreatment may be needed • Quality changes may impact existing treatment – Chemical usage – Biological treatment toxicity – Whole effluent toxicity 19

In-Plant Impacts of Water Reduction • Higher concentrations of acidity/ alkalinity – Corrosion – Scaling • Higher concentrations of salt/ TDS/chloride – Corrosion • May require additional pretreatment steps – Neutralization – Softening • May require MOC changes – HDPE/PVC vs. Cu/steel 20

Trans-Media Impacts Hg SO x NO x CO 2 Concept Water Recycle/Reuse Power Project Solid Waste Coal 21

A “Water-Energy Nexus” Increasing Energy Demand 22

Closing Thought “ When the well is dry, we know the worth of water. ” Benjamin Franklin, Poor Richard’s Almanac 23