Water Fit for Use. Avoiding the Unintended Consequences of Good Intentions

Transcription

1 Water Fit for Use Avoiding the Unintended Consequences of Good Intentions Ronald Tebbetts Industrial Technical Consultant, Global (225)

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3 Water Flow Diagram Steam Loss Venting Cooling/Scrubber Evaporation Purchased Water Rain Surface Water Plant Processes Water in Product Well Water in Crude WWT Direct Discharge

4 So what is the usual response? Purchased Water Surface Water Plant Processes Well Improve the supply Find a new source Drill a well Install another pump Municipal Waste Water» El Paso Reclaim Water» Title 22 Water in California

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6 Water Conservation Efforts High Recycle Cost Reuse Reduce Low Low Effort/Risk High

7 Where is the Water being used?

8 Step One: Reduce your use aka: The Low Hanging Fruit Increase Cycles Cooling and Steam Systems Stop uncontrolled blowdown Reduce tower drift Regulate or automate the blowdown Stabilize make-up preparation Make sure the tower is running efficiently

9 Improve Cycles of Concentration 700 Impact of Cycles : Water Savings Blowdown (GPM) Cycles of Concentration Blowdown flow based on 50,000 gpm recirculation rate and 15 o F Delta T

10 Improve Cycles of Concentration Impact of Cycles : Water Savings vs. Risk Blowdown (GPM) CaCO3 SI Cycles of Concentration 0 Blowdown flow based on 50,000 gpm recirculation rate and 15 o F Delta T

11 Reduce your use Optimize Filter/Ion Exchange Processes Condensate Recovery Fix steam leaks Steam Trap maintenance Vent Condensers

12 Reduce your use Consider Dry Cooling or hybrid towers (Adiabatic Towers)

13 Step Two: Reuse what you have. Hydraulic Model

14 If water were pure, we could use it over and over and over.

15 The Problem Ions Scaling Ions Calcium Magnesium Silica Deposition Concerns Iron Manganese Aluminum Corrosive Ions Sulfates Chlorides Alkalinity (HCO3, CO3)

16 So Optimizing Water Use is a Salt inventory management challenge

17 AND Chemistry is the primary driver

18 You need an Ionic Model

19 Reuse what you got Filter/Demineralizer Backwash Usually Clarified Raw Water Will contain some turbidity Collect Condensates being sewered SWS or OH Water for Desalter Wash Water May contain hydrocarbons/ammonia that could affect Desalter performance

20 Problems with Reuse Usable water in wrong place Individual sources too dispersed and small No storage capacity May contain ions and other contaminants that are not compatible with receiving process.

21 Step Three: Recycle Waste Streams Steam Loss Venting Cooling/Scrubber Evaporation Purchased Water Rain Surface Water Plant Processes Water in Product Well Water in Crude WWT Direct Discharge

22 Cold Lime Softening RO Treatment Ultrafiltration Thermal Desalination Plume abatement Recycle Equipment (SPX Air2Air Water Recovery System)

23 Zero Liquid Discharge Falling Film Evap with Crystallizer Cold Lime Softener

24 Words of Caution Recycling concentrates the waste Understand mineral solubility Understand effects of corrosive ions Understand how it will affect system equilibrium

25 Words of Caution Know the WWT Permit Requirements - May have minimum flow requirements - Waste may become toxic Lower flow Higher Dissolved Solids loading - May reduce the food supply to WWT

26 Get Your Water Treatment Professional Involved Early in the Process

27 Thank you!