Strategies for Removing Solids and Oil from Water Oil from Water Steel Industry Water Conference b September 12‐14, 2012 Clearwater Beach, FL
ChemTreat’s Steel Industry Water Conference 9‐12 to 9‐14‐2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission
Tom Hennessy
How much does it cost to deal How much does it cost to deal with an oil spill? • If you lose 100 gallons of oil into your water circuit how much does it cost to deal with circuit, how much does it cost to deal with it? – Remove it? R it? – Dispose of it? – Clean up after it? Cl f i? – Deal with oil coated process? ChemTreat’s Steel Industry Water Conference 9‐12 to 9‐14‐2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission
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F Forms of Oil f Oil • Free Oil • Emulsified Oil • Oil Coated Solids • Soluble (Glycol) ChemTreat’s Steel Industry Water Conference 9‐12 to 9‐14‐2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission
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ChemTreat’s Steel Industry Water Conference 9‐12 to 9‐14‐2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission
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“Free Oil” Skimmers “Free Oil” Skimmers • Rope and Mop Skimmers • Floating Drum or Disk Filters • “Beach” Beach Skimmers Skimmers • Fixed Weir Skimmers
ChemTreat’s Steel Industry Water Conference 9‐12 to 9‐14‐2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission
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ChemTreat’s Steel Industry Water Conference 9‐12 to 9‐14‐2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission
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API Oil Separator ChemTreat’s Steel Industry Water Conference 9‐12 to 9‐14‐2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission
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Solids ‐ Mill Scale Solids Mill Scale • Approximately Approximately 1% of production becomes 1% of production becomes mill scale (caster and rolling combined) • Mill Mill scale particles vary in size; > 50% less l i l i i 50% l than 10 microns • Mill scale isn’t just iron oxide; oil and grease, and biological solids can be part of it
ChemTreat’s Steel Industry Water Conference 9‐12 to 9‐14‐2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission
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Removing Oil and Solids Removing Oil and Solids The desired water quality may require: The desired water quality may require: Settling and removal of coarse scale Flotation and removal of oil and grease Filtration Filtration of fines and emulsified oil and of fines and emulsified oil and grease
ChemTreat’s Steel Industry Water Conference 9‐12 to 9‐14‐2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission
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Sedimentation Basin di i i • Removes readily settleable or floatable solids by sedimentation • Provides quiescent flow and retention time to allow solids to separate • Settled solids and floated oil are mechanically removed.
ChemTreat’s Steel Industry Water Conference 9‐12 to 9‐14‐2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission
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Scale Pit or Settling Basin Scale Pit or Settling Basin Floating oil and grease
Heavy sludge settles to bottom if horizontal flow is slow enough to allow contact with bottom. This is the sludge collection zone ChemTreat’s Steel Industry Water Conference 9‐12 to 9‐14‐2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission
Overflow O fl weir
Pump well
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Clarifier and Thickener Influent
Overflow
Underflow Heavy sludge settles to bottom if horizontal flow is slow enough to allow contact with bottom. This is the sludge Collection zone Collection zone ChemTreat’s Steel Industry Water Conference 9‐12 to 9‐14‐2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission
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Pressure Sand Filters Pressure Sand Filters
ChemTreat’s Steel Industry Water Conference 9‐12 to 9‐14‐2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission
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Moving Bed Filter
ChemTreat’s Steel Industry Water Conference 9‐12 to 9‐14‐2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission
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Making it Work Making it Work • System Clean Up – When When the system is very dirty it can the system is very dirty it can require strong measures to clean up
• Maintenance Dosing i i – Once cleaned up, maintaining a clean system is essential
ChemTreat’s Steel Industry Water Conference 9‐12 to 9‐14‐2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission
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Cooling
Hot Strip Mill Interceptor Flush Water
Sand Filter
Blow Down
Sand Filter
Scale Pit Scale Pit
Back Wash
To Waste Plant – Clarifier and Filter Press
Oil ChemTreat’s Steel Industry Water Conference 9‐12 to 9‐14‐2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission
Scale
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Hot Strip Mill Scale Pit Effluent Selection of Filter Aid
Raw
Filtered
2.5 mg/L
5 mg/L
ChemTreat’s Steel Industry Water Conference 9‐12 to 9‐14‐2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission
10 mg/L
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Hot Strip Mill Scale Pit Hot Strip Mill Scale Pit
Before After ChemTreat’s Steel Industry Water Conference 9‐12 to 9‐14‐2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission
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Scale Pit Oil Skimmer
ChemTreat’s Steel Industry Water Conference 9‐12 to 9‐14‐2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission
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Scale Pit Oil Skimmer
ChemTreat’s Steel Industry Water Conference 9‐12 to 9‐14‐2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission
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Cooling
Hot Strip Mill Interceptor Flush Water
Sand Filter
Blow Down
Sand Filter
Oil
Scale Pit Scale Pit
Back Wash
To Waste Plant – Clarifier and Filter Press
Emulsion Breaker
Scale Filter Aid ChemTreat’s Steel Industry Water Conference 9‐12 to 9‐14‐2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission
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Clean Mill Scale
ChemTreat’s Steel Industry Water Conference 9‐12 to 9‐14‐2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission
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Removing Oil and Grease Removing Oil and Grease 1. Remove oil and solids as soon as possible – Once you get it out, keep it out. Don’t re‐ contaminate the system
2. Keep suspended solids low p p – Suspended solids absorb oil and make it harder to separate harder to separate – It is easier to break oil out of clean water
ChemTreat’s Steel Industry Water Conference 9‐12 to 9‐14‐2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission
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S Separation Requires: ti R i
Mixing to thoroughly disperse chemicals and initiate floc formation
Particle Contact to promote floc size and capture fines capture fines
Time to separate floc from water
ChemTreat’s Steel Industry Water Conference 9‐12 to 9‐14‐2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission
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Cooling
Sand Filter
Rolling Mill
Sand Filter Scale Pit
12,000 GPM
Rope Skimmer
Scale Roll Off
ChemTreat’s Steel Industry Water Conference 9‐12 to 9‐14‐2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission
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Roll Off
Before Dewatering Aid B f D t i Aid ChemTreat’s Steel Industry Water Conference 9‐12 to 9‐14‐2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission
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