Contact-Water-Filtration-Severn-Trent

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Contact Water Filtration Presented to:

Steel Making Water Conference CLEARWATER, FLORIDA Prepared by:

Mr. Charles J. Guzelli Industrial Sales Manager

13 September 2012

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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CHARLES J. GUZELLI Industrial Sales Manager  Career - With Dravo / Tetra / Severn Trent - 30 years  Dravo Corporation - Machine Shop Production Manager  Blaw Knox Mill Machinery - Class A Estimator  Wean United Engineering - Chief Estimator  Dravo Corporation - Proposal Engineer  Tetra Technologies - STS      

1988 to 1993 - Chief Estimator 1993 to 1994 - Field Service Manager 1994 to 1997 - Senior Project Manager 1995 - Construction Manager g 1997 to 1999 - Proposal Manager 1999 to - Industrial Sales Manager

 Education - RMC / Business: PITT / Mechanical Eng’r 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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METHODS OF TREATMENT Various treatment processes in US Steel market - Once pass through systems with no treatment - Sedimentation Basins and Dragout Conveyors - Mixed bed and multi-media Filtration Systems - Horizontal Clarifiers and Settling Basins - Ponds and Lagoons - 1959 DRAVO introduces Mono-media Filter to USA - 1962 DRAVO begins to install Filters in Refineries - 1965 DRAVO begins to install Filters in Steel Mills - 1968 Clean Cl AIR actt passed d by b US G Governmentt - 1972 Clean WATER act passed by US Government - Continuous Backwash Filters and EMF Filters - Future ????? 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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FILTRATION BENEFITS Filters help Steel Producers achieve: Higher Steel Production through more usable water - Improving Mill Efficiency through even cooling - Improving Impro ing Prod Product ct Q Quality alit - Reducing Maintenance

MORE WATER = MORE STEEL - No strainer - spray nozzle plugging at Casting Machine - Fewer Roll turn downs at the Rolling Mill - Fewer Roll change outs at Mill Stands These are all indirect benefits of having clean water return to the 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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FILTRATION BENEFITS Selection of Filters should achieve following: - Full time operators should not be required - Low or no maintenance required q - Robust “bulletproof” reliability - Low energy consumption use - Low / no chemical usage - Low Backwash water - Filter Longevity

YOU MAKE STEEL - FILTERS MAKE WATER These are the direct benefits of selecting a Filter System for an application 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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Steel Mill Recycle / Reuse Contact Water DIRECT FROM SCALE PIT - No settling Mill Scale, Solids and O&G removal

Rolling Mill Contact Water Reheat furnace

Hot Rolling Mill for shaping final Products

D Descale l Laminar

Scale S l Pit

Gravity G it Filter Filt or Pressure Filter System Dirty Backwash to De-watering

VOD - Degas Filtered Water Returns to Mill

Cooling Tower

Mill Scale Scale, Solids and O&G removal

Caster Spray Water Return Casting Machine LMF

90 ton l dl ladle

Makes scrap into steel forms

Scale Pit

Gravity Filter or Pressure Press re Filter System

Filtered Water Returns to Caster Cooling Tower

NO WATER from Filter System is discharged to the Environment ChemTreat’s Steel Industry Water Conference 9-12 to 9-14-2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission

Dirty Backwash to De-watering

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DISCUSSION OVERVIEW Mill Water Contact Systems

 FILTRATION  Design Basics  Applications  INTERNALS  Underdrain System  Media  BACKWASHING  MAINTENANCE 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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DESIGN BASICS • Flow Rate - Average and Max 1. Determines # of Filters Required - Hydraulics is sized on gpm / sq ft - Based on Size of Particles 2. Pounds of Solids (type and size) Removed - Calculated on loadings g - surface area

• Water Characteristics 1 TSS (Total Suspended Solids) - Average & Max 1. - Mill Scale - Particle Size Distribution 2. O&G (Oil and Grease) - Average & Max - Open or closed lube system - synthetic? 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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DESIGN BASICS • What is upstream of Filter System? 1. Scale Pit - Design D i and dT Type off Pit Pit; Pit R Retention t ti Ti Time - Pit Maintenance; frequency and how is it cleaned 2. Oil and Grease Removal Systems - Skimmers, Ropes, Mops, Beaches

• Where does effluent & dirty y backwash g go? 1. Effluent - Returns to Mill for Reuse - discharged to surface 2. Dirty Backwash Water - Return to Scale Pit - De-watering Circuit - mudwell - thickener - filter press 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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APPLICATIONS • Casting Machines 1 Water that is pumped from scale pit through a 1. filter system and returned to spray nozzles

• Contact Water 1. Water used to cool in steel in Rolling Process Can be on HM - Laminar, Descale, Degas

• River Ri and d Well W ll Water W Make M k up Systems S • Cooling Tower Side-stream Systems • Non Contact - Not Suitable for Sand Filters 1. Machine Water and Mold Water 2 Process Water 2. 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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FILTRATION BASICS TWO ((2)) OPERATING PHASES 1. Filtration - Removing Particles from a Water Source 2. Backwashing - Removing Captured Particles from Filter Media

TWO (2) TYPES off FILTER OPERATION 1. Continuous -Traveling Traveling Bridge Bridge, Continuous Backwash Filters 2. Semi-Continuous y - Most Gravityy and Pressure Filter Systems 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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FILTRATION ….. is a Physical Process Captured Solids

Wastewater with Suspended Solids and Oils / Grease

Clear Filtrate

Filter Medium ( IN THIS CASE SAND) - but can be any medium that captures solids to release 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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FILTRATION SPECTRUM

13 ChemTreat’s Steel Industry Water Conference 9-12 to 9-14-2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission

DESIGN BASICS Industrial Filters  Filter Bed Solids Loading g  Pressure Filters Range Between 4 and 8 lbs./ft2  Gravity Filters Range Between 1 and 4 lbs./ft2  Filter Bed Solids Loading Varies Based on:  Type of Solid Being Filtered  Size of Solid Being Filtered  Available Head

 When Does Backwash Occur  When Maximum Headloss is Reached  Pressure System Designed for 15 psi P  Effluent Quality Deteriorates

 Backwash B k hF Frequency Calculated C l l t d Based B d on Loading L di  Need to Know TSS & Flow 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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DESIGN BASICS HOW THE PROCESS WORKS  Forward Flow • Down-flow or Up-flow Filtration • Filtration Filt ti R Rate t iin gpm/ft /ft2

 Flow Control (Constant Rate vs. Variable Declining Rate) Constant Rate • Weir Levels (Gravity Filters) • Influent / Effluent Flow Control (Gravity or Pressure)

Variable Declining Rate Headloss in Each Filter Determines Flow • Better Effluent Quality • Less L W Working ki H Head d and dO Operating ti P Power R Required i d • Longer Filter Runs 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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CONSTANT verses VDR  Constant  Requires Individual Flow on each filter  Requires Individual dP on each filter • Additional Instruments to calibrate • Additional Instrument Wiring  Additional I/O required

 Variable Declining Rate  System S dP across iinfluent fl and d effluent ffl h header d  No individual Flow measurement required  Less instruments = less maintenance • Longer run time between Backwash 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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Media Depth Definitions and Filt ti Parameters Filtration P t HOW THE PROCESS WORKS  Media Depth and Solids Capture  Shallow Bed Filtration  Media Depth: 24 - 36 inches  DeepBed Filtration  Media Depth: 48 - 72 inches

 Media Size and Solids Capture

 Too Large Media  Finer Fi P Particles ti l P Pass Th Through hB Bed d  Too Small Media  Driving force must overcome media too much Hi h H High Head-loss dl can occur R Regularly l l *Capture Rate is defined by Hydraulics and size of particle 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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BACKWASHING METHODS Backwash Method

Backwash Water Rate (gpm/ft2)

Backwash Air Rate (cfm/ft2)

Comments

High BW Rates Water Only

12 - 25

High BW Rates Air Scour Only Water Only

12 - 25

2–5

High Rates for Fluidization 25 - 50% Bed Expansion Commonly Used with Fine Media and Mixed Beds

4-6

3-6

No Fluidization N Fl idi ti < 5% Bed Expansion Can only be used with Coarse Mono-Media Beds

LLow BW Rates R t Air/Water Scour is concurrently run

High Rates for Fluidization 25 - 50% Bed Expansion Commonly Used with Fine Media and Mixed Beds

Uses Less Backwash Water Than Other Designs 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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PUMPED verses STANDPIPE  Pumped p Backwash  Requires Additional Set of Pumps  Backwash Water Flow Control Loop • Additional Manual and Check Valves • Additional Power and Instrument Wiring  May Require Holding Tank for Backwash Water

 Stand-Pipe Backwash  Backwash Water Taken Directly from Effluent Pipe  No Pumps Required - Uses Height of Stand-Pipe for Backpressure  Valve Design g Allows Correct Amount of Backwash Water into 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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BACHWASHING FLOW SHEET Dirty BW Water Influent P 1 Wastewater From Mill

DeepBed

Filtration Circuit w BW Pumps

Tower

Gravity or Pressure

Clean

Filter

Backwash

Scale

Cooling

Effluent

Tank

Pit

Filtered Water

P 2

To Mill

Clean BW Water

P 3

Dirty BW Water Influent P 1 Wastewater From Mill

DeepBed Pressure

Filtration Circuit with Standpipe

Cooling Tower

Filter Scale

Effluent

Filtered Water

Pit To Mill

NOTE: Clean BW Water Each Mill might have a preference on Pumped verses standpipe backwash design. Many circuits draw clean water by placing a ChemTreat’s Steel Industry Water Conference 9-12 to 9-14-2012 , Clearwater Beach FL BW pump in the Cooling Tower cold-well. * Confidential * Do Not Duplicate without Permission

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Underdrain System Nozzle-Bottom Filter

N Nozzles/Strainers l /S i FLOOR NOZZLES FALSE-BOTTOM

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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Underdrain System y Nozzle-Bottom Filter

Typical Nozzles/Strainers Used in False-Bottom Underdrains

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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Underdrain System y Nozzle-Bottom Filter

N Nozzle l Type T Filter Fil

Dead Space

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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Underdrain System N Nozzle-Bottom l B tt Filt Filter

Coal

Sand

Nozzles

Gravel Air scour pipe

Air Distribution Holes

Concrete Piers 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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TETRA U Underdrain de d a Construction Co st uct o “Effluent Sump”

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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TETRA Underdrain Construction “Sump Cover Plates”

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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Underdrain System y Backwash Air System  BW Air Injection Location

 Under Main Floor  Directly Above Main Floor  In Between Gravel and Media

 Distribution Process  Inject Air and Water to Same Area and Use Floor Orifices to Distribute Both  Backwash Air has its own Separate Piping System for Distribution Across the Filter Area Before f C Combining with Backwash 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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TETRA Underdrain Construction “Air Laterals”

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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BW WATER AND AIR DISTRIBUTION SYSTEM • 304 SS Box Header  Wall W ll Thi Thickness k iis 3/16” • Air Laterals - Schedule 40 304 SS and Other Alloys • Air Laterals Protected from Gravel and Media  Located Under T Block™ Arch

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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Underdrain System Underdrain Distribution Block

 None  Clay Tile Block  Plastic Nozzles  Wedge-wire Screens  Metal Fabricated Underdrain  Snap-T; T-Block and “M” Block 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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TETRA Underdrain Construction “Concrete M Blocks”

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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TETRA U Underdrain de d a Construction Co st uct o “Concrete M Blocks”

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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TETRA Underdrain Construction “Plastic T and Snap-T Blocks” Purpose 1. 2 2. 3. 4. 5.

Support structure for gravel & media P Prevents t gravell from f penetrating t ti underdrain d d i Minimizes damage to filter internals from hydraulic shock Allows filtered water to pass through to the effluent Starts backwash air & water distribution across filter area

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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TETRA DeepBed® Filter Operation

34 ChemTreat’s Steel Industry Water Conference 9-12 to 9-14-2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission

GRAVEL - Tetra Configuration Layer

Depth (inches)

Size (inches)

No. 1 No. 2 No. 3 No. 4 No. 5

4 2 4 4 4

1-1/2 x 3/4 3/4 x 1/2 1/2 x 1/4 1/4 x 1/8 1/2 x 1/4

Rule of Thumb: Each Upper Layer is ~50% of the Size Below itit. 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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Filt Media Filter M di Configurations C fi ti Configuration

Media Type

Media Size (mm)

Normal Depth (inches)

Dual Media

Anthracite (Top) Sand (Bottom)

1 - 1.5 0.5 - 1

12 - 24 12 - 24

Multi-Media

Anthracite (Top) Sand Garnet (Bottom)

1 - 1.5 0.5 - 1 0.4 - 0.6

12 - 24 12 - 24 3-6

Mono-Media Mono Media

Sand or Anthracite Sand TETRA #7 or #8 Sand TETRA #5

0 5 - 2.0 0.5 20

36 - 72 48 - 72 48 - 72

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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TETRA TAMPA TESTING LAB AND WAREHOUSE

37 ChemTreat’s Steel Industry Water Conference 9-12 to 9-14-2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission

MEDIA CHARACTERISTICS SHAPE  Sphericity of > 0.8 (Perfect Sphere is 1.0)  Advantage: • Rounded R d d grains i ttendd to t rotate t t during d i BW • Uniform void spaces - Tetra Media has a 40% void space which leads to greater capture and bed penetration  Non-Round Media • Sharpp angular g ggrains interlock and increase headloss for filtration and BW. • Angular grains stick together on large flat surfaces preventing total bed cleaning 38 ChemTreat’s Steel Industry Water Conference 9-12 to 9-14-2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission

MEDIA CHARACTERISTICS HARDNESS  MOH Scale S l (1 is i ttalc l andd 10 is i di diamond) d) Sand (Quartz = 7 or Silica = 8) A th it  3.5 Anthracite 35 • Hard media minimizes attrition (wearing of media) during backwashing • Attrition leads to reduced media size (smaller Effective Size), g head losses and shorter filter runs therefore,, higher • Tetra Municipal filters longevity is 20 to 35 years before filter needs rebuilt and media needs replaced • Tetra Industrial filters have operated 5 to 30 years before filter needs rebuilt and media needs replaced 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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TETRA DeepBed™ Filter “Silica Media” MEDIA SPECIFICATION  Effective Size 1.7 to 3.0

High Uniformity Coefficient <1.40  High Sphericity >0.80  6 to 7 on MOH Scale  Acid Solubility < 5% 

Is coarse mono-media that allows greater solids capture and deeper bed penetration Leading to longer run times Carefully screened, washed and dried to the mill specific application and product mix 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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BACKWASHING Typical Mono-Media BW Sequence • Take a e filter te o off linee • Scour Media with aironlyy • Scrub media with air and water • Rinse • Put filter back on line

 2 minutes  15 - 20 minutes  5 minutes 41

BACKWASH MODE DeepBed™ Gravity Filters Air/Water Scour

42 ChemTreat’s Steel Industry Water Conference 9-12 to 9-14-2012 , Clearwater Beach FL * Confidential * Do Not Duplicate without Permission

BACKWASHING Dirty Backwash Water What To Do With Dirty Backwash Water  Transferred Directly to Upstream Scale Pit  Must Have Ample Retention in Pit to Allow for Increased Flow to Not Stir Up Settled Solids  Must Keep Pit Cleaned of Solids to Allow Room for Solids Settling  Transferred to Collection Tank for Transfer to

Solids Handling System  Mudwell, Thickener, Dewatering Equipment

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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SAND FILTRATION CHEMICAL ADDITION  Influent Filter Aid  May be Required to Remove Colloidal Particles  Add Chemical Coagulants to Produce Pinflocs  Inorganic Coagulants are Not Recommended  Must be Careful Not to Overdose

 Dirty Backwash Water for Improving Solids Settling  May be Especially Important if Dirty BW Flows to Scale Pit Upstream of Filter System

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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FILTER OPERATION - Data Collection HOW WELL IS THE SYSTEM OPERATING? It Is Important to Monitor the Water Quality of the System  Collect Influent and Effluent Samples Periodically Measure TSS and O&G  TSS versus Turbidity C ll t samples Collect l and d measure both b th TSS and d Turbidity. T bidit Once a correlation is found, the turbidity can be used to monitor the operation.  Periodically, collect Dirty BW Water Samples at Beginning and End of BW and measure TSS to check the efficiency of BW. BW 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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FILTER OPERATIONS WHY DOES THE EFFLUENT QUALITY DETERORATE? 1 Overloading Filters 1.  Check Influent TSS and Flow - Have They Increased?  Is Scale Pit Being Cleaned on a Timely Basis?  Check Backwash Frequency 2. Solids Are Colloidal (1-5 micron) in Nature  Check All Waters Entering the System  Have There Been Any Changes? Make-up Water? Has Product Mix Changed?  Are Colloids Due to Oils? 3. System Failures  Hydraulic Fluid Release from Mill Occurred  Backwash System or Valve Failure  Media Fouled 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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FILTER OPERATION Maintenance Check C 1. Check Media for Loss by Measuring from Top of Media to a Common Reference Point 2. Check Media for Abnormal Appearance 3. Check for Proper BW Air pattern 4 Check for Proper BW Water Rise Rate 4. Normal Design - 9.6 inches/minute

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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FILTER OPERATION Equipment Maintenance  Control valves

• Check for Smooth Operation • Keep Limits Adjusted Properly • Ensure Clean Air Supply

 Backwash Air Blowers

• Check Grease & Oil Monthly • Change Oil Every 6 Months ** • Grease Motor Bearings Once Per Year • Change Air Filter Every 6 Months ** • Check Belt Tension & Sheave Alignment Every 6 Months 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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Contact Water Filtration Q Questions? ti ?

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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