Transcript New Rapid Sand Filters - Whitehead

Benjamin C. Whitehead, PE
Benjamin J. Klayman, PhD, PE
Case Study: Commissioning
New Rapid Sand Filters at
Donald K. Shine Water Treatment Plant
July 2010
July 2010
Plant Flow Schematic
July 2010
South Treatment Facility – Phase IB Expansion
July 2010
Type of Filtration
Six New Conventional Rapid Sand Filters
 Roberts Leotech Underdrain w/IMS Cap
 12-inches Sand
 24-inches Anthracite
 Water and Air Scour Backwash
 1360 sq.ft. per Filter
 4 gpm / sq.ft.

July 2010
New Filter Installation


Filter Underdrain
J-Tube Riser Air
Scour Manifold
July 2010
New Filter Installation

Grout Infill

July 2010
Grout Bed
New Filter Installation

July 2010
Completed Underdrain
Filter Media Installation
July 2010
Completed Filter Cell
July 2010
Filter Backwash Equipment

Air Scour Blower
 Gardner-Denver
 Multi-stage
 300
Centrifugal
Hp
 5440 scfm @ 6.2 psig

Backwash Pump
 Perless
Pump Company
 Vertical Turbine Mixed Flow
 250 Hp
 32 MGD @ 17.5-feet TDH
July 2010
Filter Backwash
 Backwash Sequence
 Drain filter to 6-inches above
 Initiate Air Scour 2 minutes
media
 Add
4 gpm/sq.ft. Low Rate BW (8 MGD) until just
below troughs
 Stop Air Scour and continue Low Rate water only to
top of trough
 Initiate 17 gpm/sq.ft. High Rate BW (32 MGD) 4
minutes
 Low rate BW (8 MGD) for 1 minute
 10 minute settling delay
 Open effluent valve 2 minutes after filling starts

Backwash is reclaimed / returned to raw
water influent of the plant
July 2010
STF Filter
July 2010
Filter Backwash – Selectable Parameters
July 2010
Backwash with Air Scour
July 2010
Backwash with Air Scour
July 2010
Backwash
July 2010
Backwash
July 2010
MDNRE Requirements
2 Consecutive 15 min. NTU > 1.0
 2 Consecutive NTU > 0.5 first 4 hours
 2 Consecutive NTU > 1.0, 3 consecutive months
 2 Consecutive NTU > 2.0, 2 consecutive months

B&V / City of Wyoming Start-up Goals
Maintain NTU < 0.3 (<0.1 normally)
 < 0.1 NTU @ 7 MGD

July 2010
Commissioning Plan
How do we get there?
 Careful Planning
 Start Slowly
 Filter to Rest
 Monitor/Operate Closely
 Flow
 Turbidity
 Headloss
July 2010
Commissioning Pre-requisites
 Media Washing/Screening
 VOC testing
 Chlorination
 Instrumentation / Alarms
 Monitoring / Trending
 SCADA Control
 Backwash Equipment
 Backwash Sequence
 Transfer Pumping
July 2010
Commissioning Plan
 Initial Start-up:
Initiate Filter Off-line (Filter-to-Waste)

1 MGD, Filter-to-Waste until < 0.3 NTU
Filter
On-line: 1 MGD
> 0.3 NTU, Initiate Settling-delay: 4 hours
 Re-test: <0.1 NTU up to 3 MGD


Seasoning:
2 weeks up to 3 MGD
1 week off-line
July 2010
Commissioning Plan
Performance Test:
 Run Filter Several minutes
 Backwash
 Place On-line, 1 to 3 MGD
 Ramp 0.5 MGD @ 30 min intervals
>
0.2 NTU Initiates Continuous Monitoring
 > 0.3 NTU Initiates Filter-to-Waste

Ramp to 7 MGD for 1 hour < 0.1NTU
July 2010
SCADA Screen – STF Filter Overview
July 2010
Filter No. 13 Start-up
0.8
Flow
Head Loss
Turbidity
Flow (MGD) / Head Loss (ft)
7
0.7
6
0.6
5
0.5
4
0.4
3
0.3
2
0.2
1
0.1
0
1/4
1/5
1/6
1/7
1/8
Time
July 2010
1/9
1/10
1/11
0
1/12
Turbidity (NTU)
8
Filter Performance (Results)
 Filter Influent Turbidity: +/- 0.3 NTU
 Filter Effluent Turbidity: < 0.1 NTU @ 7 MGD
 Filter Effluent Turbidity: 0.02-0.07 after Initial
Commissioning & Current Conditions
 Filter Headloss: 1 to 7.5-feet
 Run Time: 200 hours - New and Existing
Filters
 4X
longer after expansion
 Previously 40-60 hours
July 2010
Filter Performance

Meurer Research Inc. Plate Settling Equipment
July 2010
Field Engineering Improvements

Reduced Washwater Quantity
 Reduced High Rate
 Total Wash Volume
Wash: 10 minutes to 4 minutes
= 75 gal / sq.ft. (100,000 gal)
 Industry Standard = 150-180 gal / sq.ft. (250,000 gal)
 Allows for 5 Consecutive Backwashes to Reclaim
Operator Adjustable Settling Delay
 Washwater Launder Stabilization
 Headloss Instrumentation Calibration
 Air Distribution Optimization

July 2010
Questions?
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July 2010