Transcript No Slide Title

A Review of
State-of-the-Practice Equipment
at the Plum Creek WWTP
By
Tim Grotheer
Plum Creek Wastewater Authority
&
Dave Oerke
RTW Professional Engineers & Consultants, Inc.
Presented at the 2002
Joint RMAWWA/RMWEA Annual Conference
Steamboat Springs, CO
Presentation Outline
Quality Equipment
Process Flexibility
Strict Effluent Limits
Design Approach
Plum Creek
Wastewater Authority
PCWA Project Overview
 EPA Award Winning WWTP
 Expansion from 2.7 to 7.3 MGD
 2X to 3X Growth Expansion
 Encroaching Development Near WWTP
 Current Organic Load has been
133% of Design at Times
PCWA Project Overview Cont…
 Regulatory Issues
 Future Ammonia Limit <1.0 mg/l
 Future Phosphorus Limit <0.13 mg/l
 Downstream use of South Platte Water
 Maximum Use of Existing Facilities
 Effluent Reuse Potential
PCWA Service Area Population
Castle Pines
North
Castle Pines
Metro
Castle Rock (from
Uplan)
Total PCWA (from
Uplan)
Revised Castle
Rock
Revised Total
PCWA
100,000
90,000
80,000
70,000
Population
60,000
94,276
78888
78,631
63243
66,296
50,000
50,169
50,651
43923
40,000
30,000
20,000
36,661
29,796
22,671
10,000
8,745
8,745
8,745
4,763
6,900
6,900
2005
2010
4,500
0 2,625
2000
2015
2020
Year
Figure 3-1
PCWA Service Area Population Projections
PCWA Utility Plan
Rothberg, Tamburini & Winsor, Inc.
Organic Loading
16000.0
14000.0
PCWA Plant #1 Organic Loading
30 Day Averages
8700 lbs. - PCWA Rated Organic Capacity
TREND
Pounds of BOD
12000.0
10000.0
8000.0
6000.0
4000.0
6898 lbs. - Permitted Organic
Capacity
2000.0
0.0
O
N
O
N
J a Fe M
A
M
J
J
A
S
D
J
F
M
A
M
J
J
A
S
D
J
F
nb- ar- pr- ay un- ul-0 ug- ep- ct- o v- e c- an- eb- ar- pr- ay un- ul-0 ug- ep- ct- o v- e c- an- eb00 0
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00 0
01 0
01 -0
01 1
00 0
00 00 00
01 01 01 0 1 0 1 0 2 02
0 00
1 01
0
0
1
Effects of Higher Flows on Concentrations
Wastewater Flows Plotted against Phosphorus Concentration
12
10
1.600
Wastewater Flows
Phosphorus Concentrations
1.400
1.200
1.000
6
0.800
0.600
4
0.400
2
0.200
0
0.000
mg/L
Million Gallons per Day
8
Planned Facilities
 Three Oxidation Ditches and Secondary
Clarifiers Capable of BNR
 Alum Addition to:
1. Flocculating Secondary Clarifiers
2. Floc Basins prior to Tertiary Filters




Filtration & UV Disinfection
Biosolids Handling Facilities
Odor Control
Addition to the Administration Building
and New Maintenance Building
Site Plan Schematic
INFLUENT FLUME
METERING STRUCTURE
AWT
BLDG
MAINTENANCE
BLDG
HEADWORKS
BLDG
ADMIN
BLDG
BIOSOLIDS
LAGOONS
FERRIC
CHLORIDE
BLDG
CONVERTED
AEROBIC
DIGESTERS
CONVERTED CENTRATE/
FILTRATE HOLDING TANK
BLOWER
BLDG
SOLIDS PROCESSING
BLDG ADDITION
& TRUCKBAYS
OXIDATION
DITCH BASINS
ALUM STORAGE
BLDG
SOLIDS
PROCESSING
BLDG
ULTRAVIOLET
DISINFECTION
BLDG
RAS/WAS
BLOWER
BLDG
SECONDARY
CLARIFIERS
TERTIARY
FILTER BLDG
ADMIN BLDG
ADDITION
NEW FACILITIES
CONVERTED EXST FACILITIES
EXST FACILITIES
STORMWATER
DETENTION POND
Planned Facilities –
Oxidation Ditches
 BNR with Anaerobic Selectors and
Anoxic/Oxic Portions
 Flexibility to Vary Detention Time Using
Vertical Mixers with VFD Drives
Oxidation Ditch Schematic
FINE BUBBLE
DIFFUSERS
CENTRATE/FILTRATE
RECYCLE PIPE
OXIDATION
DITCH NO. 3
ANAEROBIC
SELECTOR
BASIN
ANAEROBIC
SELECTOR
MIXER
OXIDATION
DITCH NO. 2
RAS CHANNEL
PIPE
UTILIDOR
OXIDATION
DITCH NO. 1
DO PROBE #1
ORP PROBE #1
RAS SUSPENDED
SOLIDS ANALYZER
DO PROBE #2
ORP PROBE #2
MLSS SUSPENDED
SOLIDS ANALYZER
Automatic SCADA
Aeration Control
 Blowers
 Single – Stage Centrifuge
 Unique Inlet/Outlet Vanes
 3-450 HP (includes 1 standby)
 1-450 HP Future
 Significant Power Savings
 Match Energy Consumption to:
 Influent Flow
 Dissolved Oxygen
 ORP
 Touch-Screen Control Panel
 Greater Turndown to 30%
90
15%
70
60
multi– stage
50
w w t p
positive disp
100
90
80
%
70
c a p a c i t y
60
50
40
e f f i c i e n c y - %
30%
i s e n t ro p i c
80
single–stage
8400
Peak 8360 ACFM 476 HP
Volume (ACFM)
8300
Potential Savings
254,040 HP / YR
$13,270/yr
8200
@ $0.07/kW
8100
$265,414 / 20 YR
8000
7900
Min 7840 ACFM 447 HP
7800
2pm
(75)
4pm
(70)
6pm
(70)
8pm
(60)
10pm
(55)
12am
(50)
2am
(45)
4am
(45)
6am
(50)
8am
(55)
10am 12pm
(60)
(70)
Time/Temperature
8000 scfm @ Varying Temp
Planned Facilities – UV
Disinfection
Ultraviolet Disinfection
State of the Art
Better Water Quality for Reuse
Planned Facilities - Filtration
As wastewater flows increase, phosphorus
concentrations must decrease to continue to meet
standards. Filtering the water will enable us to meet
the standards and
1. Allow unrestricted
reuse under Colorado
regulations (on parks
and open space)
2. Facilitates acceptance
of augmentation plans
Planned Facilities – Biosolids
Centrifuges dewater
(remove water) from
the biosolids
Less available land
close in
Planned Facilities –
Odor Control
Encroaching development
Original Concept - Chemical Scrubbers
Selected Equipment – Ionization
Design Procedure to Ensure
Quality Equipment
Interview Other WWTP Operators
 Phone Interviews
Tours
Europe (Germany, Holland, and Great Britain)
United States (Florida, Arizona, and Colorado)
 PCWA Staff Preferences
Input from RTW Engineers/Operators
Design Procedure to Ensure
Quality Equipment
8 - Sole Source Specs
18 Tight Specs Listing ONLY
2 Manufacturers
Challenging Substitution Requirements
Detailed Prequalification of
General and I+C Contractors
Project Design Considerations
Cost Reductions:
 Odor Control
 Filters
 Other
Phasing of Equipment to
Accommodate Growth
Constructability Review and
Value Engineering
Potential Users & Demands
Castle Pines North Other Castle
Golf Course
Pines Uses
Country
Club
Golf Course
International
Golf Course
Plum
PCWA
Plant #1
Woodlands
The
Meadows
x
Red Hawk
Cedar Hill
Cemetery
Founders
Village
PCWA
Plant #2
(currently
off-line)
Downtown
Dawson
Ridge Plum Creek
Summary
Good Proven Equipment
More Streamlined Submittal Process
Easier Startup Process
Significant BNR Activated Sludge
Process Flexibility
Summary Cont…
Concrete Tank Savings
with Deeper Tanks
Lower Power Consumption
High Quality Effluent
Good Odor Control
Team Effort