Sustainable BNR Process Aeration Design and Optimization

25 Pages·2015·2.08 MB·English

Sustainable BNR Process Aeration
Design and Optimization
NYC DEP BEDC In-House Design
Presenter: Caitlin Hunt
Co-Authors: Natalia Perez, Alexander Lopez, Patrick O’Connor
Jiren He
Agenda
•  Jamaica Bay Nitrogen Consent
Order
•  Brief Overview of Coney Island
BNR Upgrade
•  NYC WWTP Aeration System
Benchmark
•  BioWin Modeling
•  Process Air Blowers and BNR
Process Aeration Requirements
•  Process Air Piping
•  Diffuser Design
Coney Island WWTP
•  DO Control
•  Channel Mixing
•  Questions
2
Jamaica Bay Nitrogen Consent Judgment
Jamaica
Bay
3
Jamaica Bay Nitrogen Consent Judgment
Jamaica WWTP
26th Ward WWTP
Coney Island WWTP
Rockaway WWTP
•  Aggregate limit on the total pounds of
nitrogen discharged into Jamaica Bay
•  Coney Island BNR Upgrade
•  Cost-effective BNR upgrade
•  36,400 lbs/day limit as of 08/2014

4
Coney Island BNR Upgrade
•  Treats domestic and combined •  How do we accomplish Step
sewer wastewater Feed BNR?
•  110 MGD dry weather flow o  Increase SRT
•  165 MGD flow through o  Aeration requirements
secondary treatment expected to increase to meet
nitrification requirements
•  220 MGD wet weather flow
o  Create anoxic zones for
•  4 aeration tanks with a total
denitrification
volume of 16.7 MG
5
Coney Island BNR Upgrade
Anoxic and Oxic Zones
RAS
PRIMARY
Pass A
EFFLUENT
PRIMARY
EFFLUENT Pass B
PRIMARY
EFFLUENT
Pass C
PRIMARY
EFFLUENT
MIXED
Pass D
LIQUOR
Oxic Zone Baffle Wall
Anoxic/Swing Zone
6
NYC WWTP Aeration Benchmark
Airflow per Lbs of CBOD Removed At NYC WWTPs
Airflow/Lbs CBOD Removed Ratio
2.00
1.80
15 MGD
1.60

d
e
1.40
v
o
m
1.20
e
R

O 1.00
B
214 MGD
C
/ 0.80
w 27 MGD
o 56 MGD
l
f 0.60
r 78 MGD 93 MGD
Ai 28 MGD
0.40 88 MGD
28 MGD
112 MGD
0.20
0.00
Data taken from historical plant monthly data from 1/2013 – 12/2013.
*Rockaway data was taken from 11/2011 – 10/2012 7
BioWin Modeling
•  BioWin was used as a process modeling tool to predict aeration requirements
at different loadings and wastewater temperatures
•  Model Calibration is important
•  Used for aeration system design
o  Optimize operations and equipment at future average conditions
o  Predict treatment results
o  Stress test BNR operation at maximum month conditions
8
Process Air Blowers
Estimated Blower Energy
Consumption (kWh/day)
45,000

) 40,000
y
a
D 35,000

r
e 30,000
p
h 25,000
W
•  4 Dresser-Roots two-stage 20,000
k
(
centrifugal process air blowers y 15,000
g
r 10,000
rated at 23,800 SCFM at 8psi e
n
E 5,000
•  3 duty and 1 standby 0
10/18/2012 10/18/2013 10/18/2014
•  Maximum Capacity of 71,400
Date
SCFM at 8psi
•  Originally manufactured in 1958
and refurbished in 1990s
99
Coney Island Aeration Requirements
Coney
 Island
 Airflow

Historical
 Airflow
 (CFM)
  Es=mated
 BNR
 Airflow
 (CFM)

70,000

60,000

50,000

)
M
F
C 40,000

(

w
o
30,000

l
f
r
i
A
20,000

10,000

0

Date
10