December 2009 Presented to: ASTM F25 Environmental Seminar
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Transcript of December 2009 Presented to: ASTM F25 Environmental Seminar
December 2009 1
Standardization for Oil Water Separator (OWS) and Oil Content Monitor (OCM) Systems In-Service Engineering Agent Perspective
December 2009Presented to: ASTM F25 Environmental Seminar
Presented by: Ray A. Morales US NAVY (NSWCCD)
December 2009 2
In-Service Engineering Agent Responsibilities
• Provide technical support to the fleet for the in-service Oil Pollution Abatement (OPA) system including OWS, OCM, and transfer system.
– Test and Evaluation– Equipment Modifications– Technical Assistance– System Certification and Training
• Provide support for the acquisition programs– Design and Specification reviews
Standardization for Oil Water Separator (OWS) and Oil Content Monitor (OCM) Systems
December 2009 3
Applicable Standards & Regulations for Navy OWS and OCM systems
• Navy Ships are considered public vessels– Department of Defense (DOD 4715.6-R1)– Office of Chief of Naval Operations Instruction (OPNAVINST 5090.1C)– American Bureau of Shipping (ABS) Naval Vessel Rules (NVR) – USCG (Title 46 CFR Part 162.050 - Pollution Prevention Equipment)– International Maritime Organization (IMO) ( MEPC.107(49) )
• ASTM Standard– ASTM F2283 “Standard Specification for Shipboard Oil Pollution
Abatement System”• Provides general design requirements• Refers to MEPC.107(49) for OWS and OCM requirements.
Standardization for Oil Water Separator (OWS) and Oil Content Monitor (OCM) Systems
December 2009 4
Challenges for OWS and OCM systems• Performance issues
• Reliability
• Maintenance costs
• Obsolescence issues
• Capital costs of unique systems
• Lack of Standards to ensure performance, reliability, and maintainability
Standardization for Oil Water Separator (OWS) and Oil Content Monitor (OCM) Systems
December 2009 5
Testing of MEPC. 107(49) Certified COTS OCMs
Objective
To conduct laboratory testing of selected IMO MEPC 107(49) certified COTS OCMs to evaluate their performance under various operating conditions and in the presence of contaminants to determine if these units would be suitable for shipboard use in Navy vessels based on direct comparison with the in-service OCM unit.
Case Study –
Testing of Commercial off-the-Shelf (COTS) MEPC. 107(49) Certified Oil Content Monitors (OCMs)
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Test Set-up
Testing of MEPC. 107(49) Certified COTS OCMs
WATER PUMP
OIL INJECTION SYRINGE PUMP
DISPERSER
WATER PURIFICATION
THERMO SCANNER
DATA ACQUISITION
DRAIN FUNNEL
Sediment Pre-filter
5 Micron Filter
0.5 Micron Filter
TAP WATER FEED
FLOW METER
PRESSURE GAUGE / TRANSDUCER
SAMPLE VALVE
AIR PUMP
PRESSURE RELIEF VALVE
P
P
CONTAMINANT INJECTION
SYRINGE PUMP
WATER FEED TANK
PRESSURE GAUGE
CONTAMINANT TANK
RECIRCULATION PUMP
WATERHEATER
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Screen shot of data acquisition software
Testing of MEPC. 107(49) Certified COTS OCMs
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Testing Performed
• Pre-test Checks:– General checks to determine installation/ interface requirements and to ensure that OCM and testing
equipment are operational• Calibration Test:
– To verify OCM calibration at 0 PPM, 15 PPM and maximum oil concentration that the OCM can measure• Oil Droplet Size Distribution Test:
– To determine deviations of the OCM calibration due to variations in oil droplet size distribution• Flow/Pressure Range Test
– To determine deviations of the OCM calibration within the design Flow rate and Pressure Ratings and to determine if the OCM is fail-safe beyond the design flow/pressure range.
• Temperature Range Test– To determine deviations of the OCM calibration within the design temperature Range.
• Different Oil Types Test– To determine deviations of the OCM calibration in the presence of different types of oils (i.e., the oil mix#
components separately; DFM, 9250, 2190, JP-5 and Synthetic oil) • Response Time Test
– To determine time required by the OCM to alarm once high oil content is present. • Contaminant / Interferences Tests (color, air, solids, emulsions, salinity) – Decision
Making Test– To incrementally change each given parameter to determine at which point: (1) The OCM measurements
are affected and (2) The OCM decisions are affected (i.e., allows overboard discharge or recycle to the oily waste holding tank)
Testing of MEPC. 107(49) Certified COTS OCMs
December 2009
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Conclusions drawn from this testing• The COTS OCMs tested failed to detect free oil, failed to accurately measure oil under the conditions expected in the effluent of a failing OWS treatment system and required highly mechanically dispersed oil for accurate measurements.
• The COTS units tested produced critical failures (would allow overboard discharge of > 15PPM oil-in water), with and without interferences/contaminants, when tested under the conditions expected from a failing OWS treatment system .
• COTS units tested did not accurately measured different types of oils (affected calibration)
• Then COTS units tested required significant routine maintenance to keep operating properly. The sampling cell of the COTS units were cleaned between tests to ensure a zero baseline and prevent drift in the readings.
• Response time results were not consistent with requirement (e.g., < 5 secs)
• COTS units tested did not provide for “Fail-safe” design: – Continued operation even with no flow allowing “by-passing” the OCM while the data recorded shows
acceptable effluent. This could allow continued operation of OWS even with unacceptable overboard discharge while zero (0) oil PPM is recorded.
– Design does ensure diverter valve default position to recycle during all possible failures modes
• COTS units tested were designed and calibrated to meet MEPC.107(49)
Testing of MEPC. 107(49) Certified COTS OCMs
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Test Results/ FindingsOil Droplet Size Distribution Test (Disperser’s settings)
Droplet size distributions at various disperser's speeds
0
20
40
60
80
100
120
0 10 20 30 40 50 60 70 80
Droplet diameter, um
Cu
mu
lati
ve %
oil
dro
ple
ts 6,000 RPM (Min)
8,000 RPM (Std)
10,000 RPM
12,000 RPM
14,000 RPM
16,000 RPM
18,000 RPM
20,000 RPM
22,000 RPM
23,00 RPM (Max)
Testing of Commercial off-the-Shelf (COTS) Oil Content Monitors (OCMs)
December 2009
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Test Results/ FindingsOil Droplet Size Distribution Test (Disperser’s settings)
Oil Droplets Micrographs: 15 PPM oil injection at 8,000 RPM Disperser’s Speed (Standard Conditions)
Testing of MEPC. 107(49) Certified COTS OCMs
46µm
28µm
25µm
6µm28µm
6µm
4µm3µm
32µm
29µm
6µm
6µm
35µm
28µm
8µm 3µm2µm
14µm
5µm
13µm
12µm
13µm
5µm14µm
9µm
6µm
32µm 5µm
3µm
December 2009
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Test Results/ Findings Oil Droplet Size Distribution Test
Sample Conditioning Test at 15 PPM Oil Injection
0
5
10
15
20
25
0 6000 12000 18000 24000
Disperser's Speed (RPM)
Oil
Co
nce
ntr
atio
n
(PP
M)
Navy OCM 1 OCM 2 OCM 3
Testing of MEPC. 107(49) Certified COTS OCMs
December 2009
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Test Results/ Findings
Testing of MEPC. 107(49) Certified COTS OCMs
Different Types of Oils Test
0
5
10
15
20
25
bilge mix diesel fuelmarine
2190 lube oil 9250 lube oil JP5 synthetic
Different Types of Oils
Oil
Co
nce
ntr
atio
n, P
PM
v
ET-35N OCM 1 @ 8k RPM OCM 1 @ 12K RPMOCM 2 @ 8k RPM OCM 2 @ 20k RPM OCM 3 @ 8k RPMOCM 3 @ 22K RPM
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Test Results/ FindingsResponse time
Testing of MEPC. 107(49) Certified COTS OCMs
Response Time, Secs(at 40 PPM oil Injection)
31
812 11
0
5
10
15
20
25
30
35
40
45
50
Navy OCM 1 OCM 2 OCM 3
OCM Units
Resp
on
se T
ime (
Seco
nd
s)
Time to Detect Oil Time to Alarm
31
11
43
14
Target Response Time, 5 secs
Required by MEPC.107(49)
NOTE : For this test oil was injected at 40 PPM oil at the corresponding optimum disperser’s speed for each OCM:The calculated time for the oil to travel from the injection point to the OCM was subtracted from the time measurementsThe blue columns represent the first time that the OCM detected any oilThe total height of the columns represents the total time for the OCM to alarm
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Testing of MEPC. 107(49) Certified COTS OCMs
List of Contaminants
Test Type Components Description Composition
1.8a Color Dye Formulabs STD Blue Liquid, Lot #3786
1.8b Air Air bubbles Injected with syringe pump for low concentrations and low pressure air with pressure regulator and rotameter
1.8c Solids Iron Oxide (Fe3O4) Particle size distribution: 90% below 10 microns and 10% up to 100 microns
50/50 by weight mixture
SAE fine test dust ISO Fine (0-80 microns)
1.8d Emulsions Allied P-98Mil-D-16791AFFFSimple Green
Emulsifier/detergent mixture
Mixture of equal volumes, prepared using bench-top shaker
1.8e Salt Water “Instant Ocean” Refer to Appendix A for ingredients
Up to 6% of salt in water
December 2009
Test Results/ Findings Contaminant/Interference/Salinity Test – Summary
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Test Results/ FindingsContaminant/Interference/Salinity Test – Summary
Testing of MEPC. 107(49) Certified COTS OCMs
• The Navy in-service OCM was not affected by the presence of interferences/ contaminants at low concentrations. It produces unnecessary recycle at high concentrations of these interferences/contaminants and “fails safe.”
• The COTS unit tested produced critical failures with and without interferences/contaminants when tested under the conditions expected from a failing treatment system.
•The COTS unit tested was not significantly affected by the presence of interferences/contaminants when the sample was conditioned at very high disperser’s speed.
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Potential Areas of Standardization for OWS and OCM Systems
• OWS and OCM– Revise ASTM F-2283– Different Type of Oil test – Reliability and maintainability
• OCM– Free oil and droplet size distribution tests – Fail-safe design
Testing of MEPC. 107(49) Certified COTS OCMs
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(BACK UP SLIDES)
Testing of MEPC. 107(49) Certified COTS OCMs
END
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Test Approach
• Test Set-up is shown in next figure
• Baseline - Navy OCM calibration standard conditions:– Oil type:
• Mixture by vol 50% diesel fuel, 25% 2190 lube oil, 25% 9250 lube oil (used for years as standard in all Navy testing)
– Sample conditioning: • In-line disperser set at 8,000 rpm to produce approximately 20% oil
droplets above 20 um diameter (expected in the effluent of a failing parallel plates OWS)
– Performance results from the in-service OCM unit
• OCMs tested within a range of various operating conditions, oil types and contaminants/ interferences
• Oil concentration was determined by mass balance of oil injected into the water stream
Testing of MEPC. 107(49) Certified COTS OCMs
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Test Results/ Findings Calibration Test
Testing of MEPC. 107(49) Certified COTS OCMs
OCM Unit
0 PPM
Oil Injection (1)
15 PPM
Oil Injection (1)
15 PPM Oil Injection (at higher disperser’s speed)
12,000 RPM 20,000 RPM 23,000 RPM (2)
Navy OCM (ET-35N)
0.16 15.07 - - -
OCM 1 0.78 6.57 15.90 - -
OCM 2 0.01 0.12 - 14.99 -
OCM 3 0.01 0.08 - - 7.91
Notes: (1) Standard disperser’s speed (8k RPM).
(2) maximum disperser’s speed
(3) OEM of COTS units indicated that their units were calibrated to meet the MEPC. 107(49) and that
recalibration will invalidate this certification
December 2009
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Test Results/ FindingsOil Droplet Size Distribution Test:
OCM Decision at 22 PPM Oil Injection
05
1015
2025
30
0 6000 12000 18000 24000
Disperser's Speed (RPM)
Oil
Co
nce
ntr
atio
n
(PP
M)
Navy OCM 1 OCM 2 OCM 3
Testing of MEPC. 107(49) Certified COTS OCMs
Acceptable Region
Critical Failure - >15 PPM Overboard Discharge
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Conclusions Summary
• The COTS OCMs tested failed to detect free oil, failed to accurately measure oil under the conditions expected in the effluent of a failing parallel plate OWS, and required highly mechanically dispersed oil for accurate measurements
– These OCMs were not designed to condition the sample – The accuracy of these units will depend on the sample conditioning of the secondary treatment effluent– These units may produce unacceptable overboard discharge if the failure of the treatment systems produces large oil droplets (e.g., cracked membrane, etc.)
• The measurements of the OCMs tested were not significantly affected by variations in pressure or temperatures
•The measurements of all the units tested, including the In-service OCM, are dependent on the type of oil present.
Testing of MEPC. 107(49) Certified COTS OCMs
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Conclusions Summary (Cont.)
• The response times of all the MEPC. 107(49) Certified OCMs tested exceeded the maximum of 5 seconds required for this certification (e.g., 11 to 43 seconds)
• The ET-35N was not affected by the presence of interferences/ contaminants at low concentrations. It produces unnecessary recycle at high concentrations of these interferences/contaminants and “fails safe.”
• The COTS unit tested produces critical failures with and without interferences/contaminants when tested under the conditions expected from a failing parallel plate OWS
•The COTS units tested were not significantly affected by the presence of interferences/contaminants when the sample was conditioned at very high disperser speeds.
• OEM of COTS units indicated that their units were calibrated to meet the MEPC.107(49) and that recalibration will invalidate this certification.
Testing of MEPC. 107(49) Certified COTS OCMs
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Conclusions Summary (Cont.)
The sampling cell of the COTS units were cleaned between tests to ensure a zero baseline. These units may require self-cleaning capabilities for proper operation.
• COTS units continued operation even with no flow allowing “by-passing” the OCM while the data recorded shows acceptable effluent.
• COTS units do not provide signal output to energize the diverter valve when the OCM is operational and readings below 15 ppm as required for a “fail-safe” installation.
Testing of MEPC. 107(49) Certified COTS OCMs
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Recommendations Summary
• Performance and reliability shipboard demonstration should be conducted prior to considering these units for shipboard installation.
• Integration requirements should be developed to ensure that the “fail- safe” intent is met if these units are considered by the Navy for shipboard use:
–Diverter valve “Fail-safe” requirements•Diverter valve position to overboard only when received signal from OCM.•Default position of the diverter valve shall be to the OWHT when
–Normal de-energized position–No signal input from the OCM–Actuator failure–Electrical power supply failure
–OCM signal output “Fail-safe” requirements:•OCM shall have consecutives acceptable readings for at least 1 minute prior to send signal to the diverter valve to:
–Verify that the effluent is acceptable prior to being sent overboard.–To avoid constant cycling of the diverter valve that can result in unacceptable overboard discharge and valve failure.–OCM signal shall be immediately interrupted if any reading is unacceptable
• The units tested use some variation of light scattering technology. Other available technologies such as UV fluorescence should be evaluated.
Testing of MEPC. 107(49) Certified COTS OCMs
December 2009