Comparison of
Ballast Water Treatment Systems
INTERTANKO North American Panel Meeting
Debra DiCianna Senior Environmental Solutions Consultant
Stamford, CT
18 March 2013
2
Overview
Ballast Water Management (BWM) Convention Status
Ballast Water Management System (BWMS) Approvals
Statistics on BWMS
Processes used for Ballast Water Treatment
Comparison of BWMS
Limitations of Systems
Available Data from
Performance Testing
Conclusion
3
BWM Convention Status
As of 6 March 2013, ratified by:
36 Member States/Parties
29.07% of World Tonnage
Entry into Force – 12 months after ratification by:
30 States
35% of World Tonnage
Needed
5.93% of World Tonnage
4
BWMS Approvals
BWMS No. of Systems
Available or In-Development 70+
MEPC.174(58) Type Approval Certificate ~33*
Type Approved BWMS – Explosion Proof 3
IMO Final Approval 6
IMO Basic Approval 16
USCG Type Approval 0
USCG Alternate Management System (AMS) 0
The number reflects verified approvals for a BWMS manufacturer –
not the number of specific models approved and excludes 2 systems
removed from the market
5
BWMS Statistics
Category Value
No. of BWMS Requiring Treatment during Intake & De-Ballasting 29
No. of BWMS using Active Substances 19
No. of BWMS Requiring Storage of Chemicals 15
No. of BWMS Requiring Storage of Waste Products 1
Minimum Capacity (m3/hr) 0
Maximum Capacity (m3/hr)* 16,200
*Maximum capacity only includes specific models listed in documentation.
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Processes Used for Treatment
Separation Technology
Natural physical differences
in organisms
Chemically “induced” differences
(i.e., coagulation, flocculation)
Disinfection Technology
Killing organisms; or
Altering organisms such that
they cannot reproduce or
are no longer viable
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BWMS: Without Filtration
Four IMO Type Approved Systems do not use any type of
separation technology
Treatment technologies included:
Electrolytic Chlorination
Ozone
Deoxygenation
Vacuum Reactor + UV
8
Breakdown of Filter Size in Type Approved BWMS
No Filter (4)
10 μm Filter (1)
20 μm Filter (2)
40 μm Filter (9)
50 μm Filter (9)
55 μm Filter (1)
No Details (7)
29 Type Approved BWMS use
some type of separation
technology.
Note: Some BWMS use multiple sized filters.
The smallest filter size is noted in the chart.
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Variety of Separation Technology Used
Disk
Drum
Hydrocyclone
Mesh
“Smart Pipe”
Screen
Stacked Disk
Stacked
Photo Source: http://www.filtersafe.net
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Disinfection Technologies
Chlorination (12 BWMS)
Electrolytic Chlorination (9 BWMS)
Addition of Chlorinated Compounds (i.e., Purate®, Calcium hypochlorite, Sodium
hypochlorite) (3 BWMS)
Ozone (2 BWMS)
Oxidation (2 BWMS)
Deoxygenation (1 BWMS)
Ultraviolet (UV) Radiation (12 BWMS)
Plasma Arc + UV (1 BWMS)
Ozone + UV (1 BWMS)
Vacuum Reactor + UV (1 BWMS)
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“Chlorination” Chemistry in Seawater
In seawater, these chlorination processes generate hypobromous
acid (HOBr) which is a highly effective biocide/germicide
Bromine substances are more effective biocides/germicides than
chlorine substances
Chlorination
Electrolytic generator produces
NaOCl
NaOCl →Na+ + OCl-
OCl- + Br- → OBr- + Cl-
OBr- + H+ → HOBr
Ozone
Bromide ion in seawater
decomposes O3.
O3 + Br- → O2 + OBr-
O3 + OBr- →2O2 + Br-
O3 + 2Br- + OH--→HOBr + BrO3-
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UV Radiation
Organisms are inactivated by the absorption of light that causes a
photochemical interaction altering molecular components essential
to cell function – resulting in injury or death of exposed cells
No chemical interaction
Disinfection by products (DBP) formation
rates are not significantly impacted
when chlorine and related
products are used
Photo Source: http://www.gloen-patrol.com
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Breakdown of BWMS Model Capacities
0
5
10
15
20
25
No
. o
f S
ys
tem
s
BWMS Capacity (m3/hr)
Ozone
Deoxygenation
Oxidation
UV
Flocculation
Chlorination
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Technical Specification Comparison
Capacity
(m3/h)
Footprint (m2) Power (kW) Weight (kg)
Minimum Maximum Minimum Maximum Minimum Maximum
BWMS with Chlorination
300 3.7 7.0 12 29 1113 2145
500 2.0 7.6 3 40 1700 3360
1000 6.4 12.5 30 92 1933 3650
1500 7.1 18.9 45 137 2473 4885
2000 6.8 23.5 60 182 3321 6330
3000 4.1 43.0 97 272 5151 9330
4000 4.7 20.7 119 320 8200 11040
5000 5.3 23.8 157 400 8800 13600
BWMS with UV
250 2.4 8.0 11 33 900 2300
500 1.3 16.0 15 77 1386 3300
1000 2.8 29.0 30 154 3941 5500
3000 13.9 48.0 90 462 13000 13170
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Limitations: Final Approval & Type Approval
Specific limitations listed in IMO
Final Approval and Type Approval
Certificates
Salinity
Temperature
UV intensity
Dosage
Holding time
Need consistency in level
of detail in Type Approval
certificates
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Type Approval Limitations for BWMS with Chlorination
Treatment Concentration (mg/L) Limitations Notes
10 mg/L Total Residual Oxidants (TRO) 1 PSU,
Less than 40 °C
Additional protection needed if installed on deck
and exposed to heavy seas.
2.5 mg/L TRO None
20.0 mg/L TRO None Discharge TRO = 0.03 mg/L
10 mg/L TRO 3 PSU,
Minimum Temperature 5 °C
Intake - 2.5 mg/L TRO;
Deballasting - 0.15 mg/L TRO None
2.0 mg/L TRO None
10 mg/L TRO 10 PSU
15.0 mg/L TRO 15 - 35 °C
3.0 mg/L TRO None
9.5 mg/L TRO;
(TA states 7.4 mg/L TRO)
3 PSU or
High Salinity Source Needed Discharge Concentration = 0.1 mg/l
9 mg/L TRO 15 PSU
5 mg/L Cl02 0 - 50 °C Minimum Holding Time: 48 hours
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Type Approval Limitations for BWMS with UV
Limitations
5 - 45 °C
45% (10 mm) minimum UV transmittance at 254 nm
0-50 °C
UV-Intensity Minimum Level: 100 mJ/cm2
Wavelength - 254 nm
Minimum Radiation Dosage of:
83% for 250 m3/h model, 85% for 50 m3/h model, and 93% for 1500 m3/h model.
Additional protection needed if installed on deck and exposed to heavy seas.
UV Intensity Meter: 10.39 - 150 W/m2;
Intensity below 10.39 implies ballast water not treated in accordance with TA certificate
UV Intensity Meter Acceptable Range: 100 - 2500 W/m2;
Intensity below 100 implies ballast water not treated in accordance with TA certificate
Pressure: 10 bar
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Testing of BWMS
Testing
Land-based
Shipboard
Limited data publicly-available for
Type Approved BWMS
Need to verify untreated ballast
water meets requirements for the
number of organisms
Issues with USCG requirements
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IMO vs. USCG Requirements
IMO USCG
Testing G8 ETV Protocol
Discharge Standard
Terminology
Regulation D-2 states
“discharge less than 10 viable
organisms per cubic meter
greater than or equal to
50 micrometers in minimum
dimension”
33 CFR 151.2030 states
“For organisms greater
than or equal to
50 micrometers in
minimum dimension:
Discharge must include
fewer than 10 organisms
per cubic meter of ballast
water”
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ETV vs. G8: Land-based Tests
ETV G8
Test Cycles
3 Valid Test Cycles at each salinity
(USCG requires 5 consecutive, valid and
successful Test Cycles)
2 Test Cycles each with different
salinity (Δ10 PSU)
Test Cycle = 5 replicates
Salinity Definition
Freshwater
Brackish water
Saltwater
<1 PSU
10 – 20 PSU
28 – 36 PSU
<3 PSU
2 – 32 PSU
> 32 PSU
Challenge Conditions
DOC
POC
TSS
6 mg/l
4 mg/l
24 mg/l
Varies with Salinity
> 1 mg/ to > 5 mg/l
> 1 mg/ to > 5 mg/l
> 1 mg/ to > 50 mg/l
Sample Location
- Before Treatment
- After Treatment
- After 1 day of holding or required
treatment time
- Before Treatment
- After Treatment
- Upon discharge
Sample Volume
Organisms ≥ 50 µm
50 µm > Organisms ≥ 10 µm
Bacteria
10 m3
3 m3
1000 ml *Depends on desired precision
1 m3
10 l
500 ml
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Availability of Data
Technology Data in
TA Certificate
Data in
MEPC
Document
Land-based
Testing
Reports
Shipboard
Testing
Reports
Chlorination
(12)
5 with Land-based
and Shipboard;
1 with Land-based
Only
6 with Land-based
and Shipboard 7 6
UV (12) 3 with Land-based
and Shipboard
5 with Land-based
and Shipboard 2 2
Other (9) 2 with Land-based
and Shipboard
4 with Land-based
and Shipboard 1 1
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Example of the Data Available
Parameter Value
Salinity (PSU) 21.5 33.6 SW SW 33.1 20.7 18.7 20.6 19.9 20.2 33.46 21.43
Temperature (°C) 15.7 10.9 11.3 9.3 11.0 14.3 23.06 16
ORGANISM TYPE
≥ 50 µm ( per m3) 1.3 1 1.0 0 <1 5.3 <1 <1 <1 <1 5.0 1.8
10 - 50 µm (per ml) 0 0 0.4 0.4 <0.01 0.76 <0.01 0.03 <0.01 0.08 3.8 3.0
Hetero bacteria
(per ml) 90 0.6
Vibro cholerae
(per 100 ml) <1 <1 0 0 0 0
Enterococcus
(CFU/100 ml) <1 0 0.5 16.2 ND ND 0.35 2.3 0.21 ND 9 13
E. Coli
(CFU/100 ml) 2 0 0 0 6 23
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Key Data Issues
Confirm that influent concentrations are
above requirements
Attempt to obtain actual data – not “less
than” or “non-detect”
Obtain data for temperatures and
salinities required for ship’s operation
Photo Source: Fisheries and Oceans Canada www.dfo-mpo.gc.ca
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Final Points
Generally two types of treatment – “chlorination”
and UV
Inconsistent amount of information included in
Type Approval Certificates
Important to review data and ask vendors
questions
More publicly-available performance data are
needed
www.eagle.org