Transcript Newsletter
Spencer Schilling
President
Herbert Engineering Corp.
Overview
Shipboard Ballast Operations
Typical Ballast System Components
AIS and Ballast Water
Shipboard Ballast Water Management Solutions
Exchange
Treatment
Treatment Technologies : Engineering Challenges
Shipboard Ballast Operations
Why is ballast used?
Maintain seaworthy
condition when lightly
loaded
Draft, trim, stability,
bending moment, shear
force, slamming,
propeller immersion,
motions
Shipboard Ballast Operations
How is it handled?
Loading condition is assessed and ballast allocated to
remain within safe operational limits
Ballast movements coordinated with cargo operations
Impact on Crew
Provides for vessel safety
Controls vessel motion for better comfort
Requires daily management of ballast and maintenance
of systems and tanks
Typical Ballast System Components
Simple liquid storage/handling system
Tanks, piping, valves, pumps
Vents, overflows, sounding tubes, level indicators
Remotely operated
Sea chests and overboard discharges
Ballast System – Design
Considerations
Total ballast volume – 6,000 to >100,000 m3
Flow rates – 200 to 5000 m3/hr
Head requirements – up to 30m
In service flexibility (# tks, pipe, valves, …)
Ballast Exchange Options
Partial Ballast Conditions
Control systems
What are AIS?
Aquatic Invasive Species (AIS) are
organisms transported by human
activities to a region where they did not
occur historically and have established
reproducing populations in the wild.
(Ref. Dobroski, ‘Aquatic Invasive Species and Ballast Water Management’)
How do we manage AIS?
Prevention – Best line of defense, vector
management
Eradication – Costly and often
impossible, over $6 million to
eradicate Caulerpa (algae) from
two small southern CA
embayments
Species management once established – restrict
local movement, control populations in sensitive
habitats if possible
(Ref. Dobroski, ‘Aquatic Invasive Species and Ballast Water Management’)
How do they get here?
Many mechanisms (vectors) capable of transporting
AIS around the world
Aquaculture, live seafood shipments, bait, pet store
trade, intentional release
Commercial ships responsible for up to 80% of
introductions in coastal habitats
Includes ballast water and vessel fouling
(Ref. Dobroski, ‘Aquatic Invasive Species and Ballast Water Management’)
Ballast Water and AIS
Species are introduced upon ballast water discharge in
recipient regions
(Ref. Dobroski, ‘Aquatic Invasive Species and Ballast Water Management’)
Ballast Water Management Options in
California
Retain all ballast on board the vessel
Ballast water exchange
Discharge to an approved shoreside treatment facility
(currently no such facilities in CA)
Use of alternative, environmentally sound CSLC or
USCG approved method of treatment
(Ref. Dobroski, ‘Aquatic Invasive Species and Ballast Water Management’)
Ballast Water Treatment Standards
Organism Size Class
California1,2
IMO Regulation D-21
Washington
Organisms greater than 50 µm in
minimum dimension
No detectable living
organisms
< 10 viable organisms per
cubic meter
Organisms 10 – 50 µm in
minimum dimension
< 0.01 living organisms
per ml
< 10 viable organisms per
ml
Organisms less than 10 µm in
minimum dimension
< 103 bacteria/100 ml
< 104 viruses/100 ml
Technology to
inactivate or
remove:
95% zooplankton
99% bacteria and
phytoplankton
Escherichia coli
Intestinal enterococci
Toxicogenic Vibrio cholerae (01
& 0139)
< 126 cfu3/100 ml
< 33 cfu/100 ml
< 1cfu/100 ml or
< 1cfu/gram wet weight
zoological samples
< 250 cfu/100 ml
< 100 cfu/100 ml
< 1 cfu/100 ml or
< 1 cfu/gram wet weight
zooplankton samples
[1]
See Implementation Schedule (below) for dates by which vessels must meet California Interim Performance Standards and IMO Ballast Water
Performance Standard
[2] Final discharge standard for California, beginning January 1, 2020, is zero detectable living organisms for all organism size classes
[3] Colony-forming-unit
Implementation Schedule for Performance Standards
Ballast Water Capacity of Vessel
Standards apply to new vessels in this
size class constructed on or after
Standards apply to all other vessels
in this size class beginning in
< 1500 metric tons
2009
2016
< 1500 – 5000 metric tons
2009
2014
> 5000 metric tons
2012
2016
(Ref. Dobroski, ‘Aquatic Invasive Species and Ballast Water Management’)
Treatment Technology Challenge
Achieve desired kill rate
Work at high flow rates and with large volumes
Work with water of varying salinity, temperature,
nutrients, clarity
Do not introduce other personnel/environmental hazards
Provide mechanism/process for testing/monitoring
Do not disrupt ship operations/schedule
Fit in limited space and survive ship conditions (vibration,
pitch/roll motions,...)
Use available power
Do not add to ship maintenance
Be economical to buy, install, use and maintain
Treatment Technology Solutions
Chemical Biocides (“Active Substances”)
Chlorine (Generated on Board)
Ozone (Generated on Board)
Proprietary Chemicals (some delivered pre-mixed)
Mechanical Separation - Filters
Physical Change to Ballast Water Environment
Irradiate (UV light)
Deoxygenate
Heat
Chlorine
NaCl + H2O + 2e
NaOCl + H2
Generate Chlorine / Sodium Hypochlorate (bleach) with
electrolytic cells on board
Add solution when taking on ballast, maintain levels
during voyage
Lethal in hours
>80% chance can meet IMO 2004
criteria
Systems designed but limited
testing to date
High dosage levels can promote
steel corrosion
Concern about chemical residuals
Ozone
Ozone generator on board using high
voltage AC current
Applied at uptake or discharge
Lethal in 5-15 hours
Short half life limits corrosion and
makes safe at discharge
<60% chance can meet IMO 2004
criteria
Systems designed but limited testing to
date
Proprietary Chemicals
Pre-Mixed proprietary chemicals
introduced at metered dosage rate
when taking on ballast
Chemicals degrade over time,
designed to be safe at discharge
Lethal in 24 hrs
>80% chance can meet IMO 2004
criteria
Full size testing ongoing
High dosage levels can promote steel
corrosion
Concern about chemical residuals
Example
Peracetic Acid
C2H4O3
acetic acid, hydrogen
peroxide with sulfuric
acid catalyst.
Produced on shore,
delivered to ship in
chemical tanks
Mechanical Separation
Filters and Cyclones
Filters for larger organisms
Done at uptake and/or discharge
‘Lethal’ at time of treatment
<80% chance can meet IMO 2004 criteria
Full scale testing on going
Filtration with Backflush
50 microns is the practical lower limit
Automatic backflush is required to allow for
unattended operation
Backflush process reduces the net flow rate and
increases the system
pressure drops
External backflushing
pump is required
Probably not practical
for bulkers and tankers
with high flow rates
and volumes
Filtration with Backflush
Can remove most of the larger life forms
A 50 micron screen will remove most or all of the
zooplankton and some of the phytoplankton and
dinoflagellates.
Filters of a practical size are not effective against
bacteria and viruses
Useful in reducing turbidity (suspended solids)
Cyclonic Separation
figure
Cyclonic Separation
Can remove solids heavier than the sea water and
larger than about 50 microns
About 5% to 10% of the total flow rate is removed in
the sludge discharge
Pressure drop is about 0.8 bar plus backpressure valve
at 1.2 to 1.5 bar
Cyclonic Separation
Effectively remove the large vertebrates and
invertebrates
Not effective in reducing zooplankton density, but it
does reduce live densities
Not that effective in reducing bacteria, viruses, or
phytoplankton
Physical Change to Environment
Ultraviolet (UV) Light
Inactivates living organisms by causing DNA
mutations
Proven effective against zooplankton, phytoplankton,
bacteria and viruses.
Need pretreatment to reduce size of organisms and
exposure time
Can be used on intake and discharge
Ultraviolet (UV) Light
Can be automatically controlled and monitored
Long history in the marine industry and
demonstrated low maintenance requirements
Basic technology is readily available on the market
Turbid materials in the ballast flow attenuate and
scatter the UV radiation
Physical Change to Environment
Deoxygenate
Inert gas generated on board
When mixed with water, lowers Oxygen and pH
Lethal in 4 to 6 days
>80% chance can meet IMO 2004 criteria
Full scale testing on going, some systems approved by
IMO
Reduces corrosion, but can require closed tank vent
system to maintain low oxygen atmosphere.
Physical Change to Environment
Heat Treatment
Heat water to threshold temperature (42 degC)
Lethal in hours to days
Requires large amount of energy and can be difficult to
generate heat in port when ME not running
<60% chance can meet IMO 2004 Criteria
Full scale testing on going
Heat promotes corrosion
Combined Systems
Cyclonic + UV System
(courtesy Optimar/Hyde Marine)
2- Stage Treatment
Cyclonic Separator + UV
3 - Stage Treatment
Filter + UV + Chemical
50 micron filtration
remove large particles
remove sediments
UV light
inactivate living organisms
reduced efficacy with cloudy water
Catalysts
activated by UV energy producing oxidizing chemicals
increases efficacy of UV in cloudy water
Life Cycle Costs
Acquisition
250 m3/hr
$100k to $400k
5000 m3/hr
$400k to $1800k
Installation
$50k to $125k
$200k to $800k
Operating
$0.02/m3 to $0.45/m3
7000 m3
$140
$3,150
70,000 m3
$1,400
$31,500
Maintenance $ ?
Safety Issues
Handling and storage of chemicals, radiation and
other equipment meant to kill living organisms
New risks to personnel and the environment
IMO G9 Procedures considering eco-toxicology,
human health and ship and crew safety
(MEPC.126(53))
Local, State, National water quality regulations
Regulatory Compliance and Testing
Stricter standards
Testing is time consuming
Lab results may not scale
well to full size
Functional testing and
equipment certification
“Type Approval”, or
In service testing (“end of
pipe”) for continuous
monitoring
Organism Size Class
California1,2
Organisms greater than 50
µm in minimum
dimension
No detectable living
organisms
Organisms 10 – 50 µm in
minimum dimension
< 0.01 living
organisms per
ml
Organisms less than 10 µm
in minimum dimension
< 103 bacteria/100 ml
< 104 viruses/100 ml
Escherichia coli
Intestinal enterococci
Toxicogenic Vibrio cholerae
(01 & 0139)
< 126 cfu3/100 ml
< 33 cfu/100 ml
< 1cfu/100 ml or
< 1cfu/gram wet
weight
zoological
samples
Need for Engineered Solutions
Develop treatment technologies (Entrepreneur stage)
Design testing methods and process for type approval
or continuous monitoring
Automatic ballast water analyzers (bug counters)
Ship design adjustments and system integration
Regulatory development/evaluation
Spencer Schilling
President
Herbert Engineering Corp.