Herbert Engineering Corp.

ugliestmysticΤεχνίτη Νοημοσύνη και Ρομποτική

14 Νοε 2013 (πριν από 4 χρόνια και 1 μήνα)

80 εμφανίσεις

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

California
1,2

IMO Regulation D
-
2
1

Washington

Organisms greater than 50 µm in
minimum dimension

No detectable living
organisms

< 10 viable organisms per
cubic meter

Technology to
inactivate or
remove:

95% zooplankton

99% bacteria and
phytoplankton

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


Escherichia coli

Intestinal
enterococci

Toxicogenic

Vibrio

cholerae

(01
& 0139)

< 10
3

bacteria/100 ml

< 10
4
viruses/100 ml


< 126 cfu
3
/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 Bal
la
st Water
Performance Standard

[2]

Final discharge standard for California, beginning January 1, 2020, is zero detectable living organisms for all organism size

c
lasses

[3]

Colony
-
forming
-
unit

Implementation Schedule for Performance Standards













(Ref. Dobroski, ‘Aquatic Invasive Species and Ballast Water Management’)

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

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

+ H
2
O + 2e
NaOCl

+ H
2


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



5000 m3/hr




$100k to $400k

$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

California
1,2

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


Escherichia coli

Intestinal
enterococci

Toxicogenic

Vibrio

cholerae

(01 & 0139)

< 10
3

bacteria/100 ml

< 10
4
viruses/100 ml


< 126 cfu
3
/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.