Generation of Liquid Waste Avoiding Entrained Water

Generation of Liquid Waste
Sources of oil/water liquids:
RECENT CASE EXAMPLES:
ITOPF Advice for Minimising Waste Generation
• Skimming at sea, near shore
• Pumping from flooded vessels
• Run-off from shoreline cleaning
Michael O’
O’Brien
Senior Technical Advisor
Key considerations:
• Keep quantities as low as possible
• Keep liquids free of debris
Decanting
Decant immediately, otherwise, virtually
impossible at later stages
• Draining out entrained water
• Significant part of recovered
liquid can be water
• Water inevitable, some added on
purpose (injection)
• Can be done from any container
with outlet at bottom
• More and more difficult with new
environmental laws
• Earlier and closer is better
Tanker used for liquid waste storage
Avoiding Entrained Water
Successful recovery and decanting operation:
200m3 oil recovered after decanting
SelfSelf-sufficient skimming vessel with
sweep arms & weir skimmer,
designed to take in oil & water together
Belt skimming system
designed to take in oil with little water
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Filtering debris from recovered oil
Debris and Vacuum Recovery
• Slops vs. hazardous waste
• Pumpability
• Closed-vs. open-top storage
• Avoid damage to filters and
pumps
Vacuum recovery can be
practical, but once debris is
taken in, it is difficult to remove
Filtering Debris
from Oil
• Difficult to filter
on site
• One exceptional
effort shown here
Generation of Solid Waste
Sources of solid wastes:
• Contaminated beach material (e.g. sand, stone)
• Contaminated debris (e.g. rubbish, algae, driftwood)
• Used sorbent material (e.g. boom, pads…)
• Worn-out equipment (e.g. inflatable boom)
Key ITOPF considerations:
• Keep quantities as low as possible
• Segregate debris
• Plan for the shifting of solid waste
Keep quantities low:
Keep quantities low:
Constant guidance & monitoring required
Target the heavy oil
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Keep quantities low:
A good start to bulk cleaning…
cleaning…
Utilise surf washing
Assisted surf
washing
Photos by Bernard Fichaut
A disastrous next step…
step…
Manual recovery of bulk:
• Average 100 men/day
• First 8 days: 125MT sludge
= 150kg sludge/man/day
Æ Not too much
Æ Not too little
Keep quantities low:
Flush the oil, then filter it out
Bulk removal of stained rock:
• First 5 days: 2500MT rock
= 500MT rock/day
Æ Far too much
Æ 32 x more/day than manual
Excessive removal of nearlynearly-clean sand
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Keep quantities low:
CoinCoin-sized HFO tar balls
Avoid using too much boom
Keep quantities low:
Take advantage of winter storms
Sorbent Boom (>15 km)
Keep Quantities low
• Don’t over-use boom
Keep waste quantities low by avoiding booming:
1) at great distance,
2) resources insensitive to oil
3) in ways that damage boom
Shifting Waste from Site:
Shifting Waste
from Site
Plan for transport and temporary storage ‘containers’
containers’
OverOver-filled, splitting, piled bags
Removal greatly facilitated if:
1) bags only filled to 1010-15kg
2) strong bags used
3) bags placed orderly
“Heavy-lift”
“Jumbo” bags
“Big bags”
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Shifting Waste from Site:
If road access is available, use heavy equipment to carry weight
Shifting Waste from Site:
If no road access, limit weight by keeping waste in small
packages
Small plastic bags
loaded into ‘big bags’
bags’
inside landing craft
Shifting Waste from Site:
Use of a crane vessel to shorten transit time
Shifting Waste
Efficiently/ cleanly packed waste:
Æ easy temporary storage
Æ nonnon-controversial storage
Æ easy shipping to final disposal
Temporary storage
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