DETERMINATION OF EFFICIENT RECOVERY METHODS BASED ON NATURE OF SPILLED OIL

PRESENTED BY: GOWTHAM RAJAGOPAL RAHULNATH R

ASSO.PROF SAVIN VISWANATHAN

PROF SATHEESH BABU PKDepartment of Naval Architecture & Ship Building

SNGCE

ABSTRACT

THIS RESEARCH PAPER FOCUSSES ON OCCURANCE OF MAJOR OIL SPILLS AND ITS

EFFECTS ON MARINE ECOSYSTEM PRESENT TECHNOLOGIES TO TACKLE OIL

SPILLS THE MOST EFFICINT MEASURES TAKEN TO

REMOVE SPILLED OIL AT SEAS

OIL SPILLS ??

Oil Spill is accidental or intentional release of liquid petroleum hydrocarbon into the ocean or coastal waters due to human activity mainly.

CAUSES OF OIL SPILL Sinking or leakage of Oil carrying vessels

or Oil pipelines Illegal dumping by industries Countries at war Terrorist activities Natural Disasters

ENVIRONMENTAL EFFECTS OF OIL SPILL

EFFECTS ON MARINE LIFE FISH

Eye cataracts Structural changes of fins Loss of body weight

Marine mammals

Marine plants

Birds

Plankton

Plankton are small plants and animals that live in the water

Plankton are important because they are at the bottom of the aquatic food chain.

oil ingested or absorbed by plankton is passed higher up the food chain, until it is finally ingested by fish and mammals.

INTERTIDAL FAUNA Intertidal fauna include animals that live in the shoreline zone

between the high and low tides. Most vulnerable to oil spills because they and their habitat are

frequently coated during oil spills. Heavy oiling will generally kill most species

METHODS OF PRESENT CLEAN UP Surface dispersants

Advantage: The chemicals can be sprayed over a large area within a short time thus enabling to reduce the toxic effects of oil spill .Disadvantage: The chemical dispersant itself getting toxic in addition to the toxic fuels being spilled

Underwater dispersantsAdvantage: The oil can be decomposed to smaller droplets even before they reach the surface.Disadvantage: The underwater dispersant may give out toxic substance during decomposition .Also the use of an underwater vessel at extreme depth is not possible. Manual cleanup

Advantage: Little skill and training is required to clean up the shore and with more machinery, the process can be done at a faster rate.Disadvantage: The use of machinery in excess can lead to destruction of biodiversity in the shores. Also, this technique doesn't prevent the oil from spreading into the shore

Controlled burns

The spilled oil is contained using a fireproof boom and the oil is set to fire in a controlled manner

Advantage: The oil is removed quickly from the surface of water.Disadvantage: The toxic smoke coming out from the fire causes harmful air pollution

Bioremediation

• It’s the action of bacteria which decomposes the oil• By increasing the amount of bacteria, rate of decomposition can be

increased• For increasing the bacterial rate, sulfate or nitrate fertilizers are

added

Advantage: This method doesn't affect the biodiversity much as it doesn't add any chemicals to the environment and the whole thing works naturally. Cost effective and safe.Disadvantage: It is a slow process.

Gelling agentsThese are chemicals that solidify the oil into rubber like material which float on water and can be removed using nets, skimmers etc.Advantage: Easy to use after a spill with less time required for deployment.Disadvantage: The amount needed is very high

Centrifugal oil water separatorMode of Operation: A mix of oil and water is pumped constantly into a cone shaped apparatus at an angle, which creates a spinning vortex.Advantage: low cost of operation, versatility and efficiency .Disadvantage: To cleanup sea water using this method takes time as it has limited capacity to handle seawater

DETERMINATION OF OIL SPILL CLEANUP METHOD BASED ON SPILLED OIL

Factors affecting Oil spill Clean-up• Quantity of spillage• Type of oil spilled• Weather conditions• Time of response

Classification of Oil

Oil Type

Intermediate Fuel Oil

Bunker Fuel Oil

Gasoline

Diesel fuelLight Crude Oil

Heavy Crude Oil

Crude Oil Emulsion

CHARACTERISTICS OF OIL THAT AFFECT SPILL

• Viscosity• Density • Solubility in water• Interfacial Tension

WEATHERING

Change in characteristics of oil once it get spilled into water.

Characteristics of Weathering

1. Rate is maximum just after the occurrence of spill and rate changes gradually

2. Temperature dependent 3. Depend on oil type

Important weathering process:• Evaporation • Emulsification

Important change after weathering• Density change• Viscosity change• Flashpoint change

Evaporation

• Most important weathering process• Depend on volatility of components in oil• Less dependent on wind and surface area

Evaporation rate during a time period of 48 hours after spill at 15O C

Highly depended upon the constituents making up the oil.

Emulsification

Process by which one liquid is dispersed into another one in the form of small droplets

The response time after an occurrence of oil spill is crucial in order to restrict weathering process

EFFECT OF DIFFERENT METHODS OF CLEAN UP ON DIFFERENT OIL

Skimmer

• Mechanical removal of oil from the surface of water• Most effective when the oil is contained with the help of

boom• Skimmers are classified according to the area of

application such as Offshore, Onshore ,shallow etc

Recovery rate in cubic meter per hour

• When different oils are compared ,Heavy crude oil is most recovered ,followed by light crude oil and Bunker C oil. Diesel comes at last.

• Recovery rate is also determined by weather conditions present at the time of recovery.

Dispersants

These are chemical compounds that help to break the oil film on water.

Effectiveness of dispersant are determined by• Composition and weathering of oil• Amount and type of dispersant applied• Sea Energy• Salinity• Temperature

The effectiveness of dispersant during High energy and Low Energy seas were studied and following were found.

• Diesel is easily broken down by dispersant followed by light crude oil and heavy crude oil. Bunker C oil comes at last

• Effectiveness is high in High Energy conditions

Sorbents

• Materials which absorb oil either through adsorption or absorption• They absorb both oil and water.• High recovery rate is needed for effectiveness• Care must be taken to prevent sinking of sorbents after use.• Recovery rate depend mainly on oil type and surface type

Study was conducted on the recovery of oil using synthetic sorbents

• Heavy Crude Oil is easily recovered followed by Light Crude oil and Diesel. Bunker C oil comes last in recovery

FINDINGS ON THE BEST SUITED METHOD FOR EACH OIL

• The study was conducted mainly on the above given clean up methods• Other methods are still inferior to these or cause environmental problems while clean-

up and hence avoided

• When diesel is spilled the best suited clean up method is the use of Surface Dispersant.

• For Heavy Crude Oil and Light Crude Oil the best suited clean up method is the skimmer.

• Bunker C Oil is found to be recovered most effectively by sorbents.

Oil Best Cleanup methodDiesel Surface DispersantHeavy Crude Oil SkimmerLight Crude Oil SkimmerBunker C Oil Sorbents

FUTURE CLEAN UP METHODS

• The existing methods for clean-up are either outdated or do not meet the environmental standards .

• Researches are conducted all over the globe for innovative clean-up methods for future needs

1) Grooved Disc Skimmer Technology

This is an improvement made to existing skimmers with grooved discs used for skimming

Surface area increase result in manifold increase in recovery rate

Grooved skimmers manufactured by company named ELASTEC have water to oil efficiency of over 89.5%

This is one of the most promising innovation for clean up in the future with wide application with different configuration.

No environmental harm

2) MAGNETIC SEPARATION USING NANOTECHNOLOGY

• Uses magnetic nanoparticles and magnetic field to separate oil from water.

• The nanoparticles are coated with surfactants which are hydrophobic and lyophilic

• Hence easy separation using magnetic field to collect nanoparticles along with oil

3) BASALT FIBER TECHNOLOGY

• Obtained from basalt rocks • Basalt rocks are melted and extruded

through small openings to produce Basalt fibre

• Fibre is lyophilic and hydrophobic • Fibres absorb oil up to 75 times its own

weight

4) MICROBES

• Microbes are genetically modified to eat up spilled oil.

• Microbes are modified to die off after the oil is eaten up.

• No environmental harm after clean-up

5)SWARM ROBOTIC SYSTEM

• Swarm robotics is a field of multi-robotics in which large number of robots are coordinated in a distributed and decentralised way.

• Large number of robots can be fitted with clean-up technologies

• Clean a vast area with large number of robots coordinated from a remote area

• Highly mobile and easily deployable

6) SPONGES

• Designed to absorb only oil and hydrophobic• Working similar to that of a normal sponge• Able to absorb oil up to 50 times its weight

and still float in water• Boom arrangement coupled with sponge

system to ensure maximum absorption and effectiveness

CONCLUSION

Recovery of oil from seas is a mandatory process. Even though there are a lot of recovering methods till date we should improve our methods in the path of an effective and efficient scenario. As our history reveals us the fact that most of the oil spill situations were ended with worse conditions just because of ineffective recovery methods. This may due to the behavior of oil towards different recovery systems. This area should be focused and we have to make use of the best recovery method which suits for the nature of the oil.

REFERENCES• D.R. Visits, S. Nieto-Roman, A. Palanca, X. Ferrer,M. Vences, European Atlantic: the hottest oil spill hotspot

worldwide, Naturwissenschaften 91(2004) 535–538. • GESAMP, Estimates of oil entering the marine environment from sea-based activities, in: GESAMP Reports

and Studies 75th, International Maritime Organization, London, UK, 2006.• ITOPF, Tanker Oil Spill Statistics: Report on the Activities of the International Oil Pollution Compensation

Funds in 1999, the International Tanker Owners Pollution Federation Ltd., 2000.• Merv Fingas. (2000,May 10) Basics of oil spill cleanup. (2nded.)[Online]. Available:

https://www.crcpress.com/The-Basics-of-Oil-Spill-Cleanup-Second-Edition/Fingas-Fingas/9781566705370•  • http://www.cnbc.com/2010/06/09/17-Ways-To-Clean-Up-The-Gulf-Oil-Spill.html• Skimmer(machine)Available: https://en.wikipedia.org/wiki/Skimmer_(machine)• Sorbents http://www2.epa.gov/emergency-response/sorbents• 5 Innovative Solutions That Clean Up Oil Spills. http://inhabitat.com/top-5-green-ways-to-clean-up-oil-spills/• Slick Solution: How Microbes Will Clean Up the Deepwater Horizon Oil Spill.

http://www.scientificamerican.com/article/how-microbes-clean-up-oil-spills/• Gelling Agents. http://www2.epa.gov/emergency-response/gelling-agents• Centrifugal-water oil separator. https://en.wikipedia.org/wiki/Centrifugal_water%E2%80%93oil_separator• How do you clean up oil spill? http://science.howstuffworks.com/environmental/green-science/cleaning-oil-

spill1.html• Grooved Disc Technology http://elastec.com/oilspill/oildrumskimmers/groovedisc/• How to cleanup oil spills. http://news.mit.edu/2012/how-to-clean-up-oil-spills-0912• Basalt Fiber. https://en.wikipedia.org/wiki/Basalt_fiber• Basalt Fiber: Future of oil recovery? http://eandt.theiet.org/magazine/2013/06/clean-tech-gets-slick.cfm• 3 Future Oil spill fighters. http://news.nationalgeographic.com/news/2010/05/100511-science-environment-

gulf-oil-spill-cleanup-future/• Will robots cleanup oil spill? http://green.blogs.nytimes.com/2010/08/24/will-robotss-clean-up-future-oil-

spills/?_r=0• Sponges would clean up oil spills http://www.swissinfo.ch/eng/deepwater-horizon_sponge-could-clean-up-

future-oil-spills/41379404

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