OPRC Level 1 Use of Absorbing Materials Version Νο.1 12.05.2013
Aim Use of absorbent materials to recover low viscosity oils and remove leaching oil from the environment
The Use of Sorbent Materials Sorbent Materials Are Usually The First & The Last Response To Most Spilt Liquid Products Both Large & Small
Outline Materials able to absorb oil (sorbents) Common types of absorbing products Use of natural vegetation and locally available absorbing materials
Sorbent Functions Absorb oil oil penetrates into the sorbent Adsorb oil oil is attracted to the surface of the sorbent only
Required Properties of Sorbents Sorbents should be: o Oleophilic attract oil o Hydrophobic repel water Sorbent properties: o Absorb large amount of oil & very little water o Must not sink when absorbed oil o Be strong enough to be recovered
Required Properties of Sorbents Sorbents should be: o Oleophilic attract oil o Hydrophobic repel water Sorbent properties: o Absorb large amount of oil & very little water o Must not sink when absorbed oil o Be strong enough to be recovered
They are Simple They are flexible
They are not just for small spills
Materials Able to Absorb Oil Organic material Inorganic material Synthetic material
Organic Material Straw Peat Sawdust Chicken feathers Ground corn cobs Carbon products
Straw bale being used as a first response to a diesel spill
Qualities of Organic Materials Advantages Normally available in large quantities Absorption capacity is often good but varies according to material; can be 5-15 times their weight of oil Disadvantages Some products absorb water and will sink Granulated products can pose problems: keep material in netting
Inorganic Material Vermiculite Snow
These are the impact sites from two aircraft that crashed in the Scottish Highlands releasing aviation fuel and hydraulic oil into the very sensitive snow covered environment some 3500ft up
Contaminated snow in a plastic lined one cube lift bag
250 one cube bags full of heavily contaminated snow were airlifted from the site
Some of the hydrocarbons had started migrating downhill beneath the snow. Using GPS & OS maps the route of the streams are excavated and synthetic sorbents placed to intercept any oil reaching them during the spring melt
Qualities of Inorganic Material Advantages Absorb large quantities of oil: 4-20 times their own weight Normally cheap Disadvantages Can be difficult to apply blown by wind Unpleasant to inhale Non-biodegradable
Synthetic Material Polyurethane Polyethylene Polypropylene Nylon fibres Urea formaldehyde foam
A 5 diam. Polypropylene sorbent boom being used to CONTAIN and RECOVER LIGHT hydrocarbons from the surface of a stream
Source:OSRL
Qualities of Synthetic Materials Advantages Highly oleophilic and hydrophobic High absorption rates: 25+ own weight May be re-used Pore size control allows viscous oil recovery Disadvantages Not always available in large quantities Reduced efficiency of oiled sorbents Relatively expensive
Specific Absorbent Products Rolls, sheets, blankets, pads Loose (granulate) Enclosed (pillows, booms) Agglomeration units (open netting or pore foam highly viscous oil) Pom poms
Sorbent booms without skirt Sorbent booms with skirt Beach Carpet
Sorbent Boom
The spaghetti sausages were from the Whitegate refinery spill, Ireland, 1997
Natural Vegetation Bundles of straw Bundles of grass
Straw or any long fibre vegetation that can be secured to prevent loss
Advantages of Using Sorbents Can help to remove last sheen of oil o cost benefit is a consideration Recover very little water Light and easy to handle before use
Disadvantages of Using Sorbents Can be very heavy and difficult to recover when soaked with oil Recovery of granulates and pads may be difficult Freely floating sorbent material may get into pumps and skimmers