Oil Adsorption

Natural and highly efficient oil sorbent material.

Woolspill™, a natural wool product, is an effective and highly efficient oil sorbent material able to adsorb up to 36 times its own weight in oil.

Woolspill has the following advantages:

  • Woolspill utilises the natural affinity of wool for oil adsorption.
  • Woolspill has been independently evaluated to be the best performing natural sorbent available (S.L. Ross – Environment Research Ltd, for Environment Canada).
  • Woolspill is effective for all hydrocarbon types, particularly high viscosity oils.
  • Woolspill is biodegradable.
  • Woolspill is available in a number of versatile forms permitting tailoring of oil filtration and clean-up solutions.
  • A continuous filtration system has been developed to effectively remove total petroleum hydrocarbons (to 5 ppm), suspended solids and heavy metals. These machines have been successfully applied to many industries.
  • A gravity fed system, capable of handling virtually unlimited water flows has been developed. A feature of the system is its flow rate dependence on only the capacity of the pipe work. A system has been commissioned at Auckland International Airport to treat stormwater runoff from the aircraft arrival and departure gates.

Hydro-Carbon Filtration & Separation offers solutions to remove efficiently free and slightly emulsified oil from water. The Woolspill is used as final stage in our oil-water separators or used in stand-alone pressure vessels according your requirements. Depending on the application tailor made solutions for the removal of oil, suspended solids and other contamination can be made available.

Frequently asked questions

Can knobs be used loosely?
Yes, in fact knobs in loose form will pick up oil more quickly than when constrained in a containment system.

Are Woolspill knobs flame resistant?
Yes, wool by itself does not support combustion. However, if saturated in oil they would probably burn.

If knobs are left wet in a confined area, will they spontaneously combust?
They will decompose and compost but are very unlikely to combust. Only very highly compacted high density baled wool in certain conditions has been known to combust. Woolspill is at the very opposite end, being bulky and of very low density.

Is the outer containment fabric biodegradable?
No, however it is photo-degradable, ie. it will break down due to UV degradation over a period of 5 to 6 years.

Does the fiber diameter and type of wool affect the oil pick-up?
Yes, fiber diameter affects the process of Woolspill knob formation as does the type of wool. Coarse, short fiber wool’s are much more suited and gives better average oil pick-up results than fine wool’s.

Do different sizes of knobs affect oil pick-up?
Yes, very small knobs perform better with low viscosity oils, large knobs perform better with high viscosity oils. We have chosen one product which sits towards the end of the scale depicting higher viscosity oil pick-up, as low viscosity oils tend to ‘flash-off quite quickly leaving the larger ‘molecular fractions’ behind. This residue forms high viscosity oil, which is easily adsorbed by Woolspill.

Why is Woolspill referred to as ‘adsorbing’ rather than absorbing oil?
The nature of a wool fiber is that it has ‘scales’. These are designed in nature to trap natural ‘lanolin’ oil excreted by the sheep yielding water repellency and insulation when cold. However in warm conditions they will release the oil, allowing some moisture to be held for a cooling effect. Woolspill capitalizes on this by forming the fibers into spheres with larger surface areas than normal wool making ‘adsorption’ or trapping of oil much more pronounced. Many competitive products ‘adsorb’, i.e. work on a blotting paper effect and actually allow the oil to soak into the fibre. With wool that does not happen, it only traps the oil.

Is there any advantage gained from this adsorption?
Yes, because Woolspill ‘adsorbs’ or traps oil, it is easier to recycle as it releases the oil more quickly under pressure or in centrifuges used to extract the oil.

Will Woolspill picks up paint?
Only if it is oil based. It will not pick up water-based acrylics on water.

Will wool in other forms picks up oil?
Yes it will, but not as efficiently as wool in the special knob material due to the large surface area effects. Raw wool can pick up approximately 8 times its weight Woolspill knobs close to 36 times their weight.

Does Woolspill need special protection or storage?
No, Woolspill doesn’t need special protection or storage.

In need of advice?

We welcome any request for your specific filter element needs. We will assist in the selection of the most efficient and economical solution.