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Extended Applications

The purpose of this page is to give exposure to commercial applications of our dry-liquid blends that are not currently covered by non-disclosure agreements.

PMPS Particles in Porous Pavement Systems

Porous pavement systems (PPS) are man-made porous surfaces used to attenuate storm water run-off to reduce discharge to sewers and water courses, allowing for sedimentation, filtration and trapping of pollutants. They are designed to simulate the action of natural surfaces and their drainage characteristics.

PPS also treat the water that contains heavy metals, high levels of suspended solids and oil, and other hydrocarbons. One type of layered PPS consists of concrete block paving that is either porous or has infiltration pores, a bedding layer of gravel and a geotextile layer which separates the blocks from the sub-base layer of granite that acts as a water reservoir. These structures successfully allow the sedimentation of solids and the retention of pollutants.

Oil degrading micro-organisms feed on the retained oil and bio-degrade it, which primarily occurs on the first geo-textile layer that acts as a support for the organisms. Hydrocarbon-degrading micro-organisms commonly occur in the terrestrial environment and so are present upon the recycled gravel and granite materials used in the PPS. The extent of oil biodegradation by these organisms is limited by the availability of nutrient (particularly phosphorus) in their surrounding environment. 

PMPS Particles absorb aqueous ammonium phosphate solution. These phosphate loaded particles can be incorporated as an additive to polymer fibres that are then spun into the geotextile matting. The release rates of phosphorus achieved by ‘doping’ the geotextile with ammonium phosphated μ-Sq beads is at a suitable level to sustain the bacteria and not cause eutrification of phosphorus into the ground water.

Cross-section of a Porous Pavement System (left) and bacterial growth over the doped geotextile (right)

porus pavement image

Publications:

Gillian E. Spicer, Daniel E. Lynch, Alan P. Newman and Stephen J. Coupe, "The development of geotextiles incorporating slow-release phosphate beads for the maintenance of oil degrading bacteria in permeable pavements", Water Sci. and Tech., 2006, 54, 273-280.

 

 

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