Reed bed

Gravity separation Centrifugal separation Filtration Membrane filtration Coalescence Centrifugal separation Flotation Wet oxidation Thermal oxidation Biological oxidation (aerobic, anaerobic, reed beds) Chemical oxidation Activated carbon Wet oxidation Thermal oxidation... 

Engineered reed-bed and constructed wetland systems for removal of heavy metals from wastewater using phytoremediation are in use in some developed Asian countries. The root system of the hyper-accumulator plant penetrates a permeable rock bed. The wastewater is introduced into one end of the bed and flows through the permeable rock layer. The rock layer should be inert to heavy metals binding so that it does not unwittingly serve as a sink for heavy metals. These metals are sequestered by the root system and translocated to the shoots. Periodically, the metal-containing shoots are harvested. The biomass can be burned off or composted to yield a low volume of metal-rich ash. 

Mud samples were taken from a reed bed near the Ballarat goldfields in Ballarat, Victoria, Australia, for the purpose of isolating an arsenate-respiring bacterium... 

Three of the most commonly used biological processes are the aerated lagoon, the rotating biological contactor and the vegetated ditch (or reed bed). 

Robinson, H.D., Barr, M.J., Formby, R. and Morag, A. (1993) Using reed bed systems to treat landfill leachate. Wastes Management Proceedings, April, 20-26. Rovers, F.A., Tremblay, J.J. and Mooij, H. (1978) Procedures for landfill gas monitoring and control. Waste management report EPS 4-EC-77-4on the Proc. International Seminar Fisheries and Environment. Minister of Sui ly and Services, Montreal, Canada... 

Temple columns were embodiments of the Nile reed beds and hunting grounds, the ancient Egyptians idea of paradise on earth. There was no incentive to abstract the columns, made by bruising down the stone with diorite, to minimal cylindrical shafts. 

The contributions in this volume also demonstrate that chemical barriers may, in certain cases (notably in the management of contaminated land and mine wastes), prove easier to deploy than physical barriers. An example is the application of reed beds to clean mine waste. Such cases are permeable active containments. At the opposite end of the spectrum, it is possible to rely mainly on physical containment. This strategy is most appropriate where it is difficult to demonstrate convincingly that a chemical barrier will exist over the time span for which the disposal site must remain isolated. 

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