Certain liquids, such as wine, are sensitive to contact with oxygen and may be degraded by oxidation, so winemakers usually take steps to limit or entirely prevent oxygen from contacting the wine. For example, inert gases may be used to displace oxygen. In reductive winemaking processes, oxygen is
Biofiltration is the filtration of contaminated water using organic material to capture and biologically degrade contaminants. A biofilter comprises inorganic or organic filtering media such as rock, slag, sand, glass beads, peat or wood chips on which a biofilm develops when wastewater flows over

The Cleancolytic Reactor System developed at the Cape Peninsula University of Technology is a one-step waste water treatment system consisting of highly reactive nanoparticles immobilized in a specialised reactor system for the purpose of treating industrial wastewater. The system utilizes a