Laboratory experiments with the patented Dynaperm technology have produced flux rate increases of a factor of 50 over conventional cross flow filtration with comparable or improved effluent quality.Dynaflow says that Dynaperm is a cross-flow microfiltration concept, which utilises microporous tubes. The micron range pore size and structure can be controlled during manufacturing. The tubes, made from a variety of thermoplastics, are rugged and chemically and biologically inert. The system can also use any other commercially available microporous tubes. Dynaperm increases the flux rate and thus economy of particle removal from liquid by combining features of cyclone separation, flow interruption and cross-flow filtration resulting in greatly increased flux rates for near complete removal of suspended particles down to the micron size. Both the microporous plastic tubes and complete systems are available. Tests of particulate laden seawater conducted by Naval Facilities Engineering Service Center (NFESC) at Port Hueneme, CA, demonstrated the ability of this system to remove particulates to levels sufficient to feed to a reverse osmosis desalination system. Results of extended tests with seawater showed that the turbidity was reduced from an initial value of 2.1 NTU to a value of less than 0.1 NTU in the permeate with a decrease in silt density index from 38 (feed) to approximately 3 (permeate). Approximately 99% of the turbidity was removed even after 190h of operation. Dynaperm is claimed to be particularly effective for removal of heavy metals (for example, copper, zinc and lead).
