Filtration and Water Reuse

In a resource limited world every opportunity for recovery of resources will become increasingly important. The opportunities exist for substantial saving of water resources and operational expenses by recovering wastewater and reclaiming it for further use. Dynaflow Inc. is using its knowledge of hydrodynamics and cavitation to help you capitalize on these opportunities..

Filtration using DynaPerm ® Enhanced Cross Filtration

The DynaPerm ® filtration system uses cross-flow micro filtration concept which utilizes thick-walled micro porous plastic tubes. DynaPerm ® combines features of cyclone separation, flow interruption and cross-flow filtration to maintain higher flux rates and extend operation time between cleanings. Automated flow interruption and membrane back flushing are used to clean the filtering tubes without requiring operator intervention. Filtration tubes are available in either polyethylene with 65% porosity and equivalent pore diameters of 3 – 9 µm, 80% porosity and 1 – 8 µm equivalent pore diameters, or nylon, 65% porosity, 1 – 2.5 µm.

The DynaPerm ® filtration system was recently used to recover paint overspray from water mist overspray booths down to less than 0.2 parts per million solids. These systems have also been used to remove heavy metal particles and paint chips from water jet paint removal operations.

 Permeate flux rate for paint waste with 280 and 290 mg/L paint

Oxidation of Trace Organic Compounds using DYNAJETS® Submerged Cavitating Jets

The DynaJets ® can be used to remove recalcitrant pollutants from prior to water reuse. Hydrodynamic cavitation has been shown to oxidize volatile and hydrophobic compounds in water. A an example, Figure 3shows data of the removal of the pharmaceutical ibuprofen; the antibacterials, chloroxylenol, and triclosan: the fragrance compounds, galaxolide, musk ketone; oxybenzone a sunscreen, and tris-(2-chloroethyl) phosphate, a plasticizer from wastewater treatment plant effluent. These compounds are often found in treated effluent and have been reported in reclaimed water [2]. The effluent samples were oxidized using a DynaSwirl ® nozzle at low pump pressures. In Figure 1 the log octanol-water coefficients (log KOW), for each of the seven compounds are inset on the table. The higher the log KOW the more hydrophobic the compounds is. A can be seen the more hydrophobic compounds were removed faster in the wastewater matrix than were the more hydrophilic compounds.

 Removal of a mixture of 7 pharmaceuticals, personal-care-products and other organic pollutants, from wastewater treatment plant effluent using a DynaSwirl® nozzle.