patents+technologies Commercialization of innovative classifier Following the signing of a commercialization agreement, a unique particle classification technology is set to be scaled up into a continuous system. Developed by scientists at the Commonwealth Scientific and Industrial Research Organization (CSIRO) of Austalia, the rotary classifier is being described as a machine that will revolutionize particle classification in applications, ranging from mining to recycling. The major advantage of the technology is that overcomes the major problem of blinding, where material jams the holes of industrial screens and effectively reduces the screen's operating surface. It is also said to eliminate the problems associated with the constant wear-and-tear on screens from abrasive granular material. The device comprises a rotary longitudinal tube with a fixed endplate functioning as an output for the device, with holes for extracting particles from the tube. The holes are placed at different radial positions depending on the desired sizes of particulate material to be extracted. One or several sized fractions can be removed simultaneously. According to the scientists, trials using a prototype showed that building sand could be quickly and accurately separated, i.e. classified was completed after three revolutions at 2 rpm. The rights to develop the classifier technology in the field of mineral processing, quarrying rock and sand industries have been awarded to RCR Tomlinson Ltd, a engineering services company based in Perth, Western Australia. The commercialization
contract provides for a fast-track development of the classifying technology into industrial-scale applications. CSIRO's rotary classifier will be marketed as an alternative to vibrating screens for the classification of mined ore and other materials of interest to the mining industry. RCR Tomlinson hopes to have a pilot plant up and running within two years. In addition the agreement enables the company to manufacture and sell the classifier alongside its apron feeder and scrubber products.
Advancing the HEPA filter concept A new air filtration device has been developed in France for guarding against indoor air pollution, which combines high efficiency particulate air (HEPA) filtration with liquid electrostatic scrubbing capabilities. The patented filter system uses an electro-hydrodynamic atomization process to generate sprays of electrically charged demineralized water droplets. These droplets function as collectors, so any airborne microscopic particles (both neutral and electrically charged) passing through the sprays are effectively removed. This advanced HEPA filter is capable of removing sub-micron pollutant particles up to 0.1 µm in size, with a minimum efficiency of 99%. Such a performance can be achieved at an aerosol flow rate of up to 1 m3/h. In comparison to traditional HEPA filters, the new combined air filtration system, not only offers longer operating periods, but also less maintenance.
New biomass technology for MTBE removal A joint project between the University of Cincinnati, USA, and the Cincinnati office of the US Environmental Protection Agency (EPA) has resulted in the development of a system that can be used to remove gasoline contamination from drinking water sources. Conventional wastewater treatment systems, which employ aeration and solids-settling cannot remove methyl tertiary butyl ether (MTBE), a suspected carcinogen. A five-year research work has now developed a ‘biomass concentrator reactor’, which can remove or ‘scrub’ MTBE from water. To be able to remove MTBE, scientists had to create a reactor that retained as much biomass as possible during the filtering process. Biomass is the population of living organisms that function to clean the water. To retain the biomass, a porous membrane was added. This keeps the biomass in place, will at the same time allows the clean water permeate to pass through. The concept worked well on a small scale, so the reactor was scaledup to increase the volume of liquid flowing through the device. According to the researchers, good results were achieved, regardless of the influent concentration of MTBE and whether there were other contaminating carbon sources present in the water. A full-scale prototype is due to be installed in Pascoag, Rhode Island, USA, over the summer, in an effort to remove a MTBE, which had leaked from underground gas tanks into the communities’s ground water supply.
Patent Summaries Vapour Deposition Treated Electret Filter Media, Hollingsworth & Vose Co, USA. WO 02/076576. Date of Publication: 03 October 2002.
Method and Installation for Regenerating Absorbents used for Capturing Sulphur Dioxide in Combustion Fumes, Institut Francais du Petrole, France. WO 02/087755. Date of Publication: 07 November 2002.
Screen Centrifuge, HeinkelAktiengesellschaft, Germany. WO 02/078852. Date of Publication: 10 October 2002.
Process for Regenerating a Filtration Cartridge for Filtering a Slurry, Mykrolis Corp, USA. WO 02/089951. Date of Publication: 14 November 2002.
A Combination Filter for Filtering Fluids, 3M Innovative Properties Co, USA. WO 02/081061. Date of Publication: 17 October 2002.
Porous Ceramic Sintered Body and Method of Producing the Same, and Diesel Particulate Filter, Ibiden Co Ltd, Japan. WO 02/096827. Date of Publication: 05 December 2002.