STRIALNEWS No-back-washfilter success Severn Water Services of Kidderminster, UK - manufacturer of the innovative DynaSand continuous sand filtration system has recently sold its 150th unit to the UK water industry. Installed at South West Water’s Ugborough Treatment Works near Plymouth, for the tertiary treatment of settled sewage effluent, it is part of Sws programme to meet the new NRA discharge limits. The filtration system, designed in Sweden and introduced to the UK by Severn in 1984/5, was used initially for industrial applications, but in the past three years an average of 50 units per year have been supplied to the water industry. One of the main advan-
tages claimed for DynaSand is the absence of backwashing, eliminating the costs of frequent attention, labour and downtime usually found with conventional filtration. The design creates an up-flow of sand and a counter-flow of water, enabling fouled sand to be continuously removed from the filter bed, washed and recycled without interruption to the filtration process. The single DynaSand at Ugborough is a DST15D model (1.4 m diameter and 5.4 m high)s with a filter area of 1.5 m . This unit also has the distinction of being part of the fastest-ever contract executed by Severn, delivered to site two weeks after receipt of order and
Fractional crystallisation for China Sulzer of Switzerland has recently received a contract to supply a naphthalene purification plant (annual capacity of 20 000 t) from the Anshan Iron & Steel Corporation in China. Careful evaluation of the plants available on the market resulted in the decision to purchase the Sulzer fractional crystallisation system. The main criteria with which the process had to comply are environmental compatibility, flexible handling, high degree of purity, automatic control, low
maintenance costs, and a long plant operating life. The Sulzer falling-film crystallisation plant complies with all these requireApplying this ments. technology, organic substances can be purified without using a solvent. The process features high separation efficiency, excellent reliability and a broad field of applications. SuLzerBrothers Ltd, CH-8401 Winterthur, Switzerland. Tel: + 41 52 262 1122, f?tx: + 41 52 262 0101.
Coalescer cartridges’ dual role Alan Cobham Engineering has supplied coalescer cartridges, for gas condensate filtration and separation for the Goodwin A Gas Production System, to Woodside Offshore Petroleum, after extensive CSIRO comparison tests. The cartridges fuhil the dual role of removal of both water and solid contamination from the gas condensate, which would otherwise cause severe problems in the delivery pipeline. With a high level of particle conFiltration & Separation
tamination and low viscosity of condensate, a special design was necessary to remove the critical solids above 5 micron, and to achieve a residual water contamination of typically 5 ppm. Long service life was another particular requirement that had to be provided. Alan Cobham Ltd, Holland ford Forum, 7BJ, UK Tel: 451441, fa: 451414.
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fully commissioned within a further eight weeks. Benefits of DynaSand include substantial space savings and no automatic valves, sequencing or computer controls. Units operate un-manned, require no adjustment, and need only occasional visual checks and long-term servicing. Severn Water Services is the trading name of Nordic Water Products Ltd, part of the Swedish-based Nordic Water & Services, which is in turn a member of the multinational NCC group. Severn Water Services Ltd, Frederick Road, Hoo Farm Industrial Estate, Kidderminster, Worcs. DYll 7RA, UK Tel: + 44 (0)562 60400, fm: + 44 (0) 562 747419.
Sludgethickening by Flottweg centrifuge Bio Systems International Ltd, recently installed a Flottweg decanter centrifuge for an effluent plant installed by the company at RHM’s Golden Shred Works in Droylsden, Manchester. The process provides for aerobic treatment of the effluent. The treated effluent is then gravity settled, giving a waste activated sludge at 0.5 to 1.0% solids. Further thickening of this kind of sludge by gravity settlement is very difficult to achieve, but such large volumes of sludge had to be surplussed that thickening to reduce disposal costs was essential. Bio Systems selected a Flottweg decanter centrifuge for this thickening duty, after evaluation of the available technology, because it offers a variable impeller liquid discharge which facilitates pond variation during operating. When thickening sludges this allows easy start-up at shallow pond increase until optimum solids discharge is achieved. Similarly, when stopping, the impeller can be used to substantially
USpartnership for Bradford Metal In a far-reaching agreement with G A Kleissler Company of Lakeland, Florida, USA, the Bradford Metal Works group of companies has acquired exclusive licences to manufacture and market the Kleissler range of dust control equipment in the UK and Northern Europe. The two companies will also collaborate closely on a wide range of European projects, for which Bradford will provide Kleissler with a European manufacturing base, making Kleissler’s technology more costeffective as well as more readily available to industrial organisations within these countries. Kleissler’s commitment is to continue in its two speciality fields of air systems for sanitary paper making and converting, and pharmaceutical manufacturing. The company sees this commitment as a combination of equal parts of technology and customer service. The range of products which will be introduced into the Bradford Metal Works portfolio cover the Kleissler Vibratube dust separators, Unit dust separators, C series dust separators and Airjex dust separators. BMW will manufacture the Kleissler units at its production facilities in Bradford. They will then be marketed through BMW’s subsidiary Environmental Pollution Control Ltd a company already specialising in fume abatement and gas scrubbing. Bradford Metal Works, Eastwood Street, Bra@brd BD4 7DH, UK Tel: + 44 (0)274 725167, fa: f 44 (0)274 39034 6.
empty the machine during washing and shut-down. Flottweg, Krauss-Maffei House, Birchwood Boulevard, Birchwood, Warrtngton WA3 7PR, UK Tel: +44 (0) 925 822111, fax: + 44 (0) 925 828353. 353