Desalting we11 water A contract for a supplemental 6 mgd reverse osmosis water treatment system, to desalt feedwater containing 5,OOOppm TDS from deep wells in the Floridan Aquifer to a potable quality, suitable for blending with treated water from the existing lime softening plant serving Jupiter, Florida, has been awarded to Hydranautics. The system will use 8in diameter, spiral-wound, thin film composite polyamide membrane elements which are said to provide high salt rejection at low pressure. The company will be responsible for the design, manu-
Spending on odour control to increase The 1990 world market for hardware and services to and evaluate, measure, reduce odours will exceed $550m according to a recent report in Air Pollution Manageme,,t by The Mcllvaine Co. Both industry and municipalities are encountering substantial community resistance to odour emissions, and regulatory agencies are said to receive more nuisance complaints about odours than they do other air contaminants. The US sewage odour control market is identified as one of the fastest grcwing industry segmepts. Municipalities across the US are finding it necessary to invest in analysis and control equipment in order to continue operation. Plantsthat were originally installed without odour controlsystems are now being forced to add these systems. A large number of municipalities are turning to composting for sludge disposal. Many of the first composting systems have been installed without adequate odour control systems. This has resulted in citizens’ complaints. action by regulatory agencies and, eventually. the installation of odour control systems on a retrofit basis. This initial negative experience will result in odour control systems being furnished as an integral part of future compost facilities. Industry is also engaging in major investments to reduce odours. Twenty years ago major foundry expenditures for air pollution control were to reduce particulate emisFiltration
&Separation
facture and installation of the system, including pretreatment: RO process consisting of four trains with pressure tubes, membrane elements and piping headers; posttreatment, computer control and instrumentation. Completion is scheduled for May. A design feature will ire system flow control by permeate throttling instead of feedwater throttling. A control valve in the permeate line of each RO train will automatically adjust the permeate back pressure to all membrane elements. This feature will, it is said, avoid the loss of energy inherent with RO feedwater throttling. Hydranautics. PO Box 3690, Santa Barbara, CA 93130, USA.
sions from mould preparation and melting facilities. Now, investment in odour control systems in core making and other areas nearly equals the expenditures for particulate removal. 1990 estimates for hardware and system expenses including control devices as well as measuring devices worldwide are $350m. One of the major segments here is expenditures for scrubbers, adsorbers and retated devices. The world estimate in 1990 for this segment is $150m. which includes scrubbers as well as related fans, ductwork and controls. Included in this segment are biofilters, which are finding increasd use in Europe. In biofiltration micro-organisms in the soil eliminate odours as the air is filtered through the medium. Also included in this segment is a relatively new concept entitled biological scrubbing in which the odours are transferred to a liquid medium, and the liquid medium undergoes microbiological treatment in a separate reactor tank. Odour measurement devices called otfactometers are becoming increasingly sophisticated, and the latest devices can cost f40,OOO. These improved designs offer higher reliability and lower labour costs. The market for hardware and control systems is large in Europe and in the US. On a per capita basis, the Netherlands is ahead. The Netherlands holds the leadership position in a number of unenviable areas. It has the highest manure generation per m* of any country in the world. It also has a high population density. Other
January/February
1990
Easier cleaning A device that substantially reduces the need to open and clean its filters in the field has been developed by Amiad USA. Called a Torpedo, the unit is an insert adaptable to any 6 to 14in filter. When placed inside the filter, the Torpedo is said to create an increased water velocity along the internal screen surface and force all solids down toward the filter’s debris collection area. The high water flow rate generated is stated to be so
European countries have also encountered major odour problems and are spending substantial amounts to reduce them. European suppliers are taking the lead in the dedevelopment of biological scrubbing odour and measurement methods. The services sector in odour problem solving is nearly as large as the hardware sector. 1990 expenditures for conengineering, evalusulting, ation, community relations, testing, modelling. and related services are estimated at $200m worldwide. Odour evaluations are very labour intensive. As many as 10 panel members are required to sniff odour samples to determine intensity. No reliable analytical measuring devices are available since odours consist of just trace amounts of a wide variety of chemical compounds. Odour control often involves process changes. Since odour complaints make up a large percentage of citizen complaints, industry and municipalities alike find a substantial investment required in evaluation and consulting, control to avoid, or as a result of, nuisance related law suits. The Mcllvaine Co, 2970 Maria Avenue, Northbrook. Illinois 60062 USA.
great that debris cannot settle on the screen. There is said to be very little pressure loss, and no need to open the filter to remove the collected solids. They can be purged either through a blowthrouyh controller, by constant bleeding or through use of a hand valve. The unit, for which a patent is pending, is now incorporated into the company’s newest filter, the high efficiency Turboclean. available in 6-l 4in sizes. Amiad USA, Inc, PO Box A. Reseda. CA 9 1337, USA.
American expansion The North American Filter Co of Newark, New Jersey, has been acquired by Vokes on behalf of its parent company, BTR, for a cash consideration of $2.4m. The acquisition will provide an additional base for Vokes to develop and expand the manufacture and sale of its air and oil filters in North America. North American Filter, which has been a Vokes licensee since 1986, is currently engaged in the design, manufacture and marketing of filtration systems primarily for industrial air and gas applications. The factory will be expandeu from 20.000 to 70,000ft2 to accommodate the manufacture of other products in the wider Vokes range. A sales turnover of $lOm is planned for lS90. In addition, it is also planned to market the North American Filter specialised filtration systems in Europe. Vokes already owns the Refill’ Filter Co of Perth Amboy. New Jersey, manufdcturers of replacement air filter cartridges for industrial applications. Vokes Ltd. Henley Park, Guildford GU3 2AF.