A Waste Wizard filtration unit (foreground) recycles spent, light-duty aqueous cleaner at Pratt & Whitney's East Hartford, Conn., plant, thereby reducing alkali wastewater volume.

Each Waste Wizard, powered by a 110-volt electrical outlet, is connected to a sump or tank by hose. The unit uses a vacuum pump to draw spent cleaner across the surface of its planar membrane. Rotating discs with spiral grooves spin to create a vortex flow directly above the membrane surface to keep particulates from clogging the filter. Cleaned fluids are recycled into the process.

At P&W's North Haven, Conn., plant, two Waste Wizards filter wastewater collected in two settling tanks from a vibratory bowl that applies surface finish to ceramic-coated parts. Previously, the tanks were drained, cleaned, and refilled weekly, a task that took four hours. Since the Waste Wizards were installed, the task has been performed once a month within one hour.

The two filtration units cut the wastewater from the vibratory bowl process from 124,000 gallons a year to 12,000, and eliminated about $10,000 in annual treatment costs, according to Pratt & Whitney.

Etablissements Richard, a nickel plating company based in Argenteuil, France, developed a new process to produce nickel hypophosphite in an aqueous solution that can double nickel bath service life. The process, which uses conventional nickel and sodium hypophosphite solution, is currently being field-tested.

Nickel hypophosphite is a complex nickel salt that can be directly added to a nickel bath solution to provide the required oxidizing nickel ion and the reducing agent in the form of sodium hypophosphite.

When Etablissements Richard was unable to find a chemical supplier that could provide nickel hypophosphite solution in large quantities, the company decided to develop its own process to formulate the solution. It partnered with the Technomembranes University Laboratory in Montpellier, the Center of Research for Technology Transfer in Paris, and Novelect in Caen, France, to develop the new technology.

The process involves sending quantities of nickel sulphate dissolved in water through electrodialysis units, basically a series of electrically charged polymer membranes, to transform the nickel sulphate into the nickel hypophosphite solution that can be added directly to plating baths.

The Fyre-Block assembly consists of two seats: a primary polytetrafluoroethylene soft seat with a secondary 316 stainless steel seat and a disc strengthened by a heat-hardened nickel coating. The dual seat ensures tight bidirectional shutoff during normal operation. During a fire, even if the PTFE seat is completely destroyed, the stainless steel seat and disc remain in constant contact to maintain a seal.

Special dual seating keeps DeZurik's BHP valves (inset) sealed even in the event of fire.

The double-seat design also protects the valves from severe abrasion, as in a fly ash slurry application in a specialty chemicals plant. The plant's precipitators pump 700 to 800 gallons per minute of fly ash slurry at 275 psig a distance of 2.5 miles from the pump house to the facility's settling pond.

Plant management previously relied on lubricated plug valves for the job, but had to clean them frequently because fly ash buildup clogged them. They replaced them with eight BHP valves, installed in the pump house so that the slurry would flow into the seat side to protect the primary PTFE seat from abrasion. After a year without maintenance, plant workers examined the DeZurik valves during their annual cleanout and found no evidence of wear, damage, or slurry buildup.

Ullit's composite natural gas cylinders weigh about 60 percent less than steel cylinders.

The Ullit cylinders are made of a thermoplastic liner with carbon fibers and an epoxy matrix that exhibit nearly zero permeability over 28 days at 250 bar of pressure, a safety margin because the cylinders are aimed at an application that requires 200 bar pressures. The company claims its cylinders can be filled to 250 bar 100,000 times without being damaged.

In addition to their fatigue strength, the composite cylinders weigh one-third as much as steel cylinders with the same capacity. For example, a bus frame with a storage capacity of nine cylinders holding 33 gallons each at 200 bar, will have a total weight of 1,250 pounds when empty. This includes the cylinders, frame, fixings, piping, and accessories. By contrast, a similar bus frame equipped with steel cylinders would weigh 3,450 pounds empty.

The 3K-10 comprises a cylinder barrel, pistons, slipper retainer, and pressure plate made from a bimetal casting process that combines steel and Tocat 110 bronze.

Instead of bonding two metals by electrolysis or spraying, North American Hydraulics heats a steel pump piece to 1,800°F, pours a bimetal mixture (bronze and lead) into its cavities, then machines it to the desired tolerance. This manufacturing process produces a pump with the mechanical load-bearing properties of steel and the anti-friction and heat transfer characteristics of Tocat lead bronzes.

A bimetal casting process gives the APIS 3K-10 axis pump the load bearing properties of steel and the friction resistance of lead bronzes.

In addition, the APIS 3K-10 is equipped with four servo pistons, twice as many as in most similar pump designs, to more precisely position the swash plate and smooth overall pump operation at pressure ranges up to 6,000 psi continuous duty and 7,250 psi intermittent duty.

The pump was designed to be compact with a weight-to-horsepower ratio to suit equipment used in heavy construction, farming, forestry, and mining. For example, Old Dominion Brush in Richmond, Va., has incorporated the pump into the hydrostatic units that power the vacuum fans in its municipal leaf-vacuuming machines.

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