The trucks haul high-energy wastes, including leftover paints, inks, dyes, cleaning fluids, and spent motor oil and solvents, to the cement plant, where they are pumped into cement kilns and incinerated at 2,800°F. This high temperature destroys the organic compounds in the hazardous wastes and turns limestone, shale, ash, and sand into cement clinker.

An operator uses the Bristol M7 cleaner to remove hardened waste residues from a truck at Lone Star Industries' Greencastle, Ind., cement plant.

About 60 trucks per month come into the Greencastle plant with residues of sludge or hardened solids, called "heels," which can account for up to half the truckload. According to Indiana law, trucks delivering these wastes must be 99.7 percent empty before they depart a cement kiln.

Lone Star Industries needed a system powerful enough to wash out the heel formations and selected the Model M7 truck cleaner manufactured by Bristol Equipment Co. Bristol's rugged truck cleaning systems have been used to clean out challenging semi-solids, such as asphalt sludge, calcium carbonate, kaolin clay, tar products, and silica pigments.

The M7 consists of a nozzle that directs a jet of up to 250 gallons per minute of solvent at pressures up to 250 pounds per square inch, into the truck tank through the access port. A small, electrically driven compressor provides the unit with air that sends the solvent into the tank. An operator uses mechanical cams, powered by two hydraulic circuits, to control the movement and speed of the nozzle to play the jet over the heel formation. Lone Star Industries can now remove half a truckful of a solid heel formation within 20 to 30 minutes, which is significantly faster than other cleaning systems the company has tried, according to Jamie Robinson, process supervisor at the Greencastle cement plant.

The Montsouris reservoir cracked when it was first filled with water, a scant three years after the end of the Franco-Prussian War, due to load fluctuations caused by daily use and the strain of thermal shocks that opened up the concrete layer of the reservoir. "We have recorded temperatures varying from 32° to more than 68°F in the space of a single day," said Francis Maquennehan, an engineer at Sagep who helped restore the reservoir.

Sagep repair crews apply the System K compound of hydraulic binders and resins in dispersion to the century-old concrete walls of the Montsouris reservoir in Paris to prevent leaks.

Over the years, French repair crews patched up cracks with liquid coal-tar pitch or cement grout, but these materials did not survive long. Sagep's diagnosis on one of the upper basins of Montsouris in the early 1990s revealed a 13,210-foot-long line of cracks and daily water losses estimated at 16,000 gallons.

Maquennehan and his colleagues conducted a series of experiments to find a lasting repair technique for the historic reservoir. Early attempts to apply polyurethane on the concrete waterproofing at other Parisian reservoirs serving the Menilmontant and Montmartre districts failed, as did the application of epoxy resins. The Sagep designers decided to create a new repair material that combines the ability of elastic impermeable products to form a watertight seal with the ability of hydraulic binders to survive cold and dampness when applied to porous concrete.

Sagep worked with Kristo of Ville-La-Grand, France, to develop System K. This involves scouring the existing layer of concrete waterproofing to uncover a solid structural surface, and then applying a primer of crystallizing elements. Taking advantage of a property of concrete, these elements mineralize the capillaries and microfissures in the concrete to provide cohesion in depth. Then, three layers of waterproofing are sprayed on. Each layer consists of an impermeable compound based on hydraulic binders and resins in dispersion, with the second layer being reinforced with a nonwoven geotextile, an earth-holding fabric.

Sagep is restoring 315,000 square feet of concrete waterproofing in the second upper basin of Montsouris, and expects to finish leakproofing by the end of the year. Based on its success at the 19th-century Parisian reservoir, Kristo is exporting System K to Vietnam, where it will be used to restore a 14.1-million-cubic-foot reservoir in the suburbs of Ho Chi Minh City.

The MicroMark spray system is used for the purpose of color coding automotive components.

The MicroMark comprises a precision spray valve that is supplied with ink or paint from a pressurized tank equipped with a constant-bleed regulator to prevent fluctuations in fluid pressure. Operators use a microprocessor-based controller mounted near the spray valve, typically interfaced with a programmable logic controller, to set up and regulate the spray pattern. The valve relies on low-volume, low-pressure air to apply ink or paint without any mist or overspray.

Electronics assemblers make use of the MicroMark specifically to mark parts that pass particular tests or require reworking. Auto parts suppliers mark and differentiate brake shoes that are slightly larger or smaller than their counterparts. Paper goods companies use the precision spray valve system to mark a predetermined napkin in a stack to aid in packing, while metal tubing makers use it to identify products that have passed welding tests.

Vintners load grapes between the two layers of a double-layered, cylindrical pressing tank. The inner layer of the tank is a bladder made of a material similar to vinyl that is pneumatically expanded to crush the grapes against the wall. The outer layer of the tank is made of stainless steel filled with glycol in order to control the temperature of the juice. Engineers provided the tank with a stainless steel door equipped with a pneumatic seal on its outside lip to keep the inner envelope airtight.

The airtight, temperature-controlled envelope within this pneumatic grape press optimizes extraction, steeping, and thus quality of juice it produces.

By maintaining the optimum temperature for the juice to steep, the press enhances juice quality. The seal protects the juice from oxidation through air contact, a problem that can occur with traditional juice tanks. A flow sensor optimizes the pressing extraction time.

In addition, Le Materiel Pera developed a pressing program that is used in concert with its pneumatic press. This involves measuring the conductivity of juice samples, which is directly related to important quality parameters including pH, potassium content, and the total polyphenol index. Vintners using the program are able to better control the flow of free juice and pneumatic draining, making it possible to extract up to 75 percent of the grape juice, about 5 percent more than most presses.

The pneumatic press won a gold medal at the most recent international exhibition of wine production equipment held in Montpellier, France, in November. The press is used extensively in the Bordeaux region of France, in other European wine countries, and in South America and South Africa. In California's Napa Valley, both the Cosentino Winery in Yountville, and Rombauer Vineyards in St. Helena use the press.

The Phillips alkylation process used at the Lytton plant uses hydrofluoric acid as a catalyst to combine light hydrocarbons that are too volatile for use in gasoline in a reactor to form alkylate, a high-octane blending agent to produce unleaded gasoline. Using a nonmechanical reactor to blend the acid and hydrocarbons eliminates pumps and stirrers, and their associated maintenance, and also avoids the need for high operating pressures that would be required to move the acid catalyst through other alkylation systems. About 3,600 barrels of alkylates are produced daily at Lytton.

In case of a leak, Caltex Oil Refineries operators can empty this hydrofluoric acid alkylation reactor at the Lytton refinery into a secure storage tank swiftly to minimize the hazard.

Caltex engineers worked with Phillips representatives to use the latter company's inventory management process to beef up the safety of the alkylation process at the Brisbane plant. For example, Caltex engineers installed a new reactor/settler and elevated acid coolers, basically heat exchangers, which use gravity to empty themselves rapidly into a secure storage vessel below if refinery power or pumps fail.

Remotely operated water cannons and cameras were placed at several points where a potential acid leak might occur, and are operated from the refinery's master control room. The cannon can supply sufficient water to knock down any leak and contain the acid within the confines of the process area. Several liquid propane gas detectors line the perimeter of the alkylation unit to signal the control room in case of leaks.

As an added precaution, a water curtain, created by a series of pipes fitted with spray nozzles, surrounds the fresh acid storage drum. If an acid catalyst leak is detected, automated valves flood the pipes with water, creating an aqueous curtain that scrubs acid from the atmosphere and traps acid that falls to the ground so that it can be collected, treated, and sent to the refinery's wastewater system.

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