Hauling

Figure Bl.26.3. The lUPAC classification of adsorption isothemis for gas-solid equilibria (Sing K S W, Everett D H, Haul RAW, Mosoul L, Pierotti R A, Rouguerol J and Siemieiiiewska T 1985 Pure. Appl. Chem. 57 603-19).

As described above for small a and NA, a fibre is single mode if U < 2.405. Here only one mode, with one group velocity, is possible. This lack of modal dispersion is why single-mode fibre dominates transport media in long-haul communication systems. 

Aquaculturists may harvest, and even process their own crops, although custom harvesting and hauling companies are often available in areas where the aquaculture industry is sufficiently developed to support them. Some processing plants also provide harvesting and hve-hauling services. 

Weighing the loaded car on a coupled-in-motion track scale. An entire train, typically, is hauled at slow speed over the scale. The net weight is determined by subtracting the tare weight stenciled on the car... 

In the early 1990s, there were more than 9 x 10 km of fiber-optical telecommunication links in practical use in the United States. In addition, many other countries, notably Canada, Japan, and western Europe, have installed extensive fiber-optic communication systems. There are several transoceanic fiber-based telephone cables. Fibers are in use for intracity telephone links, where bulky copper [7440-50-8] wine is replaced by thin optical fibers. This allows crowded conduits in large cities to carry more messages than if copper wine were used. Fiber optics are used for intercity long-haul telephone links, for interoffice tmnk lines, and have replaced many microwave communication links. 

Shipping. Bulk milk is hauled to the processing plant in insulated tanks using tmck tanks or trader tankers. The milk is transferred from the bulk tank to the tanker with a positive or centrifugal-type pump. For routes of some distance, pick-up every other day reduces handling costs. 

Prior to deposition on a moving belt or screen, the molten polymer threads from a spinnerette must be attenuated to orient the molecular chains of the fibers in order to increase fiber strength and decrease extendibiUty. This is accompHshed by hauling the plastic fibers off immediately after they have exited the spinnerette. In practice this is done by accelerating the fibers either mechanically (18) or pneumatically (17,19,20). In most processes, the fibers are pneumatically accelerated in multiple filament bundles however, other arrangements have been described wherein a linearly aligned row(s) of individual filaments is pneumatically accelerated (21,22). 

The western phosphates are sedimentary deposits in adjoining areas of Wyoming, Idaho, and Utah derived from a former inland sea. They consist of layers of limestone, phosphate, and chert, now budded and faulted so they are rarely horizontal. The phosphate ore is strip-mined using large earth-moving equipment such as shovels, scrappers, dump tmcks, and bulldozers to mine the overburden and phosphate ore. Mining ratios of overburden to metric ton of recovered ore are from 1—3 m /1 (2—4 yd /short ton). The typical mining practice is to remove ore and overburden from a pit in discrete layers (Lifts) of 10—20 m in depth. Overburden from the pit is back-hauled to a previously mined pit. Extensive land reclamation practices are later carried out to return the mine areas to natural states. 

In stands where partial cuttings are made, cut-to-length systems are used in which a delimber and cut-off saw are incorporated into the sawhead. The products are bucked, separated into piles, and then hauled to the roadside on a forwarder, which carries the whole load. The limbs and tops are left... 

At Great Salt Lake Minerals Corporation (Utah), solar-evaporated brines are winter-chilled to —3° C in solar ponds. At this low temperature, a relatively pure Glauber s salt precipitates. Ponds are drained and the salt is loaded into tmcks and hauled to a processing plant. At the plant, Glauber s salt is dissolved in hot water. The resulting Hquor is filtered to remove insolubles. The filtrate is then combined with soHd-phase sodium chloride, which precipitates anhydrous sodium sulfate of 99.5—99.7% purity. Great Salt Lake Minerals Corporation discontinued sodium sulfate production in 1993 when it transferred production and sales to North American Chemical Corporation (Trona, California). 

Although Hquid carboa dioxide may be stored without loss ia tanks and cylinders, dry ice undergoes continuous loss ia storage because of sublimatioa. This loss can be minimised by keeping the dry ice ia iasulated boxes or bias. Special iasulated rail cars and tmcks are used for hauling dry-ice blocks. Most plants produce the material at the time it is sold to avoid storage losses and rehandling costs. 

Sylvinite is removed from the ponds with scraper-loaders and hauled to a central pit. The salts are then transported to the refinery in a slurry line. KCl is separated from the NaCl by flotation. The flotation process is standard throughout the industry and is the same process used to separate KCl from impurities in a camaUite decomposition process explained later. An amine collector is used as one of the reagents. 

Whereas an explosion from methane tends to be localized, it may start coal dust explosions resulting in more widespread injury and loss of life. AH coal breaking operations result in formation of fine coal particles some are controlled with water during the mining operation. Breakage associated with hauling disperses dust, and dust accumulations can be made safe by rockdusting. Powdered limestone is spread over the mine surfaces to cover the dust. 

The economics of some mines frequentiy depend heavily on the revenues derived from leaching the waste to recover additional copper. This waste material, which has to be removed to uncover the ore, may be hauled to specially constmeted dumps, where the sulfides, the most common form of copper mineral, are oxidized and the leach solution can contact the waste material uniformly. Economics sometimes precludes optimization of dumps for leaching operations because of such factors as compaction, size distribution, and terrain (16). 

Cut, erect, align, fit, bolt, thread or weld, and test Handle and haul, store, scaffold, lost time, tools and rentals, contractor s overhead and profit Craft rate, productivity, height, and complexity... 

Container sliips have guides in the hold and on deck which hold boxlike containers or tanks. The tank is latched to a trailer chassis and hauled to shipside. A movable gantiy, sometimes permanently installed on the ship, hoists the tank from the trailer and Towers it into the guides on the ship. This system achieves large savings in labor, but its apphcation is sometimes limited by lack of agreement between ship operators and unions. 

Crushed Stone and Aggregate In-pit crushing is increasingly being used to reduce the rock to a size that can be handled by a conveyor system. In quarries with a long, steep haul, conveyors may be more economic than trucks. The primaiy crusher is located near the quariy face, where it can be suppRed by shovels, front-end loaders or trucks. The crusher may be fully mobile or semimobile. It can be of any type listed below. The choices depend on individual quariy economics, and are described by Faiilkner [Quairy Management and Products, 7 6), 159-168 (1980)]. 

The use of closed railroad cars has declined somewhat in the handling of packaged chemical products in favor of trailers hauled pig-... 

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