Dismantling

Care must be used when employing alkalis. In these circumstances joints tend to stick unless a lubricant is used. In addition it is advisable to rotate the units comprising the joint at frequent intervals. Apparatus in which alkalis have been used should be dismantled immediately after use. 

The simple spring clamps shown in Fig. XII, 2, 6 are recommended for the rapid assembly and dismantling of semimicro apparatus. These clamps have hardwood stems about 15 cm. long, which are slotted and... 

The Schwinger filter, shown in Fig. XI1,2, 17, finds application when dealing with very small quantities of crystals. The solid collects as a pellet above the small filter paper disc at the throat of the filter after dismantling, the pellet may be expelled by a snugly fitting glass rod. 

In plutonium-fueled breeder power reactors, more plutonium is produced than is consumed (see Nuclearreactors, reactor types). Thus the utilisa tion of plutonium as a nuclear energy or weapon source is especially attractive to countries that do not have uranium-enrichment faciUties. The cost of a chemical reprocessing plant for plutonium production is much less than that of a uranium-235 enrichment plant (see Uranium and uranium compounds). Since the end of the Cold War, the potential surplus of Pu metal recovered from the dismantling of nuclear weapons has presented a large risk from a security standpoint. 

Finally, candidate lubricants containing the antioxidants are tested in fleets of automobiles for thousands of miles. The engines are dismantled and examined for wear and coatings of varnish and other deposits. The lubricant is evaluated for sludge, viscosity, acidity, etc. Since evaluation in automobiles is expensive and time-consuming it is reserved for only the most promising candidates. Oxygen uptake tests are also used to measure oxidative stabiUty (28). 

The demand for arsenic metal is limited. The 1990 U.S. requirement for metallic arsenic was supphed by the People s Repubhc of China. Arsenic was formerly supphed domestically (1974—1986) by ASARCO Inc., which dismantled its operation because of economic and environmental pressures, and by imports from Bohden Metah, Sweden, which suspended production in late 1987 because of the low price offered by China. 

The nondepreciable investments, ie, land and working capital, are often assumed to be constant preoperational costs that are fully recoverable at cost when the project terminates. Equipment salvage is another end-of-life item that can represent a significant fraction of the original fixed capital investment. However, salvage occurs at the end of life, can be difficult to forecast, and is partially offset by dismantling costs. Eor these reasons, a zero salvage assumption is a reasonable approximation ia preliminary analysis. 

Bolted joints are friendlier than quick-release couplings. The former are usually dismantled by a fitter after issue of a permit to work. One person prepares the equipment and another person opens it up the issue of the permit provides an opportunity to check that the correct precautions have been taken. In addition, if the joints are unbolted correctly, any trapped pressure is immediately apparent and the joint can be remade or the pressure allowed to blow off. In contrast, many accidents have occurred because operators opened up equipment which was under pressure, without independent consideration of the hazards, using quick-release couphngs. There are, however, designs of quick-release couphngs which give the operator a second chance. 

Shell rupture protection is a vital consideration in externally protected capacitor units. Since there is no control over small internal faults until they become major fault, protection can be provided only for the whole unit and the entire unit has to be dismantled after such a fault. In fact, the capacitor bank may have lo be shut down completely to replace the lost unit with a new one lo avoid an imbalance, besides making up for the lost capacitance. 

Artefacts Screwdrivers dismantled spark plug PVC yachting anorak, polymer rope, etc. 

For large vessels, a manway and internally dismantled cone may be used where more economical. 

Pistons may be of segmented construction to permit the use of one-piece wear bands. One-piece wear bands are a requirement in API 618. Pistons have a problem in common with humans—a weight problem. Weight in a piston contributes directly to the compressor shaking forces and must be controlled. For this reason, aluminum pistons are often found in larger low pressure cylinders. Hollow pistons are used but can pose a hazard to maintenance personnel if not properly vented. If trapped, the gas will be released in an unpredictable and dangerous manner when the piston is dismantled. 

Irregular Plant maloperation (e.g. unauthorized venting ) Plant failure - spillages, pipe joint failures Start-up/shutdown Dismantling/demolition Unauthorized waste incineration (rubbish burning) Fires ... 

High headroom is required for dismantling the entire plate stack. 

HjS flare headers should be constructed for each of isolation, washing out and dismantling for cleaning. The need for periodic cleaning of the HjS flare header must be recognized, and alternative routing for HjS releases must be provided for such occasions if a shutdown of the HjS sources cannot be tolerated. 

Preferably, the HjS flare system should consist of a segregated header and separate line routed up the side of a conventional elevated flare stack, sharing the same structure, pilots and igniters. However, the HjS header may be tied into the regular flare seal drum if there are special mechanical design problems associated with the separate stack e.g., in the case of a flare which is to be dismantled for overhaul. Flare elevation must be sufficient to meet atmospheric pollution and ground level concentration requirements for the sulfur dioxide produced. 

The design and implementation of inherently safer chemical processes includes consideration not only of the people operating and maintaining the plant while it is in operation, but also the safety of those who may later use the plant for other purposes. This includes dismantling... 

A designer fails to identify and consider the environmental land use implications of dismantling a process at the end of its useful life. 

Deactivation and certain decontamination and dismantlement (D D) activities that do not fall under CERCLA... 

For large superfund sites, the proeess ean be similar to the DOE proeess as deseribed. Onee the site has been adequately assessed, a remedy ean be ehosen. This remedy ean vary but eould inelude a removal or stabilization phase, a treatment phase, a maintenanee phase, and, finally, dismantlement and deeontamination phases. 

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