Reuse requirements

AWT Advanced Waste Treatment - any process of water renovation that upgrades treated wastewater to meet reuse requirements. 

Stockpiles of a sufficient volume of solid wastes should be supplied for reuse requirements. 

Reuse requires that components be built in a manner that is both generic—not overly tied to a specific application—and customizable so it can be adapted to specific needs. 

The courts have grappled with how to apply the mens rea and actus reus requirements to defendants who are asleep or unconscious. The criminal law reveals two main categories of cases related to sleep deprivation. The first involves a situation where the act of falling asleep or losing consciousness causes harm, as in the case of a sleepy driver. The other concerns a person who, while asleep or unconscious, performs an act that causes harm, as in the case of a person who, while asleep, kills his roommate. Before discussing these categories in detail, we review the two essential elements of criminal liability and how they relate to sleep deprivation. 

These studies show that, among many technical areas that require attention before a hydrogen-fueled aircraft can be a reality, one of the most important is thermal protection for the fuel tanks. Both the subsonic studies and studies of a hypersonic vehicle application indicate that low-density foams are attractive insulations for the LH2 fuel tanks, if reliability and adequate life can be established. Although this type of insulation has been used extensively for large throw-away booster stages for space application, the lack of reuse requirements has not demanded extensive investigation of the cyclic life of foam insulations. 

In fact, reuse requires a certain escalation in equipment of increasingly complex design and operation, which can be chosen since needs are more sophisticated (boilers, for example). In contrast, when seawater is conveniently available it can be used to cool heat exchangers if they have been specially designed. 

The Courtaulds semicommercial production system is iUustrated in Figure 8. Dissolving-grade woodpulp is mixed into a paste with NMMO and passes through a high temperature dissolving unit to yield a clear viscous solution. This is filtered and spun into dilute NMMO whereupon the ceUulose fibers precipitate. These are washed and dried, and finally baled as staple or tow products as required by the market. The spin bath and wash Uquors are passed to solvent recovery systems which concentrate the NMMO to the level required for reuse in dissolution. 

The older methods have been replaced by methods which require less, if any, excess sulfuric acid. For example, sulfonation of naphthalene can be carried out in tetrachloroethane solution with the stoichiometric amount of sulfur trioxide at no greater than 30°C, followed by separation of the precipitated l-naphthalenesulfonic acid the filtrate can be reused as the solvent for the next batch (14). The purification of 1-naphthalenesulfonic acid by extraction or washing the cake with 2,6-dimethyl-4-heptanone (diisobutyl ketone) or a C-1—4 alcohol has been described (15,16). The selective insoluble salt formation of 1-naphthalenesulfonic acid in the sulfonation mixture with 2,3-dimethyl aniline has been patented (17). 

A method for the polymerization of polysulfones in nondipolar aprotic solvents has been developed and reported (9,10). The method reUes on phase-transfer catalysis. Polysulfone is made in chlorobenzene as solvent with (2.2.2)cryptand as catalyst (9). Less reactive crown ethers require dichlorobenzene as solvent (10). High molecular weight polyphenylsulfone can also be made by this route in dichlorobenzene however, only low molecular weight PES is achievable by this method. Cross-linked polystyrene-bound (2.2.2)cryptand is found to be effective in these polymerizations which allow simple recovery and reuse of the catalyst. 

Similar to oil-fired plants, either low NO burners, SCR, or SNCR can be appHed for NO control at PC-fired plants. Likewise, fabric filter baghouses or electrostatic precipitators can be used to capture flyash (see Airpollution controlmethods). The collection and removal of significant levels of bottom ash, unbumed matter that drops to the bottom of the furnace, is a unique challenge associated with coal-fired faciUties. Once removed, significant levels of both bottom ash and flyash may require transport for landfilling. Some beneficial reuses of this ash have been identified, such as in the manufacture of Pordand cement. 

Relatively high (typically 980—1200°C) temperatures are required to decompose spent acids at reasonable burner retention times. Temperatures depend on the type of spent acid. A wide variety of spent acids can be processed in this way, but costs escalate rapidly when the sulfuric acid concentration in spent acid (impurity-free basis) falls below about 75%. A few relatively uncontaminated spent acids can be reused without decomposition by evaporating the excess water in concentrators, or by mixing in fresh sulfuric acid of high concentration. Weak spent acids are frequently concentrated by evaporation prior to decomposition. 

An important by-product of most energy technologies is heat. Few energy conversion processes are carried out without heat being rejected at some point in the process stream. Historically, it has been more convenient as weU as less cosdy to reject waste heat to the environment rather than to attempt significant recovery. The low temperatures of waste heat in relation to process requirements often make reuse impractical and disposal the only attractive alternative (see Process energy conservation). 

Water can seldom be reused directiy. The treatment required depends on the intended second use. Disposal costs of the wastewater must be included in any economic analysis, and additional treatment for reuse may be justified when this expense is included. Costs of reclamation depend on the location, water scarcity, availabiUty of pubHc water suppHes, and the intended reuse. 

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