Wet storage

In dry air the stability of zinc is remarkable. Once the protective layer of zinc oxide formed initially is complete, the attack ceases. Even under under normal urban conditions, such as those in London, zinc sheet 0 -8 mm thick has been found to have an effective life of 40 years or more when used as a roof covering and no repair has been needed except for mechanical damage. The presence of water does, of course, increase the rate of corrosion when water is present the initial corrosion product is zinc hydroxide, which is then converted by the action of carbon dioxide to a basic zinc carbonate, probably of composition similar to ZnCOj 3Zn(OH)2 . In very damp conditions unprotected zinc sometimes forms a loose and more conspicuous form of corrosion product known as wet storage stain or white rust (see p. 4.171). 

White rust If a fresh zinc surface is allowed to stand with large drops of dew on it, as may easily happen if it is stored in a closed place in which the temperature varies periodically, it is attacked by the oxygen dissolved in the water, owing to differential aeration between the edges and the centres of the drops. A porous form of zinc oxide builds up away from the surface and quickly takes up carbon dioxide from the air to form the basic carbonate known as white rust or wet storage stain. 

Wet storage of LP boilers, FT boilers, and WT boilers, either without superheaters or with fully drainable superheaters, is achieved by being filled to overflowing with hot, treated water and a very small but continuous overflow maintained during the idle period. 

As shown in this table, a zero discharge of process waste-water pollutants is required by EPA for all facets of the timber products industry except wet storage of legs, wet-process fiber products manufacture, and one segment of the wood preserving industry. This requirement, by definition, holds that a zero discharge is "the best practicable technology currently available" by which the affected industries can control pollution. 

In 1980 the construction started for an underground interim storage for all SNF from the Swedish NPPs. It was taken into operation in 1985. It is a wet storage and is located close to the Oskarshamn NPP. 

Wet" storage in standard-quality medium/off normal-quality medium and... 

C. acidophilia was Immobilized In asymmetric UF membranes by several methods without loss of enzyme activity. The results Indicated that no marked decrease of activity was observed after 8 to 9 months of wet storage at 4 C. The membrane had a flat sheet configuration and were tested In standard ultrafiltration systems. 

A schematic flow diagram indicating the essential equipment in the allyl chloride process is shown in Fig. 6-11. Propylene from wet storage flows... 

The Small Boat Wet Storage Basin in Charleston, South Carolina, has been the launching point for a horrendous dumping at sea of chemical weapons. Approximately 24 barges of Lewisite were dumped at sea between August and October 1946, and one in 1948. 

Nuclear wastes are generated from spent nuclear fuel from electric power plants, dismantled weapons, and products such as radio pharmaceuticals. The most important design item for the safe storage of nuclear waste is the effective shielding of radiation. To reduce the probability of nuclear radiation exposure, special packaging is designed to meet the protection standards for temporary dry or wet storage or for... 

It is important that the grain of the label paper is correct and that the appropriate adhesive is applied. The label has to adhere readily and effectively, remain in place during its journey to the customer and in dry or wet storage. Finally the label must detach easily in the bottle washer. Adhesives include (/) dextrins, ( ) jelly gums and iii) casein which will retain the label even if the bottle is immersed in ice-cold water. 

While wet storage has operational advantages, it imposes extra loads on the con-finitig vessel. The mass is heavier because of the interstitial brine, and the fluidity of the contents adds a horizontal thrust on the walls. Also, when the vessel is used to accumulate... 

Plant design must also cater to the shutdown of one line of cells. If the diaphragm cells are shut down, the mercury cells can operate on stockpiled evaporator salt or purchased salt. If neither is available, the mercury cells will be forced to shut down. In the case of a mercury-cell shutdown while evaporator salt is still being produced, the salt can be stockpiled in a resatmator (see Section 1.22.2 for a discussion on wet storage of salt) or used to produce new brine. The latter approach probably involves curtailment of production from the diaphragm cells. 

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