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The low-temperature heat discarded by a large power plant can produce large quantities of desalted seawater at low cost. This paper describes a system in which a horizontal tube multi-effect (HTME) desalination process is coupled to a large power plant (either nuclear or non-nuclear) in such a manner as not to interfere with the power cycle. The resulting product water is produced at a cost approximating present prices of water sold by water companies.

The size and cost of a multistage flash (MSF) distillation plant can be decreased by employing double-fluted tubes, oriented vertically, in the preheaters and condensers. Several plant configurations embodying this concept are discussed here. One of these concepts permits a closer temperature approach, resulting in a plant with reduced heat requirements. Similarly, the cost of multieffect processes such as the vertical tube evaporator (VTE) and the horizontal tube spray-film (HTE) can be reduced through the use of vertically oriented double-fluted tubes.

Dependable control systems are essential for the successful operation of a desalination plant. A well-operated process will prolong plant life, minimize maintenance costs, reduce energy consumption, and achieve the design output of desalted water. Poor process control, on the other hand, will result in scaling, corrosion, and reduced water output. In both thermal and membrane processes, temperatures, pressures, flow rates, and the concentration of additives must be carefully maintained at or near design values. Reliable pH control is essential to minimize corrosion and scale formation. This paper discusses the predominant desalination processes and, for each process, analyzes the influence of deviations in the operating parameters. Where possible, operating limits are indicated. The basic principles outlined herein are equally applicable to the newer variants of the basic desalination plant designs and to the combination processes now appearing on the market.

Recuperation de la chaleur perdue d'une grande centrale thermique pour la distillation de saumure ou d'eau de mer afin de produire de l'eau d'alimentation pour la chaudiere et de l'eau potable

Problems are considered that are encountered during the use of zirconium metal and zirconium hydride powders in the manufacture of vacuum tubes. The relative merits of binders and of various technics of coating tube elements with the finely divided metal or hydride are discussed. The problem of zirconium powder waste disposal is considered. Particular emphasis is placed on the handling of the two powders and the manufacturing hazards involved. Precautionary measures are outlined.