Deep-cycle operation

Silver—Iron Cells. The silver—iron battery system combines the advantages of the high rate capabiUty of the silver electrode and the cycling characteristics of the iron electrode. Commercial development has been undertaken (70) to solve problems associated with deep cycling of high power batteries for ocean systems operations. 

The ocean surface water is warm (27° C at equator) and deep ocean water is cold (5°C at 2000 m depth). If a vapor cycle operates between these two thermal reservoirs, is water or refrigerant a better choice as the working fluid for this power plant ... 

Many types of automobile vehicles (see examples in Figure 10.5) use lead-acid batteries either for SLI purposes or engine powering. The first type of application uses SLI batteries, and the second type uses deep-cycle batteries. Both SLI batteries and deep-cycle batteries use exactly the same chemistry for their operation. The difference between them is mainly their design. 

SLI batteries are not designed for deep-cycling service, and very short lives are generally obtained with such operation. The deep-cycling capability of SLI batteries is covered in Sec. 23.5.2. 

Traction Battery A secondary battery designed for the propulsion of electric vehicles or electrically operated mobile equipment operating in a deep-cycle regime. 

Typical pilot-plant top-suspended baskets are 305 mm (12 in) diameter by 127 mm (5 in) deep. Commercial machines are available in sizes from 508-mm (20-in) diameter by 305-mm (l2-in) depth to 1524-mm (60-in) diameter by 1016-mm (40-in) depth and develop up to 1800g in the smaller and intermediate sizes. Except in the sugar apphcation, operation with a two-speed motor (half speed for loading and full speed for purging) is typical. Hydraulic drives with variable-speed capability are commonly used in the chemical industiy To maximize the number of cycles per hour, a combination of electrical and mechanical braking is employed to minimize the deceleration period, which is a transition period of no value to the process. 

Exchange of ionizable materials, primarily dissolved iron. Here the preferred media/process is resin bead deep-bed polishers. Resins may be operated in different cycle modes and where, for example ammonia, morpholine, or AVT programs are employed, specific operating conditions are necessary to avoid adverse effects of the ammonia anion cycle. 

Special formulations have been developed for cementing operations in arctic regions or for deep water applications [206,208,256,720,739,1792]. In low-temperature formations, wherein the cement is subjected to freeze-thaw cycling, freezing-point depressants must be added. Salts may serve as such, but traditional organic freezing-point depressants, such as ethylene glycol, also may be added [1022-1024]. 

When an aqueous slurry is filtered in a plate and frame press, fitted with two 50 mm thick frames each 150 mm square, operating with a pressure difference of 350 kN/m2, the frames are filled in 3600 s (1 h). How long will it take to produce the same volume of filtrate as is obtained from a single cycle when using a centrifuge with a perforated basket, 300 mm diameter and 200 mm deep The radius of the inner surface of the slurry is maintained constant at 75 mm and the speed of rotation is 65 Hz (3900 rpm). 

Incident solar energy is absorbed by the surface water of the oceans. Ocean surface temperatures in excess of 26°C occur near the equator. Pure water has a maximum density at a temperature of 4°C. The chilled water tends to settle to the depths of the ocean. The combination of the warmed ocean surface water and cold deep ocean water provides the thermodynamic condition needed to operate a heat engine called ocean thermal energy conversion (OTEC). A typical closed-cycle OTEC Rankine cycle using a working fluid such as ammonia or a freon is suggested. 

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