Cell house design

The current needed for cathodic protection by impressed current is supplied from rectifier units. In Germany, the public electricity supply grid is so extensive that the CP transformer-rectifier (T-R) can be connected to it in most cases. Solar cells, thermogenerators or, for low protection currents, batteries, are only used as a source of current in exceptional cases (e.g., in sparsely populated areas) where there is no public electricity supply. Figure 8-1 shows the construction of a cathodic impressed current protection station for a pipeline. Housing, design and circuitry of the rectifier are described in this chapter. Chapter 7 gives information on impressed current anodes. 

The concrete block walls of the cell housing the generator tube and associated components are 1.7 meters thick. The facility also includes a Kaman Nuclear dual-axis rotator assembly for simultaneous transfer and irradiation of reference and unknown sample, and a dual Na iodide (Nal) scintillation detector system designed for simultaneous counting of activated samples. Automatic transfer of samples between load station to the rotator assembly in front of the target, and back to the count station, is accomplished pneumatically by means of two 1.2cm (i.d.) polyethylene tubes which loop down at both ends of the system and pass underneath the concrete shielding thru a pipe duct. Total one-way traverse distance for the samples is approx 9 meters. In performing quantitative analysis for a particular element by neutron activation, the usual approach is to compare the count rates of an unknown sample with that of a reference standard of known compn irradiated under identical conditions... 

To facilitate a demonstration of the advantages of the 3-D architecture, we quantitatively compare metrics related to performance (e.g.. areal energy capacity, active surface area) of a conventional 2-D parallel-plate design with the 3-D interdigitated array cell (Figure 3). We assume a thin-film 2-D battery that comprises a 1-cm -area anode and cathode, each 22.5-/thick electrolyte. The total volume of electrodes and separator is 5 x 10 cm (the cell housing is ignored for simplicity, but is expected to be a comparable... 

Test equipment used included load cell hardness testers, in-house designed computer operated systems and commercial crush test apparatus. Representative samples were provided and a test portion of 50 to 200 pellets was obtained by riffling or splitting. The samples were then heated at 400°C for 3 hours and cooled in a desiccator, since moisture absorption by hygroscopic catalytic materials has been shown to affect crushing strength. (3)... 

In order to understand how anti-corrosive rubber linings are used in the caustic soda industry it is useful to have a broad understanding of the design, construction and operation of the process, mainly about the cell house where corrosion is severe. A brief description of design, construction and operation of mercury cells in the caustic soda industry is given next [11]. 

The transmission of power around the cell room once it is at the appropriate voltage and current also requires thought. The current is transmitted along bus-bars, normally constructed from copper or aluminium because of their exceptional conductivity, and the dimensions of the bus-bars are carefully calculated because of the considerable investment in the metal. Moreover, the connectors to the cells must be designed to avoid energy loss even at the very high currents and there must be switches which permit individual cells to be isolated for maintenance without disturbing the rest of the cell house. 

The present cell houses are designed for ease of operation and the absence of shorts and it is clear that they have a number of shortcomings, namely ... 

The flow cell was designed in-house. The main body was constructed out of Teflon with quartz windows and Teflon gaskets. The system was tested thoroughly with non-toxic materials to assure leak-free flow through. 

As can be seen elsewhere in this chapter, we have highlighted our success in our attempt to develop a full cell version of Li-air battery using an in-house designed proprietary test cell is as shown in Fig. 4.6. It is a great challenge to make such a cell, although many researchers use coin type cells with holes at the cathode cup. 

The Pt(H2) indicator electrode has been widely used for measiuing pHm in concentration cells housed in stirred Teflon-lined autoclaves (Palmer et al, 2001) and in a flowthrough design at temperatures below 300 °C (Sweeton et al, 1973). At temperatures above 300 °C the Pt(H2) indicator electrode was used in thermocells described in (Lvov et al., 1999, 2000b) and flow-through concentration cells (Sue et al., 2001). 

The almost universal replacement of carbon by metal anodes has led, by itself, to a reduction of the energy consumption by (0-15% (the cell voltage is changed by 0.45 V in —2.5 to — 5V). But, in addition, the chlor-alkali industry has benefited because anode replacement is no longer an important factor in the way the cell house is run and because the titanium to be coated may be fabricated in many forms This has helped to revolutionize cell design. 

The productivity of the cell house is poor the low current density and the cell design combine to give a low space-time yield Not only does this lead to large cell rooms but also to large quantities of metal being tied up in the cell house the residence time of a metal atom may be up to a month, and this represents a considerable investment at present prices. 

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