Uhde cell

ELTECH System Corporation currently markets both the Hooker cells and Diamond cells. Other diaphragm-cell technologies developed during the 1970s include the Hooker-Uhde cell and the ICI-Solvay cell. These cell designs are addressed in Chapter 5. 

The Uhde cells [68,73] have a cathode surface area of 4-30 m. They have a machined steel cell bottom with rubber-lined sidewalls and end boxes. The inlet end box, through... 

Vertical diaphragm cells are either cylindrical or rectangular. The cylindrical cells include the Gibbs, Moore, and Wheeler cells [83,84]. The rectangular cell designs arc the Allen Moore, Townsend, Nelson, Hooker, Diamond, Solvay Cie, Kuieha Chemical, Nippon Soda, Showa Denka, and ICI cells. The only supplier of diaphragm cells today is ELTECH, who provides the Hooker H-iype and Diamond MDC-type electrolyzers. The reader is referred to Chapter 3 and the literature [66-68,71,85] for details related to the Hooker-Uhde cells and the earlier versions of the S- and H-type cells. 

The Uhde cells (Fig. 22, also see Fig. 25) are available with a cathode surface area 4-30 m for chlorine production rates 10-1000 t/d for the complete cell installation. The brine flows in via an inlet box fitted with two pipes for the removal of chlorine. The weak brine is removed at the end of the cell. The solid cover is fixed to the side walls by clamps. The anodes are suspended in groups in carrying frames supported near the cells on transverse girders with lifting gear. The anode rods are raised and lowered... 

Fig. 14. OxyTech/Uhde HU-type cell a, cell bottom b, cathode c, anode d, cell cover e, bus bars f, brine level gauge g, brine flow meter h, bypass...

In 1998, Krupp Uhde became the sole owner of Single Element Technology and continues to put great effort into the further development of membrane cell technology for different electrolysis applications. With a new patent [4] for improved Single Element Technology, Krupp Uhde is ready for the future. 

In 1997 Bayer AG increased chlorine production at its Uerdingen site by adding Krupp Uhde membrane electrolysers to the existing mercury cells. In order to achieve a high chlorine quality (minimum oxygen concentration) and maximum chlorine yield, the acidic process is run - namely the brine leaves the cells at a low pH of 2.5-3. 

Uhde, E., Borgschulte, A. and Salthammer, T. (1998) Characterization of the field and laboratory emission cell-FLEC flow field and air velocities. Atmospheric Environment, 32, 773-81. 

U-Gas, 160, 201 Uhde. See Ein Unternhmn von ThyssenKrupp Technologies Union Carbide Corporation, 281, 418 -19 UniPure Corporation, 296 United Catalyst/Sud-Chemie, 236 UOP LLC, 228-229, 281, 367, 419, 471 UTC Fuel Cell, 136-137, 255... 

Fig. 2 Uhde mercury cell, (a) Cell base (b) anode (c) cover seal (d) cell cover ...

Fig. 9 Uhde BM 2.7 electrolyzer, (a) Single element (b) contact strip (c) cell rack (d) busbar (e) inlet hoses (f) outlet hoses ...

The Hooker-Uhde Monopolar Membrane electrolyzer is shown in Figure 19. The active electrode surface of the HUMM electrolyzer is 1.7 m per cell element. The cell elements consist of anode frames of titanium and cathode frames of steel. Anode-cathode gap is approximately 3 mm. A separate frame is provided for holding the membrane. The electrode block rests on a support structure that serves as the header system for electrolyte and electrolysis products. Peformance of this electrolyzer is reported to be 2750 KWH/M ton NaOH at 35% caustic soda and 95% current efficiency at 3 KA/M current density (65). 

The main mercury cathode electrolytic cells used in the industry were developed chiefly by De Nora and Uhde, and to a lesser extent by IC1, Krebs Kureha, Olin and Solvay. 

Uhde E., Borgschulte A. and Salthammer T. (1997) Characterization of the Field and Laboratory Emission Cell (FLEC) Impact of Air Velocities on VOC Emission Rates. Proceedings of Healthy Buildings/ lAQ 97, Washington DC, Vol. 3, 503-508. 

And, at last, shortcomings of techniques, mentioned above, have caused a number of attempts to use hydrochloric acid as an electrolyte for hydrogen and chlorine obtaining. As far back as 1964, the firm "Hoechst" obtained 100 tons of chlorine per day with the help of a cell, worked out by the firm "Friedrich Uhde". This technique is widely used nowadays about 1 min tons of chlorine has been obtained by hydrochloric acid electrolysis by 1990. 

Other manufacturers such as Asahi Glass, Tokuyama Soda, De Nora, Oxytech, Chlorine Engineers and Uhde offer a variety of either monopolar or bipolar cells and most of these technologies now have representative plants. Membranes are almost all Nafion based. 

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