Anode adjustment system

The Olin cells [68] have machined steel cell bottom units with rubber-lined steel side channels and steel tops. The anode stems are sealed through individual flexible rubber sleeves and are suspended from a copper channel, which also carries the current from the flexible buses to the anodes. Olin has developed a novel system to mount and adjust the anode-cathode gaps. The U-shaped copper or aluminum bus bar, located above each row of anodes, provides support to the anode lifting gear and current to the anodes, which are bolted to it. The anodes can be adjusted manually or electronically with the remote computerized anode adjusted (RCAA) system. 

The special feature of the Olin-Mathieson cell lies in the system of mounting and adjusting the anodes. Above each row of anode rods, a U-shaped copper or aluminum bus bar also serves to support the anode lifting gear. The anode rods are bolted to the U-shaped bus bar. The anodes are adjusted as a group, either manually or by a remote computer with the remote computerized anode adjuster (RCAA) system. The currents are measured independently of the cell potentials by means of reed contacts [90]. 

Current is fed into the electrolyzer by means of anodic and cathodic end elements. The anodic compartment of each cell is joined to an independent brine feed tank by means of flanged connections. Chlorine gas leaves each cell from the top, passing through the brine feed tank and then to the cell room collection system. Hydrogen leaves from the top of the cathodic compartment of each cell the cell Hquor leaves the cathodic compartment from the bottom through an adjustable level connection. 

The reaction mixture is filtered. The soHds containing K MnO are leached, filtered, and the filtrate composition adjusted for electrolysis. The soHds are gangue. The Cams Chemical Co. electrolyzes a solution containing 120—150 g/L KOH and 50—60 g/L K MnO. The cells are bipolar (68). The anode side is monel and the cathode mild steel. The cathode consists of small protmsions from the bipolar unit. The base of the cathode is coated with a corrosion-resistant plastic such that the ratio of active cathode area to anode area is about 1 to 140. Cells operate at 1.2—1.4 kA. Anode and cathode current densities are about 85—100 A/m and 13—15 kA/m, respectively. The small cathode areas and large anode areas are used to minimize the reduction of permanganate at the cathode (69). Potassium permanganate is continuously crystallized from cell Hquors. The caustic mother Hquors are evaporated and returned to the cell feed preparation system. 

The adjustment of a protection station or of a complete protection system where there is stray current interference is made much easier by potential control. Potential control can be indispensable for electrochemical protection if the protection potential range is very small (see Sections 2.4 and 21.4). This saves anode material and reduces running costs. 

A tank with a fixed cover of plain carbon steel for storing 60°C warm, softened boiler feed water that had a tar-pitch epoxy resin coating showed pits up to 2.5 mm deep after 10 years of service without cathodic protection. Two separate protection systems were built into the tank because the water level varied as a result of service conditions. A ring anode attached to plastic supports was installed near the bottom of the tank and was connected to a potential-controlled protection rectifier. The side walls were protected by three vertical anodes with fixed adjustable protection current equipment. 

Manually Controlled System A manually controlled system comprises one or more transformer-rectifiers each with its associated control panels which supply the d.c. to the various anodes installed in the water box spaces. Each transformer-rectifier is provided with its own control panel where each anode is provided with a fuse, shunt and variable resistor. These enable the current to each anode to be adjusted as required. Reference cells should be provided in order to monitor the cathodic protection system. In the case of a major power station, one transformer-rectifier and associated control panel should be provided for separate protection of screens, circulating water pumps and for each main condenser and associated equipment. 

In electrochemical systems, many restrictions exist in the use of metal catalysts. Most metals other than the expensive noble metals are unstable at anodic potentials and cannot be nsed for anodic processes. The catalytic activity and selectivity of metal catalysts basically are determined by their chemical nature and are rarely open to adjustments. 

MNH4C1 plus NH3, pH 8.0 Same system adjusted to pH 9.5 Anodic wave at pH 0 due to HgSe Anodic wave at pH 12 (0.01M NaOH)... 

In an electrochemical enzyme membrane reactor an electrochemical flow-through cell using a carbon-felt anode is combined with an enzyme-membrane reactor. The residence time is adjusted by the flow of the added substrate solution. The off-flow of the enzyme membrane reactor only contains the products p-hydroxy benzaldehyde and p-hydroxy benzylalcohol. By proper adjustment of the residence time and the potential, total turnover of the p-hydroxy toluene, which is introduced into the reactor in 13 mM concentration, can be obtained. In a 10-day run, the enzyme underwent 400000 cycles and the polymer-bound mediator, which was present in a higher concentration than the enzyme, underwent more than 500 cycles. At the end, the system was still active. By proper selection of the residence time, one can either... 

B. Reduction of o-chloronitrobenzene. The stirrer is set in position carefully inside the cathode, which is clamped in place at the top. The porous cup, previously impregnated with the electrolyte, is charged with 11.5 g. (0.073 mole) of o-chloronitrobenzene (Note 5) and about 80 ml. of a mixture of acetic acid (70 ml.), concentrated sulfuric acid (22 ml.), and water (8 ml.) (Note 6). The cup is then clamped securely in position, and the beaker containing the anode is supported just clear of the bottom of the porous cup and filled with the same solution of aqueous sulfuric and acetic acids to the same level as the liquid inside the cup. The stirrer is started, the current turned on, and the system observed for a few minutes until the current has become stable. It is then adjusted at some convenient value no greater than 2 amperes. 

The sensor consisted of a vacuum tube containing a filament, grid and anode, very similar in form to the thermionic triode valve. An adjustable leak was arranged to feed a portion of the column eluent into the gauge which was operated under reduced pressure. The sensor was fitted with its own pumping system and vacuum gauge and the usual necessary cold traps. Helium was used as a carrier gas and the grid collector-electrode was set at +18 V with respect to the cathode... 

Gently fill the upper reservoir and connect the electrodes to the electrophoretic apparatus. Be sure that the anode is at the bottom. 6-33. Energize the power supply and adjust it to an output of 3 to 4 mA per gel tube (i.e., 21-28 mA total for a total of 7 tubes). DO NOT TOUCH THE SYSTEM BECAUSE A FATAL ELECTRICAL SHOCK MAY RESULT. Allow the system to operate in this manner for 15 to 20... 

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