Cellhouse replacement

There are two distinct situations in which a company may be building a new cellhouse. The first is the common situation of a brownfield project at an existing plant. This is either a complete replacement of an old cellhouse, or an expansion of an existing facility. 

The motivations for replacement of an old cellhouse are nearly always the same reduce manpower for manual cathode stripping, improve workplace conditions for the employees, and reduce power costs. The need to expand capacity or improve product purity can be factors as well. It is also frequently the case that an old manually stripped cellhouse has high maintenance costs and may need major repairs to stay in operation. 

The replacement cellhouse has the fallback position of using the old facility in the event of a construction delay. This will provide the necessary zinc production, but it does come at a... 

Eventually, as the anodic process continues, a hard, dense, protective layer of Pb02 is formed on the anode surface. Once this protective film has been formed, cathode contamination decreases and the amount of sludge generated by the anode decreases as well. This process (called conditioning) may take 30-60 days or more depending on the anode composition and current density (1). Because of the difficulty in conditioning anodes, operators of zinc cellhouses are very reluctant to replace an entire cell of used, conditioned anodes with new, unconditioned anodes. Operators will normally replace only one or two anodes per cell or try to condition the anodes prior to use in the cells. 

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