January 23, 2016
Regarding a previous History Mystery photograph of the Western Aluminum Producers (M.M. Al) Plant, Casey Roberts wrote: The metal framework that was in the foreground, and which has been identified as being in the local aluminum plant, is most likely an anode electrode used in melting the bauxite aluminum ore. If I remember correctly, there were at least a couple of lines of "pots" or electrolysis cells in the main building and each one would have had one of these anodes.
The anodes consisted of the steel framework seen in the picture which was filled with a mixture of carbon and coal-tar pitch, which was the actual anode. The "floor" of the inside of the steel frame appears to be the top of the pitch layer that would be several inches thick and in contact with the bauxite underneath it during the smelting process. The anode would have been hoisted up from the pictured location and moved to the pot lines to cover the pots after the cells were filled with bauxite.
The smelting of aluminum requires large amounts of current being passed through the bauxite in the electrolytic cell, which is the reason the plant was located here, near The Dalles Dam.
During a summer when I was in college, I worked as a lab technician at what was then the Harvey Aluminum plant and sampling the carbon/pitch mixture was something I did on occasion. I learned the hard way that the pitch is a "photo-sensitizing agent" when I got a severe sunburn after a short exposure to the sun.
Terray Harmon contributed to this report.
Last week’s History Mystery photo, above, was scanned from a 2 1/4 by 2 1/4-inch negative from the archives of The Dalles Chronicle.
The information on the envelop reads, “Western Alum. Producers (M.M. Al) Plant and staff pictures. March 15, 1979.”
Harmon noted the photo must have been taken in the foundry portion of the plant, where they manufactured “ingots, pigs and logs.”