Chlor-Alkali Plant's Mercury Emissions Still a Mystery

The mercury emissions stemming from chlor-alkali plants have long been viewed as some of the most concentrated, and perhaps easiest to stop, to those looking to remove unnecessary mercury emissions from our environment. The "old" chlor-alkali process for manufacturing chlorine uses tons and tons of mercury, a lot of which goes unaccounted for, and it should simply be stopped.

It should be noted that 53 of the 59 chlorine plants in the US have already voluntarily abandoned the "old" processing method that uses mercury and have gone to a mercury free method, and for that the industry should be applauded. One of the remaining plants, the one in Port Edwards, WI recently expressed a desire to switch over and was asking the Public Service Commission in WI for a special electricity rate to help them out. Hg-ATME supported this move in a recent post on this subject.

In a ruling, that may have been sound considering all the related parties, this request for special rates was denied. It would have been nice if just this once PSC could have granted a special case, it would have meant so much, but they didn't want to set a precedent, and probably rightly so. This Pioneer Press article explains the PSC's thinking. I hope that ERCO will continue to look for ways to convert their process.

A recent article in the Atlanta Journal-Constitution details some of the real issues with this manufacturing process. Literally tons and tons of mercury go unaccounted for annually in this seemingly unregulated industry. While some 450 coal burning power plants, consisting of some 1300 generating units, emit an estimated 48 tons of mercury annually in the US, this handful of chlorine plants reported emissions of 6.7 tons themselves in 2005. The AJ-C article also shows how this is probably way underestimated at that.