That process should be of interest to people with acid generating ores which uptake metal. No situation I am familiar with has this problem in spades however. I tend to stay away from those kind of ores.
I had heard of the company. What you will find is that most companies tend to stay away from patents as they have to pay for them, which kind of prevents them from calculating an in-house fixed cost to the problem.
Most companies could have paid for a catalytic solution to SO2 smelter off-gas and acheived a 99.7 % reduction by paying a dollar a ton for effluent. Instead they chose to say to legislators that such a solution did not exist (patented in 1958 by some U of T professors) and lobbied to pay for pollution levels in the 40% range. Inco even spent 100 million dollars on their own 90% reduction solution, far from superior to the one existing, and only acheived that after 35 years.
In that time, Inco would have spent $214,620,000 on patent fees (700 tons per hour SO2 for 35 years) and $75,000,000 on plant costs. But, they would have recouped 214,620,000 X 75 = $16,096,500,000.00 in Sulfuric acid sales (minus shipping) in that time @ 75 dollars per ton H2S04. (Or a multiple of that in fertilizer sales) They indulged instead in a long term program of false economics, that delivers markedly inferior pollution abatement, seemingly out of vanity alone. The same sort of attitude prevented them from taking a royalty in Timmins' richest gold mine, the Kinross 1060, because it would have meant giving a royalty to their arch-rival, Falconbridge.
EC<:-}