Hydrometallurgy: The Superior Technology

For years the nickel industry has relied on pyrometallurgy to extract market-quality metals. Due to the length of time it has been used in this business, it is known as a proven technology for processing plants not only in Canada but also around the world. Hydrometallurgy, on the other hand, is a newcomer in the field and  has already proven its ability over pyrometallurgy due to its many advantages.

Hydrometallurgy or hydromet, for short, provides many economic, environmental, and labor benefits. By using only one facility as opposed to the two needed in pyromet makes hydro economically sound. Pyrometallurgy  is a two-step process wherein the concentrates from nickel, copper, and cobalt sulphide ores have to be smelted in a smelter first. The second step involves refining the matte in order to produce market-ready metals—a step which is done in a refinery. Hydromet, meanwhile, simply dissolves the metals in an aqueous chemical solution at lower temperatures, processes, purifies, and recovers them in a single facility. Essentially  mining plants could reap huge savings being derived from constructing only one facility instead of two.

There is also a reduction in cost in the daily operations that is associated with only having one processing plant. Energy consumption is significantly reduced when there is only one facility to maintain and where room temperature is needed to extract the metals. Both these factors contribute to the efficiency of the process. This is definitely not the case with pyrometallurgy where up to 1200 degrees Celsius of energy is needed to bring about the extraction of metals.

Also Pyrometallurgy, cannot compare with the environmental benefits of hydromet.  Unlike pyromet, hydromet does not produce emissions of strong and noxious gases like carbon dioxide, sulfur dioxide, and dioxins that are hazardous to earth and humans. The hazardous gases produced in hydromet cannot escape into the air but are treated chemically. Take sulfur as an example. In hydromet, it remains in its stable form and is not released in the air as toxic sulfur dioxide the way it would be with the use of pyrometallurgy. As far as the final residue is concerned, hydromet produces only solid waste components like mixed plastics which can be reused or recycled. This is not the case with pyromet where the recovery potential is very low for the slag, dusts, and metals that result from its process.

The labor force also benefits. Workers using Pyrometallurgy are manning the furnaces to high temperatures and hard conditions. Hydromet, meanwhile, does away with the smelting part of the procedure and thus produces a worker-friendly workplace that’s cleaner and cooler. Hydromet is also the runaway winner when job creation is concerned. The processes it employs are labor-intensive and will thus require the hiring of more workers from construction to operation.