Different Trends for Mining and Processing Titanium
The current costs of titanium have nothing to do with the rarity of the material. In fact, it is an extremely abundant metal with workable deposits all over the earth. The costs come directly from the resources, time, and energy required to mine and process it. Titanium is valued for its high strength-to-weight ratio, its ability to withstand high temperatures, and a strong corrosion resistance. It is already used throughout the medical, marine, and aerospace industries, but if the current trends continue, the price may come down far enough that it will be used in a wide range of other industries.
Mining in general is getting more expensive because of the amount of labor required and the various compliance regulations. Titanium metal is normally strip mined (open pit mined) and sent, soil and all, to a processing center where the ore can be extracted. This is possible because of the abundance of the metal in the earth, but once it reaches the processing phase, things get difficult.
Processing the Ore
Processing titanium, or separating the desired materials out of the metal, has to take place before any of the machining or manufacturing. The most common way to do this is through the Kroll Process – something that was first introduced in the 1930s. Since then, there really hasn’t been anything to replace the slow and inefficient process, and more than 95% of titanium product still uses this method.
This process involves combining the titanium oxide ore with chlorine to make titanium chloride. A lot of other metals can skip this step, but titanium can’t be processed without it (which is one reason it requires more time and money). It can then be reduced using magnesium or sodium inside a reactor that’s heated to 1,200C. This means that it must be processed in batches instead of a continuous flow through a blast furnace like aluminum or steel. The extraction process, in total, can take weeks for a single batch, and the largest reactors can produce about a ton of titanium a day.
In order to bring the costs of titanium production more into line with other abundant metals, current trends are looking for ways to equal or surpass the Kroll process. While nothing currently exists to work on the same scale as the current facilities, there are a number of alternatives that appear to have a lot of potential.
Mining in Canada
There are a couple processes in particular that are gaining some traction. The Armstrong and Fray-Farthing-Chen (FFC) Cambridge processes are getting closer to industrial implementation, and signs are pointing to lowered costs.
Both of these processes are based on using different mediums to inject a little electricity into the mix. The Armstrong process uses a flow of excess sodium while the FFC method uses a molten bath of calcium chloride. When the electrical current is introduced, oxygen from the titanium dioxide can be extracted and dissolved.
Until recently, this kind of electrolysis wasn’t an option for titanium. In other metals, like aluminum, this is possible because the input oxide and output metal are in liquid form and can effectively transfer the current. This mean keeping the metal in a liquid state – at a high temperature – and titanium’s melting point is too high to make that feasible. These new trends, though, use titanium in powdered form, directly from the industrial feedstock rather than titanium ingots. When it is mixed with the other agents, the electrical current can have the desired effect.
Finding Affordable Solutions
The industry is still a long way from turning these new methods into a usable process on a scale that will meet or beat the current standards. However, as technology and regulations continue to develop around the mining and processing of titanium, the costs may start to decrease and the metal will find a whole range of new applications in different industries.
About the author:
Frank Cusimano works for Titanium Processing Center. He is a knowledgeable figure in the titanium industry and appreciates the trends and movement that keep the trade interesting. His recent goal to provide valuable, relevant information about the industry has brought about a new passion for writing and all things titanium.