bentonite
VOLCLAY® HPM 20 and Minerals Technologies Inc.
There are two different forms of bentonite—sodium (swelling) and calcium (non-swelling). It’s often called the mineral of 1000 uses. In commercial applications, it’s used “in foundry green sand binders, building waterproofing, cat litter, geosynthetic clay liners for environmental uses, iron ore pelletizing, drilling muds, edible oil clarification, animal feeds, and wine/juice clarification. Specialty applications of bentonite clay include asphalt emulsions, catalysts, cosmetics, paints and pharmaceuticals.” MTI makes little mention of the ceramics industry on their website, and no mention of it in their annual report, but the branded line, VOLCLAY ® HPM20, is what Laguna Clay Company receives. This product line from MTI is made for the metal-casting industry, falling the the “Performance Minerals” segment of the company.
MTI is a massive company, mining many raw materials, as well as drilling for oil and gas. Sustainability is of little to no concern. An excerpt from MTI’s 2021 Annual Report:
Enactment of climate-related legislation or adoption of regulation that restrict emissions of greenhouse gases in areas in which we conduct business could have an adverse effect on our operations or demand for our products. Our manufacturing processes, particularly the manufacturing process for PCC, use a significant amount of energy and, should energy prices increase as a result of such legislation or regulation, we may not be able to pass these increased costs on to purchasers of our products. We cannot predict if or when currently proposed or additional laws and regulations regarding climate change or other environmental or health and safety concerns will be enacted or adopted.
The Company is currently a party in various litigation matters and tax and environmental proceedings and faces risks arising from various unasserted litigation matters, including, but not limited to, product liability, patent infringement, antitrust claims, and claims for third party property damage or personal injury stemming from alleged environmental torts. Failure to appropriately manage safety, human health, product liability and environmental risks associated with the Company’s products and production processes could adversely impact the Company’s employees and other stakeholders, the Company’s reputation and its results of operations.
Public perception of the risks associated with the Company’s products and production processes could impact product acceptance and influence the regulatory environment in which the Company operates. While the Company has procedures and controls to manage these risks, carries liability insurance, which it believes to be appropriate to its businesses, and has provided reserves for current matters, which it believes to be adequate, an unanticipated liability, arising out of a current matter or proceeding or from the other risks described above, could have a material adverse effect on the Company’s financial condition or results of operations.
Mining
MTI’s mines are separated by the industry that they serve. VOLCLAY® HPM 20 serves primarily the metal-casting industry. MTI’s metal-casting mines are as follows: Lovell, Wyoming (American Colloid Co.); Gurulmundi, Queensland, Australia; Chao Yang, Liaoning, China; Tianjin, China; Yangbuk-Myeun, Kyeung-Buk, South Korea; and Enez, Turkey.
Wyoming is home to 70% of the world’s bentonite reserves and produces bentonite that swells up to 16 times its mass and absorbs 10 times its weight in water. Wyoming’s bentonite is mostly unique in this regard because of the presence of sodium, believed to come from the deposits of sodium from salt water. However, bentonite, primarily calcium bentonite, is also mined in Greece, Japan, Italy, Brazil, Romania, Germany, Mexico, Argentina, Spain, India, Hungary, Poland, Canada, Turkey, and Cyprus.
From the Wyoming Mining Association:
Bentonite is surface mined through a process called back-casting where reclamation is performed by filling the mining pits with soils from subsequent pits while the mine is in production. Typically the topsoil layer is about 30 inches deep, which is removed using heavy equipment.
Once the bentonite is removed, it is cleaned and then tested to confirm the grade. It is then dried in the field before being taken to the plant for processing and stockpiled on-site or transferred to a processing facility.
Refining
MTI lists their locations in their 2021 Annual Report, but don’t specifically mention refineries, simply “plants.” These locations are as follows: Belvidere, IL; Troy, IN; Shell Rock, IA; Albion, MI; Gascoyne, ND; Archbold, OH; York, PA; Chattanooga, TN; Neenah, WI; Colony, WY; Lovell, WY; Gurulmundi, Australia; Chao Yang, Liaoning, China; Tianjin, China; Chennai, India; Yangbuk-Myeun, Kyeung-Buk, South Korea; Laemchabang, Thailand; and Enez, Turkey. Again, these are only the locations that MTI has separated into the category of metal-casting.
From the EPA regarding bentonite processing in the U.S.:
If the raw clay has a relatively high moisture content (30 to 35 percent), the stockpiled material may be plowed to facilitate air drying to a moisture content of 16 to 18 percent. Stockpiled bentonite may also be blended with other grades of bentonite to produce a uniform material. The material then is passed through a grizzly and crusher to reduce the clay pieces to less than 2.5 cm (1 in.) in size. Next, the crushed bentonite is dried in rotary or fluid bed dryers fired with natural gas, oil, or coal to reduce the moisture content to 7 to 8 percent. The temperatures in bentonite dryers generally range from 900°C (1650°F) at the inlet to 100 to 200°C (210 to 390°F) at the outlet. The dried material then is ground by means of roller or hammer mills. At some facilities which produce specialized bentonite products, the material is passed through an air classifier after being ground. Soda ash also may be added to the processed material to improve the swelling properties of the clay.
Route
To see the possible routes that bentonite takes, click here.