Vermiculite Mineral Flotation
The hydrous phyllosilicate mineral, vermiculite, is geologically formed by weathering or hydrothermal alteration of biotite or phlogopite deposits. Raw vermiculite flakes have a micaceous appearance with interlayer water inside their structure. Vermiculite undergoes significant expansion and exfoliation when heated above 870° C. The exfoliation process occurs when the water flashes into steam and the flakes expand. This exfoliation effect is normally produced in large commercial furnaces, and the resulting lightweight material is chemically fire resistant and inert.
Vermiculite is used in agricultural, construction and insulation. It can absorb water for plant use and also liquids such as fertilizers, herbicides and insecticides, which can then be transported as free-flowing solids. Other uses of vermiculite include application in lightweight plaster and concrete, as thermal insulation and as a heat shield in automotive parts especially brakes.
Vermiculite mineral can be beneficiated using several different techniques. Lower-grade vermiculite mineral needs can be met with gravity separation whereas higher-grade vermiculite is primarily achieved using flotation. Flotation can be used to recover vermiculite of varying sizes and a two-stage flotation process can produce a range of grades for specific end uses. Often material is de-slimed, sized for flotation banks and conditioned with pH modifiers, water treatment additives, anionic collectors and frothers to optimize the flotation process. The vermiculite mineral is floated while gangue minerals are allowed to sink.
ArrMaz can conduct laboratory testing on your vermiculite samples to determine the best collector formula, operating conditions and flowsheet design for your ore. Our technical service representatives can help you run plant tests to evaluate reagent and plant conditions to maximize your vermiculite mineral grade and recovery.
Our mining chemicals are tailor-made for each customer’s unique ore and operational scenario, and are compliant with all applicable industry regulatory requirements. In addition to providing design consultation to vermiculite producers using our chemicals in their flotation process, ArrMaz’s expert field personnel are also available as process advisors to our customers’ engineers, production managers and operations personnel.