By Own Correspondent
VERMICULITE is fast replacing asbestos, with potential to redefine the country’s manufacturing and construction sectors owing to its key value propositions.
In applications where asbestos is used, vermiculite is coming in to replace minerals it has similar properties and functions.
As an inert, lightweight with high tensile strength, vermiculite is an insulator with poor heat conductor which comes in five grades that range from large, medium, fine, super-fine and micro grades.
In the construction industry, large vermiculite grade is used to manufacture light weight, heat resistant, plastering or ceiling boards, roof insulation, fire proofing and thermal insulation, low temperature insulation, noise reduction and plaster, sewage and effluent treatment, chimney linings and manufacture of brake linings for motor vehicles.
As a naturally-occurring geological material, more specifically a group of aluminium-iron magnesium silicates that closely resemble mica, vermiculite is found in the south eastern region of Zimbabwe. Buhera holds the second largest deposits of vermiculite in Africa at Shawa and Dinhidza mines, after Palabora in South Africa.
Zimbabwean vermiculite is most sought on the international market due to its high grade, equally comparable to reputable global suppliers.
Vermiculite also contributes to mining revenue, with export markets in America, Asia, Middle East, Australia, South Africa, while the European market chews up a bigger portion of Zimbabwean vermiculite.
It is important to come up with a varied product range that can value add vermiculite and benefit the local and regional markets so that it becomes useful in the construction industry.
The production process starts from mining, crushing, screening winnowing and finally baking. The production process is safe to the environment as the mineral is innate and sterile, with no hazardous chemicals used.
For the local market, raw vermiculite is being value added into exfoliated vermiculite which becomes useful in agriculture, especially horticulture where it acts as a soil conditioner used to retain the moisture, improve aeration, facilitates quick root growth and minimises the risk of diseases in plant. ENDS//