Tailing Waste Management
The non-stop, quickening pace of industrialisation is quickly becoming the largest source of anthropogenic heavy metal pollutants. Anthropogenic pollution is a direct result of the influence of human beings on nature.
This environmental pollution is of deep concern due to its toxicity, threat to the environment and even the existence of all sentient and living things.
Examples of industries contributing to the rise of heavy metal pollutants:
- Electroplating & Metal Finishing
- Metallurgical Industry
- Chemical & Battery Manufacturing
- Mining & Mineral Processing
A couple of ways these industries cause this environmental pollution / heavy metal waste are:
- Acid Mine Drainage (AMD) – The run-off produced when water comes into contact with exposed rocks containing sulfur bearing minerals. This acidic run-off dissolves heavy metals (copper, lead, mercury) which pollute ground and surface water.
- Leachate – Contaminated liquid that is generated from water percolating through land and leaching out some of the constituents.
Interaction of Wollastonite with Acid Mine Water
In a recent university study of Wollastonite’s potential environment benefits, it was concluded that Wollastonite might be a useful first stage in the reduction of acidity and metal contamination.
A finding like this would be instrumental in the restoration of environmental damage caused by AMD (Acid Mine Damage). Restoration is achieved by reversing the damage created or stopping it completely. This can only be seen as an environmentally positive outcome.
How does Wollastonite achieve this? It is through incongruent dissolution which dissolves a mineral with decomposition or reactions in the presence of a liquid, converting one solid phase for another.
In this case, Wollastonite after a long term reaction with AMD solution pseudomorphically was replaced by a coated amorphous silica-rich phase. This significantly increases the specific surface area of the residual material. In sense, the AMD attaches to the Wollastonite, becoming a quartz-like mineral, turning the residual material (AMD) into a very useful carbon capture product.
An integral part of minimising the effects of global climate change is through long-term geologic storage of carbon dioxide (CO2). This is regarded as an integral part of moderating the concentrations of CO2 in the atmosphere.
Certain industries do inject subsurface CO2 but not at the rate and scale needed for true emission reduction. Due to the unprecedented amount required it is imperative to find a universally accepted solution.
To accurately create a geochemical process in the subsurface, experimentally derived data pertaining to mineral reactions between CO2, water and rocks.
Toxic Chromium Removal
The Earth’s crust consists of various forms of chromium. Hexavalent Chromium is a chemical compound that contains the element in the +6 oxidation state (thus hexavalent).
All chromium ore is processed via hexavalent chromium. It is essential to all materials made from chromium. It is used in textile dyes, wood preservation, anti-corrosion products and chromate conversion coatings. It also has various other niche uses.
Industrial uses include chromate pigments in: dyes, paints, plastics and ink. It is added as an anticorrosive agent in: paints, primers and other surface coatings.
In regards to the environment this is not a good thing at all. Toxicological studies conducted by environmental agencies worldwide have identified hexavalent chromium as a human carcinogen. Exposure to this toxic substance can lead to other health issues like intestinal ulcerations and dermatitis.
The structure of Wollastonite with its large, porous surface area, consisting of mainly silica and calcium oxide, make it an exceptional adsorbent.
Industries can utilize Wollastonite without adding overhead costs as a successful remediation tool in reversing or stopping damage to the environment.
Development of Agricultural Applications of Wollastonite
Agrinova – Final Report
The product has a neutralizing power and efficiency comparing it advantageously with current lime products. It also has appreciable levels of major and minor elements (Ca, S, B, Mg and Mn) essential for plant nutrition.
In addition, the scientific literature indicates that wollastonite has the ability to retain and fix soluble phosphorus. It also indicates that the material could be used in the manufacture of slow- mineralizating fertilizer. Another obvious benefit of wollastonite would be its availability of silicon for crops as studies show significant needs in this element for plants that are not filled with commercial fertilizers. Finally, a deeper interest in the product could come from the knowledge that silicon contributes to the strengthening of plant resistance to abiotic and biotic stress.
BCBD Cannabis Research
Wollastonite testing commenced January 20th, 2018 at BCBD’s Testing Facility, which features 5,500 square feet of indoor growing space with Phase one testing 198 cannabis plants.
Testing took ongoing measurements from four categories plus a control group. The four test categories of wollastonite consisted of testing the different grades:
Crushed small granular
Each was subdivided into two groups according to increments of enrichment to the base potting mixture.
Testing has shown that Wollastonite’s microfibres work as a matrix in MMC (Metal Matrix Composite). MMC is composite material with at least two constituent parts, one being a metal, the other material may be a different metal or another material such as ceramic or organic compound. In this case the other material would be Wollastonite. The matrix is basically a homogeneous and monolithic material in which a fibre system of a composite is embedded. It is completely continuous. The matrix provides a medium for binding and holding reinforcements together into a solid.
Wollastonite is effective in improving cement load behaviour, both pre and post peak.
Steel, Metal & Alloy Industries
Wollastonite has numerous uses in the steel, metal and alloy industries. It works as: a flux for welding, is a source of calcium oxide, a slag conditioner and even as a surface protector for molten metal during continuous steel casting.
When Wollastonite was used in conjunction with graphite results were impressive. Using the Wollastonite as a flux and the graphite as a reducing agent reaps the benefits of both. Wollastonite decreases the slag melting temperature and time viscosity. This causes slag-metal separation, but the addition of graphite, in content higher than optimum levels, alters the chemistry of the slag and stops the slag-metal separation from occurring.
Wollastonite in Manufacturing
Beginning in the 1980’s, Wollastonite has been used as a substitute for asbestos in products. Examples would be: plastics, paint, insulating boards/panels and roofing tiles. It is used in friction devices like clutches and brakes.
Wollastonite when used in ceramics, it reduces warping and cracking during the firing process. It also strengthens the finished product. For ceramic glazing mixes, Wollastonite adds much needed calcium.