Crane Ridge Ltd.
Leading by Example
Introduction
As Crane Ridge has provided Consultancy services across the industry, we have seen the need to find a practical way to apply our beliefs and technical know how to help make mining more sustainable, greener and have its own justification. Because of this, we have identified the need by mining companies to include for downstream beneficiation. Most mines as concentrate producers, have significant carbon footprint in the logistics of moving these concentrates around the world to its eventual smelting and refining destination. By using a modular, hydrometallurgical solution, we can not only eradicate the negative environmental impacts of smelting and refining, but that this has its own financial viability and justification. To do this, Crane Ridge has commenced as sponsor a project to establlish the first Green refinery in Walvis Bay, Namibia.
The Project
As a leading green base metal refinery, Critical Mineral Refineries Ltd. ("CMRL") is committed to enhancing sustainability, integrating innovative processes that reduce the environmental impact. Our eco-friendly policies continue to be at the forefront of our operation, while our state-of-the-art technology helps protect the environment and reduce our carbon footprint. As a company, we are passionate about staying ahead of the curve and using the latest technologies to produce sustainable products that meet the needs of our customers. Historically, concentrates containing metals sulphides and oxides are first subject to smelting or roasting to drive off the sulphur and reduce the metal into a leachable matte product. This matte product is then leached to recover the metals into solution, prior to refining and electrowinning or precipitation steps. The downside of this process is the production of SO2 gas, which when recovered, is converted to Sulphuric Acid (H2SO4). In many cases, this gas is not recovered and is emitted directly into the atmosphere. Impurities in the concentrate, such as Arsenic and Mercury are also volatilised in the smelter and end up as air pollutants. Carbon (C) in the form of coal is added as a reductant along with other fluxes to reduce the sulphide minerals first to oxides and then strip the oxygen atoms forming CO2 gas. Solid waste from the smelting process, slag, is stockpiled and contains other contaminants which over time dissolve into the ground water system. The capital cost of a Smelter is high, as is the capital cost of the Acid plant required to capture the SO2 gas. Electrical power consumed in these processes is expensive. The Green Critical Mineral Refinery project replaces all this smelting, acid capture and CO2 emission using an Ultra Fine Grind (“UFG”) and Pressure Oxidative Leach (“POX”).
The full development of the Green Refinery project requires US$ 3 million sponsorship or investment. To Date Crane Ridge has sponsored $115,000 toward this development.
