printer friendly version
Case study: Mogale Gold
July 2010, Control Systems Design
Mine tailings are the crushed and milled rock residue that remains after mineral extraction. These tailings must be deposited for storage in a cost effective way that also meets environmental guidelines and mandates. Dams, dumps, and other types of surface piling are some of the more common tailings deposition methods used today. However, these all pose serious environmental concerns, as tailings often contain trace and sometimes substantial quantities of the metals found in the host ore, as well as certain amounts of chemicals and compounds used in the mining processes. As a result, establishing and maintaining tailings dumps represent a significant cost for mining companies.
A New Strategy: Tailing reprocessing
Historically, mineral separation processes have been somewhat inefficient because after the required crushing, grinding and metallurgical treatment, some amount of valuable metal is left behind in the residue. But recently, improved mining technologies and the ever-increasing price of gold in the marketplace have opened the opportunity for mining companies to purchase old mining dumps and treat the tailings in order to recover residual gold. South African miner Mintails is currently focused on exploring, evaluating, and processing hundreds of millions of tons of surface gold bearing tailings in the Witwatersrand area of South Africa. These types of gold reclamation efforts are never 100% efficient, and automation and control plays a significant role in improving the metallurgical processes. With the help of systems integrator Opto Controls, each month Mintails is collecting significant amounts of the valuable metal. In the process, the company is positively impacting the environment by clearing away mountainous, land consuming, and unsightly dumps.
Opto Controls has been a supplier and integrator of hardware and software for industrial automation, remote monitoring, and data acquisition applications for more than 10 years. Specialising in solutions utilising Opto 22 components and systems, Opto Controls’ broad project and industry expertise includes access control and security, print production monitoring, and factory automation. Company president Mike Harrison and process control and programming engineer Adam Carless, head a team contracted by Mintails to assemble and configure an automation system for Mintails’ Mogale Sands Plant This system connects to, monitors, controls and acquires data from a large assortment of field devices, equipment, and instrumentation and also manages the many mechanical and chemical processes used to remove the gold from the tailings.
The Opto Controls system’s key components are Opto 22 rack mount and standalone programmable automation controllers (PACs) and I/O housed in containers located at various areas of a processing plant situated between the gold mine and the dump. “Initially, these controllers were to be networked via fibre-optic cable, but Mintails management later decided to go with a wireless solution from MikroTik so as to avoid having to dig trenches and lay conduit for the cabling,” explains Harrison. The MikroTik platform features a Linux-based operating system, omnidirectional antennas, and wireless communication capabilities utilising all four of the 802.11 standards (a/b/g/n), as well as frequency ranges within the industrial, scientific and medical (ISM) radio bands. The system also has meshing capabilities, data transfer speed of up to 350 Mbps, and a range that easily bridges the average distance (about 150 metres) between the Mogale site controllers.
Readers wanting to find out more about the Opto Controls solution architecture for the Tailings Processing System can visit: http://instrumentation.co.za/+C14002
For more information contact Mike Harrison, Opto Controls, +27 (0)11 792 5232, firstname.lastname@example.org, www.opto.co.za
- Dehn provides safety for automation systems
July 2015, Dehn Protection South Africa, Control Systems Design
Failure of automation systems, and the resulting drop in production capacities, can result in enormous costs for manufacturing companies. Therefore, high availability is critical for both measuring and ...
- Case History 142: Report after optimisation exercise – Part 3.
June 2015, Michael Brown Control Engineering, Control Systems Design
This is the third article taken from a report which was prepared for various departments in a process company after some optimisation work was performed for them. (The other two articles were published ...
- A sustainable star in South Africa
May 2015, Control Systems Design
Paper and pulp producer Sappi has been producing high-quality dissolving wood pulp at its Ngodwana mill in South Africa since 2013. Valmet’s unique dissolving fiber line concept resulted in a flexible and sustainable solution.
- Locally built spanner grinding solution is a winner
Technews Industry Guide - Maintenance, Reliability & Asset Optimisation 2015, Motion Tronic, Control Systems Design
Every machine builder’s dream is to make use of the latest technologies to design and build a machine from the ground up – to do something that has not been done before. Using a Kuka KR6 R900 Agilus Robot, ...
- Case History 141: Report after optimisation exercise - Part 2
April 2015, Michael Brown Control Engineering, Control Systems Design
The first part of a report, published in Case History 140 (February), showed successes obtained and problems uncovered in an optimisation exercise in a particular process plant that takes optimisation ...
- Something extra for everyone in Simatic PCS 7
April 2015, Siemens Digital Factory & Process Ind. & Drives, Control Systems Design
Version upgrade of field-proven control system brings higher efficiency.
- Honeywell to maintain control systems for Sasol
April 2015, Honeywell ACS South Africa, Control Systems Design
Assurance 360 program will provide ongoing services and support to Sasol synthetic fuels and chemicals plant.
- New modular control architectures offer potential to increase end user value
April 2015, Control Systems Design
With few exceptions, control architecture has changed little over the past 40 years. However, advances in processing power, network technologies and software, will enable greater value for end users in ...
- Four-channel analog output module
April 2015, ASSTech Process Electronics + Instrumentation , Control Systems Design
Jumo’s range of mTRON T measurement, control and automation systems now offer a new feature in the form of a four channel analog output. With its universal input/output modules and flexible connection ...
- Becker Mining expands CAS capabilities
March 2015, Becker Mining South Africa, Control Systems Design
Loco management system ensures operation of underground locomotives.
- Case History 140: Report after optimisation exercise
February 2015, Michael Brown Control Engineering, Control Systems Design
There is a particular continuous process plant in South Africa that takes base layer control loop optimisation extremely seriously. (Many other plants unfortunately do not, which to me is terribly sad.) ...
- Honeywell’s new alarm management technology
February 2015, Honeywell ACS South Africa, Control Systems Design
Helping to make plants and pipelines safer and more productive.