Mine water pH adjustment
November 2010
System Integration & Control Systems Design
Mine underground water, process run-off and underground clarifiers and settling ponds suffer from pH difficulties. These arise from the different water uses and the characteristics of the different mining types. pH outside of the standard or ‘balanced’ range does not bode well for some flocculants and biocides and renders them ineffective. One mine in particular, outside of South African borders, was struggling with very low pH and control was limited to ‘throwing bags of lime into the clarifiers’. The problems arising from this were:
* Unstable pH complicated by pH bounce.
* Settling of the lime inside the clarifiers and hence not being distributed efficiently.
* Biocides are ineffective outside of their active pH range.
* Wastage of chemicals.
What was needed was on-line monitoring and controlled proportional dosing of a pH adjuster. Lime (alkali) being most effective for large-scale pH adjustment (to bring up the pH) would be the obvious choice. The solution sounds straightforward in principle; however, ProMinent discovered underground applications are more complex.
The pH measurement would have to be done three floors below the area for the lime dosing and make up. The make up system would have to be within the lime storage area, and the final lime dosing point would be in excess of 300 metres away. To further complicate the matter, there was no off the shelf lime make up system within the company’s range of products.
The solution, having assessed the system and complexities: a make up system based on the ProMinent flocculent make up system. The Ultromat type system makes up a solution proportional to flow and maintains the lime in a suspended solution. The pH measurement was achieved using 4-20 mA transducers to overcome the 300 m distances. The dosing was simplified using the ProMinent range of peristaltic with integrated VSD drives.
The result: a fully automated pH measurement, pH control, automated lime make up system and accurate reliable dosing all from a single source. The immediate benefits realised, were automated and accurate pH control, lower chemical costs and reliable disinfection from stable pH.
Further reading:
The state of the SI industry remains strong and is expanding
System Integration & Control Systems Design
The system integration (SI) industry is expanding with the adoption of AI, automation and data sharing, allowing companies to improve operational efficiency and competitiveness across diverse sectors.
Read more...
The symbiotic relationship between OEMs and SIs
Schneider Electric South Africa
Editor's Choice System Integration & Control Systems Design
While businesses tend to turn directly to original equipment manufacturers OEMs or vendors when embarking on IT projects, the role of the SI as a key facilitator and partner cannot be overstated.
Read more...
Flexible and precise dispensing technology
Beckhoff Automation
System Integration & Control Systems Design
The Scheugenpflug ProcessModule axis system forms the basis of Atlas Copco’s dispensing and screwing cells and a flexible integration platform for general contractors and machine builders. Precise process sequences are ensured by TwinCAT CNC and servo drive technology from Beckhoff.
Read more...
The time is now for systems integrators
Editor's Choice System Integration & Control Systems Design
Integrators combine sophistication regarding technology innovation with practical, hands-on experience. Collaborating with systems integrators is the means to significant productivity improvement, powered by the convergence of automation and information and operations technology.
Read more...
System integrators are a diverse market
Editor's Choice System Integration & Control Systems Design
System integrators (SIs) combine expertise on emergent technologies with real world experience. Working with SIs, it’s inevitable that at some point someone will say, “We’re not a typical SI.” And in many ways, it’s true. SIs come in all shapes and sizes.
Read more...
Avoiding the pitfalls of PLC and scada control system integration
Iritron
System Integration & Control Systems Design
Upgrading your control system by integrating PLCs with scada systems should be a simple seamless process. Regrettably, the industry is plagued with control system integration and upgrade myths and misconceptions that can lead to liability issues, project delays, cost overruns and decreased plant performance.
Read more...
EtherCAT measurement terminals for vehicle development at Mercedes-Benz
Beckhoff Automation
System Integration & Control Systems Design
At the Mercedes Technology Centre plant in Sindelfingen, Germany, car axles are examined with the highest precision on four test benches, in parallel with road tests and simulations. All data is acquired using PC-based control from Beckhoff.
Read more...
Loop signature 23: Tuning Part 2.
Editor's Choice System Integration & Control Systems Design
It is my opinion that most tuning methods are very crude. They do of course also offer a starting point for tuning if one is not fortunate enough to have a sophisticated tuning package like a Protuner around.
Read more...
PIC microcontrollers with integrated FPGA features in TME
System Integration & Control Systems Design
The new PIC16F131xx microcontrollers in TME’s offering from Microchip are ideal for the evolving and miniaturising electronic equipment market, offering efficient power management and predictable response times for controllers.
Read more...
Five smart machine trends you need to know
Adroit Technologies
System Integration & Control Systems Design
The last ten years have brought about dramatic advances in technologies that OEMs had never realised would affect their designs or the saleability of their machines, much less impact business models and profits so dramatically. The following discussion will cover key advancements and recommendations all OEMs should be adopting in their design processes to stay current and competitive.
Read more...
printer friendly version