classic | mobile
 

Search...

SA Instrumentation & Control Buyers' Guide

Technews Industry Guide - IIoT 2017

Technews Industry Guide - Maintenance, Reliability & Asset Optimisation

 

Advanced process control - APC: CSense intelligence improves smelter efficiency at Lonmin
July 2008, SCADA/HMI


An element of the smelting operation at Lonmin’s facility in Marikana involves drying platinum group metals concentrate through filtering and flash-drying processes. With platinum at an all-time high on world markets, production stoppages and inefficiencies could no longer be tolerated.

“The filter and drying section of the plant was identified as the bottleneck for the smelting operation,” says Frans de Beer, senior manager, Smelter. “We limited our furnaces accordingly because the concentrate could not be dried fast enough. Project leader, Kevin Hayes, did a black belt six-sigma project on the drying plant and another on the filtering plant but we could not get definitive results. Checking on the variances between these plants, however, showed that they were working against each other. This meant that we had to integrate the filter plant with the drying section.

“One way of doing this was to decouple them, introduce a storage facility and run them separately. Another was to introduce APC to effectively decouple them but to leave the plant unchanged. This was the preferred option and that is why we chose CSense.”

The overall control system objective was broken down into three parts, as follows:

* Optimal control of the hot gas generator (HGG) temperature.

* Optimisation of HGG fluidising damper control.

* Maximisation of flash dryer throughput.

Process overview: blue indicates the plant facilities now under CSense control and yellow indicates the control network
Process overview: blue indicates the plant facilities now under CSense control and yellow indicates the control network

HGG temperature

Poor control of the HGG temperature, a result of complex process dynamics, impacted negatively on flash dryer throughput as heat generated in the HGG was oscillatory and under certain conditions resulted in trips or the interruption of fuel feed. By implementing more stable temperature control these problems were eliminated, maximising both up-time and throughput.

luidising damper

Control of the fluidising damper was performed by the operator prior to APC implementation. It was shown that the damper was often operated sub-optimally resulting in either not enough, or an excessive amount, of heat being generated for the amount of filter cake available for drying.

Flash dryer throughput

“Controlling the temperature of the flash dryer was one of the main challenges as it is affected by the feed-rate as well as the moisture content of the incoming material,” says Percy French, automation manager, Smelter. “Another problem was having the filter section keep up once the flash dryer was properly controlled. So we looked at the data sets and started to build the control model, as described in the six-sigma project, and this served us well when implementing CSense.”

Prior to APC implementation, the operator would select the set-point for flash dryer feed rate based on expected available filter cake. Due to the small size of the filter cake reservoir this often led to either the bin running empty, which resulted in too high flash dryer temperatures that tripped the flash dryer; or the bin staying full, which held back filter production. Dynamic process models of individual equipment in the drying plant were extracted from historical process data. These models were then used to construct a dynamic plant simulation, from which an optimal APC control system was designed.

Benefits

* Production has increased from 16 000 tons/month to over 20 000 tons (although other factors have also contributed.)

* The initial claim was that CSense could improve production by 10% but the real number is well above that yet difficult to isolate precisely because of the interdependencies of the processes involved.

* Operators no longer have to worry about changing set-points and can focus on other problems.

* Incorrect temperatures due to bad control practices are a thing of the past.

* CSense was easy to integrate with the current control system and its rules can be changed just as easily by authorised end-users.

* By eliminating uncertainties, CSense has helped Lonmin to focus on the next level of productivity challenges.

In an increasingly sophisticated manufacturing and mining world, APC has become a differentiator between profit and loss, cognitive control and make-do control, predictability and trial and error. APC is a mechanism whereby the intellectual property of operators and process managers can be captured and refined to solve increasingly complex problems.

For more information contact Johan Rademan, CSense Systems, +27 (0)12 347 3110, johan.rademan@csensesystems.com, www.csensesystems.com


Share via email     Share via LinkedIn   Print this page

Further reading:

  • Yokogawa’s open scada solution
    June 2018, Yokogawa South Africa, SCADA/HMI
    Scada systems are typically used for supervisory monitoring and control of remote and geographically distributed assets through a more open platform for interfacing with several makes and types of equipment ...
  • Schneider gets smart with new HMI solution
    June 2018, Schneider Electric South Africa, SCADA/HMI
    In a world where quick access to data has become the key to efficiency, Schneider Electric South Africa’s latest innovation in the Magelis range of HMI solutions, Magelis GTU, allows users to create the ...
  • Scada Review 2018
    June 2018, Technews Publishing (SA Instrumentation & Control), SCADA/HMI
    The subject projects of this year’s Scada Review are a worthy reflection of the effort put in by the respondent end-users, SIs and vendors. It is encouraging to see that even in these times of economic ...
  • Scada review 2018: Adroit Technologies
    June 2018, Adroit Technologies, SCADA/HMI
    End-user details    Name: Raymond Bosch    Designation: Electrical foreman cold stores    Company: Two a Day Group    Phone: +27 (0)21 859 7666    E-mail: raymondb@tad.co.za       SI details    Name: Willie Cameron ...
  • Scada Review 2018: Wonderware
    June 2018, Wonderware Southern Africa, SCADA/HMI
    End-user details    Name: Jaco van Heerden    Designation: Project C&I Engineer    Company: African Rainbow Minerals Limited    Phone: +27 (0)11 518 4199    email: jaco.vanheerden@arm.co.za       SI details    Name:...
  • Adroit Scada validated as an IoT platform
    May 2018, Adroit Technologies, SCADA/HMI
    Last year, Adroit Technologies expanded its offerings through its partnership with Sqwidnet, the licensed Sigfox Internet of Things (IoT) network operator in South Africa. From the mid-March, Adroit has ...
  • HMI modular system for hazardous areas
    May 2018, Pepperl+Fuchs, SCADA/HMI
    HMI systems must satisfy the strictest requirements if they are to be used in explosion-hazardous areas. With this in mind, Pepperl+Fuchs has introduced a wealth of new developments for its VisuNet GXP ...
  • Water – the heart of growth and sustainable development
    April 2018, SCADA/HMI
    World Water Day is celebrated on 22 March and each year it highlights a specific aspect of fresh water. This year’s theme is Nature for Water, and it will be amplified through the South African Department ...
  • Fibre optic connector inspection system
    April 2018, Comtest, SCADA/HMI
    Comtest’s latest offering from AFL is the aeRos connected FOCIS WiFi2, the next generation fibre optic connector inspection system that uses an Android or iOS wireless connection for live image video ...
  • RS Components expands HMI portfolio
    March 2018, RS Components SA, SCADA/HMI
    RS Components has added a range of the most popular industrial automation devices from Pro-face to its extensive portfolio of HMI products, including 10 touch-displays from the GP4100 series and two touch-PLCs ...
  • Yokogawa releases enhanced ­version of Stardom
    March 2018, Yokogawa South Africa, SCADA/HMI
    Yokogawa Electric Corporation has announced the release of an enhanced version of the Stardom network-based control system. This version will include a new E2 bus interface module that has been developed ...
  • Scalable graphic terminals increase productivity in smaller applications
    March 2018, Rockwell Automation, SCADA/HMI
    Machine and equipment builders are already using tight integration between the HMI and controller to help increase productivity in large applications. With the new Allen-Bradley PanelView 5310 family ...

 
 
         
Contact:
Technews Publishing (Pty) Ltd
1st Floor, Stabilitas House
265 Kent Ave, Randburg, 2194
South Africa
Publications by Technews
Dataweek Electronics & Communications Technology
Electronic Buyers Guide (EBG)

Hi-Tech Security Solutions
Hi-Tech Security Business Directory

Motion Control in Southern Africa
Motion Control Buyers’ Guide (MCBG)

South African Instrumentation & Control
South African Instrumentation & Control Buyers’ Guide (IBG)
Other
Terms & conditions of use, including privacy policy
PAIA Manual





 

         
    classic | mobile

Copyright © Technews Publishing (Pty) Ltd. All rights reserved.