Garpenberg plant in Sweden benefiting from successful application of Model Predictive Control to a complete flotation circuit
Baden, Switzerland, November 18, 2009 – ABB, the leading power and automation technology group, announced today that it has successfully applied ABB’s award winning Expert Optimizer solution to the zinc flotation circuits of Boliden’s Garpenberg plant in Sweden. The solution applied Model Predictive Control (MPC) to help to stabilize the overall process, and maximize zinc revenue.
Boliden is a leading European metals company whose core competence is in the fields of exploration, mining, smelting and recycling. Boliden´s main metals are zinc and copper. Other important metals produced include lead, gold and silver. Boliden’s business concept is to extract minerals and produce high-quality metals in a cost-effective and environmentally friendly way, and to exploit the commercial opportunities that the market offers, thereby creating value for its shareholders. ABB and Boliden have a long track record of successful collaborations in the field of automation technology.
In this framework, ABB and Boliden agreed to collaborate on a project to achieve a successful application of Model Predictive Control (MPC) to a complete flotation circuit. The aims were twofold. Firstly to stabilize the process in spite of external disturbances, such as ore quality changes. Secondly, the zinc revenue should be maximized, through zinc recovery and concentrate grade.
Successfully optimizing the circuit required that three criteria be met. First, the behavior of the process had to be predicted using a reliable dynamic model of the flotation circuit. Then cost functions and finally operating constraints were incorporated in order to produce a robust MPC application.
In order to achieve certainty regarding the controller benefits, a measurement campaign was started at the end of 2008 and finished in the middle of 2009. The results showed that concentrator efficiency (directly corresponding to revenue) was at least one percentage unit higher when MPC was used, compared with the existing manual control strategy. In addition, the zinc concentrate grade has been higher and more consistent, while the recovery has remained at the same level.
Mr Henrik Lindvall, Process Engineer at Boliden, Garpenberg, said, “Following the successful testing period, Boliden is continuing to use Expert Optimizer on their Garpenberg zinc circuit and has continued to report good results throughout 2009”.
Expert Optimizer, part of ABB’s cpmPlus suite of applications, is the advocated tool for implementation of advanced process control in general, and MPC in particular, for the mineral processing industry and others. In addition to the general framework for MPC, Expert Optimizer also includes tools for implementation of soft sensors and artificial intelligence applications.
ABB (www.abb.com) is a leader in power and automation technologies that enable utility and industry customers to improve their performance while lowering environmental impact. The ABB Group of companies operates in around 100 countries and employs about 120,000 people.