The Constancia copper-molybdenum project is located in the Andes in south-eastern Peru and is positioned 4,100m above sea level.
Ausenco provided Engineering, Procurement and Construction Management services to design, construct, and commission the 25 Mt/y concentrator and associated infrastructure for this high-altitude project. Ausenco also applied the ASM* guidelines for the project’s Process Control System.
Having the control system set up in this manner allowed the plant operator to be more efficient in diagnosing upset process conditions and pre-empt any potential issues. This enabled the plant to be operated more closely to its design limit, resulting in improved throughput and recoveries.
A feature of the Ausenco ASM control system is the design of the graphical interface. Instead of vibrant colours, as commonly seen in many control systems, those used on the graphics are drawn in pastel colours - referred to as shades of grey - with brighter colours reserved only for alarm conditions.
Alarm colours are single-purpose only, not dual-purpose as often seen in some plants - for example red/green used for on/off status as well as the alarm condition display.
As well as the use of colour, key process data trends are added to the graphics giving the operator a better understanding of the plant’s performance. Speedy access to information in this format provides the operator with the ability to foresee what the plant will be doing, resulting in more effective decision-making about the control of the plant. The uncomplicated layout of each graphic allows the operator to quickly see and access all key information, with the ability to ‘drill-down’ to lower level graphics if more detailed data is required.
Another feature is the high level of alarm suppression logic implemented ‘under-the-bonnet’, within the program. This smart alarming approach results in a manageable number of alarms for the plant operator to act upon. The goal is fewer than 1-2 alarms per hour in normal operating conditions and no more than 10 per 10-minute period in conditions outside the norm.
The platform used at Constancia was a Siemens PCS7, however Ausenco applies its ASM library and techniques to other commonly-used systems such as Rockwell and Schneider (Wonderware, Citect, Modicon) and Yokogawa.
Ausenco can apply these ASM techniques on any plant and if implemented properly, the improved operator response will result in reduced downtime, increased performance and improved safety.
*ASM - the Abnormal Situation Management consortium is a group of leading companies and universities involved with process industries that have jointly invested in research and development to improve process safety in the control operations environment.