It has long been observed in the laboratory that the pulp chemistry (ie pH, pulp potential (Eh), dissolved oxygen and oxygen demand) vary with changes in mineralogy, reagent additions and grinding environment. In the case of grinding environment, Magotteaux has extensive experience in making pulp chemistry measurements within a plant before and after a change in grinding media, and associating these differences with variations in metallurgical performance.
These measurements are collected using handheld laboratory instruments and are collected in short campaigns before and after the change in media. This technique, while valid, has limitations, and the question was asked: can this data be collected online and in real time? This led to the development of the Pulp Chemistry Monitor (PCM®). However, it quickly became apparent that measuring these parameters is only part of the story.
Measuring is NOT enough! The data must be processed into a form that provides value to the plant by either improved reagent utilisation and/or delivering better metallurgical performance. To this end, a PCM® was installed on the Jameson Cell feed at Prominent Hill in December 2018. The pulp chemical data generated was married together with other plant parameters to build algorithms for concentrate grade and recovery control. Subsequent step testing of the Jameson Cell collector, air and pulp level showed that the algorithms were able to predict changes to the Jameson Cell copper concentrate grade and recovery as these parameters were varied. This suggests that it would be possible to employ the algorithms to control the Jameson Cell flotation behaviour dynamically. This hypothesis was tested in a short ON/OFF trial. The paper discusses the results of the step testing and trial using the algorithms to control Jameson Cell flotation.