Codelco’s Chuquicamata Division has three concentrator plants: A-0: conventional milling that dates back to the 1950s and has a capacity of 70,000 t/d. A-1: conventional milling plant dating from the 1970’s with a capacity of 34,000 t/d. A-2: semi-autogenous milling, which began operating in the late 1980s and has a capacity of 78,000 tons per day. The A-0 plant has equipment and processes that have been integrated and adapted to the requirements of different ores and increasingly lower grades. Among its main equipment are 13 bar mills that process 220 tph each and are fed through 26 feed hoppers (2 for each mill), which have a capacity of approximately 1.5 m3 each. These feed hoppers suffer plugging due to different causes such as: foreign elements, water supply cuts, increase in the flow and granulometry of the ore, among others. Although there are Tilt-switch type sensors, the plugging is not detected preventively and causes spills that damage motors and transmission elements of the bar mills.

Technological solutions are sought to detect and alert in a preventive way the possible occurrence of plugging in the feed hoppers of the bar mills. The scouting process could lead to identify and select suppliers for a supply or purchase process, whose scope will be defined according to the maturity level of the proposals that apply to the open innovation process, which could give rise to a pilot validation test, or to an implementation if they are relevant and meet the evaluation and selection criteria defined by Codelco.

• It must generate preventive alerts in case of potential plugging events, online and in real time.
• Minimal or no human presence for operation and maintenance.
• The proposed system and its components must have heavy duty characteristics, given the aggressive conditions of the environment (permanent particulate material, humidity, material projection and low visibility).
• The proposal should indicate the level of error or accuracy of the plug detection system.
• Low maintenance and calibration requirements, with high reliability and availability above 95%.
• Minimal modification of existing infrastructure for implementation (non-invasive technology).

The bar mill feed hoppers do not have effective systems to identify and alert in a preventive mode the development of an overflow event.

• Charge spills on mill motors causing damage to motors and transmission elements (pinion-crown) and equipment stoppage.
• Production losses due to stoppage of bar mills and replacement of components.
• Risk of accidents due to exposure of operating and maintenance workers.

Unexpectedly.

•  Tilt-switch type sensors that alert when the plugging has already occurred. Mill feed is stopped only to avoid prolonged load spillage.
• Visual inspection with on-site workers.

• Level sensors.
• Optical cameras, with no positive results for the presence of particulate matter.
• Vibration sensors in feed hoppers.

The following will not be considered in the background evaluation process:

• Advisories, consultancies or engineering studies.
• Solutions that require major modifications to the existing infrastructure.
• Solutions that consider changes in the flowsheet of the process or apply in previous stages to the feed hoppers.