Reduction of Particulate Matter Emissions from Copper Concentrate Dryers at Caletones Smelter, El Teniente Division, Codelco

摘要

During the first half of 2018, the emissions of particulate matter from the stacks of copper concentrate dryers at Caletones Smelter have not met the exigencies required for the Supreme Decree 28, which begins to operate in December of the present year and states “The particulate matter emissions from Dryers and Slag Cleaning Furnaces must have a concentration lower or equal to 50 mg/Nm~3”. In case of non-compliance of this value, the corresponding dryers cannot operate until the concentration normalizes, restricting the total amount of smelted concentrate.To face this challenge, two approaches were evaluated: the determination of the optimal range of critical variables of the bag filters in order to obtain a particulate matter emission lower or equal to 50 mg/Nm~3, and a cause-root analysis focused on searching each cause that could contribute to high particulate matter concentration from the stacks. The latter was accomplished by one of the tools of the C+ methodology, known as Problem Solving, which comprises a meeting among the Unit Chief, engineers and operators of the process. This meeting is crucial in Lean Management because specific actions are defined to counteract the identified root causes, involving all the workers in the development and monitoring of the status of each action. After the partial implementation of the actions of the C+ meeting and the above mentioned technical analysis, a lower concentration of the particulate matter emissions was achieve in the concentrate dryers: from 67 mg/Nm3 in the dryer N°1 in May 2018 to 7.2 mg/Nm~3 in October 2018 and from average annual values of 200 mg/Nm~3 in the dryer N°3 to 23.2 mg/Nm~3 in October 2018. Hence, this tool of C+ has contributed to best environmental results in the Caletones Smelter, although there is more work to maintain these results.