Analytical investigation of filter media clogging in a copper smelter’s dust collector (AA7)

ISSUE

A cooper smelter operates a baghouse dust collector handling process gas from a mineral dryer. The process gas contains dust, metallic fumes, moisture and sulphur dioxide (SO2). The dust collector had an operation problem with filter bags getting clogged very rapidly; this reduced the capacity of the whole gas handling system due to an excessive filter bag pressure drop. The plant contacted STS Canada to conduct the necessary analysis to find out the cause of this rapid clogging and to make recommendations to correct the problem.

RECOMMENDED SOLUTION

STS Canada analysed the physical and mechanical properties of new filter bags as well as three (3) used filter bags to find out the cause of the rapid filter media clogging. The results from these analyses have allowed STS Canada to identify the main cause of this problem and to make a recommendation to resolve the problem.

RESULTS

The filter media analysis revealed that after only a few weeks of operation, new filter bags were already severely clogged by fine dust particles trapped inside the pores of the media resulting in a significant loss of permeability. Based on these observations, STS Canada was able to recommend a preconditioning method for new filter bags to prevent clogging and chemical degradation of their filter media. These recommendations made it possible to maintain the dust collector's treatment capacity over time.