ENGINEERING FOR FIRE AND EXPLOSION PREVENTION SYSTEM IN DUST COLLECTOR UNITS AT A LEAD SMELTER (GA4)

ISSUE

A lead smelter experienced regular hostile fires and explosions in their crucible dust collector units. These events were detrimental to the environment and workers’ health and safety.

TECHNOLOGICAL CHALLENGE

The classical solution to solve this kind of problem has been the installation of spark detecting and fire extinguishing systems. However, for the lead smelter, such solution would have required an investment in capital (CAPEX) of approximately 1,4 M$. This level of expenditure could not be justified by the plant management and they were looking for alternate solutions.

RECOMMENDED SOLUTION

STS Canada's specialists were thus called to evaluate the problem and design a customized solution that meets the client’s needs and budget. STS's strategy was first to investigate the cause of the fires and explosion to find and deal with the source of the problem. After a thorough analysis, STS recommended the installation of a flame-retardant powder injection system (injecting hydrated lime) to protect the filter bags and make them nonflammable. The proposed system is compliant with CNESST (Québec Health and Safety) and NFPA regulations for worker’s safety.

RESULTS

The system is compliant with CNESST (Québec) and NFPA regulations for worker safety. The project was integrated to the smelter's operation in 2009 and has since required no additionnal labor. Since then, two fires have erupted in the crucibles and were properly managed by the fireproofing system. The total cost of this system was 75% of the traditional one aforementioned. Moreover, it has significantly reduced the amount of dust sent out into the environment.