BASIC ENGINEERING FOR THE TREATMENT OF FUMES EMITTED BY A SCALPER IN AN ALUMINUM CABLES PLANT (GA11)

ISSUE

A scalper is used for metal surface preparation in a wire rod and aluminum cable manufacturing plant. A thin layer of metal is removed while an oil emulsion is sprayed onto the hot metal parts. This step leads to the formation of very fine fumes (vaporization of the oil) and small metal chips.

While the metal chips are captured by a cyclone collector, the fumes still loaded with oils are directed to an HVAC ventilation unit and discharged to the stack of the plant. Although they are unharmful for health and the environment, the oils still present in the gases form a whitish plume at the stack which causes inconvenience for the neighboring community.

TECHNOLOGICAL CHALLENGE

To treat the gases upstream of the stack to reduce or eliminate the formation of the whitish plume from the plant stack. The objective is not a matter of environmental standard but rather to eliminate or reduce the stack plume for the benefit of the neighboring community.

RECOMMENDED SOLUTION

The proposed solution consists in adding, directly after the cyclone, a 3 stages coalescing filter allowing the successive removal of the metal particles, the coarser part of the oils and greases droplets and the fine oils and greases droplets present in the gas. The ventilation of the system is provided by a new fan to maintain the flow of gas.

RESULTS

The proposed coalescing filter has been installed and has allowed the capture of almost all fine droplets of oils and grease contained in the gas. Since the installation of the coalescing filter, the occurrences of whitish plume from the scalper ventilation stack have completely disappeared.