The Rockwell Automation Mequon site is a three-building complex with 571,000 square feet of facility space located on 48 acres of land in Mequon. Total employment levels are currently at 856 employees. The facility assembles and tests Ac and DC electronic drives and drive systems under both the Allen-Bradley and Reliance Electric product names. Key processes within the factory include placement of surface mount components, the automated insertion of through-hole components, wave soldering of printed circuit board assemblies, reflow soldering, light assembly and final test of drives and drive systems.
Previously, the ficility performed printed circuit board manufacturing activities. Part of the process uses a wave solder machine to secure components to circuit boards. The process used approximately 12,000 pounds of lead-based solder per year at a cost of approximately $37,000 per year. Simultaneously, the process generated approximately 8,700 pounds of waste solder dross per year. Although the dross contains a significant quantity of salvageable materials, it is unusable in its dross condition. Thus, dross was sent off-site to a recycler, and the facility received a credit from the recycler of approximately $3,650 per year.
Since there was a significant quantity of dross sent off-site and minimal recycling financial returns (compared to the initial expense), the environmental challenge was to discover a way to recover the usable solder from the dross while maintaining solder quality.
A solution to this environmental challenge was accomplished by a capital investment in a commercial solder recovery machine. The machine has the capability of recovering a significant quantity of usable solder on-site from the waste solder dross, thereby allowing material to be reused, as opposed to recycled.
By reusing solder on-site, the quantity of annual purchases was reduced by 48% from 12,000 pounds per year to 6,280 pounds per year. The amount of solder dross sent off-site to a recycler was reduced by 53%, from 8,700 pounds per year to 4,080 pounds per year. Additionally, the use of the solder recovery machine reduced wave solder cleaning time by 33%. The payback period was calculated to be less than 11 months. However, what proved to be more important was Rockwell Automation's decision to switch to lead-free solder in 2005. The lead-free solder will contain silver and be significantly more expensive. After the solder change occurs, the ability to recover solder on-site will become more important from a financial perspective, in addition to the environmental reasons.
Corey Peterson, General
Supervisor, Electronic Processes
Nominated by: Tom
Frost, Senior Environmental Engineer, Rockwell Automation - Mequon