There was a growing concern regarding the large amount of spent flux-thinner being generated from the wavesolder machine operation in manufacturing. This waste stream also contributed towards the company having to change its State Hazardous waste generator category from Small Quantity Generator (SQG) to that of Large Quantity Generator (LQG).
To address the problem, the company's process engineering group developed and began implementation of a source reduction project designed to control/eliminate spent flux-thinner. The project involved converting the wavesolder operation's flux application method from "foam fluxer" application technology to a more efficient "spray fluxer" application. The project was tied directly to the company's Source Reduction and Waste Minimization Plan in which calendar year 2000 was used as the "base year" for the new five year plan just written. In calendar year 2000, the spent flux-thinner waste stream accounted for approximately 85% of the site's total hazardous waste generation. The goal, at the time, was for a 50% reduction in total hazardous waste generation over the next five years during which time the plan would be in effect.
The project began by purchasing a fourth wavesolder machine in early 2001. The new machine featured the spray fluxer technology. Once the machine was tested and released to production, the plan called for retrofitting the remaining three wavesolder machines on a staggered schedule. A second wavesolder machine was retrofitted in latter 2001 and the last of the remaining two machines was converted in November 2002. Total project reductions were then realized at the end of calendar year 2003.
The wavesolder machine operation's reduction in hazardous waste generation was due primarily to the more efficient "spray fluxer" application. Because the older foam flux technology utilized a porous air stone for applying the flux to circuit card assemblies, the application method required the use of alcohol as a thinner. The flux-thinner mixture, pumped from a tank within the machine, was used continuously in the operation until the specific gravity measurement no longer allowed for its use. The resulting spent flux-thinner created the waste stream. The spray fluxer application does not require the use a thinner at all and, due to its higher viscosity, is able to be applied directly to the circuit card assembly with no spent waste generated.
Comments: Raw Material savings:
There was a 78% savings from reduced purchases of flux/thinner from the end of base year 2000 to the end of calendar year 2003 during the course of the project.
Disposal cost reductions:
There was a 30% reduction in total disposal costs from base year 2000 to the end of calendar year 2003 during the course of the project itself.