Waste preventing technologies

["Ralph E. Cooper" <rec3@po.cwru.edu>]

Bob asked about waste prevention.  I worked with a plating shop that was
using huge amounts of water and producing a large wastewater stream that
required treatment and produced a sludge that was hazardous waste.  In
addition, the chemical tanks used in the plating had to be changed out
relatively frequently, due to contamination carried into them from the water.

By adding tanks to the system for multiple counterflow rinses, and for
pre-rinse of plating parts with used chemicals (rather than disposing of
them), we were able to:
        1.  turn the water flow in each rinse step to fractions of a gpm.
This allowed use of RO water in the rinses (now economically feasible).  The
use of RO water improved quality and resulted in extended life of the
plating tanks.
        2.  take the outflow from each rinse step and use it as make-up
water into the plating tank.  This eliminated the wastewater stream, the
sludge and the hazardous waste.

The effect was to eliminate a wastewater and sludge stream, extend the life
of the plating tanks substantially (5-8 fold increase in useful life),
resulting in less disposal of spent plating chemicals, all with an
improvement in quality, a slight increase in productivity.  The bottom line
savings for the plant were measurable in $10Ks per month; payback period was
less than 2 years, counting all disruption, capital, engineering,
consulting, etc.  Energy use was essentially constant, substituting
wastewater treatment energy (water handling and sludge dewatering, etc.) for
additional water handling cost in the plant.

Old technology, old application, new eyes and ideas.

Ralph

Ralph E. Cooper, Ph.D.
J.D. Class of 1999
3598 Glencairn
Shaker Heights, OH 44122
e-mail:	rec3@po.cwru.edu
Voice:	216-991-6837