US 3,973,987 A · Water recycle treatment system for use in metal processing

Abstract

A water recycle treatment system comprising two main treatment sub-systems for treatment of contaminated water from a plurality of concentrated solutions and rinse baths to separate out the impurities therein. A first sub-system treats less concentrated solutions used for the rinse baths by channeling the flow therefrom to a first neutralizing tank which provides for pH control to produce a mixed output solution having a substantially constant pH factor, which is filtered to remove gross particles, the filtered solution being cooled in a holding tank and passed through a reverse osmosis process and carbon bed to produce clean water. The second sub-system treats highly concentrated solutions obtained from a plurality of chemical processes, mixes them in a second neutralizing tank which is utilized to produce a substantially constant pH output, which is fed to an evaporator to precipitate the metals and salts in sludge and also forms a water vapor output. The reverse osmosis waste is fed back into the second neutralizing tank and processed as noted above.

Claims8

Dependent claims

In a system for processing a metal workpiece such as a printed circuit board, having at least two or more separate chemical process solution bath tanks and rinse tanks through which the workpiece is passed, a technique for water treatment and reuse where the volume of water flow through the rinse tanks is at least nine times the volume of water flow through the chemical process solution bath tanks comprising the steps of:

providing a first flow path for contaminated water, comprising of a contaminating element including metal build-up derived from said rinse tanks and a second flow path for contaminated solution including metal build-up derived from said chemical process bath tanks;
treating the contaminated water in the first flow path to separate the contaminating element from said rinse tank contaminated water to produce clean water;
routing the separated contaminating element and the contaminated solution in said second flow path into at least one (a) common neutralizing tank wherein said contaminating element is neutralized;
separating the neutralized contaminating element and contaminated solution, to provide water vapor and sludge outputs;
and
pumping said clean water back to said rinse tanks and process tanks.

3 more elements

Dependencies are inferred from the claim text.

Water recycle treatment system for use in metal processing

Life of this patent

Water recycle treatment system for use in metal processing

Life of this patent

Abstract

Claims8