Community Research and Development Information Service - CORDIS

Reusing electroplating wastewater treatments

A Hungarian company has developed a wastewater treatment system for the electroplating industry that can significantly reduce capital processing overheads.
Reusing electroplating wastewater treatments
The electrochemical processes involved in electroplating technology mean that once the given objects have been coated, the water that is used as a medium is effectively contaminated. Thus as a result of electroplating, water becomes a two-phase contaminated solution and its solid contaminants need to be separated. This wastewater treatment system can function in either the batch, discrete or continuous processing modes and its capabilities are further enhanced by an automatic capacity.

For the periodic method, the wastewater is collected into receiving vessels whereupon they are placed into a reactor. The reagents are added, and then the treated water proceeds to settling pans where the liquid phase separates from the solid phase. This provides a solid phase of 20-30 percent concentration, with further dewatering in the sludge tanks yielding a solidification of approximately 90 percent. Following pH testing the solid free water passes through a rubble filter, an active carbon filter and finally a cation exchanger.

In the continuous method, the wastewater travels from the receiving vessels into the reactor where sensors measure the contamination levels and dispense the appropriate level of reagents. The wastewater flows into the settling equipment and as above it is separated from its solid contaminants. An additional optional function is the instalment of a sludge-drying machine, which can further enrich the sludge contaminant.

A re-circulation capability creates further reductions in initial rinse water demands, which in turn reduces capital processing overheads. This capability is enabled because the wastewater treatment process is so effective it actually removes all the contaminants. An additional aspect that should be noted is that this re-circulated water can be used in any bath for future electroplating processes.

Furthermore, this system can be fully automated with the reagent reservoirs supply being the only required physical intervention. If there is an error during any stage of the process and at any point, the computer system provides an error signal to the operators. With a fully automated process, re-circulating water processing and optimum sludge results, this wastewater treatment system should make any electroplating company very competitive indeed.

Related information

Record Number: 80977 / Last updated on: 2005-09-18
Domain: Environment