Hot galvanising is now the second most
used method, after painting, for protecting metal against corrosion.
The market for galvanisation is increasing at a constant rate of
about 10 % per year. One very significant problem for the hot galvanising
industry, however, is the production and release of considerable
volumes of dangerous by-products, mainly in the form of used acid
baths. The destruction of these effluents at approved centres is
among the highest budgetary costs in the galvanising industry.
This project concerned the development
of a process for recovering market standard iron chloride from waste
pickling and acid baths. The new concept is centred around a reorganised
non-polluting hot dip galvanisation workroom. Galvanisation bath
management has been completely reworked to obtain a production line
meeting the strictest environmental standards. The scouring solutions,
instead of being rejected, are valorised through transformation
of the iron-containing element which can then be used as a coagulant
in water treatment. Zinc recovery has also been optimised.
Project partners have been strongly urged
to continue and expand on their results and a second project is