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FOR EFFECTIVE RINSING, THE QUANTITY OF RINSE WATER PER DM SQ

2004

I AM TRNATARAJAN , MANAGER COMPONENT MANUFACTURING RESPONSIBLE FOR METAL FINISHING , MAINLY PLATING , ELECTRO AS WELL AS ELECTROLESS NICKEL. OUR CORE ACTIVITY IS ZINC PLATING, VAT & BARREL.; OUR TOTAL AREA OF PLATING PER DAY IS

1. ZINC VAT................... 44,824.5 SQ DM

2. ZINC BARREL................

3 NICKEL PLATING.............

4 ALCROMATING................

5 BLACK OXIDISING............

OUR PRESENT WATER CONSUMPTION IS 15,000 LTRS PER DAY .WE HAVE ONLY STILL WATER SWILLS , DUMPED OUT TWICE A SHIFT. WE NEED TO KNOW IF WHAT WE CONSUME IN TERMS OF WATER QUANTITY IS NORMAL OR ABNORMAL. WE NEED TO KNOW WHAT LEVEL OF WATER SWILLING PER DECIMETER SQURE IS RECOMMENDED FOR A GOOD RINSE PROPERTIES.

T.R.NATARAJAN
IST TIER AUTOMOTIVE - COIMBATORE, TAMILNADU, India

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In our captive Zinc Plating shop (still bath), we plate around 450 sq.M of components every day. We are using around 10000 lits of fresh water everyday. Is there any specification for usage of water per square Meter of components being zinc plated? Is our usage of 10000 liters of water for 450sq.M of zinc plating normal? Kindly give your valuable views and suggestions.

M.KANAGAVEL RAJAN
1st tier automotive - Coimbatore, Tamilnadu, India
2004

Benchmarks for water usage stated in the European Commission reference document on Best Available Techniques for surface treatment are :- 50 l/m2 of treated surface area (scandinavia), 40 l/m2 of treated surface area (UK) and a regulatory limit of 8 l/m2 in France. The size of discharge will obviously depend on the type of work being plated. Flat surfaces will require less water than welded tubular assemblies for example.

Dougie Lightfoot
- Fife, Scotland
2004

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No offense to either side, but 40 compared to 8 begs the question of whether the French are five times smarter than the British or five times stupider :-)

The US decided in 1974 that 40 l/m2 was the right number, regardless of whether the part was a cup, a sheet, or a tube; and regardless of whether the plating was on vapor blasted steel requiring no prep at all, or on an aluminum casting requiring cleaning, etching, desmutting, zincating, stripping, re-zincating, and alkaline copper before the plating. So I guess Americans are either 30 years smarter than Indians or 30 years stupider :-)

We really do appreciate you help, Dougie, it's just that some of us spent nearly our entire careers under the cursed shadow of this ludicrous surface-area based "development document" that Dr. Leslie Lancy warned from day one would completely stymy efforts at pollution control. Decades later it still does, and it still won't go away, and I just can't quietly watch such ludicrous nonsense propagated worldwide -- countries copying a model that has been conclusively proved over the course of 3 decades to not work :-(

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2004

Having visited plating plants in France my thoughts are that 8 ltr may be the regulatory maximum but it certainly isn't what is achieved in practice. I'm on your side Ted regarding the curse of these reference documents. I just happened to have the information to hand as I'm currently working on an IPPC (Integrated Pollution Prevention and Control) permit application for our zinc plating plants. Yet another new regulation foisted on European industry by those who know better.

Dougie Lightfoot
- Fife, Scotland
2004