Dear Mr. Sedlak: Could you kindly send me a copy of the article? Thankns in advance. >> >>At 11:24 28/10/97 -0500, you wrote: >>>Marie: >>> >>>We do not supply anything in waste treatment, but as a chemistry supplier, >>>we >>>are intimately involved in the issue. I advise you that the BEST thing >>>that >>>you can do to ease the issue, and cut costs is to separate your wastes, and >>>treat them in different ways. >>> >>>The presumption is that the only issues that you have in your waste water >>>are >>>pH and dissolved heavy metals. >>> >>>Most of the time you can separate your waste streams into the following >>>categories: >>> >>>1. Chelated, low, to neglible metal (rinses from resist strippers, alkaline >>>cleaners, etc.) >>>2. Chelated, high metal, (Electroless Copper rinse, and bailout, ammoniacal >>>etch rinse) >>>3. Non-Chelated, high metal (microetch rinse, electrolytic plating rinse, >>>etc.) >>> >>>On the first category, simple pH adjustment may be all that is required, do >>>this, and put it down the drain, if the metal is low enough, do not allow >>>the >>>chelates to mix with category three, or you jack the cost of treatment to >>>the >>>sky. >>> >>>Category three can best be treated by pH adjustment, and precipitation of >>>metal sludge. >>>Cheap and simple. >>> >>>Category two is the big expense, and if you mix all your wastes, all the >>>waste becomes category two waste. This must be treated by ion exchange, or >>>precipitation with special chemicals, like sulfides, or weird expensive >>>organics, to remove the metals from the chelates. >>> >>>This is pretty general stuff, but it is very often overlooked as a powerful >>>tool to assist and cut costs in waste treatment. >>> >>>If I can be of more assistance, contact me off line. >>> >>>Incidently, if you want to send me your fax number, I have an article on >>>chelates and waste treatment that you might find interesting. >>> >>>Best regards, >>> >>>Rudy Sedlak >>>RD Chemical Company >>> ############################################################## TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c ############################################################## To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TECHNET <your full name> To unsubscribe: SIGNOFF TECHNET ############################################################## Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information. For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311 ##############################################################