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cluding anodizing, etching, plating, stripping, decorative plating, and hard chrome plating.
It has fume control systems for use with chromic acid, trivalent chromium and hexavalent www.
chromium, and it advocates a different approach than mist-type systems.
“A packed bed scrubber with a Chevron mist eliminator will have a moderate chrome remo-
val rate,” the company states. “Using a mesh pad instead of a mist eliminator will increase the cfcm.ca
amount of chemical laden droplets kept from exiting the scrubber, yet neither of these designs
offer the high efficiency removal rate required by today’s air emission standards.” The CFCM Website
The majority of scrubbers, the company points out, function using adsorption, which Features:
involves the contact of a gas stream with an aqueous solution. However, due to the fact that
the chromium exists in the mist droplets, and not as a gas, the adsorption method is not News, Back Issues,
entirely effective. Buyers Guide,
“To properly scrub chrome,” Mech-Chem states, “mesh pads are used to create
separation of the chrome-laden vapor from the air stream on contact. By using these mesh Event Photos,
pads in a multi staged set-up, within a horizontal scrubber, chrome scrubbing efficiency People,
greater than 99 percent can be achieved.”
The mesh pads are considered key in chromium scrubbing due to their high removal New Products
rates of the metal, ability to handle moisture build up, resistance to being plugged, reduc-
tion of pressure drop through the scrubber and their ability to handle larger volumes of air for Finishing
laden with chromium-contaminated liquid. These factors, the company says, reduce both and Coatings
operating cost and overall maintenance of the system.
Tri-Mer Corp.’s offering in this market is a mechanical one. Its Fan/Separator is an Manufacturing.
all-mechanical, two-stage fume scrubber that can be used for sulfuric acid pickling, metal
plating, and battery charging operations. It therefore includes chromium fume control in Check it out Today
its portfolio of applications.
The scrubbing liquid wets the contaminant as it enters the fan, allowing it to be centrif- and Every Day!
ugally spun out of the fan scroll through dynamic mixing. The centrifugal action, using the
fan wheel as part of the scrubbing process, eliminates a reported 55 percent of all airstream
contaminants. The scrubber has dynamic scrubbing as its first stage and impingement as
its second stage.
The impingement process causes the air to change direction as it passes across the rigid
packing media. The packing media also act as a mist eliminator section.
It is supplied in framed packs and provides a claimed 99 percent removal efficiency of
20 micron and larger liquid droplets under a continuous duty load. Contaminants enter the
eye of the fan where they are treated with a fog mist of scrubbing liquor.
The system is claimed to operate with 20 percent less brake horsepower than conven-
tional fume eliminators. The fume scrubber’s high efficiencies are possible, Tri-Mer says,
due to its unique use of the fan as a centrifuge in the scrubbing process.
Fan velocity is precisely controlled so that air crossing the rigid packed media stays
within design parameters. The system is positively pressured, working in a manner that is
the reverse of conventional “negative air” scrubbers. Thus, air is pushed, rather than
pulled, through the system.
Tri-Mer says 55 percent of the system’s performance results from contact between the
contaminant-laden air and the rigid tube packing, while 45 percent is from the centrifugal
action of the fan wheel. The unit is said to be extremely effective in eliminating corrosive
contaminants, and the outlet is near saturation. Total energy consumption is reportedly 15
to 20 percent less than comparable wet scrubbers with a negative pressure design. Please send all your News,
The Tri-Mer fume scrubber was engineered for simple installation and start-up, New Products to Theresa Rogers

so start-up costs are said to be low. Fan/Separator units are manufactured of PVC, theresa.rogers@cfcm.ca
polypropylene, stainless steel or mild steel. Tri-Mer will select the appropriate material For Advertising Please Contact
for each application. The company also designs and manufactures duct systems in PVC, Gillian Thomas 1-416-277-1269
polypropylene and fiber-reinforced plastics. gillian.thomas@cfcm.ca
All scrubbing systems need to be configured on a custom basis, with no two anodizing
plants being alike. The accumulated knowledge that major suppliers now have from
decades of experience might not guarantee a perfect solution, but the problems of emis-
sions control are improved every year as the technology advances. n

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