On Friday, January 16, 1998, Bradenton, Florida, was deluged with rain.
Eight inches of torrential rain engulfed the region in 24 hours. Three of those
inches poured during an hour and a half. Many homes and businesses were
flooded, including Florida Anodizing & Coloring, Inc. Even though 12 inches of
water flooded the entire building, the company was in operation that Monday.
Fortunately, none of the tanks was affected, including the cleaning
tank. However, it may not have made much difference if the cleaning tank
had overflowed or leaked into the flood waters. Florida Anodizing does not
use highly alkaline or acidic cleaners. It uses a biological degreasing
system, which is a mild alkaline bath that operates at 115F with a near neutral pH
(8.8 to 9.1). This solution replaced an alkaline soak cleaner.
Prior to installing the cleaner, Florida Anodizing noticed that its
cleaner efficiency dropped off a couple days after makeup. This would force
operators to leave parts in the cleaning tank longer, backing up production and
leaving finishing tanks idle. Also, operators would need to constantly add
chemicals. Oil and grease would build-up and carry over into the etch and anodizing
tanks as well.
|
|
|
GRENADE CAPS before (left) and after (right) anodizing. |
The cleaning and etch tanks required dumping every three months.
An involved operation, it required five employees to work Saturday to dump
and treat the waste and make up a new bath. The total annual cost to dump the
etch and cleaner tanks was $12,000. To replenish the tanks cost an
additional $4,000; and the labor cost $1,500. Since installing the new bath, the cost
for maintenance is less than $1,000 a year, and the life of the etch tank
has increased fourfold. Sludge generated from the first six months of
operation rendered only one-fourth lb of non-hazardous residue.
Other benefits Florida Anodizing has realized are 50 pct increased
throughput and dramatically reduced rejects. Florida Anodizing finishes
numerous military parts, boat parts and parts for food preparation systems. Not all
parts are anodized. Some are plated with mid-phosphorus electroless nickel
from Chemco.
On one particular military part, the company used to run 10 pct rejects. If
the finish was poor after etching, the part could not be re-run, since further
etching would cause the precise threadings to go out of tolerance standards and
ruin the part. The parts used to soak clean for 20 min and go into the etch tank
for three min. Now the parts are cleaned in two to three min and etched in 15
sec without rejects.
Another part, a fitting, had to soak overnight to remove oil. The new cleaner removes it in three to seven minutes.
Other parts featured deep recesses that trapped oil. The parts would
appear clean and run through the anodizing line. After going through the anodizing
dye and sealer steps, oil would leak out, causing the color to run.
Florida Anodizing decided that to increase profits it would have to
increase throughput and lower rejects. So it started at the beginning with the cleaner.
The cleaning solution contains nonylphenol-free tensides. When parts enter the solution, tensides lift oil and impurities off the parts
and emulsify them into micro particulates that are then consumed by
micro organisms in the bath. The bacteria is safe for human contact and is
comparable to that used in the food, dairy and brewery industries.
|
|
SLUDGE generated after operating the cleaning tank six months. |
As the volume of oil increases, the organisms multiply in direct
proportion, maintaining optimal cleaning power. The micro organisms become
more effective as the oils emulsify.
The system is self-contained. It controls solution temperature, pH
levels and ten-sides. Automated sensors constantly monitor the solution for
Florida Anodizing, adding minute amounts of solutions required to maintain the
bath at optimum effectiveness. "The most maintenance I seem to do is dusting
off the equipment," quipped Al McNish, finishing supervisor.
Since installing the new cleaning bath approximately a year ago,
Florida Anodizing has not had to dump the cleaner. As mentioned, only one-fourth
lb of sludge has been generated. Throughput has increased 50 pct, since there
is no downtime due to idle tanks. The system has allowed Florida Anodizing
to increase business and profits and become more efficient. PF
