Construction World January 2016

CONSTRUCTION WORLD

JANUARY

2016

ENVIRONMENT AND SUSTAINABILITY

Blue Willow Aluminium has built an automated processing plant in

line with International Best Practice which is Hexavalent chromi-

um-free for environmentally-friendly pre-treatment manufacturing.

Recognised as a human carcinogen if inhaled, Hexavalent chromium is

also what infamously contaminated groundwater in Hinkley, United States,

leading to a lawsuit with a multi-million dollar settlement and the movie

‘Erin Brockovich’.

“We have built the first plant in sub-Saharan Africa that fully complies

with International Legislation and are proud to have created a processing

plant which includes the most environmentally advanced and technically

sophisticated chemical processes for preparation of architectural aluminium

prior to powder-coating,” said BlueWillow Aluminium GM, Schalk Pretorius

of the Atlantis Industrial plant.

“Our guaranteed quality comes from the constant reproducible

production standards generated by the automated system. Previously,

local companies had the frustration of irregular quality with high wastage

factors, and were forced to import and hold substantial stock to counter

the inconsistencies of local alternatives. Blue Willow Aluminium has filled a

growing need in the local market for access to world-class powder coating

technology, which results in aluminium of an equally high quality.”

The pre-treatment process begins with the production of ultra-pure

water, used throughout the process to provide a transitional medium from

one chemical process to the next.

All water fed into the system is used in the process, including the reverse

osmosis waste stream. Once the water has fulfilled its function through the

pre-treatment process, it is automatically treated and then re-utilized in the

garden irrigation system. “The process is so advanced the recycled water

is, in fact, cleaner than municipal water that goes into the pre-treatment

plant,” Pretorius said.

Aluminium pre-treatment is done in two chemical zones at ambient

temperature. The first zone deoxidises the aluminium by removing the

oxidised surface layer including all contamination contained with the

surface microstructure. The second zone forms a reaction layer with the

aluminium, providing galvanic protection, a layer for powder-paint to adhere

and, bare corrosion protection of the aluminiumwhile in transition after the

pre-treatment step to the final powder-coating process.

A FIRST FOR SUB-SAHARAN AFRICA

A Cape Town based company is the first in sub-

Saharan Africa to offer an environmentally-friendly

method of pre-treating architectural aluminium

prior to powder coating.

The green pre-treatment facility.

Nordston's most advanced powder coating facility.

Schalk Pretorius (right) MD of Blue Willow Aluminium, Shawn Williams

(wet chemical process technology partner), Jean van der Westhuizen

(technical director) and Heinrich Primic (sales director).

The powder coating system installed at Blue Willow Aluminium is the

most efficient and fastest colour change system available on the market -

Nordson’s most advanced system available globally. Offering absolute and

consistent process controls, the system incorporates the ColorMax Booth,

the Encore HD Application equipment, powder feed pumps and the Spec-

trum HD powder feed centre. “This state-of-the-art powder coating system

is truly cutting edge and completes Blue Willow Aluminium’s outstanding

service offering.”

Ultra pure water used in the pre-treatment process.