Tiwest follows the 'reduce, reuse, recycle' philosophy at all of its operating sites.
Chandala's residue management plant treats all the process residue streams on site. These are neutralised and solids precipitated and filtered, prior to return to Cooljarloo, along with process residues from the Kwinana operations, for disposal in specially constructed clay lined cells that form part of the rehabilitation process. The clear process liquors collected during filtering of the waste stream at Chandala are returned to the synthetic rutile plant for re-use.
Tiwest has established programs to continually increase the level of awareness of residue management processes so that each operating area understands the environmental impacts and key environmental risks that must be managed.
Activated Carbon
In an effort to minimise waste, Tiwest has created a sustainable by-product from its process operations at Chandala - activated carbon.
When turning ilmenite into synthetic rutile at its Chandala Processing Plant, Tiwest uses coal to heat the ilmenite, resulting in a combination of reduced ilmenite and a residue called char.
Previously char was returned to Tiwest's Cooljarloo mine site for incorporation in the rehabilitation process, however it is now separated to produce activated carbon which is packaged for sale in Australia and overseas.
Synthetic Rutile Recovery Plant
Tiwest has also reduced the amount of residue produced at its Kwinana Pigment Plant by capturing and recovering un-reacted synthetic rutile.
During its transformation into titanium dioxide pigment, synthetic rutile is mixed with petroleum coke and chlorine in a chlorinator. In the past, any unprocessed finer grains of synthetic rutile were discarded and disposed of with other residues from the plant.
The construction of a synthetic rutile recovery plant means even the fine grains are now collected and fed back into the process to be turned into more pigment.
The recovery plant means Tiwest has reduced feedstock losses by more than 6,000 tonnes a year, in turn producing more valuable pigment for the company and reducing the amount of residues returned to the Cooljarloo mine for disposal.