Wastewater Recycling

Case study - Encore tissue take a bow for saving water

Objective: To cut drinking water use by 50%, improve the quality and reduce the volume of trade waste discharged to the sewerage system.

How savings were achieved: Filtering wastewater from the tissue making process, making it suitable for reuse in the paper machine.

Technology used: Kadant Petax Fine Filtration System.

Water volume saving: 166 million litres per year.

Encore Tissue is a family owned Australian business operating in Melbourne since 1998. In 2003, a tissue machine was commissioned at the Laverton North site, where both recycled and virgin tissue grades are manufactured and converted into finished products.

The tissue making process uses either recycled fibre or virgin pulp which is mixed with water to create a slurry. The pulp
passes through several screens, where contaminants are removed and then further diluted with recycled water, before being
formed into a tissue paper sheet.

After drying, the tissue sheet is reeled into rolls of tissue paper. In the converting plant, these rolls are unwound and the sheet
is embossed, perforated and rewound on a core into toilet rolls or kitchen towel rolls. Finally, the rolls are assembled, wrapped
and stacked onto pallets before the finished product is delivered to supermarkets nationwide.

The tissue papermaking process requires large quantities of water to produce an evenly formed sheet of paper. Although the resulting wastewater from this process was of a relatively good quality, process water used by the tissue machine must
be free of solids, to ensure that fine cleaning sprays on the paper machine do not become blocked. The fine solids present
in the wastewater therefore made it unsuitable for this application.