Stellar goes further with water and waste treatment plan

09 April 2013

Stellar Organic has long been at the forefront of pushing boundaries of both wine production and social initiatives which has led them to become one of the UKs leading ethical brands. Their latest developments include a water and waste treatment plan as they seek to implement best practice guidelines in the wine industry. (The Wine and Spirit Board’s Scheme for the integrated production of wine (IPW), 5th edition; July 2008.)

The cellar in Vredendal is relatively large and has the capacity to crush up to 20 000 tons of grapes in full production. The water used in the cellar comes from the Clanwilliam Irrigation Board via the canal system. Here's the extra steps Stellar has taken to ensure it meets its twin aims of recycling as much water as possible and optimising the quality of the wastewater that is used for crop irrigation.

Taking steps to eliminate chemicals

A new Hydrosmart water conditioner has been installed, which when used in conjunction with an Ozone generator, produces water with extra cleaning oomph that allows the cleaning of tanks in one operation and without the use of any chemicals that may leave residues in the water.

In some cases, mostly involving red wine tanks, stubborn residues may require the use of chemicals. The cleaning chemicals have been replaced with more environmentally friendly alternatives on the recommendation of IPW. Sodium hydroxide has been changed to Potassium Hydroxide and Citric acid has been replaced with Phosphoric acid.

Rinsewater from all tanks, whether chemicals are used or not, is sent to the wastewater treatment plant.

From solid waste to water for irrigation

The separation of solids within the cellar is done by hand and with the use of 5 mm screens. The water in the cellar flows through a rotary elevator, which is responsible for separating and depositing solids into a settling pond.

The liquid then stays in the pond beneath the elevator and excess liquid from the solid waste drains back into the system. The pond allows most of the solid particles to be removed from the water, resulting in cleaner water with a lower biological and chemical oxygen demand.

The wastewater overflows into two aeration tanks from the pond beneath the rotary elevator. The settling ponds are duplicated so that one can be cleaned while settling takes place in the other.

Overflow from the aeration tanks pours into the pond via a sump pump and is aerated before being pumped to the decanter. After the decanter has screened the water, it is used for irrigation.

No sewage water enters the wastewater system. The electrical conductivity is limited to the absolute minimum.

> Contact us
> Our Wines
> Back to News