Circular Water Management Opportunities for Wineries Using Novel Thermal Process

abstract

en

Wine making is a water-intensive industry, with an estimated water footprint of up to 1,000 L per 1 L of wine. Most of the footprint is associated with irrigation, which essentially narrows the opportunities for circular water management to wineries. The water used by wineries, however, becomes highly contaminated with sugars, alcohols, carboxylic acids, etc. The organic loads of winery wastewater (WWW) are not only high, but also extremely fluctuating, e.g. chemical oxygen demand can vary by multiple orders of magnitude throughout a year. Wineries have limited possibilities to dispose the wastewater legally. An investment into their own wastewater treatment plant is frequently too high for the often family-owned small and medium wineries, therefore they are dependent on external facilities whose services are costly. Given these challenges and the growing legislation pressure, there is an increasing demand for cost-effective, robust and compact wastewater treatment technologies that would allow for water reuse and/or secondary products. One such technology, which is investigated in this work, is a combination of evaporation and stripping. Laboratory tests with real WWW from the Czech Republic have shown that the original wastewater volume can be reduced by 90 % using evaporation with the ethanol yield being virtually 100 % in the distillate. The distillate can be further processed in a stripping column to obtain recycled water with over 99.99 wt.% purity, with ethanol being either recovered or discarded based on the market situation. It was also demonstrated that the storage period affects the technology performance, therefore the storage time can be optimized to achieve specific technological goals. These promising results confirm that the innovative technology configuration has the potential to not only be competitive against the conventional WWW treatment technologies, but also redefine the water management in wineries by turning what was originally a waste stream into usable and/or marketable products.

Wine making is a water-intensive industry, with an estimated water footprint of up to 1,000 L per 1 L of wine. Most of the footprint is associated with irrigation, which essentially narrows the opportunities for circular water management to wineries. The water used by wineries, however, becomes highly contaminated with sugars, alcohols, carboxylic acids, etc. The organic loads of winery wastewater (WWW) are not only high, but also extremely fluctuating, e.g. chemical oxygen demand can vary by multiple orders of magnitude throughout a year. Wineries have limited possibilities to dispose the wastewater legally. An investment into their own wastewater treatment plant is frequently too high for the often family-owned small and medium wineries, therefore they are dependent on external facilities whose services are costly. Given these challenges and the growing legislation pressure, there is an increasing demand for cost-effective, robust and compact wastewater treatment technologies that would allow for water reuse and/or secondary products. One such technology, which is investigated in this work, is a combination of evaporation and stripping. Laboratory tests with real WWW from the Czech Republic have shown that the original wastewater volume can be reduced by 90 % using evaporation with the ethanol yield being virtually 100 % in the distillate. The distillate can be further processed in a stripping column to obtain recycled water with over 99.99 wt.% purity, with ethanol being either recovered or discarded based on the market situation. It was also demonstrated that the storage period affects the technology performance, therefore the storage time can be optimized to achieve specific technological goals. These promising results confirm that the innovative technology configuration has the potential to not only be competitive against the conventional WWW treatment technologies, but also redefine the water management in wineries by turning what was originally a waste stream into usable and/or marketable products.

Circularity; ethanol; evaporation; stripping; wastewater recycling; winery

25.07.2023

Girona, Spain

6th IWA International Conference on eco-Technologies for Wastewater Treatment: Conference Proceedings

269–269

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