A winery that wastes no water is not beyond the realm of possibility. Using available technology, a winery water system is possible to reuses all winery water for irrigation, winery processes, sanitary applications and cooling water. While ground water (or even rainwater) is brought into the winery, it is recycled as much as practical and ultimately leaves the water system as irrigation, evaporation or sanitary water.
While still under design, preliminary systems have the following components:
Winery effluent is screened for solids which are routed to compost. The screened effluent is equalized for pH and flows to a membrane bioreactor (MBR). There, ultrafiltration membranes send clean filtered water to a surge tank. Solids from the MBR are also moved to compost.
At the surge tank, the disposition of winery water is determined. The water can be stored in a pond for future use as irrigation. Treatment with ultraviolet light sterilizes the water making it suitable for sanitary systems (toilets) and for winery processes such as tank and floor cleaning. The water can also receive further filtration through reverse osmosis.
Permeate from reverse osmosis (RO) is very clean and suitable for cooling water make up. Microbial growth is limited, even without cooling tower chemicals such as chlorine or bromine. Retentate from RO is high in solids. The stream is ideal for evaporation in a crystalizer. Solids are moved off-site while the liquid is essentially steam distilled water, ideal for cooling applications.
Zero liquid waste in not impossible. With ever tightening effluent restrictions and an overall shortage of the precious commodity of water, a forward thinking winery will install such a system in the not too distant future.