Winery Wastewater Treatment: Synergy Between Model and Experiment for Air Stripping Unit

abstract

en

Wineries produce large volumes of wastewater contaminated with ethanol, carboxylic acids, solids etc. Experiments with a multi-stage flash (MSF) evaporator showed encouraging results in the wastewater volume reduction. An obstacle to overcome is the high chemical oxygen demand (COD) due to the amount of ethanol present in the distillate stream. This work proposes a stripping unit as a solution and shows how to maximize the synergy of process modeling and experiments. The first experiment was designed using a preliminary model, while the experimental results confirmed the validity of the model and helped identify some potential improvements. The validated model showed the need to use the air at elevated temperatures in order to achieve sub-1,000 mg/l COD. This was confirmed by the second experiment when multiple passes through the experimental stripping column, higher flowrate (4,500 m3 air / m3 water) and an air temperature of 45 °C were sufficient to reduce COD below 1,000 mg/l.

Wineries produce large volumes of wastewater contaminated with ethanol, carboxylic acids, solids etc. Experiments with a multi-stage flash (MSF) evaporator showed encouraging results in the wastewater volume reduction. An obstacle to overcome is the high chemical oxygen demand (COD) due to the amount of ethanol present in the distillate stream. This work proposes a stripping unit as a solution and shows how to maximize the synergy of process modeling and experiments. The first experiment was designed using a preliminary model, while the experimental results confirmed the validity of the model and helped identify some potential improvements. The validated model showed the need to use the air at elevated temperatures in order to achieve sub-1,000 mg/l COD. This was confirmed by the second experiment when multiple passes through the experimental stripping column, higher flowrate (4,500 m3 air / m3 water) and an air temperature of 45 °C were sufficient to reduce COD below 1,000 mg/l.

winery wastewater, chemical oxygen demand, air stripping, process modeling, ethanol

06.02.2022

University of Thessaly

Volos, Greece

2653-8911

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