Treatment and valorisation of winery wastewater by a new biophysical process (ECCF®)

Abstract

Taking account of the high specificity of the organic load of winery effluents, a new biophysical treatment using the stripping of ethanol combined with a final concentration by evaporation has been studied. Two options are proposed: full treatment and pre-treatment. The study of the composition of winery wastewater has shown the large, dominant part of ethanol in the organic load (75 to 99% of the COD). According to a linear correlation between COD and ethanol concentration, the determination of ethanol concentration can be used to estimate the organic load of winery wastewater. Full treatment by stripping and concentration at a pilot plant allows the separation of the wastewater into highly purified water (COD elimination > 99%), a concentrated alcoholic solution usable as bio-fuel and a concentrated by-product. Stripping alone represents an advantageous pre-treatment of winery wastewater. The purification rate reaches 78 to 85% and ethanol is recovered. The process facilitates discharge into a sewage system in view of treatment with domestic effluents and can also improve the efficiency of overloaded or old purification plants. The economical approach of this method demonstrates its competitiveness in comparison with biological treatments: low energy consumed, no sludge.

An Annual and Seasonal Characterisation of Winery Effluent in South Africa

“…These results are in agreement with data from Colin et al (2005), who found that ethanol was the main organic component of winery effluent.…”

“…This measurement is discussed in Methods. The COD of the effluent peaked in mid-March (which is mid-harvest) and decreased for the rest of the year; this is in common with the findings of others (Malandra et al, 2003;Sheridan, 2003;Colin et al, 2005). The maximum concentration found (3800 mg/L) is also in the expected range for a cellar of this size (Sheridan, 2003).…”

“…No glucose was detected in any of the samples tested over the course of this study, although other authors (Malandra et al, 2003;Colin et al, 2005) found both fructose and glucose in effluent samples.…”

“…The ethanol concentration ranged from not detectable (indicated as 0 mL/L) to 1.7 mL/L, which is approximately one third of that found by Colin et al (2005). Although propanol was defined as an abundant component on the basis of the initial characterisation, it was not detected in any of the samples of this particular winery effluent.…”

Influence of Winemaking Practices on the Characteristics of Winery Wastewater and Water Usage of Wineries

“…Ethanol concentrations of 4 900 mg/L and sugar (glucose and fructose) of 870 mg/L were detected in winery wastewater with a dissolved COD of 12 700 mg/L (Table 7). In addition to this, a study by Colin et al (2005) showed that there is a linear correlation between COD and the ethanol concentration, and therefore the organic load of winery wastewater can be estimated when the ethanol concentration is known.…”