Effectiveness assessment of olive mill wastewater treatment by combined process: Natural flotation and anaerobic‐aerobic biodegradation

Abstract

The present work intends to study the treatment of olive oil mill wastewater (OMW) by natural flotation followed by anaerobic‐aerobic biodegradation, without dilution. After natural flotation, turbidity, chemical oxygen demand (COD) and polyphenol decreased by 37.7%, 3.7% and 3.3%, respectively. Whereas, anaerobic treatment removed 23.9% of nitrate, 29.1% of turbidity and 16.2% of polyphenol. However, intermittent aeration treatment showed the reduction of nitrate, turbidity and ammonium by 90%, 26.5% and 65.1%, respectively. In general, the combined natural flotation and anaerobic‐aerobic treatment of OMW, without dilution, have led to reduced turbidity, COD, polyphenol, nitrate, ammonium and phosphorus by 67.5%, 29.1%, 25.2%, 93.9%, 77.1% and 81.8%, respectively. The germination index of the treated OMW was 69% after 30% of dilution. Finally, the proposed treatment process could be used in small and medium‐sized industries as a simple, economical and effective method. Also, the produced water could be reused for irrigation.

Study of the Pollution Generated by Wastewater from the Refining of Vegetable Oils

“…This constitutes the main environmental concern in developing countries such as Morocco [7][8][9]. The presence in significant quantities of any matter foreign to the water (solid, liquid, gas) could considerably impact the environment [10][11][12][13][14][15]. Indeed, vegetable oil refining industries are ranked as one of the primary sources of environmental pollutants [16].…”

Contamination reduction of vegetable oil refinery wastewater using innovative acid and basic chemical flotation processes

“…Vegetable oil re neries are one of the primary industries that often release toxic substances into the environment(Haddaji et al 2022). Simple compounds, such as phenolic alcohols, are hydrophilic, whereas high molecular weight polyphenolic compounds, characterized by a robust polyaromatic property, are generally hydrophobic (KhattabiRi et al 2021). Phenolic compounds such as curcumin at pH 3 are predicted to be the most hydrophobic(Zembyla et al 2018).…”

“…Applying otation as a pretreatment of olive oil washing wastewater removed only 5% of total phenolic compounds (Cifuentes-Cabezas et al 2021). Furthermore, the combination of natural otation and anaerobic-aerobic treatment of olive mill wastewater showed a 25.2% reduction in these compounds (KhattabiRi et al 2021).…”

“…found a removal e ciency of 30.4% nitrates and 95.9% phosphorus using coagulation-occulation as a treatment technique. In the combination of natural otation and anaerobic-aerobic treatment of olive mill wastewater, a 93.9% reduction of nitrates was reported (KhattabiRi et al 2021).…”