Utilization of wastewater from edible oil industry, turning waste into valuable products: A review

Valorization and Treatment of Oily Wastewaters From Agro-Industries Using Lipases: An Overview

“…Besides a high content of lipids, wastewaters from agro-industrial food processing, such as edible oil industries, generally have high chemical oxygen demand (COD), biological oxygen demand (BOD), total suspended solids (TSS), total dissolved solids (TDS), phosphates and sulfates (AHMAD et al, 2020;ASLAN et al, 2009;NWEKE;NWABANNE;IGBOKWE, 2014). However, the composition and the characteristics of oily wastewater vary between different industries and also between different batches in the same industry (AHMAD et al, 2020;NWEKE;NWABANNE;IGBOKWE, 2014). Thus, a proper characterization of the wastewater is necessary to determine which treatments and/or reuse/valorization processes are more adequate and feasible.…”

“…As methane is one of the end products of anaerobic digestion, anaerobic treatments can be applied in combination with biogas production, a biofuel that can be used by the industry itself (AHMED et al, 2015; KALAT; YÜCEER, 2017). In general, when compared to aerobic digestion, anaerobic systems have shown higher removal efficiencies, lower cost, and lower sludge production, besides enabling the conversion of waste to useful products (AHMAD et al, 2020;DOULA et al, 2017). However, anaerobic processes generally require longer retention times and larger surface areas due to slow startup (ALHAJI et al, 2016;STRONACH;RUDD;LESTER, 1986).…”

“…However, before thinking about the treatment of oily wastewater, the reuse and valorization of its components must be taken into account. Agro-industrial waste (including oily wastewaters) contains several valuable compounds that can be recovered, reused, transformed, and utilized in a variety of applications (AHMAD et al, 2020). The biotransformation of the oily wastewaters can generate commercially important products such as biofuels, surfactants, lubricants, organic acids, glycerol, among others (AHMAD et al, 2020;ANDLER;GODDARD, 2018).…”

“…Biological methods consist of the use of microbial metabolisms to transform complex and potentially toxic pollutants into harmless substances (YU; HAN; HE, 2017). Biological processes are classified according to oxygen demand into aerobic and anaerobic treatments that can be used alone or in combination(AHMAD et al, 2020). Aerobic treatments require the presence of oxygen and can remove a great fraction of the organic content of the oily wastewaters.…”

Advances in green processing of seed oils using ultrasound‐assisted extraction: A review

“…It is well‐known that oilseeds, as well as other seeds from by‐products of food processing, are an important source of oil (approx. 15%–50% of oil from the total seed mass), which are commonly used in the food and feed industry, cosmetic and pharmaceutic applications (Ahmad et al., 2020). From a nutritional point of view, the seeds are an excellent source of essential unsaturated fatty acids, in particular, omega‐3 (linolenic acid) and omega‐6 fatty (linoleic acid) acids, as well as others interesting bioactive compounds such as vitamins (E), phenolic acids, flavonoid, phytosterols, tocopherols, and carotenoid pigments (Hashemi et al., 2018).…”