Treatment of Olive Mill Wastewater through Integrated Pressure-Driven Membrane Processes

The disposal of wastewater resulting from olive oil production (olive mill wastewater, OMW) is a major issue for olive oil producers. This wastewater is among the most polluting due to the very high concentration of organic substances and the presence of hardly degradable phenolic compounds. The systems proposed for OMW treatment are essentially based either on conventional chemical-physical, biological and thermal processes, or on membrane processes. With respect to conventional methods, membrane processes allow to separate different species without the use of chemicals or heat. This work deals with the use of the integrated pressure-driven membrane processes for the treatment of OMW. They consist of a first stage (microfiltration, MF) in which a porous multichannel ceramic membrane retains suspended materials and produces a clarified permeate for a second stage (reverse osmosis, RO), in order to separate (and concentrate) dissolved substances from water. Laboratory scale experiments with different small flat sheet RO membranes were first carried out in order to select the most appropriate one for the successive bench scale tests with a spiral wound module having a large membrane surface. The aim of this test was to concentrate the dissolved substances and to produce water with low salinity, chemical oxygen demand (COD), and reduced phytotoxicity due to a low content of phenolic compounds. The trend of the permeate flux and membrane retention as a function of the volume concentration ratio was investigated. The influence of OMW origin and its aging on the membrane performance was also studied.

Download Full-text

Enrichment of Phenolic Compounds from Olive Mill Wastewater and In Vitro Evaluation of Their Antimicrobial Activities

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2017/3706915 ◽

2017 ◽

Vol 2017 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Saleh Abu-Lafi ◽

Mahmoud Sami Al-Natsheh ◽

Reem Yaghmoor ◽

Fuad Al-Rimawi

Keyword(s):

Antioxidant Activity ◽

Phenolic Compounds ◽

Olive Oil ◽

Acid Value ◽

Antimicrobial Activities ◽

Olive Mill Wastewater ◽

Total Phenolic ◽

The Stability ◽

Olive Mill

The production of olive oil generates massive quantities of by-product called olive mill wastewater (OMWW). The uncontrolled disposal of OMWW poses serious environmental problems. The OMWW effluent is rich in several polyphenolic compounds. Liquid-liquid extraction of OMWW using ethyl acetate solvent was used to enrich phenolic compounds under investigation. Total phenolic and flavonoid content and antioxidant activity of the extract were determined. HPLC coupled to photodiode array (PDA) detector was used to analyze the main three phenolic compounds of OMWW, namely, hydroxytyrosol, tyrosol, and oleuropein. The antimicrobial activity of the extract was also investigated. Additionally, the OMWW extract was used as natural preservative and antioxidants for olive oil. Results showed that OMWW is very rich in phenolic compounds and has strong antioxidant activity. HPLC analysis showed that the extract contains mainly hydroxytyrosol and tyrosol but no oleuropein. The OMWW extract showed also positive activities as antibacterial (gram positive and gram negative) and antifungal as well as activities against yeast. The addition of OMWW extract to olive oil samples has an effect on the stability of olive oil as reflected by its acid value, peroxide value, K232 and K270, and total phenolic content.

Download Full-text

Olive oil enrichment in phenolic compounds during malaxation in the presence of olive leaves or olive mill wastewater extracts

European Journal of Lipid Science and Technology ◽

10.1002/ejlt.201600425 ◽

2017 ◽

Vol 119 (9) ◽

pp. 1600425 ◽

Cited By ~ 5

Author(s):

Konstantinos Kiritsakis ◽

Celia Rodríguez-Pérez ◽

Dimitrios Gerasopoulos ◽

Antonio Segura- Carretero

Keyword(s):

Phenolic Compounds ◽

Olive Oil ◽

Olive Mill Wastewater ◽

Olive Leaves ◽

Olive Mill

Download Full-text

The Valorisation of Olive Mill Wastewater from Slovenian Istria by Fe3O4 Particles to Recover Polyphenolic Compounds for the Chemical Specialties Sector

Molecules ◽

10.3390/molecules26226946 ◽

2021 ◽

Vol 26 (22) ◽

pp. 6946

Author(s):

Kelly Peeters ◽

Ana Miklavčič Višnjevec ◽

Esakkiammal Esakkimuthu ◽

Matthew Schwarzkopf ◽

Črtomir Tavzes

Keyword(s):

Phenolic Compounds ◽

Olive Oil ◽

Extraction Methods ◽

High Reactivity ◽

Polyphenolic Compounds ◽

Olive Mill Wastewater ◽

Beneficial Effects ◽

Two Phases ◽

By Products ◽

Olive Mill

Olive oil production using three-phase decanter systems creates olive oil and two by-products: olive mill wastewater (OMWW) and pomace. These by-products contain the highest share of polyphenolic compounds that are known to be associated with beneficial effects on human health. Therefore, they are an attractive source of phenolic compounds for further industrial use in the cosmetic, pharmaceutical and food industries. The use of these phenolics is limited due to difficulties in recovery, high reactivity, complexity of the OMWW matrix and different physiochemical properties of phenolic compounds. This research, focused on OMWW, was performed in two phases. First, different polyphenol extraction methods were compared to obtain the method that yields the highest polyphenol concentration. Twenty-five phenolic compounds and their isomers were determined. Acidifying OMWW, followed by five minutes of ultrasonication, resulted in the highest measured polyphenol content of 27 mg/L. Second, the collection of polyphenolic compounds from OMWW via adsorption on unmodified iron (II, III) oxide particles was investigated. Although low yields were obtained for removed polyphenolic compounds in one removal cycle, the process has a high capability to be repeated.

Download Full-text

Antioxidant Properties of Olive Mill Wastewater Polyphenolic Extracts on Human Endothelial and Vascular Smooth Muscle Cells

Foods ◽

10.3390/foods10040800 ◽

2021 ◽

Vol 10 (4) ◽

pp. 800

Author(s):

Anna Maria Posadino ◽

Annalisa Cossu ◽

Roberta Giordo ◽

Amalia Piscopo ◽

Wael M Abdel-Rahman ◽

...

Keyword(s):

Antioxidant Activity ◽

Cell Death ◽

Smooth Muscle ◽

Vascular Smooth Muscle ◽

Smooth Muscle Cells ◽

Olive Oil ◽

Vascular Smooth Muscle Cells ◽

Muscle Cells ◽

Olive Mill Wastewater ◽

Olive Mill

This work aims to analyze the chemical and biological evaluation of two extracts obtained by olive mill wastewater (OMW), an olive oil processing byproduct. The exploitation of OMW is becoming an important aspect of development of the sustainable olive oil industry. Here we chemically and biologically evaluated one liquid (L) and one solid (S) extract obtained by liquid–liquid extraction followed by acidic hydrolysis (LLAC). Chemical characterization of the two extracts indicated that S has higher phenol content than L. Hydroxytyrosol and tyrosol were the more abundant phenols in both OMW extracts, with hydroxytyrosol significantly higher in S as compared to L. Both extracts failed to induce cell death when challenged with endothelial cells and vascular smooth muscle cells in cell viability experiments. On the contrary, the higher extract dosages employed significantly affected cell metabolic activity, as indicated by the MTT tests. Their ability to counteract H2O2-induced oxidative stress and cell death was assessed to investigate potential antioxidant activities of the extracts. Fluorescence measurements obtained with the reactive oxygen species (ROS) probe H2DCF-DA indicated strong antioxidant activity of the two OMW extracts in both cell models, as indicated by the inhibition of H2O2-induced ROS generation and the counteraction of the oxidative-induced cell death. Our results indicate LLAC-obtained OMW extracts as a safe and useful source of valuable compounds harboring antioxidant activity.

Download Full-text

Intergraded Applied Methodology for the Treatment of Heavy Polluted Waste Waters from Olive Oil Industries

Applied and Environmental Soil Science ◽

10.1155/2011/537814 ◽

2011 ◽

Vol 2011 ◽

pp. 1-14 ◽

Cited By ~ 5

Author(s):

Antonis A. Zorpas ◽

Vassilis J. Inglezakis

Keyword(s):

Olive Oil ◽

Oil Production ◽

Olive Mill Wastewater ◽

Fenton Process ◽

Waste Waters ◽

Warm Climate ◽

Climate Conditions ◽

Integrated Method ◽

Third Stage ◽

Olive Mill

The annual olive oil production in Cyprus is in the range of 2700–3100 t y−1, resulting in the generation of significant amount of waste. The cocomposting of the olive oil solid residue (OOSR) and the treated wastewaters (with Fenton) from the olive oil production process with the application of reed beds has been studied as an integrated method for the treatment of wastewater containing high organic and toxic pollutants under warm climate conditions. The experimental results indicated that the olive mill wastewater (OMW) is detoxified at the end of the Fenton process. Specifically, COD is reduced up to 65% (minimum 54.32%) by the application of Fenton and another 10–28% by the application of red beds as a third stage. The final cocomposted material of OOSR with the treated olive mile wastewater (TOMW) presents optimum characteristics and is suitable for agricultural purpose.

Download Full-text

A focus on pressure-driven membrane technology in olive mill wastewater reclamation: state of the art

Water Science & Technology ◽

10.2166/wst.2012.506 ◽

2012 ◽

Vol 66 (12) ◽

pp. 2505-2516 ◽

Cited By ~ 15

Author(s):

J. M. Ochando-Pulido ◽

A. Martinez-Ferez

Keyword(s):

Olive Oil ◽

Large Scale ◽

Wastewater Treatment Plants ◽

Domestic Wastewater ◽

Olive Mill Wastewater ◽

Operating Conditions ◽

Added Value ◽

Wastewater Reclamation ◽

Starting Point ◽

Olive Mill

Direct disposal of the heavily polluted effluent from olive oil industry (olive mill wastewater, OMW) to the environment or to domestic wastewater treatment plants is actually prohibited in most countries, and conventional treatments are ineffective. Membranes are currently one of the most versatile technologies for environmental quality control. Notwithstanding, studies on OMW reclamation by membranes are still scarce, and fouling inhibition and prediction to improve large-scale membrane performance still remain unresolved. Consequently, adequately targeted pretreatment for the specific binomium membrane-feed, as well as optimized operating conditions for the proper membranes, is today's challenge to ensure threshold flux values. Several membrane materials, configurations and pore sizes have been elucidated, and also different pretreatments including sedimentation, centrifugation, biosorption, sieving, filtration and microfiltration, various types of flocculation as well as advance oxidation processes have been applied so far. Recovery of potential-value compounds, such as a variety of polyphenols highlighting oleuropein and hydroxytyrosol, has been attempted too. All this research should constitute the starting point to proceed with OMW purification beyond recycling for irrigation or depuration for sewer discharge, with the aim of complying with standards to reuse the effluent in the olive oil production process, together with cost-effective recovery of added-value compounds.

Download Full-text

Short-term effects of a low dose of olive mill wastewater on pomological characteristics of olive fruits and on oil quality: Olive oil quality is negatively affected by OMW application

2017 International Conference on Engineering & MIS (ICEMIS) ◽

10.1109/icemis.2017.8273074 ◽

2017 ◽

Author(s):

Meriem Tekaya ◽

Sinda El-Gharbi ◽

Imed Chraief ◽

Mohamed Hammami ◽

Beligh Mechri ◽

...

Keyword(s):

Olive Oil ◽

Low Dose ◽

Oil Quality ◽

Olive Mill Wastewater ◽

Short Term ◽

Olive Oil Quality ◽

Olive Mill ◽

Short Term Effects

Download Full-text

Ultra-Pure Hydrogen via Co-Valorization of Olive Mill Wastewater and Bioethanol in Pd-Membrane Reactors

Processes ◽

10.3390/pr8020219 ◽

2020 ◽

Vol 8 (2) ◽

pp. 219 ◽

Cited By ~ 4

Author(s):

David Alique ◽

Giacomo Bruni ◽

Raúl Sanz ◽

José Antonio Calles ◽

Silvano Tosti

Keyword(s):

Hydrogen Production ◽

Space Velocity ◽

Green Energy ◽

Olive Mill Wastewater ◽

Membrane Reactors ◽

Pure Hydrogen ◽

Permeate Flux ◽

Pd Membrane ◽

H2 Recovery ◽

Olive Mill

Olive mill wastewater (OMW) presents high environmental impact due to the fact of its elevated organic load and toxicity, especially in Mediterranean countries. Its valorization for simultaneous pollutants degradation and green energy production is receiving great attention, mainly via steam reforming for hydrogen generation. Following previous works, the present research goes into detail about OMW valorization, particularly investigating for the first time the potential benefits of OMW–bioethanol mixtures co-reforming for ultra-pure hydrogen production in Pd-membrane reactors. In this manner, the typical large dilution of OMW and, hence, excess water can be used as a reactant for obtaining additional hydrogen from ethanol. Fresh OMW was previously conditioned by filtration and distillation processes, analyzing later the effect of pressure (1–5 bar), oxidizing conditions (N2 or air as carrier gas), gas hourly space velocity (150–1500 h−1), and alcohol concentration on the co-reforming process (5–10% v/v). In all cases, the exploitation of OMW as a source of environmentally friendly hydrogen was demonstrated, obtaining up to 30 NmL·min−1 of pure H2 at the most favorable experimental conditions. In the membrane reactor, higher pressures up to 5 bar promoted both total H2 production and pure H2 recovery due to the increase in the permeate flux despite the negative effect on reforming thermodynamics. The increase of ethanol concentration also provoked a positive effect, although not in a proportional relation. Thus, a greater effect was obtained for the increase from 5% to 7.5% v/v in comparison to the additional improvement up to 10% v/v. On the contrary, the use of oxidative conditions slightly decreased the hydrogen production rate, while the effect of gas hourly space velocity needs to be carefully analyzed due to the contrary effect on potential total H2 generation and pure H2 recovery.

Download Full-text