scholarly journals Hydrogen gas production and pollutant removal from olive mill wastewater by electrohydrolysis

Author(s):  
S. Erdem ◽  
H. Bag ◽  
C. Can Yarimtepe ◽  
O. Ince ◽  
N. Ayman Oz
Author(s):  
Reda Elkacmi ◽  
Noureddine Kamil ◽  
Mounir Bennajah

Treatment of olive mill wastewater (OMW) by electrocoagulation (EC) was investigated in a stirred tank reactor (STR), the effect of different influential parameters, namely, contact time, current density and pH was determined. Over 72 % of COD, 93 % of polyphenols and 95 % of color intensity were removed efficiently at pH of 5.2, current density of 58.33 mA/cm2 and a residence time of 45 min. A kinetic study of these three parameters was carried out and both COD and dark color removal obey the first-order law model. On the other hand, the polyphenols reduction, fits the pseudo second-order model with current- dependent parameters. A variable order kinetic (VOK) model derived from the Langmuir-Freundlish equation was proposed to determine the kinetics of pollutant removal reactions with EC. Results showed that the model equations strongly fit the experimental concentrations of the three pollutants.


2015 ◽  
Vol 40 (12) ◽  
pp. 4303-4310 ◽  
Author(s):  
Andrea Speltini ◽  
Michela Sturini ◽  
Federica Maraschi ◽  
Daniele Dondi ◽  
Gabriele Fisogni ◽  
...  

2015 ◽  
Vol 69 (5) ◽  
pp. 577-583 ◽  
Author(s):  
Michail Michailides ◽  
Triantafillos Tatoulis ◽  
Mar-Yam Sultana ◽  
Athanasia Tekerlekopoulou ◽  
Ioannis Konstantinou ◽  
...  

An olive mill's existing evaporation pond was separated into five cells and transformed into a free water surface constructed wetland. The constructed wetland was used as a post-treatment stage for olive mill wastewater (OMW). Wastewater was previously treated by an aerobic trickling filter. The influent concentrations in the constructed wetland were 27400 mg.L-1, 4800 mg.L-1, 105 mg.L-1 and 770 mg.L-1 for COD, phenols, ortho-phosphate and TKN, respectively. Despite the rather high influent concentrations, the performance of the constructed wetland was very good since after the 60-day start-up operation period it achieved removal rates of about 94%, 95%, 95% and 98% for COD, phenols, ortho-phosphate and TKN, respectively. The major pollutant removal processes can be attributed to both biological processes occurring in the wetland and photo-oxidation. Laboratory-scale experiments with OMW from fifth cell of the wetland revealed that the net contribution of photo-oxidation after 112 hours of simulated solar radiation at 765 W/m2 (i.e. about 38 days of sunlight irradiation) was 18% and 31% removal for COD and phenols, respectively. In the constructed wetland, the total removal reached 81% and 86% for COD and phenols, respectively, for the same time period (38 days).


2021 ◽  
Vol 13 (4) ◽  
pp. 2376
Author(s):  
Dimitris P. Zagklis ◽  
Costas S. Papageorgiou ◽  
Christakis A. Paraskeva

Olive mill wastewater is an important agro-industrial waste with no established treatment method. The authors have developed a phenol separation method that could potentially cover the treatment cost of the waste. The purpose of this study was to identify any economic hotspots in the process, the operational cost and examine the margin of profit for such a process. The equipment cost was scaled for different treatment capacities and then used to estimate the fixed capital investment and the yearly operational cost. The highest purchased equipment cost was identified for the membrane filtration system, while the cost for resin replacement was identified as the highest operational cost. The lifespan of the resin used in the adsorption step was identified as an economic hot spot for the process, with the phenols separation cost ranging from 0.84 to 13.6 €/g of phenols for a resin lifespan of 5–100 adsorption/desorption cycles. The lifespan of the resin proved to be the single most important aspect that determines the phenols separation cost. The price range that was calculated for the product of the process is very promising because of the typical value of antioxidants and the low concentration of phenols that are needed for food supplements and cosmetics.


2021 ◽  
Vol 42 ◽  
pp. 100402
Author(s):  
Jacques Romain Njimou ◽  
John Godwin ◽  
Hugues Pahimi ◽  
S. Andrada Maicaneanu ◽  
Fridolin Kouatchie-Njeutcha ◽  
...  

Foods ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 800
Author(s):  
Anna Maria Posadino ◽  
Annalisa Cossu ◽  
Roberta Giordo ◽  
Amalia Piscopo ◽  
Wael M Abdel-Rahman ◽  
...  

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.


Sign in / Sign up

Export Citation Format

Share Document