Olive Mill Wastewater: From a Pollutant to Green Fuels, Agricultural Water Source, and Bio-Fertilizer. Part 2: Water Recovery

Water shortage is a very concerning issue in the Mediterranean region, menacing the viability of the agriculture sector and in some countries, population wellbeing. At the same time, liquid effluent volumes generated from agro-food industries in general and olive oil industry in particular, are quite huge. Thus, the main aim of this work is to suggest a sustainable solution for the management of olive mill wastewaters (OMWW) with possible reuse in irrigation. This work is a part of a series of papers valorizing all the outputs of a three-phase system of oil mills. It deals with recovery, by condensation, of water from both OMWW and OMWW-impregnated biomasses (sawdust and wood chips), during a convective drying operation (air velocity: 1 m/s and air temperature: 50 °C). The experimental results showed that the water yield recovery reaches about 95%. The condensate waters have low electrical conductivity and salinities but also acidic pH values and slightly high chemical oxygen demand (COD) values. However, they could be returned suitable for reuse in agriculture after additional low-cost treatment.

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Experimental and statistical evaluation of the performance of Chitosan as a coagulant in the treatment of sugar refinery effluents

10.51415/10321/1372 ◽

2015 ◽

Author(s):

◽

Ritha-Lorette Luti Pambi

Keyword(s):

New Technologies ◽

Sugar Industry ◽

Low Cost ◽

Oxygen Demand ◽

Good Method ◽

Settling Time ◽

Simultaneous Increase ◽

Water Recovery ◽

Dissolved Solids ◽

Sugar Refinery

The implementation of new water regulations from the local government has been a motivation for most industries to treat the effluent before disposal or reuse within the plant, in order to save costs and avoid sanctions. Tongaat-Huletts sugar refinery has therefore invested in this collaborative research with the Durban University of Technology in order to investigate new technologies for wastewater treatment and water recovery using an organic coagulant called chitosan. Chitosan is a natural non-toxic polymer extracted from the exoskeleton of crustaceans. Chitosan has gained extensive attention as a coagulant in the treatment of wastewaters from various industries. However, no attention has been given to the coagulation of effluents from the sugar industry using this polymer. In this work, chitosan coagulant (CCo) was prepared by dissolution of known amounts of chitosan powder in aqueous acid at 50℃. The solution was diluted to desired concentrations using distilled water at room temperature. The removal of impurities using chitosan was investigated for two effluent streams from the sugar refinery, namely the final effluent (FE) and the resin effluent (RE) by applying the one-factor-at-a-time (OFAT) method. The optimum chitosan loading was found to be 138 mg/l for the RE and 7.41 mg/l for the FE, beyond which the efficiency of the coagulant decreased. The coagulation of FE removed 97% of the total suspended solids (TSS), 61% colour and 35% chemical oxygen demand (COD). The treatment of RE resulted in the removal of 68% TSS, 30% colour and 15% COD due to its high content of impurities. Therefore, RE was not considered for statistical studies. The Box-Behnken (BBD) design, which is a statistical response surface methodology (RSM) model was used to study the simultaneous effect of pH, coagulant loading and settling time on the removal of the COD, TSS and colour, with the help of an overlay plot for the FE. The optimum values from the overlay plot were 92% for TSS, 83% for colour and 29% for COD. The model equations generated by the BBD for individual responses involved all the manipulated variables contrary to the OFAT which only considered one manipulated parameter per response. Moreover, the BBD allowed the simultaneous analysis of all the parameters and the identification of interactions which occur when the effect of one factor is dependent on the level of another. The most important interaction for the removal of TSS was the combination of the variation in pH and coagulant dosage. The COD removal was mostly affected by the interaction between the coagulant loading and the settling time. The colour removal increased with the simultaneous increase of the pH and the settling time. A comparative study between the wastewaters from the sugar industry, the brewery industry and milk processing industry revealed that the performance of the chitosan was also affected by the amount of total dissolved solids (TDS) in the wastewater. A model was developed relating the TSS, COD and TDS from all these wastewaters, and was used to predict the TSS removal for the effluent from the olive oil mills and the wastewater from the winery. Chitosan can be considered as a good alternative to inorganic and synthetic coagulants for the pre-treatment of the FE due to its ability to efficiently remove the levels of TSS and colour. Furthermore, the production of chitosan from crustacean shells is a good method of reducing pollution from the fishery industry. Chitosan can be produced locally at low cost due to both the abundance of crustacean shells in the coastal regions of South Africa and the simplicity of its preparation process. It is recommended that a mathematical model be developed to accurately predict the influence of chitosan on all types of effluent. Such a model will provide an indication of the performance of the chitosan and guide experimenters. It is further recommended that the effect of the use of organic coagulants on the destabilization of dissolved solids in wastewater be given greater attention.

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The color removal and fate of organic pollutants in a pilot-scale MBR-NF combined process treating textile wastewater with high water recovery

Water Science & Technology ◽

10.2166/wst.2015.623 ◽

2015 ◽

Vol 73 (6) ◽

pp. 1426-1433 ◽

Cited By ~ 4

Author(s):

Kun Li ◽

Chao Jiang ◽

Jianxing Wang ◽

Yuansong Wei

Keyword(s):

Membrane Fouling ◽

Oxygen Demand ◽

Textile Wastewater ◽

High Water ◽

Pilot Scale ◽

Water Yield ◽

Water Recovery ◽

Treatment Efficiency ◽

Textile Mill ◽

Refractory Compounds

A combination of membrane bioreactor (MBR) and nanofiltration (NF) was tested at pilot-scale treating textile wastewater from the wastewater treatment station of a textile mill in Wuqing District of Tianjin (China). The MBR-NF process showed a much better treatment efficiency on the removal of the chemical oxygen demand, total organic carbon, color and turbidity in comparison with the conventional processes. The water recovery rate was enhanced to over 90% through the recycling of NF concentrate to the MBR, while the MBR-NF showed a stable permeate water quality that met with standards and could be directly discharged or further reused. The recycled NF concentrate caused an accumulation of refractory compounds in the MBR, which significantly influenced the treatment efficiency of the MBR. However, the sludge characteristics showed that the activated sludge activity was not obviously inhibited. The results of fluorescence spectra and molecular weight distribution indicated that those recalcitrant pollutants were mostly protein-like substances and a small amount of humic acid-like substances (650–6,000 Da), which contributed to membrane fouling of NF. Although the penetrated protein-like substances caused the residual color in NF permeate, the MBR-NF process was suitable for the advanced treatment and reclamation of textile wastewater under high water yield.

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Eco-friendly approach for elimination of olive mill wastewaters (OMW) toxicity using cactus prickly pears juice as a coagulant

Water Practice & Technology ◽

10.2166/wpt.2020.076 ◽

2020 ◽

Vol 15 (4) ◽

pp. 1050-1067

Author(s):

M. Neffa ◽

M. Taourirte ◽

N. Ouazzani ◽

H. Hanine

Keyword(s):

Low Cost ◽

Mixing Time ◽

Oxygen Demand ◽

Physicochemical Analysis ◽

Jar Test ◽

Coagulation Mechanism ◽

Olive Mill Wastewaters ◽

Series Of Experiments ◽

Prickly Pears ◽

Olive Mill

Abstract Currently, research focuses on the application of newer biocoagulant products in wastewater treatment. In this study, the performance of cactus juice to clarify Olive Mill Wastewater (OMW) was investigated by using Jar-test experimentation and assessed by physicochemical analysis of the obtained supernatant: turbidity, total suspended solids (TSS), (λ465; λ395) absorbance, polyphenols (pp), chemical oxygen demand (COD) and Fourier-Transform-Infrared spectroscopy (FTIR) on lyophilized sludge. A series of experiments were conducted to estimate the influence of various experimental parameters, such as the amounts of biocoagulants used, time, stirring speed, and pH. The study showed the optimal coagulation conditions were as follows: sample pH10; cactus juice dose, 10% (v/v); rapid mixing time, 30 s at a speed of 150 rp/min. Under these conditions, the overall removals of 74% for COD, 93% for turbidity and 51% for polyphenols were achieved. As referring to the FTIR analysis, the cactus juice of Opuntia spp. operates predominantly through an adsorption interparticle bridging coagulation mechanism. These results are encouraging in the context of developing a low-cost technology and eco-friendly approach for the effective management of OMW.

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Water reuse as a secure pathway to deal with water scarcity

MATEC Web of Conferences ◽

10.1051/matecconf/202030500090 ◽

2020 ◽

Vol 305 ◽

pp. 00090 ◽

Cited By ~ 2

Author(s):

Vincenzo Torretta ◽

Ioannis Katsoyiannis ◽

Maria Cristina Collivignarelli ◽

Giorgio Bertanza ◽

Maria Xanthopoulou

Keyword(s):

Water Supply ◽

Water Reuse ◽

Oxygen Demand ◽

Water Shortage ◽

Treated Wastewater ◽

Future Climate Change ◽

Water Supply Systems ◽

Irrigation Canal ◽

Water Recovery ◽

Regulatory Approach

An adequate access to water supply systems is crucial for a sustainable future. Climate change is expected to increase water shortage problems worldwide. Reuse/recycling of treated wastewater for domestic and/or agricultural purposes can be considered an interesting water supply: it is independent from seasonal drought and meteorological variability and able to cover the peak of water demand. In the case of direct reuse, the parameter of treated water must comply with the reuse limits for biological oxygen demand, chemical oxygen demand and suspended solids. In case of indirect reuse, the regulatory approach changes as the dilution ratio between discharge and flow of the irrigation canal is taken into account too. There are many interventions that are considered useful for the purpose of promoting the development of an enhanced water recovery and recycling: legislation improvements, modification in the water storage management, prevention in pollution discharged into sewerage systems, improving the efficiency of WWTPs, incentive the adoption of rainwater storage tanks and interventions for the separation of gray water, establish a “blue certificate” for financing investments. In the present paper those aspects are analysed referring to some cases found in an Italian region.

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Extraction of Polycyclic Aromatic Hydrocarbons and Polychlorinated Biphenyls from Urban and Olive Mill Wastewaters Intended for Reuse in Agricultural Irrigation

Journal of AOAC International ◽

10.5740/jaoacint.19-0257 ◽

2020 ◽

Vol 103 (2) ◽

pp. 382-391

Author(s):

Maria Concetta Bruzzoniti ◽

Luca Rivoira ◽

Michele Castiglioni ◽

Ayoub El Ghadraoui ◽

Abdelaali Ahmali ◽

...

Keyword(s):

Polycyclic Aromatic Hydrocarbons ◽

Polychlorinated Biphenyls ◽

Aromatic Hydrocarbons ◽

Solid Phase ◽

Wastewater Reuse ◽

Oxygen Demand ◽

Water Source ◽

Polycyclic Aromatic ◽

Analytical Procedures ◽

Olive Mill

Abstract Background: Domestic and industrial wastewater can be introduced in a reuse chain for irrigation purposes. Objective: In this paper, we developed analytical procedures for the extraction of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) along a wastewater reuse chain for irrigation purposes. Besides urban wastewaters, olive mill wastewater (OMWW) was considered as a potential water source. Wastewaters were purified by different treatments (urban wastewater plants, pilot-activated sludge, and constructed wetland) and used for the irrigation of olive trees. Suitable extraction procedures were used to analyze treated and untreated wastewaters, soils, and postirrigation leachates. Results: For wastewater and leachate samples, the optimized reverse-phase solid-phase extraction (SPE) provided recoveries up to 79%. For OMWW, the SPE procedure was preceded by a normal-phase purification stage with silica gel for the removal of polyphenols, which were as high as 8.7 g/L. After optimization, extraction recoveries in blank solutions were in the range 20–67% and moderately reduced (10–38%) in OMWW as a result of the matrix effect (ME; –10/–60%) ascribed to the very high value of chemical oxygen demand (264 g/L). LODs of the method were below 1.1 µg/L (PAHs) and 3.2 µg/L (PCBs) using GC-MS analysis. For soil samples of different compositions, microwave-assisted extraction (MAE) provided better extraction recoveries and reproducibility than the more common quick, easy, cheap, effective, rugged, and safe approach, which was affected by a high ME. The LODs of the MAE/GC-MS method were below 4.9 µg/kg (PAHs) and 12.3 µg/kg (PCBs). Conclusions: The analytical procedures developed are a valuable tool to quantify the possible propagation of residual contamination from PAHs/PCBs with irrigation along the wastewater reuse chain.

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Advanced Treatment of Coking Wastewater by Oxidation Process Using Pyrite and Hydrogen Peroxide

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.726-731.2521 ◽

2013 ◽

Vol 726-731 ◽

pp. 2521-2525

Author(s):

Zhi Yong Zhang ◽

De Li Wu

Keyword(s):

Hydrogen Peroxide ◽

Oxidation Process ◽

Low Cost ◽

Oxygen Demand ◽

Utilization Efficiency ◽

Advanced Treatment ◽

Coking Wastewater ◽

Second Stage ◽

Potential Alternative ◽

High Utilization

Coking wastewater is a kind of recalcitrant wastewater including complicate compositions. Advanced treatment of coking wastewater by Fenton-Like reaction using pyrite as catalyst was investigated in this paper. The results show that the chemical oxygen demand (COD) of coking wastewater decreased significantly by method of coagulation combined with two-stage oxidation reaction. COD of wastewater can decrease from 250mg/l to 45mg/l after treatment, when 2g/L pyrite was used in each stage oxidation and the dosage of hydrogen peroxide (H2O2) is 0.2ml/l for first stage treatment, 0.1ml/l for second stage treatment respectively. The pyrite is effective to promote Fenton-Like reaction with low cost due to high utilization efficiency of H2O2, moreover, catalyst could be easily recovered and reused. The Fenton-Like reaction might be used as a potential alternative to advanced treatment of recalcitrant wastewater.

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Burkholderia thailandensis E264 as a promising safe rhamnolipids’ producer towards a sustainable valorization of grape marcs and olive mill pomace

Applied Microbiology and Biotechnology ◽

10.1007/s00253-021-11292-0 ◽

2021 ◽

Author(s):

Alif Chebbi ◽

Massimiliano Tazzari ◽

Cristiana Rizzi ◽

Franco Hernan Gomez Tovar ◽

Sara Villa ◽

...

Keyword(s):

Energy Source ◽

Olive Oil ◽

Low Cost ◽

Carbon Sources ◽

Burkholderia Thailandensis ◽

Rhamnolipid Production ◽

Key Points ◽

Wide Range ◽

Long Chain ◽

Olive Mill

Abstract Within the circular economy framework, our study aims to assess the rhamnolipid production from winery and olive oil residues as low-cost carbon sources by nonpathogenic strains. After evaluating various agricultural residues from those two sectors, Burkholderia thailandensis E264 was found to use the raw soluble fraction of nonfermented (white) grape marcs (NF), as the sole carbon and energy source, and simultaneously, reducing the surface tension to around 35 mN/m. Interestingly, this strain showed a rhamnolipid production up to 1070 mg/L (13.37 mg/g of NF), with a higher purity, on those grape marcs, predominately Rha-Rha C14-C14, in MSM medium. On olive oil residues, the rhamnolipid yield of using olive mill pomace (OMP) at 2% (w/v) was around 300 mg/L (15 mg/g of OMP) with a similar CMC of 500 mg/L. To the best of our knowledge, our study indicated for the first time that a nonpathogenic bacterium is able to produce long-chain rhamnolipids in MSM medium supplemented with winery residues, as sole carbon and energy source. Key points • Winery and olive oil residues are used for producing long-chain rhamnolipids (RLs). • Both higher RL yields and purity were obtained on nonfermented grape marcs as substrates. • Long-chain RLs revealed stabilities over a wide range of pH, temperatures, and salinities

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Effects of Climate and Land Use/Land Cover Changes on Water Yield Services in the Dongjiang Lake Basin

ISPRS International Journal of Geo-Information ◽

10.3390/ijgi10070466 ◽

2021 ◽

Vol 10 (7) ◽

pp. 466

Author(s):

Wenbo Mo ◽

Yunlin Zhao ◽

Nan Yang ◽

Zhenggang Xu ◽

Weiping Zhao ◽

...

Keyword(s):

Land Use ◽

Land Cover ◽

Water Resource Management ◽

Water Source ◽

Water Yield ◽

Lake Basin ◽

Lake Area ◽

Land Use Land Cover ◽

Lulc Changes ◽

Regional Water

Spatial and quantitative assessments of water yield services in watershed ecosystems are necessary for water resource management and improved water ecological protection. In this study, we used the InVEST model to estimate regional water yield in the Dongjiang Lake Basin in China. Moreover, we designed six scenarios to explore the impacts of climate and land use/land cover (LULC) changes on regional water yield and quantitatively determined the dominant mechanisms of water yield services. The results are expected to provide an important theoretical reference for future spatial planning and improvements of ecological service functions at the water source site. We found that (1) under the time series analysis, the water yield changes of the Dongjiang Lake Basin showed an initial decrease followed by an increase. Spatially, water yield also decreased from the lake area to the surrounding region. (2) Climate change exerted a more significant impact on water yield changes, contributing more than 98.26% to the water yield variability in the basin. In contrast, LULC had a much smaller influence, contributing only 1.74 %. (3) The spatial distribution pattern of water yield services in the watershed was more vulnerable to LULC changes. In particular, the expansion of built-up land is expected to increase the depth of regional water yield and alter its distribution, but it also increases the risk of waterlogging. Therefore, future development in the basin must consider the protection of ecological spaces and maintain the stability of the regional water yield function.

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A Cyanobacteria-Based Biofilm System for Advanced Brewery Wastewater Treatment

Applied Sciences ◽

10.3390/app11010174 ◽

2020 ◽

Vol 11 (1) ◽

pp. 174

Author(s):

Konstantinos P. Papadopoulos ◽

Christina N. Economou ◽

Athanasia G. Tekerlekopoulou ◽

Dimitris V. Vayenas

Keyword(s):

Wastewater Treatment ◽

Biomass Production ◽

Low Cost ◽

Oxygen Demand ◽

Dry Weight ◽

Surface Hydrophobicity ◽

Reactor Performance ◽

Brewery Wastewater ◽

Kjeldahl Nitrogen ◽

Supporting Materials

Algal/cyanobacterial biofilm photobioreactors provide an alternative technology to conventional photosynthetic systems for wastewater treatment based on high biomass production and easy biomass harvesting at low cost. This study introduces a novel cyanobacteria-based biofilm photobioreactor and assesses its performance in post-treatment of brewery wastewater and biomass production. Two different supporting materials (glass/polyurethane) were tested to investigate the effect of surface hydrophobicity on biomass attachment and overall reactor performance. The reactor exhibited high removal efficiency (over 65%) of the wastewater’s pollutants (chemical oxygen demand, nitrate, nitrite, ammonium, orthophosphate, and total Kjeldahl nitrogen), while biomass per reactor surface reached 13.1 and 12.8 g·m−2 corresponding to 406 and 392 mg·L−1 for glass and polyurethane, respectively, after 15 days of cultivation. The hydrophilic glass surface favored initial biomass adhesion, although eventually both materials yielded complete biomass attachment, highlighting that cell-to-cell interactions are the dominant adhesion mechanism in mature biofilms. It was also found that the biofilm accumulated up to 61% of its dry weight in carbohydrates at the end of cultivation, thus making the produced biomass a suitable feedstock for bioethanol production.

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