Vegetable Oil Refinery Wastewater Research Articles

Optimization of coagulation-flocculation process for wastewater treatment from vegetable oil refineries using chitosan as a natural flocculant

Vegetable oil refinery wastewater (VORW) is a significant source of refractory pollutants necessitating efficient treatment prior to discharge. This study investigates the treatment of VORW via coagulation-flocculation using ferric chloride (FeCl3) as a coagulant and chitosan as a natural flocculant. Central Composite Design (CCD) is employed to optimize the treatment process and assess the interplay of experimental factors. The study evaluates turbidity, COD, and polyphenols as responses, with pH, FeCl3 concentration, chitosan dosage, and agitation time as independent factors.The results showed that the optimal conditions identified include pH 6, FeCl3 dosage of 1.6 g/L, chitosan dosage of 13.4 mg/L, and agitation time of 26 min, resulting in 100 % turbidity removal, 86 % COD reduction, and 90 % polyphenol removal. The analysis of variance indicated that the established models were significant and that they are characterized by a good fit (R2 in the order of 0.95, 0.96, and 0.96 for turbidity, COD, and polyphenols, respectively).These findings highlight the efficacy and sustainability of the coagulation-flocculation process with chitosan, offering a practical, rapid, and cost-effective solution for VORW treatment and environmental preservation.

Combined natural flotation and chemical precipitation for the treatment of vegetable oil refinery wastewater

Combined natural flotation and chemical precipitation for the treatment of vegetable oil refinery wastewater

Phytotoxicity assessment of treated vegetable oily wastewater via environmentally coagulation/flocculation and membrane filtration technologies using lettuce (Lactuca sativa) seeds.

The present investigation highlights the necessity of monitoring some basic physico-chemical water quality indicators and their phytotoxic effect using ecotoxicological bioassays such as "seed germination tests." The phytotoxicity of raw and treated vegetable oil refinery wastewater (VORW) using different treatment processes was assessed through some physiological responses (relative seed germination (RSG), seedling elongation, and germination index (GI)) using Lactuca sativa cultivar. Biotest results of different raw water samples revealed a noticeable correlation between the organic matter content and water phytotoxicity. In fact, VORW showed a very low RSG (17 ± 0.7 to -47 ± 0.58%) and high phytotoxic effects (GI < 50%). The use of coagulation/flocculation (CF) allowed a satisfactory phytotoxicity removal where RSG obtained ranged from 83 ± 1.58 to 90 ± 1.2%. However, the effluent still presents high to moderate phytotoxicity since GI remained below 80% which indicates the presence of toxic elements remaining after CF treatment. When VORW were treated using membrane processes, their phytotoxicity was gradually decreased with the decrease in the membrane pore size. The use of microfiltration membranes (MF), with pore size of 5 µm, 1.2 µm, 0.45 µm, and 0.22 µm, showed RSG values ranged from 37 ± 1.15 to 77 ± 1.68% and GI of less than 80% indicating a moderate to high phytotoxicity. However, the use of ultrafiltration (UF) membranes with molecular weight cut-off (MWCO) of 100 kDa, 30 kDa, and 10 kDa made it possible to achieve an RSG of 100% and an IG exceeding 80% showing that the VORW-treated using UF does not exhibit any phytotoxicity effect. Hence, UF appears to be the most efficient and environmentally friendly technology that could be used for safely treated VORW irrigation purposes compared to CF and MF processes.

Treatment of vegetable oil refinery wastewater by sequential electrocoagulation-electrooxidation process

In the present study a sequential process composed of electrocoagulation (EC) followed by electrooxidation (EO) was utilized at the laboratory scale to remove the chemical oxygen demand (COD) from wastewater generated in Iraqi vegetable oil refinery plant.in the EC, impacts of operating variables such as current density (10–30 mA cm-2) and pH (4–10),and EC time (30–90 min) on the COD removal (RE%) were investigated using response surface methodology (RSM) based on Box- Behnken design(BBD). a mathematical correlation that relates the operating factors with RE% was developed and its regression coefficient was 99.02% confirming the significant of the model. Response surface plots showed that RE% increased with increasing current density and time while it decreased with increasing pH. The optimum removal with a lower cost for EC process were achieved at current density of 30mA/cm2, pH of 4, and electrolysis time of 90 min in which RE% of 69.19% was obtained with requirement of 0.513kWh/kg COD as specific energy consumption (SEC). The effluent exit from EC was treated by EO for a period of 240min at a current density of 30mA/cm2 and an initial pH value of 4 to obtain RE% of 96% at SEC of 1.554 kWh/kg COD. Combining EC with EO resulted in a total RE% of 98.72% and a total SEC of 2.067 kWh/kg COD. Based on the results of present study, the applicability of a sequential electrocoagulation-electrooxidation process for treatment vegetable oil wastewaters is feasible.

Vegetable Oil Refinery Wastewater Treatment by Using the Cactus as a Bio-flocculant in the Coagulation-Flocculation Process

Vegetable Oil Refinery Wastewater Treatment by Using the Cactus as a Bio-flocculant in the Coagulation-Flocculation Process

Optimization of the coagulation-flocculation process for vegetable oil refinery wastewater using a full factorial design

Vegetable oil refineries wastewater poses significant challenges to treatment techniques due to its characteristic fluctuations. In this study, a full factorial design (FFD) was applied to investigate the effect of the experimental variable (pH, coagulant dose, flocculant dose, and pollutant load) for the turbidity (Y1) and COD (Y2) removal by the coagulation-flocculation process. The results showed that the linear regression models were well suited to the experimental data, with correlation coefficients R2adj of 0.96 and 0.9 for Y1 and Y2, respectively. According to the ANOVA analysis, linear effects were detected significantly for the four factors examined on turbidity and COD removal. This study has shown that coagulation-flocculation is effective for turbidity removal, regardless of the pollutant load of wastewater. Under optimal conditions using 1 g L−1 FeCl3 and 1 mL L−1 cationic polymer at a pH = 8, the turbidity removal reaches 82% and 97.5% for a low and high pollution load, respectively. In contrast, the COD removal reaches 79.5% and 58% for low and high pollution loads, respectively. These results prove that the efficiency of physicochemical treatment in organic matter removal is more effective in less polluting industrial wastewater. This strongly suggests that a physical pretreatment is a promising option for the best efficiency of coagulation-flocculation.

Valorization of Opuntia ficus-Indica Pads and Steel Industry FeCl 3 -Rich Rejection for Removing Surfactant and Phenol from Oil Refinery Wastewater Through Coagulation-Flocculation

Background.Refinement of crude vegetable oil generates a large amount of wastewater and is a source of water pollution due to the presence of surfactants and phenols. Phenols are toxic aromatic compounds that can be lethal to fauna and flora, entraining the deceleration or blocking of the self-purification of biological treatments. In addition, surfactants can limit biological processes by inhibiting microorganisms that degrade organic matter.Objectives. The aim of the present study was to evaluate the treatment of refinery rejects loaded with phenols and detergents by coagulation flocculation using cactus pads (genus Opuntia) as a bio-flocculant and 30% iron(III) chloride (FeCl3) for surfactant and phenol removal. In addition, operating costs were evaluated for these pollution mitigation methods.Methods.The effectiveness of cactus pads as a bio-flocculant and 30% FeCl3 for surfactant and phenol removal were studied using a jar test. The study was conducted on vegetable oil refinery wastewater from a refinery company in Casablanca, Morocco.Results.The pollution load in wastewater varied widely from day to day. We evaluated the effect of cactus juice and 30% FeCl3 on high and low pollution loads. Opuntia pads showed a favorable potential for the treatment of low pollution load wastewater, with 78% and 90% of surfactant and phenol removed, respectively. However, the removal of high pollution load was less effective (42% and 41% removal of surfactant and phenol, respectively). The turbidity of low and high pollution load was reduced by 98.85% and 86%, respectively. The results demonstrate that 30% FeCl3 can effectively treat both low and high pollution loads (90% and 89% phenol removal, respectively, and 90% and 70% surfactant removal, respectively (optimal concentration 1.48 g/l). The turbidity was reduced by over 96% for both high and low pollutants.Conclusions.The results of the present study indicate that cactus as a natural flocculant and reject rich in FeCl3 could be effectively used for the low-cost effective treatment of crude vegetable oil refinery rejects.Competing Interests.The authors declare no competing financial interests

Efficiency of a coagulation/flocculation–membrane filtration hybrid process for the treatment of vegetable oil refinery wastewater for safe reuse and recovery

Treatment of real (RVORW) and synthetic (SVORW) vegetable oil refinery wastewaters using membrane filtration system was experimentally studied. Experimental runs with SVORW were used to identify the best conditions to perform with RVORW treatment. The bench-scale experiment was carried out using a commercial ceramic 0.245m2 ultrafiltration (UF) membrane (150kDa) in cross-flow filtration (CFF) mode at a flow rate of 3000 L⋅h−1 and a trans-membrane pressure (TMP) of 1.2bars. However, such membrane is vulnerable to fouling and it is insufficient to give water of good quality suitable for reuse. This investigation, aims to improve the purification performances of UF by exploring its combination with other treatment options, i.e. optimized coagulation/flocculation (CF) as pre-treatment and dead-end filtration (DEF) as post-treatment for better treated-water quality. According to the results, when using CF as pre-treatment under optimal conditions (2.4 g⋅L-1of aluminium sulfate, 60.05 mg⋅L-1 of CHT flocculant, under initial pH of 9.23), the hybrid CF/UF process allows to achieve the best treated RVORW water quality with turbidity, COD and TOC removals reaching 100 %, 98 % and 97 % respectively compared to those of CF and UF used separately, with membrane permeability of 135 L⋅h−1⋅m-2⋅bar−1 which is in agreement with an industrial application.

Treatment of vegetable oil refinery wastewater with biodegradability index improvement

The vegetable oil refinery wastewater (VORWW) creates an environmental problem in terms of threat to aquatic life due to high organic and inorganic content. These refinery plants produce a large quantity of wastewater with high chemical oxygen demand (COD) and biological oxygen demand (BOD). In this research, HC was evolved as a recent treatment option for the treatment of VORWW. Various parameters like inlet pressure, pH, temperature and H2O2 dose were tested during experimentation to determine BOD, COD, and BI (BOD/COD ratio). Using the hydrodynamic cavitation (HC) reactor biodegradability index (BI) of 0.69 and COD reduction up to 71.8% were obtained. In this same condition BOD increases by 14.4%, which helps to increase BI at optimum conditions of 120 min reaction time, operating temperature 20 °C, inlet pressure 8 bar, pH-4 and H2O2 dose of 25 g/L. It was found that the operating pressure of 8 bar in the HC reactor gives the maximum BI (BOD/COD ratio). The obtained optimum conditions of HC were used in the Ultrasonic cavitation reactor for the degradation of VORWW. In the 80 min of treatment COD reduced by 73.2%, which is highest as compared to HC. Similarly, BOD increases by 12.7% in just 80 min of treatment. The final obtained BI is 0.71, COD of 5984 mg/L and BOD 4270 mg/L which seems good as compared to HC.

Biovalorization of vegetable oil refinery wastewater into value‐added compounds by Yarrowia lipolytica

AbstractBACKGROUNDVegetable oil refinery wastewater (VORW) is an environmental pollutant in less developed countries which annually produce 75% of vegetable oils worldwide. Microbial oils from low‐cost substrates are of growing importance for the production of renewable biofuel feedstocks, and food and feed supplements. In the current study, VORW was used as a cheap substrate to produce added‐value compounds including lipase, microbial oil and lipid‐rich biomass using Yarrowia lipolytica. The chemical oxygen demand (COD) reduction of the wastewater was studied after fermentation.RESULTSThe maximum microbial oil concentration and lipase activity were 2.68 g L−1 and 8 U mL−1 after 48 h of inoculation. The microbial oil production increased from 2.86 g L−1 to 7.74 g L−1 after optimization by response surface methodology. Using optimized medium, 11 g L−1 microbial oil and 18.3 g L−1 biomass were obtained in the bioreactor culture. The amount of unsaturated fatty acids (FAs) reached ≤63% in the resulting microbial oil with a suitable FA profile for the production of lipid‐rich biomass. The biomass of Y. lipolytica has 60% lipid content and a significant amount of essential FAs which makes it as a proper feed supplement. The COD level of the wastewater decreased by 80% after 20 h.CONCLUSIONVORW can be used as a promising substrate for the sustainable production of microbial oil and lipid‐rich biomass with useful FAs by Y. lipolytica. This process also can simultaneously reduce environmental pollution of wastewater in a safe and eco‐friendly way. © 2019 Society of Chemical Industry

Optimization of batch electrocoagulation process using Box-Behnken experimental design for the treatment of crude vegetable oil refinery wastewater

The performance of the batch electrocoagulation process for the treatment of real crude vegetable oil refinery wastewater with high COD using sacrificial aluminum anode was explored in this research. Effects of operating factors such as electrolysis time (0–60 min), applied voltage (10–20 V) and electrode spacing (2–4 cm) on the COD removal were investigated. Mathematical model relating these key operating factors and the COD removal was developed using Box-Behnken design. 3-D response surface plots showed that the COD removal significantly increased with increase in electrolysis time and applied voltage till the optimum value. COD removal decreased, when very short or excessive electrode spacing was fixed. Experimental COD removal of 70.8% was attained at the optimized conditions and observed to be in reasonable agreement with the prediction by the Box-Behnken design.

Deturbidization of Vegetable Oil Refinery Wastewater with Extracted Fish Scale Biomass via Coagulation Process; Non-linear Kinetics Studies

Chito-protein was successfully synthesized from fish scale. The ability of a coagulant (chito-protein) prepared from fish scale (FSC) to carry out an effective removal of pollutants from food processing industry (vegetable oil industry wastewater, VOW) was evaluated at bench scale using a simulated jar test analysis. The coagulant was characterized via proximate analysis and instrumental analysis: Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The maximum kinetic parameters determined were recorded at K of 2x10-5L/mg.min, 1g, t1∕2= 50 min, R2= 0.9245 and pH of 2.Regression coefficient analysis (R2) was used to ascertain the accuracy of the fit to the postulated kinetic model. However, it was concluded that the second order kinetic model described the reaction most adequately. Removal efficiency of turbidity (87.21%) was obtained at optimum contact time of 30 min, pH 2, coagulant dosage of 1.5g and temperature of 323K. Kinetic study showed that Pseudo first order and pseudo second order models were the best two models in describing the coag-adsorptive kinetics of the coagulant. Similarly, the predicted kinetic data were adjured statistically significant using F- test and T-test.

Process optimization via response surface methodology in the physico-chemical treatment of vegetable oil refinery wastewater.

The present paper investigates the efficiency of coagulation/flocculation process using aluminum sulfate as coagulant and CHT industrial flocculent as coagulant aid/flocculent in the treatment of vegetable oil refinery wastewater (VORW). The process optimization was conducted in two steps, jar test experiments for preliminary evaluation to identify the most influencing factors and response surface methodology using Box-Behnken design to investigate the effects of three major factors and their interactions. The variables involved were the coagulant concentration (X1), flocculent dosage (X2), and initial pH (X3) of water samples, while the responses were COD removal (Y1) and residual turbidity (Y2). The optimal conditions obtained by solving the quadratic regression models, as well as by analyzing the response surface contour plots, were as follows: 2.4g/L of coagulant (aluminum sulfate), 60.05mg/L of flocculent, and about 9.23 as initial pH. Under these conditions, the coagulation/flocculation treatment was able to achieve 99% of COD removal with total turbidity elimination (100% removal). Analysis of variance showed high variance coefficient (R2) values of 0.929 and 0.836 for COD and turbidity removals, respectively, thus ensuring a satisfactory adjustment of the second-order regression model with the experimental data. This statistical design methodology was demonstrated as an efficient and feasible approach for the optimization of coagulation/flocculation treatment.

Treatment of vegetable oil refinery wastewater by coagulation - flocculation process using the cactus as a bio - flo c culant

Treatment of vegetable oil refinery wastewater by coagulation - flocculation process using the cactus as a bio - flo c culant

Removal of oil and grease from vegetable oil refinery wastewaters by coagulation-flocculation process

Due to the various industrial uses of oil and grease, the water pollution by these materials becomes more increasingly a serious problem. It is then a great necessity to find an efficient method leading to the removal of the oil and grease from the polluted waters. Attempts are made in the present work to examine the effectiveness of the coagulation process by using ferric chloride as a coagulant for the treatment of vegetable oil refinery wastewater. Thus, the decrease or the removal of various wastewater characteristics such as the organic matter amount expressed as chemical oxygen demand (COD), the aqueous solution turbidity and the oil and grease, using ferric chloride during coagulation process were investigated. Also, the optimum conditions leading to efficient coagulation were achieved by varying the coagulant dosage and the pH of the aqueous solution and by using jar test experiments. The results revealed that in the range of pH investigated, the optimal operating pH was found to be equal to 5. Further, the highest values for the COD (removal of organic matter), the removal of turbidity, and the removal of the oil and grease, from the wastewater, were found to be, respectively, 96%, 92%, and 99%. Theses values were achieved by the addition of 700 mg/L FeCl 3 ·6H 2 O to the wastewater. Therefore, it can be concluded that the coagulation method that we developed in the present work, is useful for the pre-treatment process for vegetable oil refinery wastewater prior to biological treatment.

Treatment of vegetable oil refinery wastewater using alumina ceramic membrane: optimization using response surface methodology

New regulations in environment protection and increasing market demands for “green” companies are forcing the industry to consider finding new and sustainable methods of wastewater treatment. The valuable information regarding treatment of the wastewater from the edible oil industry is presented in this research. The obtained results confirm a promising application of the third generation membranes, comprised of ceramic material (aluminium oxide), in treatment of wastewater from the edible oil industry. Positive results regarding chemical oxygen demand reduction and turbidity removal were noticed. Permeate flux values were used for process optimization in order to achieve a cost-effective process. Response surface methodology was used for the experimental design. The effects of wastewater temperature, transmembrane pressure, and feed-flow rate on the microfiltration model fit were studied. The experiments showed that microfiltration of this type of wastewater is a convenient technique for a possible large scale industrial application as a secondary step in treating wastewater from the oilseed processing facilities.

Treatment of vegetable oil refinery wastewater by sorption of oil and grease onto regranulated cork – A study in batch and continuous mode

The feasibility of a novel sorption treatment using regranulated cork granules for oil and grease (O&G) removal from real vegetable oil refinery wastewaters (VORW) was investigated and compared to similar treatment of oil-in-water emulsions.O&G sorption from real VORW onto regranulated cork particles was studied at different pH and ionic strength conditions. Only wastewater acidification was able to effectively destabilize the O&G emulsion in the wastewater, enhancing the sorption process (efficiency over 80% at pH 2.0).A 3-factor, 3-level (33) Box–Behnken experimental design was used to examine the effect of pH, ionic strength and soap/oil ratio on O&G removal efficiency in oil-in-water emulsions. All effects were significant (p<0.05) when considered individually, but no significant interactions were observed. pH was found to have the strongest effect, supporting the initial observations in real VORW.The treatment of a simulated wastewater (60% soap/oil ratio, 0.2M NaCl and pH 2.0) was completed in batch and continuous mode. Freundlich and linear partitioning models were used to describe O&G sorption equilibria. Continuous treatment was successfully carried out in a stirred-tank reactor using a cork dosage of 3.4gL−1, a stirring speed of 250rpm and a flowrate of 10mLmin−1. The reactor was fed for 8h with simulated wastewater (205±30mgL−1 O&G) yielding an effluent with an O&G content below 15mgL−1 (discharge limit defined in Portuguese legislation). A mass transfer model was applied to describe the O&G sorption kinetics in batch and continuous stirred-tank reactors.

Quality Assessment of Vegetable Oil Industry Effluents in Port Harcourt, Rivers State, Nigeria

Five composite samples of waste water were collected from waste water tank of a vegetable oil refining company and were analyzed for physiochemical characteristics, heavy metal and organic pollutants. Physicochemical determinations were done according to standard methods; heavy metals were determined by use of Atomic Absorption Spectrophotometer method while organic pollutants were determined by Gas chromatography system HP 6890 series. Sulphate was determined by vanadomolybdophosphoric acid method while phosphates and chlorides were determined by argentometric method. Results reveal that effluent pH (4.67 ±0.015), salinity (125 ±4.50 %) and BOD5 (17.83 ±1.70 mg/l) were bellow WHO standard whereas TDS (127.7 ±5.77 mg/l), TSS (563.6 ±3.15 mg/l) and COD (3959 ±3.8 mg/l) were above WHO standards. Heavy metal pollution index (0.31) showed no multi-element contamination arising from effluent. The degree of contamination (1.84) showed that the effluent has a moderate polluting potential. Lower molecular weight PAHs showed a significant difference even though most of the organic compounds in vegetable oil refinery wastewater showed good biodegradability that varied weekly. Therefore there is either no treatment or an in effective treatment of the effluents. This could result to serious environmental problems in the near future.

Quality Assessment of Vegetable Oil Industry Effluents in Port Harcourt, Rivers State, Nigeria

Five composite samples of waste water were collected from waste water tank of a vegetable oil refining company and were analyzed for physiochemical characteristics, heavy metal and organic pollutants. Physicochemical determinations were done according to standard methods; heavy metals were determined by use of Atomic Absorption Spectrophotometer method while organic pollutants were determined by Gas chromatography system HP 6890 series. Sulphate was determined by vanadomolybdophosphoric acid method while phosphates and chlorides were determined by argentometric method. Results reveal that effluent pH (4.67 ±0.015), salinity (125 ±4.50 %) and BOD5 (17.83 ±1.70 mg/l) were bellow WHO standard whereas TDS (127.7 ±5.77 mg/l), TSS (563.6 ±3.15 mg/l) and COD (3959 ±3.8 mg/l) were above WHO standards. Heavy metal pollution index (0.31) showed no multi-element contamination arising from effluent. The degree of contamination (1.84) showed that the effluent has a moderate polluting potential. Lower molecular weight PAHs showed a significant difference even though most of the organic compounds in vegetable oil refinery wastewater showed good biodegradability that varied weekly. Therefore there is either no treatment or an in effective treatment of the effluents. This could result to serious environmental problems in the near future.

Electrocoagulation of vegetable oil refinery wastewater using aluminum electrodes

Electrocoagulation with aluminum electrodes was used to treat the vegetable oil refinery wastewater (VORW) in a batch reactor. The effects of operating parameters such as pH, current density, PAC (poly aluminum chloride) dosage and Na 2SO 4 dosage on the removal of organics and COD removal efficiency have been investigated. It has been shown that the removal efficiency of COD increased with the increasing applied current density and increasing PAC and Na 2SO 4 dosage and the most effective removal capacity was achieved at the pH 7. The results indicate that electrocoagulation is very efficient and able to achieve 98.9% COD removal in 90 min at 35 mA cm −2 with a specific electrical energy consumption of 42 kWh (kg COD removed) −1. The effluent was very clear and its quality exceeded the direct discharge standard.