No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
Removal of COD from oil recovery industry wastewater by the advanced oxidation processes (AOP) based on H2O2
Abstract
The combinations of H2O2/Fe+2, UV/H 2O2/Fe+2 and UV/H2O2 process were investigated on treatment of oil recovery industry wastewater. Treatment of oil recovery industry wastewater, a typical high pollution strength industrial wastewater (chemical oxygen deman (COD): 21000 mg l-1, biological oxygen demand (BOD): 8000 mg l-1, oil and grease: 1140 mg l-1, total dissolved solids (TDS): 37000 mg l-1, total suspended solids: 2580 mg l-1), was carried out by batch oxidation processes. The optimal mass ratio for H2O2/Fe+2 yielding the highest COD removal was found to be 8.658 corresponding to 200.52 g 1-1 H2O2 and 23.16 g l-1 Fe +2 concentrations for 60 minutes reaction time. Fenton process gave a maximum COD reduction of 86% (from 21000 to 2980 mg l-1) and the combination of UV/H2O2 gave a COD reduction of 39% (from 21000 to 12730). The percentage of removal, after the total reaction time (3.5h), H2O2: 8.4 g l-1 and Fe+2: 0.05g l-1, in the photo Fenton process, corresponded to 81 % of the total initial COD (4200 mg l-1). The oxidative ability of the UV/Fe+2/H2O2 process (81%) was greater than that of the UV/H2O2 process (55%) for 80% diluted wastewater. COD removal efficiency for UV/H2O2 process (COD/H2O2=1/2 (w/w)) was 90%, 55%, and 39 when initial COD was 1050, 4200, and 21000 mg l-1, respectively, whereas COD removal was 943, 2320, and 8270 mg l-1, respectively.
... Shafieiyoun et al. (2011) examined COD removal from organic load removal of landfill leachate. Gunes (2008) studied COD removal from crude oil recovery wastewater. Achievement of 60% of COD removal was demonstrated by Chen & He (2003). ...
... In addition, Shafieiyoun et al. (2011) investigated COD removal from organic load removal of landfill leachate. COD reduction from crude oil recovery wastewater was investigated by Gunes (2008). Furthermore, Chen & He (2003) also proved that oily wastewater can be treated to eliminate 60% of COD. ...
The present study intends to investigate the performance of the Fenton reaction as one of the most efficient (AOPs) in a batch mode for treating wastewater effluent from the edible oil industry, as well as the parameters that influence the reaction, such as pH, hydrogen peroxide (H2O2), and ferrous sulfate heptahydrate (FeSO4.7H2O) doses at various reaction times. The response surface methodology (RSM) was applied with a central composite design (CCD) for optimizing the responses of pollutant removals. The obtained results indicated that the authenticated response to the chemical oxygen demand (COD) removal was 93.52%, at optimum values of pH, FeSO4.7H2O dose, H2O2 dose, and reaction time of 3, 1 g/L, 8.38 g/L, and 50 min, respectively. Furthermore, the authenticated response to oil and grease (O&G) removal was 99.8%, at optimum values of pH, FeSO4.7H2O dose, H2O2 dose, and reaction time of 3, 0.71 g/L, 8.7 g/L, and 37.4 min, respectively. Under these conditions, the residual COD and O&G after Fenton oxidation become 155.4 mg/L and 10 mg/L, respectively.
HIGHLIGHTS
The COD removal was 93.52%, at optimum values of pH, FeSO4.7H2O does, H2O2 dose, and reaction time of 3, 1 g/L, 8.38 g/L, and 50 min, respectively.;
The O&G removal was 99.8%, at optimum values of pH, FeSO4.7H2O does, H2O2 dose, and reaction time of 3, 0.71 g/L, 8.7 g/L, and 37.4 min, respectively.;
The residual COD and O&G after advanced oxidation become 155.4 mg/L and 10 mg/L, respectively.;
... According to the internationally permissible ratios, the detected concentrations of Fe 3þ and Co 2þ are highly toxic to all forms of life, in addition to the fact that previous reports their biological removal from industrial wastewater are very scarce, and therefore these two heavy metals were selected for optimization studies by the hyper active fungal biosorbents. Universally, the heavy metals responsible for environmental contamination are cadmium (Cd 2þ ), cobalt (Co 2þ ), chromium (Cr 6þ ), zinc (Zn 2þ ), nickel (Ni 2þ ), copper (Cu 2þ ), lead (Pb 2þ ), Iron (Fe 3þ ) and mercury (Hg 2þ ), which are generated from different sources and industries as refinery, metal finishing, electroplating, tanning, chemical manufacturing, fertilizer and mining (Dusengemungu et al., 2020 Dincer et al. (2008) for COD, BOD, TSS, ammonia, oil and grease and TDS (21000, 8000, 2580, 69, 1140, and 37000 mg/L) in the refinery wastewater. Interestingly, as presented in Table 1, the pH of all petroleum refining wastewater under study was highly acidic and ranged from pH from 2.5 AE 0.02 to 2.8 AE 0.02 which is far above the legal requirements and promotes the dissolution of toxic metals. ...
... Interestingly, as presented in Table 1, the pH of all petroleum refining wastewater under study was highly acidic and ranged from pH from 2.5 AE 0.02 to 2.8 AE 0.02 which is far above the legal requirements and promotes the dissolution of toxic metals. In line with our data Dincer et al. (2008) note that the pH of petroleum wastewater is equal to 2.50 which can be described as highly acidic. The acidity of these petroleum effluents may be attributed to their higher contents of metals are hydrolysed and then lowers the pH of the water and soil making it unsuitable and causing dangerous effects on terrestrial and aquatic organisms, hence the petroleum industries and refineries wastewater need treatments chemical, physical or biological (Varjani et al., 2020). ...
Myco-remediation of heavy metals using indigenous fungi of different petroleum refining areas in Egypt was applied. Among the physicochemical parameters determined in these refineries effluents, the highest levels of heavy metals were recorded for the most toxic heavy metals Fe3+ and Co2+. The fungal isolates under the isolation codes AHM69 and AHM96 isolated from the mycobiome of Mostorod and Tanta refineries, respectively showed the best bioremoval efficiency toward heavy metals from the real wastewater mixture and polycyclic aromatic hydrocarbons from aqueous solutions. Based on phenotypic and genotypic analysis they were identified as Aspergillus sp. AHM69 and Penicillium sp. AHM96. The optimum conditions for the best bioremoval of Fe3+ and Co2+ from aqueous solutions by Aspergillus sp. AHM69 were live biomass, temperature 45–55 °C, pH 4.5–5.0, contact time 180 min, metal concentration equal to 1000 and 400 mg/L of Fe3+ and Co2+ with live fungal biomass dose of 0.5% and 0.4% with Fe3+ and Co2+, respectively. Concerning to the biomass of Penicillium sp. AHM96, the optimum operation conditions for the best removal of Fe3+ and Co2+ were 45 °C, pH 5.0 and 400 mg/L of Fe3+ with 1.0% biosorbent dosage or 1000 mg/L of Co2+ with 0.5% biosorbent dosage for 180 min as process time. Furthermore, FTIR analysis showed masking, shifting, creating and absenting of different functional groups in the fungal biomass surface of AHM96 and AHM69 strains in the presence of Fe3+ and Co2+ compared to unloaded biomasses. Microscopy with Energy Dispersive X-ray analysis (SEM-EDX) indicated that the removal of Fe3+ and Co2+ by fungi AHM69 and AHM96 was via biosorption and bioaccumulation on the biomass surface. Our results suggested that in the near future, fungal treatment is likely to outperform and replace other chemical and biological treatments in industrial wastewater treatment for oil refining.
... The furfural mineralisation declined to 63% with 40 mg/L Fe +2 . This is in agreement with the previous observations (Tony et al., 2009;Dincer et al., 2008;Zhang and Yang, 2011;Tony et al., 2012). The addition of ferrous ion can increase wastewater turbidity, which prevents the absorption of the UV light, necessary for the photo-Fenton process. ...
... The addition of ferrous ion can increase wastewater turbidity, which prevents the absorption of the UV light, necessary for the photo-Fenton process. Furthermore, ferrous ions can react with OH•, decreasing the attack of OH• on organic molecules and producing compounds that retard the reaction (Neyens and Baeyens, 2003;Dincer et al., 2008;Pignatello et al., 2006). Figure 8 shows the effect of using 1,300 mg/L H 2 O 2 with different amounts of Fe +2 on furfural mineralisation. ...
... With Fe +2 ion concentrations of 0.1 mM, an amount below the maximum discard limit permitted by Brazilian law (0.27 mM), there was 99% degradation of the organic compounds originally present in the wastewater, expressed as total organic carbon (TOC). Dincer et al.(2008) investigated the degradation of wastewater from oil recovery industry by the Fenton, photo Fenton and UV/H 2 O 2 processes. The COD removal efficiency was strongly affected by many factors such as the concentration of H 2 O 2 , Fe +2 and the ratio of organic materials to the Fenton reagents. ...
... required for the photo-Fenton process, (Dincer et al., 2008). ...
In the present work advanced oxidation process, photo-Fenton (UV/H 2 O 2 /Fe +2) system, for the treatment of wastewater contaminated with oil was investigated. The reaction was influenced by the input concentration of hydrogen peroxide H 2 O 2 , the initial amount of the iron catalyst Fe +2 , pH, temperature and the concentration of oil in the wastewater. The removal efficiency for the system UV/ H 2 O 2 /Fe +2 at the optimal conditions and dosage (H 2 O 2 = 400mg/L, Fe +2 = 40mg/L, pH=3, temperature =30 o C) for 1000mg/L load was found to be 72%.
... Increases in pH at basic values and H 2 O 2 concentration up to 2 m mol/L improved dye removal efficiency, but increases in bicarbonate anion UV UV converts hydrogen peroxide into highly reactive hydroxyl radicals hydroxyl radicals attack and decompose viral contaminants concentration decreased it (Benitez et al., 1998;Crittenden et al., 2012). Additionally, it has been claimed that the use of UV/H 2 O 2 and ultrasonic (US) waves to treat dyeing wastewater can enhance color removal (Crittenden et al., 2012;Gunes, 2008). Recently, researchers compared the efficacy of UV/H 2 O 2 and US/UV/H 2 O 2 strategies for removing malachite green as a traditional pollutant from the textile sector (Crittenden et al., 2012;Neyens & Baeyens, 2003;Niaounakis & Halvadakis, 2006). ...
... This is mainly caused by the fact that when pH is higher than 3, ferrous and ferric hydroxides are formed which inhibit the reaction between Fe 2+ and H 2 O 2 and thus the hydroxyl radicals production. On the other hand, at very lower pH, excessive H + reacts with H 2 O 2 to produce H 3 O 2 +, which is stable and cannot react with iron (II) to form the HO• species (Dincer et al., 2008;Patel and Shah, 2013;Chen et al., 2019). ...
... This is mainly caused by the fact that when pH is higher than 3, ferrous and ferric hydroxides are formed which inhibit the reaction between Fe 2+ and H 2 O 2 and thus the hydroxyl radicals production. On the other hand, at very lower pH, excessive H + reacts with H 2 O 2 to produce H 3 O 2 +, which is stable and cannot react with iron (II) to form the HO• species (Dincer et al., 2008;Patel and Shah, 2013;Chen et al., 2019). ...
This project focuses on the suitability of Fenton and photo-Fenton processes for the degradation of methylene blue dye in terms of COD removal and it is optimized for experimental parameters such as pH, H 2 O 2 concentration, FeSO 4 .7H 2 O concentration and contact time. The Fenton process and photo-Fenton process is found to be effective under pH 3. The maximum efficiency of COD removal for 50 mg/L of Methylene blue is attained at optimum concentration of 10 ml of H 2 O 2 , 50 mg/L of Fe 2+ and contact time of 30 minutes. The photo-Fenton oxidation process is also being carried out and it is also optimized for experimental parameters. The efficiency of COD removal for methylene blue is attained at optimum concentration of 8 ml of H 2 O 2 , 50 mg/L of Fe 2+ and at a contact time of 30 minutes. Finally, on comparing both the processes, the best method with maximum removal efficiency is identified as photo-Fenton process for degradation of dye. At fully optimized condition, the efficiency of Fenton process is 65% and that of photo-Fenton is 82%, which is 17% higher than the Fenton process.
... mg /l. Dincer et al. (20) reported that OOMW has high values of COD equaled to 21000 mg/l. ...
... When chlorine oxidation is used to treat this waste water, excessive chlorine needs to be added, so it is usually not used to treat high-concentration, refractory industrial waste water.The Fenton reage nt method is currently widely used, which can couple phenolic substances toproduce phenolic polymer s, which are finally converted into CO 2 . Dincer [10] used H 2 O 2 /Fe 2+ , UV/H 2 O 2 /Fe 2+ and UV/H 2 O 2 to tre at waste water. The result showed that the COD removal rate was 81%, and the treated water met the r equirements of biochemical treatment. ...
Shale oil refinery waste water was a kind of high-concentration organic waste water with many types of pollutants and complex components. It contained environmental pollutants such as petroleum, volatile phenols, organic nitrogen, naphthenic acid compounds and fused ring aromatic hydrocarbons. If it is discharged directly without treatment, it will cause serious harm to the environment, and it must be treated before it can be discharged. At present, the treatment methods of shale oil refinery waste water mainly include physical treatment, chemical treatment, physical and chemical treatment and biological treatment. This paper studied the treatment technology of shale oil refinery waste water.
... 3,4 For practical industrial settings, a large amount of Fe 2+ (18-410 mmol/L) and H 2 O 2 (30-6,000 mmol/L) are generally required in order to produce , OH of sufficient concentrations. 1,[5][6][7] Because of the high efficiency of Equation 1 but low efficiency of Equation 2, an excessive amount of Fe 3+ ions is generated, which leads to the formation of sludge (iron cement) and therefore catalyst poisoning ( Figure S1). 8 On the other hand, too much H 2 O 2 used in the AOPs will corrode the equipment and greatly increase the operating costs. ...
Advanced oxidation processes (AOPs) are widely proposed for treating persistent pollutants by the ⋅OH radicals generated from H2O2 decomposition. However, their broad applications in practical settings have been hampered by the low efficiency of H2O2 decomposition. Here, we report that metal sulfides (MoS2, WS2, Cr2S3, CoS2, PbS, or ZnS) can serve as excellent co-catalysts to greatly increase the efficiency of H2O2 decomposition and significantly decrease the required dosage of H2O2 and Fe²⁺ in AOPs. Unsaturated S atoms on the surface of metal sulfides can capture protons to form H2S and expose metallic active sites with reductive properties to accelerate the rate-limiting step of Fe³⁺/Fe²⁺ conversion. The efficiency of AOPs involving co-catalysts can be further enhanced by visible-light illumination thanks to the sensitization of organic pollutants. This discovery is expected to drive great advances in the use of AOPs for large-scale practical applications such as environmental remediation.
... Oleh karenanya, pengetahuan terhadap mekanisme kimia pada reaksi fotokimia akan bermanfaat dalam merencanakan sistem pengolahan secara fotokimia untuk air yang tercemar (Yulianto, Handayani, & Silviana, 2005). (Gunes, 2008) Proses Fenton adalah metode untuk degredasi senyawa organik dengan reaksi antara hydrogen peroksida dengan ion besi dalam kondisi penyinaran atau tanpa penyinaran Ultra Violet (UV) yang menghasilkan hydroxyl radical (Huang et al., 2009). ...
Air lindi dari proses rembesan air sampah organik yang ada pada rumah kompos umumnya mengandung beban pencemar yang sukar terurai. Air lindi tersebut akan menyebabkan masalah terhadap lingkungan jika dibuang langsung ke badan air apabila tanpa adanya pengolahan. Penanganan beban pencemar ini dapat dilakukan dengan metode Advanced Oxidation Process (AOP). Salah satu dari metode AOP adalah FotoFenton. Penelitian ini bertujuan untuk mengetahui efisiensi pengolahan air lindi dengan metode fotofenton secara resirkulasi berdasarkan perbandingan molar H2O2:FeSO4 dan Debit aliran resirkulasi. Pada penelitian ini, parameter yang diamati meliputi TSS, COD, BOD, Total N, dan PO4. Pada penelitian batch yang dilakukan dengan 5 liter air lindi ditetapkan variabel perbandingan molar H2O2:FeSO4 dengan variasi 10:0,10, 10:0,15, 10:0,20, 10:0,25, dan 10:0,30 dan variabel Debit aliran resirkulasi dengan variasi debit 0,2, 0,25, 0,34, 0,4, dan 0,6 liter/detik. Selain secara batch, penelitian ini juga dilakukan percobaan kontinu fotofenton secara resirkulasi dengan variabel terbaik dari proses batch. Berdasarkan penelitian, efisiensi pengolahan TSS, COD, BOD, Total N, dan PO4 pada lindi menggunakan fotofenton secara resirkulasi masing-masing sebesar 91%, 87%, 70%, 65% dan 79% pada perbandingan molar 10:0,30 dengan debit aliran 0,6 liter /detik. Kata kunci: Air lindi, fosfat, fotofenton, limbah organik, total nitrogen, total suspended solid (TSS). Leachate from seepage process of organic waste water in compost houses generally contains pollutant load which is difficult to decompose. Leachate will cause problems to the environment if it is discharged directly into water if there is no treatment. The handling of these pollutants can be done by the Advanced Oxidation Process (AOP) method. One of the AOP methods is PhotoFenton. This study aims to determine the efficiency of leachate water treatment with the photofenton method by recirculation based on H2O2: FeSO4 molar ratio and recirculation flow discharge. In this study, the parameters observed included TSS, COD, BOD, Total N, and PO4. In a batch study conducted with 5 liters of leachate water, the molar ratio variables of H2O2: FeSO4 were determined with variations of 10: 0.10, 10: 0.15, 10: 0.20, 10: 0.25, and 10: 0.30 and variable discharge of recirculation flow with discharge variations of 0,2, 0,25, 0,34, 0,4, and 0,6 liter / second. Aside from being batch, this research also carried out a continuous fotofenton recirculation experiment with the best variables from the batch process. Based on the research, the processing efficiency of TSS, COD, BOD, Total N, and PO4 in leachate using photofenton by recirculation were respectively 91%, 87%, 70%, 65% and 79% at a molar ratio of 10: 0.30 with discharge flow of 0.6 liters / second. Keywords: fosfat, leachate, organic waste, photofenton, total nitrogen, TSS.
... In addition, some natural chemicals that cause hardness such as calcium and magnesium. • The average COD concentration was about 4000 mg/L and Dincer et al. (2008) reported that the COD concentration in the oilfield-produced water and oil refinery wastewater was 21000 mg/L. Thus, it is considered a high challenge to remove it by traditional treatment methods. ...
Oilfield wastewater or produced water is a complex mixture contains oil, organic and inorganic matter and other compounds dissolved in water that ranges from fresh to brine. Discharging produced water pollute soil surface and underground water and create environment hassle. The objective of this study is to investigate and summarize the novel method of fluidization processes, used for the treatment of oilfield produced water and oil refinery wastewater. Characteristics of oilfield produced water and oil refinery wastewater from different field and various methods for treating these wastewaters are discussed. Oilfield produced water and oil refinery wastewater are strongly acidic (pH 3-4), have a high chemical oxygen demand (1200-2600 mg/L), high polyphenol content (23 mg/L) and are highly variable. Primary attention is focused on the fluidization treatment of oilfield produced water and oil refinery wastewater, mainly by inverse fluidization. Finally, areas where further research and attention are required are identified.
... N-pentane 99% (CAS Number 109-66-0) was used in the sample preparation for GC-MS test. COD over measuring issue influenced by H 2 O 2 in the taken samples resolved from MnO 2 addition(CAS Number 1313-13-9) to samples [8,39,40]. ...
The hybrid treatment techniques have been proven that could be a proper solution to the metalworking fluid (MWF) wastewaters disposal challenge. Hence, this investigation was conducted aim to the assessment of chemical addition-dissolved air floatation (CA-DAF) unit followed with a heterogeneous photocatalytic (PC) process as UV/H2O2/ZnO to treat MWF wastewater produced in one of the central industrial estates in the Middle East. The CA-DAF unit was implemented as trial and errors and had an appropriate efficiency. However, the environmental discharge standards were not achieved only by this unit, so that, a PC process considered for this purpose in a pilot-scale reactor. And also, Chemical oxygen demand (COD), total petroleum hydrocarbons (TPHs) were considered as physicochemical parameters to analyze the applied photochemical reaction throughout the concentrations of ZnO and H2O2, and pH value as variables of the study. The ideal and optimized conditions were observed at pH 10, 600 mg l-1 of ZnO, and 13.11 g l-1 of H2O2 via 99.87% and 97.9% reduction rates in total COD and TPH, respectively. These removal rates were obtained for this integrated strategy under the optimized reaction. By evaluating the synergistic effect, it was found that UV/ZnO could be a predominant reaction in this process. The organic and intermediates analysis appeared 78.46% reduction for all detected organic matters. Besides, PC generation of bis phthalate, mono phthalate, benzene, and benzoic acid to 2,6-bis (1,1-dimethylethyl)-4-mthyl phenol was the reason of the residual phenolic compound concentration in the reaction solution with low removal rate. The kinetic study showed that this reaction could be well fitted with the pseudo-first-order kinetic model by R
2
equal with 0.973 and 0.988 in turn for COD and TPH. The expenditures to treat 1 m3 of the CA-DAF was estimated at 5.335 us$ via cost analysis. Finally, the collected findings indicate that CA-DAF integrated with UV/H2O2/ZnO can be an efficient approach in the MWF wastes disposal or treatment for reuse.
... The present findings seem to be consistent with other research which concluded that, there is an optimum value for H 2 O 2 /Fe 2+ molecular ratio, above or below this value, it decreases the effectiveness of the process 42,43,47 . The negative effect can be explained by that, adding of ferrous ions increases the optical density of the solution, which hinders the absorption of the UV light, required for the photo-Fenton process 48 . Additional ferrous ions can react with hydroxyl radical decreasing the offensive of hydroxyl radical on NH 3 substrates (according to Eq. 7). ...
Background: Agriculture is one of the most important sources of national income for Egypt. But it is one of the most important human activities contaminated watercourses. Egypt suffers from a severe shortage, that reflected on the water quality and the amount of pollution in the watercourses. Several studies have shown the contamination of many watercourses in Egypt with different nitrogen forms. The advanced oxidation processes (AOPs) one of the most competent methods in the disposal of pollutants. The effect of AOPs using UV, UV/H 2 O 2 , Fenton and photo-Fenton treatment on disposal NH 3 were investigated at laboratory scale. Experiments were conducted to optimize the operating variables like pH, H 2 O 2 conc. and H 2 O 2 /Fe 2+ molar ratio. Results: The removal rate of NH 3 obeys the following sequence: photolysis < UV/H 2 O 2 < Fenton < Photo-Fenton. The Photo-Fenton treatment had removed 92.11% of NH 3 content of the sample, at that conditions (900 mg L-1 H 2 O 2 , H 2 O 2 /Fe 2+ molecular ratio=20, and pH=3). Conclusions: Most AOPs was capable of NH 3 disposal with varying degrees of success. The most effective processors were the photo-Fenton, but it needs to reduce the pH value. Which, requiring many additional and costly economic treatments. Therefore, it is necessary to conduct other experiments to increase the effectiveness of that process at pH 7.
... The main function of coagulation is to prevent RO membrane from the deposition of particulate matter [6]. Coagulation can be used as a method for the removal of many substances that cause turbidity, including oils [13], clays [14], and microorganisms [15]. Usually, coagulation is followed by sedimentation. ...
The objective of this work is to simulate pretreatment steps on a laboratory scale with the purpose of producing a higher quality permeate for feed reverse osmosis process. Pretreatment steps involved in this work are a combination of physical and chemical processes, such as coagulation-flocculation, sand filtration, and microfiltration. Samples of seawater next to Itaqui thermoelectric power plant in Maranhão, State of Brazil, powered by coal, were collected and characterized. The characterization indicated high levels of turbidity, which is unusual for seawater, indicating the need of pretreatment to reverse osmosis. The combination of polyaluminum chloride dosages of 30 mg/L and 0.3 mg/L of Nalclear 8,173 anionic polymer allowed the reduction of turbidity values to below 1 Nephelometric Turbidity Unit (NTU). The use of coagulation and microfiltration membranes provided values of silt density index next to 3, while with sand filter, the silt density index values were higher than 4.
... Table (2) showed that COD ranged from 17306 to 191000 mg/l with average of 130768 mg/l, while BOD varied between 9183 and 70000 mg/l with average of44727 mg/l. The problems connected with OMW depend on their COD values as high as 21-300 g/l and BOD (13-120g/L) (Cossu, et al., 1993;Cabrera, et al.,1996;Niaounakis and Halvadakis, 2004;Khoufi,et al., 2006;Tsagaraki,et al.,2007;De Marco, et al., 2007;Dincer, et al.,2008;Gargouri, et al.,2013).These values are 200 to 400 times higher than municipal water (Tabet, et al.,2006). ...
Growth of the olive oil production in Aljouf region, the northern part of Saudi Arabia, has been accompanied by an increase in the volume of olive oil mill wastewater, hereafter noted as OMW (acque reflue in Italy; alpechin in Spain; katsigaros in Greece; zebar in Arab countries) which is produced seasonally by a large number of small olive mills scattered throughout the region. The generation rate of OMWW is very high and concentrated in a short period of time (October-January).The uncontrolled disposal of OMW on soil represents a major social, economic, and environmental problem .The purpose of this study was to evaluate the microbiological and physico-chemical quality which is crucial to decide the best way to treat, dispose or reuse of OMW.
... Furthermore, the mineralization of organic matter increased with the decreasing Fe concentration. This is often attributed to the competitive reactions of H 2 O 2 with the excessive Fe 2+ ions to form Fe 3+ , which leads to lower degradation rates [3,29]. On the other hand, it was found that the optimal H 2 O 2 concentration corresponded to a ratio H 2 O 2 /COD = 2 with a H 2 O 2 /Fe 2+ ratio of 50 (Fig. 1b). ...
To undertake a better water management in Oil&Gas sector, it is essential to decrease the wastewater generation by increasing the current reused water rates. Focused on this motivation, this study presents the performances of solar-assisted photo-Fenton and heterogeneous photo-catalysis on refinery wastewater treatment for reuse purposes with the aim of zero discharge. While initial tests were made on synthetic refinery wastewater, real case studies were performed with two types of refinery effluent in order to test the feasibility of using AOPs either as a secondary or tertiary treatment. Even though heterogeneous photo-catalysis and a combined process showed promising results for the treatment of the refinery effluents, photo-Fenton treatment revealed a superior effectiveness for application in both secondary and tertiary treatment, considering the improvements on TOC removal, toxicity and biodegradability. Photo-Fenton as secondary treatment resulted as efficient as the biological treatment, reaching final TOC values ca. 20 mg/L and 88% of COD removal presenting values lower than those achieved after the biological treatment. Moreover, a marked increase in the BOD 5 /COD ratio from 0.38 to 0.83 was obtained. Furthermore, as a tertiary treatment, photo-Fenton process either with H 2 O 2 /COD = 10 and H 2 O 2 /Fe ²⁺ = 50 or H 2 O 2 /COD = 4 and H 2 O 2 /Fe ²⁺ = 10 provided a final TOC value <4 mg/L. This result reveals the possibility to reuse the effluent in the refinery plant, thus increasing the sustainability.
... Ultraviolet radiation is used to cleave the O-O bond in hydrogen peroxide and generate the hydroxyl radical [36]. Efficiency of the UV/H2O2 process for COD removal is dependent on initial wastewater pollution strength or dilution of wastewater, hydrogen peroxide concentration and reaction time [37]. According to Joshi et al. [38], the use of UV/H2O2 for decolourization increase the rate and strength of oxidation, in the same time it is Environment-friendly application but the cost of producing UV irradiation does not compensate for the increase. ...
The selection of an effective water treatment technology is the important issues that relatively dealing with water pollution problems, some pollutants need more than the conventional facilities to be treated and discharged within the national standards. This
study highlights some of the advanced treatment methods related to chemical oxidation, which is used in the treatment of some types of pollutants such as heavy metals, pesticides, dyes, etc. and demonstrate their effectiveness in treatment by reviewing what has been
concluded in a number of studies in this range.
... The negative effect can be explained as follows: the addition of ferrous ions increases wastewater brown turbidity during the photo-treatment, which hinders the absorption of UV light (Dincer et al. 2008). Excess ferrous ions can react with hydroxyl radical according to Eq. 3, decreasing the attack of hydroxyl radical on organic substrates. ...
Your article is protected by copyright and all rights are held exclusively by Springer-Verlag Berlin Heidelberg. This e-offprint is for personal use only and shall not be self-archived in electronic repositories. If you wish to self-archive your article, please use the accepted manuscript version for posting on your own website. You may further deposit the accepted manuscript version in any repository, provided it is only made publicly available 12 months after official publication or later and provided acknowledgement is given to the original source of publication and a link is inserted to the published article on Springer's website. The link must be accompanied by the following text: "The final publication is available at link.springer.com". Abstract The application of advanced oxidation process (AOP) in the treatment of wastewater contaminated with oil was investigated in this study. The AOP investigated is the homogeneous photo-Fenton (UV/H 2 O 2 /Fe +2) process. The reaction is influenced by the input concentration of hydrogen peroxide H 2 O 2 , amount of the iron catalyst Fe +2 , pH, temperature , irradiation time, and concentration of oil in the waste-water. The removal efficiency for the used system at the optimal operational parameters (H 2 O 2 =400 mg/L, Fe +2 = 40 mg/L, pH=3, irradiation time=150 min, and tempera-ture=30 °C) for 1,000 mg/L oil load was found to be 72 %. The study examined the implementation of artificial neural network (ANN) for the prediction and simulation of oil degradation in aqueous solution by photo-Fenton process. The multilayered feed-forward networks were trained by using a backpropagation algorithm; a three-layer network with 22 neurons in the hidden layer gave optimal results. The results show that the ANN model can predict the experimental results with high correlation coefficient (R 2 =0.9949). The sensitivity analysis showed that all studied variables (H 2 O 2 , Fe +2 , pH, irradiation time, temperature, and oil concentration) have strong effect on the oil degradation. The pH was found to be the most influential parameter with relative importance of 20.6 %.
... The negative effect can be explained as follows: the addition of ferrous ions increases wastewater brown turbidity during the photo-treatment, which hinders the absorption of UV light (Dincer et al. 2008). Excess ferrous ions can react with hydroxyl radical according to Eq. 3, decreasing the attack of hydroxyl radical on organic substrates. ...
... (Yavuz et al., 2010) showed that the most efficient method was the electro-Fenton process followed by the electrochemical oxidation using born doped diamond (BDD) anode while the electrocoagulation was found to be ineffective for the treatment of petroleum refinery wastewater (PRW). Ramteke and Gogate (2015) reported that using combined Fenton and ultrasound achieved 95% COD removal from petroleum wastewater at pH 3. Dincer et al. (2008) evaluated the applications of the Fenton and photo-Fenton processes for the treatment of oil recovery industry wastewater. Under the most favorable conditions for the Fenton process (pH 3, Fe 2+ : 23.16 g L -1 and H 2 O 2 : 200.52 g L -1 , a mass ratio of 8.658 for H 2 O 2 : Fe 2+ ), 86% of the initial COD was removed (from 21000 to 2980 mg L -1 ) from the petroleum wastewater. ...
Petroleum wastewater generation is one of the main pollutants associated with oil refineries processes. The petroleum wastewater usually contains a complex variety of materials and organic compounds. Dedicated treatment facilities are required before the petroleum wastewater can be discharged to the environment. Researchers worldwide are still searching for a total solution to solve petroleum wastewater problem. In this chapter, different chemical treatment methods for the petroleum wastewater including coagulation-flocculation, Fenton and electro-Fenton oxidation, photocatalyst oxidation, and advanced oxidation processes are reviewed and discussed. Nevertheless, the efficiency of each process was also evaluated. It can be concluded that the performance of these processes is mainly attributed to petroleum wastewater type and initial organic concentrations whereas treatment performance weakens reported at higher initial concentrations of pollutants.
... To treat wastewaters of various nature and composition, a wide range of physicochemical methods are used today [7][8][9][10][11][12][13][14]. However, the soy milk production wastewaters are hard to treat since they are dispersed colloid systems with long-term relative thermodynamic stability. ...
The electrokinetic phenomena were studied on model systems represented by finely dispersed water emulsions imitating the wastewater of soy milk production. The study has shown the presence of a suspension effect and its dependence on various factors. The results have proven that the coagulating suspension on the basis of electric arc furnace (EAF) dust is an effective way to treat soy milk production wastewater. The interaction of system components is stipulated by opposite charges of the particles in coagulating suspension and emulsion.
Plastic pollution is a global problem that is very dangerous if not handled appropriately and systematically. These plastics can enter the environment and will degrade into microplastics due to environmental factors such as light, temperature and humidity. Microplastics are degraded plastics with a size of <5 mm. This microplastic is very dangerous if ingested by living creatures. One of the impacts can cause digestive disorders, cancer and many more. The aim of this research is to obtain an appropriate method for extracting polystyrene microplastics from water samples. The method used is the WPO (wet peroxide oxidation) extraction method. This method uses two solutions, namely Fe(II) 0,05 M as a catalyst to accelerate the oxidation reaction of impurities and H 2 O 2 30% as an OH• producing material which function to oxidize impurities. In the procedure, variations in Fe(II) concentration and heating temperature were carried out. The optimum results obtained were Fe(II) 0,075 M and a heating temperature of 75°C. Apart from that, microplastic characterization was also carried out using FTIR (Fourier Transform InfraRed). Characterization using FTIR shows that the specific functional groups possessed by polystyrene are C-H bending, C=C stretching and C-H stretching at wave numbers 758 cm -1 , 1600,97 cm -1 and 2931,90 cm -1 , respectively.
The oil and gas industry produces significant amounts of waste including petroleum wastewater, waste drilling fluid, and oil sludge. Bioremediation uses microorganisms and plants to degrade toxic substances. This offers a cost-effective and less labor-intensive solution for managing waste and recovering contaminated areas. Methanogens play a key role in the production of biohythane, a high-value fuel composed of biomethane and biohydrogen. In cooperation with hydrocarbon degraders and fermentative bacteria, they can make the biomethanation processes thermodynamically favorable under anaerobic conditions. This study reviews the use of H2-dependent methylotrophic methanogens for bioremediation in the oil and gas industry, highlighting their effectiveness in hydrocarbon methanogenesis in various environments. We have also addressed the importance of methanogens in shale reservoirs, oil-produced water, petroleum refinery oil sludge, and coal-bed methane reservoirs. This review provides a comprehensive analysis of methanogenic bioremediation and its effectiveness at mitigating environmental pollution. It discusses the challenges faced in practical implementation, such as ensuring methanogen survival and activity under harsh conditions. The factors influencing hydrocarbon methanogenesis and microbial community structure are not fully understood, making it challenging to ensure the survival and activity of methanogens under harsh conditions. Future research directions and technological advancements are required for practical implementation of consolidated methanogenic bioprocessing of petroleum refinery oil sludge for biohythane production. Thus, this review explored the potential of methanogens as a sustainable waste management resource in the oil and natural gas industries.
Oil spills are of great concern because oily wastewater disrupts the aquatic ecosystem, causes mutations in animals, contaminates surface water resources, and causes diseases such as cancer in humans. Current efforts are geared towards recovering spilled oil from aquatic environments and ensuring the effective separation of oil and water in the collected emulsion. After oil separation from the emulsion, a polishing step is required to treat the residual oil in the water before discharging the effluent into the aquatic environment. Oily wastewater treatment methods such as electrochemical treatment, membrane filtration, flocculation, membrane bioreactor, and advanced oxidation processes are intricate, costly, and achieve varying removal efficiencies. Adsorption using environmentally friendly and cost-effective adsorbents is seen as an attractive option. This paper provides an overview of oily wastewater treatment using adsorption. Recent adsorption studies have focused on optimizing parameters such as adsorbent dosage, pH, initial oil concentration (IC), and contact time (CT) to enhance treatment efficiency. Principal component analysis was conducted based on previous studies to understand the key parameters influencing adsorption and gain insights into the interactions between these operating variables. The findings indicated a strong positive correlation between the first principal component (PC1) CT and IC, with coefficients of 0.704 and 0.702, respectively. This suggests that positive values of CT and IC significantly contribute to the variance in PC1, meaning that the variation in PC1 is closely linked to the variation in CT and IC. New materials could be produced to enhance selectivity to target specific pollutants in oily wastewater.
The COD concentration in petroleum wastewater (PWW) varies widely depending on the type of crude oil and the method used for refining. Coagulation provides a feasible method for removing turbidity, colour, TSS, and TP from wastewater. However, this technique has its own limitations when dealing with highly COD-concentrated PWW above 6000 mg/l. In this paper, the traditional coagulation technique and its limitations are discussed. This review provides insights into the latest developments of coagulation for COD treatment from highly concentrated PWW. The initial pollutant load of PWW was discovered to be one of the main considerations of coagulation treatment efficiency. It was revealed that a modified coagulant known as PFASi is the best approach to treat highly COD-concentrated wastewater (up to 20000 mg/l).KeywordsCoagulationFlocculationPetroleum wastewaterCODAdvanced technologies
In this paper, a time-conserving fragility curve formulation methodology for extreme events is discussed. Uncertainty is a parameter that has a significant effect on the probabilistic estimations of infrastructure failures. Structural damages to civil infrastructure range from minor defects to collapse relative to serviceability or restoration measures. In this paper, earthquake-induced landslides are used as a sample case study, to study empirical methods of fragility curve formulation. Method of maximum likelihood and best-fit regression methods are applied to an extreme event, and fragility curves are derived. Monte Carlo stimulation is applied to analyse the behaviour of uncertainty parameter concerning standard sections of highway and railway embankments. Finally, the coefficient of determination was calculated to illustrate the correlation between developed curves and data points. The proposed method suggests an optimum method to quantify the failure probability from an available data sample or a real incident-based data sample, which is computationally very effective. Improvement in vulnerability estimations provides high maintenance and efficient restoration schemes for transportation networks which are prone to extreme events such as landslides.KeywordsFragility curvesEarthquake-induced landslidesMaximum likelihoodMonte Carlo
Residential apartment buildings are widely implemented in Sri Lanka due to rapid urbanization and land scarcity. The confined spaces and controlled ventilation in such apartments could result in adverse health effects, including Sick Building Syndrome (SBS). Because of the usage of chemical products such as incense sticks in such compact spaces for religious activities in South Asia, SBS can occur. This study is one of the first field studies to establish a connotation between the indoor air quality of apartment buildings in Colombo, Sri Lanka, with various chemicals, including incense products and SBS. Measurements were taken from multiple locations in 50 apartments of various indoor environment parameters. Significant Total Volatile Organic Compound (TVOC) concentrations (up to 4.500 ppm) were associated with the use of chemicals, particularly cube-type incense products. Higher CO2 concentrations were associated with migraine and headaches. The relationship between chemical and incense products with higher levels of TVOC and SBS symptoms calls for urgent attention of the key urban planning stakeholders in Sri Lanka to improve ventilation and avoid using such products indoors.KeywordsSick Building SyndromeIndoor air pollutionIncense productsUrban high risersTVOC concentration
Tannery wastewater effluent (TWE) consists of a variety of complex structured compounds having very low biodegradability. Few attempts have been made to treat real-time TWE consisting of complex compounds and find the intermediate compounds formed during the HC+PAA+ FeSO4.7 H2O treatment system. Therefore, a pilot scale study has been conducted on an orifice-embedded hydrodynamic cavitation reactor for treating real-time TWE. Liquid chromatography-high resolution mass spectrometry (LC-HRMS) has been carried out to identify the specific compounds present in TWE before and after treatment. Response surface methodology (RSM) – Box-Behnken design (BBD) obtained maximum COD, TDS and turbidity removal efficiency of 72.36%, 94.54% and 98.89%, respectively, at cavitation time-97.5 min, inlet pressure-7.5 bar, pH-2, orifice diameter-0.5 mm, PAA dosage-17.5 g/L, and PAA /FeSO4.7 H2O-2:1 ratio. The reaction rate constant was increased from 2.455 × 10⁻³ to 12.75 × 10⁻³ min⁻¹ when AOPs were combined with HC. The study concluded that the degradation using HC+PAA+ FeSO4.7 H2O successfully increased the biodegradability of the TWE without forming any toxic by-products.
In this work, the performance of integral coagulation-photocatalytic process was evaluated, and compared to the individual processes (coagulation and photocatalytic) for the oil removal (175 mg/L) from oilfield wastewater. As a natural coagulant, peels of sunflower seeds was applied and the impact of the important parameters like coagulant dose (from 0.5 to 6 g/L), pH (from 2 to 12), and temperature (from 20 to 60 oC) were studied in coagulation experiments. Additionally the impact of different parameters like the concentration of H2O2 (hydrogen peroxide) from 50 to 250 mg/L, the TiO2 dose from 20 to 150 mg/L, pH from 2 to12, temperature from 20 to 60 oC, and irradiation time from 10 to 120 min were tested in the photocatalytic process (UV/TiO2/ H2O2). The results revealed that, the highest oil removal efficiency was 46.86 % at the optimal conditions of the coagulation process, whereas, the highest oil removal efficiency was 97.71 % at the optimal conditions of photocatalytic process. However, the best removal were obtained with an integral coagulation-photocatalytic process where the removal efficiency of oil reached 99.99% and achieved the allowed requirement range of discharge OPW (oil < 5 mg/L) to reinjection in a reservoir of oil. Furthermore, the integral treatment process was the most effective process under natural conditions and showed a higher reduction of oil (0.01 mg/L) at a short radiation time. The suggested process was found useful and can be considered economical for oilfield wastewater treatment.
Large quantities of effluents containing oil, water, and oily sludge are produced from the activities and processes in the petroleum industry. The amount of waste in this industry is growing daily with increasing demands. This wastewater includes large amounts of organic and inorganic pollutants that Draining of these effluents pollutes the environment. These contaminants also damage the human and living organism’s health. The acceptable refining of oily wastewater is a current challenge to the petroleum industry. Using solar-based photocatalysis as a new, cost-effective, environmentally friendly, and highly effective process to treat petroleum wastewater is a smart way. This chapter explores the performance of photocatalysis oxidation methods for the treatment of petroleum refinery wastewater. Also, the petroleum wastewater sources and their characteristics are discussed. The influence factors, benefits, and negative aspects of using photocatalysis for this aim are mentioned processes.
The present research was undertaken to investigate the potential of
electrocoagulation (EC) and electrochemical oxidation (EO) techniques for
treating petroleum refinery wastewater. Different types of electrodes have
been used in both electrocoagulation and electrochemical oxidation. In
electrocoagulation, aluminium and mild steel were used as the anode. While
in the electrochemical oxidation, ruthenium oxide coated titanium (RuO2/Ti)
was used as the anode.
In electrocoagulation, the experiments were conducted in a batch
reactor. The effect of the operating parameters, such as the current density,
pH, supporting electrolyte, treatment time, and anode material, was examined.
The progress of the pollutant removal was measured through COD
measurement. The electro-coagulation mechanism was modeled using
adsorption isotherms. The sludge generated during electrocoagulation was
analyzed by scanning electron microscopy (SEM) coupled with the energy
dispersive analysis of X-rays (EDAX). The Fourier transform infrared (FTIR)
spectroscopy analysis was used for the liquid effluent analysis. The results
showed a maximum percentage COD removal of 87% can be achieved under
optimum experimental conditions. The energy consumption and anode
dissolution were 15 kWh/kg and 622 mg/dm3
respectively, within 40 min of
vi
treatment time. The metal hydroxide, and the gases released during the
electro-coagulation process, eliminated the pollutants in the wastewater. The
adsorptability of the pollutants in the wastewater on the surface of flocs was
modeled using the Langmuir, Tempkin, Freundlich, and Dubinin–
Radushkevich models. The Freundlich isotherm model matches satisfactorily
with the experimental observations for mild steel and aluminium anodes.
In electrochemical oxidation, the experiments were carried out in
batch, and batch recirculation systems. The study focus on evaluating
different operating parameters that affect the performance of the treatment
process to produce high quality water. In a batch electro-oxidation treatment,
the optimized conditions were the current density of 30 mA/cm2
, pH of 8,
supporting electrolyte of 2 g/L, and treatment time of 120 minutes. Under the
optimal condition, the energy consumption of 69 kWh/kg, mass transfer
coefficient of 0.006164 cm/s, and a COD removal efficiency of 92 %, were
obtained. Batch recirculation experiments were carried out in a tubular
electrochemical reactor. The performance of Tubular Electrochemical Reactor
(TER) has been investigated using Residence Time Distribution (RTD) and
Computational Fluid Dynamics (CFD) studies, which give the flow dynamic
behaviour of the electrolyte inside the reactor. The results show that an
increase in the flow rate has a considerable effect on the flow dynamics, and
brings about more turbulence, which is very helpful in increasing the mass
transfer coefficient between the electrode and the fluid flow. Also, the results
obtained show positive influence of the mesh electrode on the flow dynamics
vii
behavior. The presence of dead volume and short circuiting in the reactor
decreased with an increase in the flow rate. The performance of the TER was
experimentally validated by studying the mass transfer and the color removal
efficiency and the results show an improvement at higher flow rates. The
treatment of petroleum refinery wastewater using batch recirculation
experiments show about 84% of COD removal under optimum conditions.
Further the result shows that an increase in the flow rate decreases the energy
consumption, and enhances the mass transfer coefficient. The increase in the
flow rate (30 to 120 L/hr) resulted in considerable improvement of the current
efficiency, (CE), mass transfer coefficient, (km) and specific energy
consumption, (SEC).
The thesis has been divided into five chapters:
Chapter 1 gives an introduction on the petroleum industry, the
usage, recycle and reuse of water in the typical petroleum refinery, the current
regulation of discharge limits for petroleum effluents and various treatments
available to treat the petroleum effluent are discussed. Introduction
electrocoagulation and electro-oxidation processes, advantages of
electrochemical techniques in environmental protection and the purpose of
this study are presented.
Chapter 2 presents a survey of the most important and prominent
literature on the area of the research, the recent regulations for chemical
constituents and processes, various aspects to improve petroleum industry to a
viii
remarkable level and impact of petroleum refinery wastewater on the
environment are also discussed in this chapter.
Chapter 3 presents the wastewater characterization then materials,
electrochemical experimental setup, procedures, and conditions used to treat
the effluents by electrocoagulation and electrochemical oxidation.
Chapter 4 presents the results and discussion; this chapter is
focused on the electrocoagulation and electrochemical oxidation ability for
wastewater treatment. The effects of the operating conditions on the
performance of this process are presented. Adsorption isotherm models for
electrocoagulation process are proposed. The results of residence time
distribution (RTD) and computational fluid dynamics (CFD) simulation
studies are given to evaluate the performance of tubular electrochemical
reactor for effluent treatment.
Chapter 5 summarizes the experimental and theoretical
investigation and the assessment of the treatment processes were performed.
This chapter gives the conclusion made based on the analysis and further future work.
Large quantities of wastewater generate from refineries in the process of crude oil usage, distillation, and cooling systems. The wastewater samples need to be treated before disposing into the environment. Disposal of the untreated refinery wastewater causes problems for the water sources and environment. The aim of this work was to study the characteristics, treatment techniques, and limitations of refinery wastewater treatment. A number of tables were prepared to summarize and review wastewater characteristics, treatment process, and the operational limitations. Results revealed that values of some parameters such as biochemical oxygen demand (BOD), chemical oxygen demand (COD), phenols, oil and grease, and total suspended solids (TSS) were 40.25 mg/L to 8000 mg/L, 80 mg/L to 21000 mg/L, 3.5 mg/L to 128 mg/L, 12.7 mg/L to 50000 mg/L, and 22.8 to 2580 mg/L, respectively. Numerous treatment technologies were used for the treatment of refinery wastewater. Treatment techniques have benefits, weaknesses, and operational limitations. Most amount of the TSS, oil and grease, organic materials are eliminated in the primary and secondary treatment units. Tertiary/Advanced treatment units are necessary for removal of the remaining portions of the contaminants, heavy metals, nitrogen compounds, and phosphorus. Combination of physical, chemical and biological treatment techniques increase removal efficiency of the contaminants.
This study reports the performance of a new homogenous solar/sodium hypochlorite/iron process in treatment of petroleum refinery wastewater for the aim of water reusing. A pilot-scale solar photo-reactor with capability of automatic rotating against the sun’s surface was employed. Experiments were conducted by following the chemical oxygen demand (COD) and the total organic carbon (TOC) criteria at different times. The optimal operating conditions of 548 mg/L of sodium hypochlorite, 48 mg/L of ferrous salt and pH 3 were found under which COD and TOC removal of, respectively, 78.6% and 69.3% were corresponding after 180 min treatment. The COD removal could easily reach to 88.5% by multiple feeding of the reagents. A significant improvement in the biodegradability was also achieved by raising the BOD5/COD ratio from 0.36 to 0.69. The GC/MS headspace analysis indicated a high degradation level of the most hydrocarbons. Meanwhile, the COD removal was appeared with a pseudo first order kinetic in term of accumulated UV energy. Comparing the performance with the alternative processes including solar Fenton as well as the cost estimates revealed the high preference of the employed process.
Manufacturing and handling of explosives for defence and civilian operations cause widespread environmental contamination. In this study, treatment of wastewater from a HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) production facility was evaluated by advanced oxidation processes, viz. photolysis (UV), photo-peroxidation (UV/H2O2) and photo-Fenton oxidation (UV/Fenton’s reagent). The wastewater sample was highly acidic and was contaminated with HMX, RDX (hexahydro-1,3,5- trinitro-1,3,5-triazine) and nitrated with heavy loads of chemical oxygen demand (COD) and nitrate. During treatment, degradation rate of HMX and RDX and reduction in COD and nitrate levels were monitored. Maximum removal of RDX (99%) and HMX (98%) was achieved under both photo-peroxidation and photo-Fenton oxidation processes in an hour of UV irradiation. Reduction in COD (57.3%) and nitrate content (61.9%) was maximum with photo-Fenton’s treatment system, using Fenton’s reagent (H2O2/FeSO4) in 1:3 ratio. The photo-oxidation process followed pseudo-first-order reaction kinetics. Though the process was efficient in removing high explosives, it was moderate in removing COD and nitrate contents in wastewater.
Dairy industries have shown tremendous growth in size and number in India and other countries of the world. These industries discharge wastewater which is characterized by high chemical oxygen demand, biological oxygen demand, nutrients, and organic and inorganic contents. Such wastewaters, if discharged without proper treatment, severely pollute receiving water bodies. One of the most serious environmental problems is the existence of hazardous and toxic pollutants in wastewaters. Adsorption is considered to be one of the most promising techniques for wastewater treatment over the few decades. Attempts were made in this study to examine the efficiency of Fenton process combined with coagulation for treatment of dairy wastewater. Parameters affecting the Fenton process, such as pH, dosages of Fenton reagents and the contact time, were determined by using jar test experiments 82% of chemical oxygen demand (COD) could be removed at pH 3.0, 1000mg/L H2O2, 2041mg FeSO4 and 50 minutes contact time. The coagulation using ferrous sulfate (FeSO4) was beneficial to improve the Fenton process treated effluent in reducing the flocs settling time, enhancing turbidity and COD removal. The overall turbidity and COD reached 78%, and 85% under selected conditions, respectively. Thus this study might offer an effective way for wastewater treatment of dairy industries.
Advanced oxidation processes are widely applied to removal of persistent toxic substances from wastewater by hydroxyl radicals (·OH), which is generated from hydrogen peroxide (H2O2) decomposition. However, their practical applications have been hampered by many strict conditions, such as iron sludge, rigid pH condition, large doses of hydrogen peroxide and Fe²⁺, etc. Herein, a magnetically recyclable Fe3O4@polydopamine (Fe3O4@PDA) core-shell nanocomposite was fabricated. As an excellent reducing agent, it can convert Fe³⁺ to Fe²⁺. Combined with the coordination of polydopamine and ferric ions, the production of iron sludge is inhibited. The minimum concentration of hydrogen peroxide (0.2 mmol/L and Fe²⁺ (0.18 mmol/L)) is 150-fold and 100-fold lower than that of previous reports, respectively. It also exhibits excellent degradation performance over a wide pH range from 3.0 to 9.0. Even after the tenth recycling, it still achieves over 99% degradation efficiency with the total organic carbon degradation rate of 80%, which is environmentally benign and has a large economic advantage. This discovery paves a way for extensive practical application of advanced oxidation processes, especially in environmental remediation.
In this present paper, the use of TiO2/UV light
process, H2O2/UV light process and Fenton’s
reactions for the treatment of textile waste water has
been reviewed. The main reactions and the operating
parameters viz initial concentration of the target
compounds, amount of oxidation agents and
catalysts, nature of the wastewater affecting the
above-mentioned processes have been enumerated
while several recent applications of wastewater
treatment have been outlined. A comparison study
of different AOPs for removal of colour, COD, MTBE
and phenol has been made. The advantages and
disadvantages of these methods have been brought
out. Some of the future challenges like reduction of
operational cost, adoption of strategies for processes
integration are presented.
In this present paper, the use of TiO2/UV light
process, H2O2/UV light process and Fenton’s
reactions for the treatment of textile waste water has
been reviewed. The main reactions and the operating
parameters viz initial concentration of the target
compounds, amount of oxidation agents and
catalysts, nature of the wastewater affecting the
above-mentioned processes have been enumerated
while several recent applications of wastewater
treatment have been outlined. A comparison study
of different AOPs for removal of colour, COD, MTBE
and phenol has been made. The advantages and
disadvantages of these methods have been brought
out. Some of the future challenges like reduction of
operational cost, adoption of strategies for processes
integration are presented.
Marafiq’s Industrial Wastewater System provides complete solution for delivering exceptional treatment services in a sustainable, cost effective and environment friendly manner to industrial sector in Jubail and Yanbu Industrial Cities. The treatment facilities receive the industrial wastewater generated by industries, convey to the centralized wastewater treatment plant and treat as environmental regulations. The treatment systems consist of wastewater treatment plants (IWTP), conveying network, lift stations, pumping stations and online monitoring equipment. The network of industrial wastewater is available in primary and secondary industrial area of Jubail industrial city. The treated water is used for irrigating the greeneries in Jubail and Yanbu industrial and community areas.
The IWTP at Jubail has a net design capacity of 139,700 m3/d and was constructed in stages, viz., Stage-1 in 1983 (capacity Phase-1 20,000 m3/d, capacity Phase-2: 23,000 m3/d), Stage-2 in 1989 (capacity: 41,700 m3/d), and Stage-3 in 2012 (capacity: 55,000 m3/d). The IWTP at Yanbu has a net design capacity of 72,000 m3/d and was commissioned in phases, viz., Phase-1 in 1984 (capacity: 24,000 m3/d) and Phase-2 in 2014 (capacity: 48,000 m3/d).
The Jubail IWTP Stage-1 consists of a series of asphalt lined ‘earth’ lagoons (ponds), aeration (with nutrient addition) for settlement and sludge treatment. Treatment process was considerably extended in Stage-2 by adding balancing, screening, grit removal, flume in inlet system, primary settlement, oil removal, neutralization, intermediate pressure filtration in pre-treatment and a three-lane conventional activated sludge plant with surface aeration. The treated effluent is further passes through the tertiary pressure filtration and disinfection by chlorination. The Stage-3 is an activated sludge process treatment along with Fenton and granular activated carbon treatment for meeting the environmental regulations for irrigation water quality. This Stage consists of several processes, like screening, grit removal, coagulation, clarification, neutralization, biological treatment, Fenton treatment, activated carbon filters, pressure filters and chlorination.
In this paper, the performance of Jubail IWTP Stage-3 will be assessed, the challenges, mitigations and the lessons learned will be discussed in detail.
A self-made micro-electrolysis-circulatory system with the mixture regime of an upflow bed and reactor was tested for the pretreatment of industrial estate wastewater with a low ratio of biological to chemical oxygen demand (BOD5/COD) at room temperature, 1:1 vol ratio of sponge iron (SFe)/granular activated carbon (GAC), and an intermittent process in aeration and discharge. The system efficiency was evaluated in view of the effects of various processes (hydraulic retention time (HRT), fillers/wastewater ratio (S/L) and aeration). COD reduction of about 51% was obtained for industrial estate wastewater at an S/L ratio of 25%, refluence rate of 16 L/h, HRT of 24 h, and aeration of 60 L/h as the optimal conditions. The considerable change in the calculated BOD5/COD ratio, from 0.07 to 0.49, showed favorable application of the micro-electrolysis-circulatory system for the reductive and oxidative degradation of organic pollutants to enhance wastewater biodegradability. The reusability of the SFe was also investigated after three successive runs. On the basis of the results of Fe leaching, HRT, S/L ratio, scanning electron microscopy observation, and X-ray photoelectron spectroscopic analysis, the corrosion products facilitated by the inherent porosity of SFe played a significant role due to different oxygen conditions in the surface and internal layers. One result from the removal of organic pollutants dominated by the galvanic cell reactions between SFe and GAC was observed, and the integration coagulation in the bulk solution was mainly attributed to the leaching of Fe. The innovative approach described in this study provides a promising and economical technology for pretreatment of industrial wastewater prior to a biological process.
Introduction: About 40% of pesticide production in the world is related to herbicides. Herbicides are one of the major contaminants of aquatic ecosystems. Paraquat (PQ) is a noble, non-selective, and solvent-free herbicide in aqueous solutions. In this study, degradation of paraquat was investigated using the UV/H2O2 process.
Methods: In the present study, variables, including initial concentration of toxin, contact time, pH, and H2O2 concentration on paraquat removal in a laboratory scale were investigated. The concentration of the residual paraquat was determined using HPLC. The amount of mineralization under optimal conditions was measured by measuring the amount of TOC removal according to the standard method 5310- B.
Results: The optimum removal efficiency of PQ by UV/H2O2 process was 87.75% with H2O2 concentration of 33 mmol/L, pH of 5, initial PQ concentration of 25 mg/L, and reaction time of 120 minutes. Moreover, 77.29% of the Total Organic Carbon (TOC) was removed under similar conditions. In addition, the data was found to follow the first-order kinetics.
Conclusions: Considering the growing use of UV radiation in water treatment processes and the considerable efficiency of UV/ H2O2 process in removing PQ, this method can be proposed for the elimination of PQ after performing cost-benefit analyses.
This research showed that according to purification goals and standards for wastewater treatment, UV/ H2O2 process can be used as a past or final treatment.
The destruction of pesticide active ingredients (AI) and commercial formulations in acidic aqueous solution with the catalytic photo-Fenton, Fe(III)/H2O2/UV, advanced oxidation process has been studied. The AI are alachlor, aldicarb, atrazine, azinphos-methyl, captan, carbofuran, dicamba, disulfoton, glyphosate, malathion, methoxylchlor, metolachlor, picloram and simazine. Complete loss of pure AI occurred in most cases in < 30 min under the following conditions: 5.0 x 10(-5) M Fe(III), 1.0 x 10(-2) M H2O2, T = 25.0 degrees C, pH 2.8 and 1.2 x 10(19) quanta l(-1) s(-1) with fluorescent blacklight UV irradiation (300-400 nm). Considerable mineralization over 120 min occurred in most cases as evidenced by the appearance of inorganic ions and the decline in total organic carbon (TOC) of the solution. Intermediate products such as formate, acetate and oxalate appeared in early stages of degradation in some cases. Observed rate constants calculated from initial rates varied by a factor of <similar to 3. The commercial products, Furadan (AI, carbofuran), Lasso 4EC (AI, alachlor) and Lasso Microtech (AI, alachlor) were also tested. The "inert ingredients" (adjuvants) present in these products had no effect (Furadan), a slight effect (Lasso 4EC), or a strong effect (Lasso Microtech) on the rate of degradation of the AI. Lasso Microtech, in which the AI is micro-encapsulated in a polymeric shell wall microsphere, required slightly elevated temperatures to effect removal of alachlor in a timely manner. The results show that many pesticides and their commercial formulations in dilute aqueous solution are amenable to photo-Fenton treatment.
The effect of chlorine content of chlorinated phenols on their oxidation kinetics by Fenton's reagent was evaluated through different kinetic studies. First, elementary oxidation rate constants between hydroxyl radicals and 2,4-DCP, 2,4,6-TCP as determined in this study are 7.2∗109 M−1s−1 and 6.3∗109 M−1s−1 respectively.The relative ratios between the rate constants of 2-CP and 2,4,6-TCP referred to the rate constant of 2,4-DCP indicates that the reactivity of chorophenols decreases with increasing substitution of chlorine on the aromatic ring. Second, the pseudo-first order oxidation kinetic constants at overdosed H2O2 and Fe2+ were proportional to the number of unsubstituted positions, while no correlation between dechlorination constants and the number of unoccupied sites on the aromatic ring was found.Third, dechlorination kinetic model as a function of 11202, Fe, and chlorophenol concentration was developed. At constant 11202 concentration of 5 ∗ 10−3 M, the observed dechlorination rate constants for 2-MCP, 2,4-DCP, and 2,4,6-TCP are 1.16∗107 M−1s−1, 2.28∗ 107 M−1s−1 and 4.36∗108 M−1s−1, respectively. All of these results demonstrated that the oxidation rate constants decrease with increasing content of chlorine. In addition, the initial dechlorination rates do not change significantly for all the chlorinated phenols studied at constant 11202 and Fee* concentration, which suggests that the limiting step in Fenton chemistry is the generation of hydroxyl radicals through H2O2 and Fe2+.
Photo-Fenton process was explored as photochemical pre-treatment to improve the biodegradability of a wastewater coming from a textile industry located in the south of France, which was characterized as very biorecalcitrant by means of Zahn–Wellens biodegradability test. The effect of H2O2, Fe(III) and temperature on the photo-mineralization processes have been studied and the optimal conditions were found. Experiments were made to obtain information concerning the evolution of the biodegradability of the treated effluent after 40 and 70% of photo-mineralization. The photo-treated effluent is not biocompatible and its complete mineralization cannot be performed by biological means. UV–VIS and high-performance liquid chromatography (HPLC) analyses show that aromatic intermediates remain in the effluent after the photo-treatment, which have been identified as the principal reason of the biorecalcitrance.
The oxidation of two wastewaters collected from distillery and tomato processing plants with UV radiation (254 nm) alone and combined with hydrogen peroxide has been investigated. Distillery wastewaters are refractory to UV radiation but the presence of hydrogen peroxide leads to different COD reductions which indicates that the process is mainly due to the action of radicals. Tomato wastewaters, on the other hand, show a higher reactivity even with UV radiation alone. The quantum yield for tomato wastewaters with an initial COD of 930 mg O2l−1 was found to be 0.7 mol O2 photon−1 and decreased with reaction time. The combined effect of UV radiation and hydrogen peroxide at a 0.01 M concentration on tomato wastewaters leads to about 25% COD reduction while TOC was unchanged. The contribution of radical reactions in this process was higher than 60%.
Ethylene glycol loss rate constants of 1.0±0.40 h−1 were achieved in photo Fenton systems containing concentrations of 1000 mg/l ethylene glycol. Ethylene glycol was converted to formic acid resulting in a loss of calculated chemical oxygen demand. Iron was not catalytic in the system which may be due to the formation of ferric oxalate complexes. The system was inhibited by elevated concentrations of sulfate and a phosphate buffer solution. The optimal pH was 3.0, with significant decreases in the degradation rates below 2.8 and above 3.2. Increased TOC loss was noted in similar UV/H2O2 systems indicating a potential for increased mineralization in optimized photo Fenton systems with longer residence times.
Advanced oxidation processes (O3/UV and O3/H2O2) have been adopted for the treatment of mineral oil-contaminated wastewater. All the experimental runs have been performed in a 0.2-l semicontinuous reactor (equipped with a nominal power of 17 W UV lamp for illuminated experiments). The results of this investigation show that the system O3/UV is capable of achieving high levels of purity ranging from 80 to 90% abatement of the inlet COD with reaction times not longer than 30 min. Modeling of the reacting system has been also attempted to evaluate the rate parameters involved in some reaction steps. A preliminary estimation of the costs of adopted AOP techniques is provided.
Fenton reagent has been used to test the degradation of different organic compounds (formic acid, phenol, 4-chlorophenol, 2,4-dichlorophenol and nitrobenzene) in aqueous solution. A stoichiometric coefficient for the Fenton reaction was found to be 0.5 mol of organic compound/mol of hydrogen peroxide, except for the formic acid where a value of approximately one was obtained (due to the direct formation of carbon dioxide). The treatment eliminates the toxic substances and increases the biodegradability of the treated water (measured as the ratio BOD5/COD). Biodegradability is attained when the initial compound is removed.
Oxidation by Fenton-like reactions is proven and economically feasible process for destruction of a variety of hazardous pollutants in wastewater. We report herein the oxidation of methylene blue, a basic dye of thiazine series using a Fenton-like reaction at normal laboratory temperature and at atmospheric pressure. The effects of different parameters like the initial concentrations of dye, Fe2+, and H2O2, pH of the solution, reaction temperature, and added electrolytes on the oxidation of the dye present in dilute aqueous solution in the concentration range (3.13-9.39)x10(-5)mol dm(-3) (10-30 mg l(-1)) have been assessed. The results indicate that the dye can be most effectively oxidized in aqueous solution at dye:Fe(2+):H2O2 molar ratio of 1:1.15:14.1. More than 98% removal of the dye could be achieved in 1h in the pH range 2.2-2.6 at 299 K which corresponds to about 81% reduction of the initial COD. The results will be useful for designing the treatment systems of various dye-containing wastewaters.
The pre-oxidation of an extremely polluted pharmaceutical wastewater (chemical oxygen demand (COD) value of 362,000mg/l) using the Fenton's reagent has been systematically studied using an experimental design technique. The parameters influencing the COD removal of the wastewater, namely temperature, ferrous ion and hydrogen peroxide concentrations have been optimized to achieve a COD global reduction of 56.4%. The total range of the proposed experimental design, however, could not be tested because under some conditions (hydrogen peroxide concentration over 5M) the Fenton's reaction became violent and could not be controlled, probably due to the high exothermic effect associated with COD oxidation. For the tested conditions, the optimal values of hydrogen peroxide and ferrous ion concentration were 3 and 0.3M, respectively, whereas temperature only showed a mild positive effect on COD removal. In addition, during the first 10min of Fenton's reaction, more than 90% of the total COD removal can be achieved.Fenton's reaction has proved to be a feasible technique for the pre-oxidation of the wastewater under study, and can be considered a suitable pre-treatment for this type of wastewaters.
Multivariate experimental design was applied to the treatment of a cellulose conventional bleaching effluent in order to evaluate the use of the Fenton reagent under solar light irradiation. The effluent was characterised by the general parameters total organic carbon (TOC), chemical oxygen demand and color, and it was analysed for chlorinated low molecular weight compounds using GC-MS. The main parameters that govern the complex reactive system: Fe(II) and H(2)O(2) initial concentration, and temperature were simultaneously studied. Factorial experimental design allowed to assign the weight of each variable in the TOC removal after 15 min of reaction. Temperature had an important effect in the organic matter degradation, especially when the ratio of Fenton reagents was not properly chosen. Fenton reagent under solar irradiation proved to be highly effective for these types of wastewaters. A 90% TOC reduction was achieved in only 15 min of treatment. In addition, the GC-MS analysis showed the elimination of the chlorinated organic compounds initially detected in the studied bleaching effluents.
An environmental study using life cycle assessment (LCA) has been applied to three bench-scale wastewater treatments for Cibacron Red FN-R hetero-bireactive dye removal: artificial light photo-Fenton process, solar driven photo-Fenton process and artificial light photo-Fenton process coupled to a biological treatment. The study is focused on electricity and chemicals consumption, transports and atmosphere and water emissions generated by the different processes involved. Results show that the artificial light photo-Fenton process is the worst treatment in terms of environmental impact. On the other hand, both solar driven and coupled to biological photo-Fenton processes reduce significantly the environmental damage, although none can be identified as the best in all impact categories. The major environmental impact is attributed to the H2O2 consumption and to the electrical energy consumption to run the UVA lamp. An economic analysis of the different photo-Fenton processes has also been performed and the results are discussed together with those obtained from the environmental assessment.