Synthetic Industrial Wastewater Research Articles

Improvement of ferrioxalate assisted Fenton and photo-Fenton processes for paracetamol degradation by hydrogen peroxide dosage.

This work aimed to investigate the impact of hydrogen peroxide (HP) punctual dosage on paracetamol (PCT) degradation, through Fenton and photo-Fenton processes under near-neutral pH conditions, using ferrioxalate and artificial sunlight. The assays were performed using a D-optimal experimental design, to statistically evaluate the influence of radiation (ON or OFF), HP concentration (94.5-756mg L-1), and HP dosage (YES or NO), on PCT conversion. The optimal conditions determined from the study were: HP = 378mg L-1, DOS = YES, and RAD = ON, achieving a predicted PCT conversion of 99.68% in 180min. This result obtained from the model was very close to the experimental one (98.80%). It was verified that HP dosage positively influenced the iron catalytic cycle since higher Fe2+ concentrations were reached at shorter reaction times, accelerating not only PCT conversion but also its by-products hydroquinone and 1,4-benzoquinone, leading to better performances of Fenton and photo-Fenton reactions. Under optimal conditions and employing real water matrices (an artificial matrix with inorganic anions, a real groundwater sample, and a synthetic industrial wastewater), HP dosage demonstrated the ability to mitigate the negative effects caused by the content of different ions and other organic compounds and significantly improve HP consumption in challenging wastewater conditions.

Environmentally friendly TDS removal from waste water by electrochemical ion exchange batch-type recirculation (EIR) technique

The increasing prevalence of total dissolved solids (TDS), Cl−, SO42−, total suspended solids (TSS), BOD and COD in industrial effluent necessitates pioneering electrochemical approaches for their efficient removal.

Performance of the UASB reactor during wastewater treatment and the effect of the biogas bubbles on its hydrodynamics

ABSTRACT A lab-scale Upflow Anaerobic Sludge Blanket (UASB) reactor was used as a model for evaluating synthetic and complex industrial wastewater treatment, using a solar heater to control temperature. Also, hydrodynamics was assessed using the Computational Fluid Dynamics (CFD) method. Initially, the UASB reactor was operated with synthetic wastewater at Hydraulic Retention Time (HRT) of 24 h in 20 ± 2 °C and 30 ± 2 °C to measure the biogas bubbles production for CFD study. COD removal efficiencies of 85 ± 3% and 95 ± 3%, respectively, with production of 27 and 39 ml CH4/h, correspondingly, were observed. After that, the reactor was fed with complex industrial wastewater. It was evaluated at 24 h in both temperatures. At 30 °C, low COD removal efficiency was observed, being 48 ± 13%, with methane production of 20 ± 3 ml CH4/h. The plug flow pattern was observed in the CFD modelling at HRT of 24 h and 20 °C without considering biogas bubbles interaction. Similar hydrodynamic behaviour was observed at HRT of 24 h and 30 °C. Nonetheless, when biogas bubbles were considered in the CFD modelling, hydrodynamics significantly changed, passing from a plug flow to a complete mix flow pattern.

Binary Adsorption of Phenol and 2-Chlorophenol on Chitosan Derived from Pink Shrimp Shell

The binary adsorption of phenol and 2-chlorophenol in a synthetic industrial wastewater was investigated using extracted optimized chitosan from pink shrimp shell wastes as adsorbent. The effects of operational parameters on the binary adsorption system were studied. The equilibrium adsorption data for the binary system were analyzed using extended Langmuir, extended Sips, extended Redlich-Peterson and Fritz-Schlüender adsorption isotherms. The Fritz-Schlüender isotherm fitted the adsorption data excellently wherein the maximum adsorption capacities for phenol and 2-chlorophenol were obtained as 6.7431 and 14.7493 mg/g respectively for the optimized chitosan at pH=4, adsorbent dose of 1 g, initial concentration of phenol and 2-chlorophenol = 25-250 mg/L, contact time of 120 min, agitation speed of 150 rpm, particle size of 250 microns and temperature of (28 ± 2)°C. The kinetic modelling of the phenol-2-chlorophenol adsorption system showed that pseudo second-order kinetic model gave the best fit amongst the investigated kinetic models. The simultaneous adsorption of phenol and 2-chlorophenol on the prepared adsorbent was chemisorption and film-diffusion controlled. The thermodynamic parameters of the binary adsorption system indicated that the simultaneous adsorption of phenol and 2-chlorophenol on the extracted optimized chitosan was relatively favourable, non-spontaneous, endogenic and exothermic with changes in Gibb’s free energy, G ∆ , positive, entropy, S ∆ , approximately zero (though negative), and enthalpy, H∆, negative.

Advanced oxidation process for the removal of dyes from synthetic industrial wastewaters

Advanced oxidation process for the removal of dyes from synthetic industrial wastewaters

Corrigendum to "Performance evaluation of multi-walled carbon nanotubes for decolorization of synthetic industrial wastewater: equilibrium, kinetics, and thermodynamics" published in vol. 188, June 2020, pp. 194-201 [doi:10.5004/dwt.2020.25368

Corrigendum to "Performance evaluation of multi-walled carbon nanotubes for decolorization of synthetic industrial wastewater: equilibrium, kinetics, and thermodynamics" published in vol. 188, June 2020, pp. 194-201 [doi:10.5004/dwt.2020.25368

Model sorption of industrial wastewater containing Cu2+, Cd2+, and Pb2+ using individual and mixed rice husk biochar

Few studies have used biochar mixtures to remove potentially toxic elements from industrial wastewater. The present batch studies compare the adsorption of Cu 2 + , Cd 2 + , and Pb 2 + by single and mixed sorbents using rice husk feedstock (RH), rice husk biochar (RHB), ethylene-diamine-tetra-acetic acid-modified biochar (EDTA-RHB), and a mixture (MB) of these biosorbents. Metal sorption studies were carried out by varying the adsorbents, metal ion concentrations, contact time, and solution pH in a synthetic industrial wastewater. In all experiments, RHB, EDTA-RHB, and MB removed up to 98% of the metal ions within 60 min at pH 4. Kinetic studies showed that first- and second-order models gave the best fit for MB; whereas, the Freundlich model gave the best fit for the isotherm data. Results indicate that MB and EDTA-RHB treatments were more effective for adsorbing the studied heavy metals than RH or RHB. Such biosorbents could be useful in the treatment of co-existing potentially toxic elements from wastewater. • Individual and mixed biosorbents efficiently removed the heavy metals. • Double Gompertz model best fitted to the metal removal, vs. logistic, 2x logistic, or Gompertz. • Adsorption by mixed adsorbents best fitted with Freundlich compared to Langmuir model. • Mixed adsorbents had higher adsorption of Cu 2+ , Cd 2+ , and Pb 2+ in a mixture solution.

Removal of Cr (III) from industrial wastewater using coconut shell carbon and limestone as adsorbent

Agricultural waste materials gained attention among researchers to study the effectiveness of adsorbent media in heavy metal treatment. In this study, application of coconut shell carbon and limestone as modified adsorbent was used to remove Cr (III) from industrial wastewater. Synthetic industrial wastewater sample containing 2 mg/L of Cr (III) was prepared using distilled water and standard solution of Cr (III). Batch adsorption study was conducted to determine the effect of varied contact time (0 to 120 minutes) and pH (pH3 to pH7). The result shows that at 60 minutes of contact hour, the removal of Cr (III) from the synthetic industrial wastewater is about 98% with optimum adsorption capacity is 0.000019 mg/g at 250 rpm of agitation speed in pH5 as optimum pH. The kinetic data obtained specified that the data follow closely the pseudo-second-order. Thus, this indicates that mixing coconut shell carbon and limestone as a modified adsorbent has a potential in reducing Cr (III) concentration in industrial wastewater.

Mercury, Arsenic and Lead Removal by Air Gap Membrane Distillation: Experimental Study

Synthetic industrial wastewater samples containing mercury (Hg), arsenic (As), and lead (Pb) ions in various concentrations were prepared and treated by air gap membrane distillation (AGMD), a promising method for heavy metals removal. Three different membrane pore sizes (0.2, 0.45, and 1 μm) which are commercially available (TF200, TF450, and TF1000) were tested to assess their effectiveness in combination with various heavy metal concentrations and operating parameters (flow rate 1–5 L/min, feed temperature 40–70 °C, and pH 2–11). The results indicated that a high removal efficiency of the heavy metals was achieved by AGMD. TF200 and TF450 showed excellent membrane removal efficiency, which was above 96% for heavy metal ions in a wide range of concentrations. In addition, there was no significant influence of the pH value on the metal removal efficiency. Energy consumption was monitored at different membrane pore sizes and was found to be almost independent of membrane pore size and metal type.

Preparation of a thin-film nanocomposite forward osmosis membrane for the removal of organic micro-pollutants from aqueous solutions

ABSTRACT In this study, a thin-film nanocomposite forward osmosis (TFN FO) membrane was synthesized. The properties and structures of membranes were evaluated for the removal of three organic micro-pollutants from synthetic and real industrial wastewater samples. Laboratory scale fabrication thin-film nanocomposite forward osmosis (FO) membranes composed of a support layer and an active layer. The former was constructed by adding different weight ratios of polyethylene glycol 400 (PEG-400) (0–8 wt.%), polysulfone (PSf), and 1-methyl, 2-pyrrolidone via the phase inversion process, while the latter was synthesized by the incorporation of different weight ratios of graphene oxide (GO) (0–0.012 wt.%), M-phenylenediamine, and 1, 3, 5-benzene trichloride into polyamide layer through the interfacial polymerization reaction. In comparison with thin-film composite (TFC) membranes, the TFN membranes revealed higher hydrophilicity, porosity, water permeability, water flux and salt rejection and lower internal concentration polarization (ICP), reverse salt flux and specific reverse salt flux. The TFN membrane containing 0.008% GO in the active layer and 4% PEG 400 in the support layer exhibited maximum water flux (34.3 LMH) and rejection rate of benzene, phenol and toluene (97%, 84%, and 91%, respectively). The results revealed that the TFN-FO membranes possess a promising potential to improve the water flux and wastewater treatment.

Performance evaluation of multi-walled carbon nanotubes for decolorization of synthetic industrial wastewater: equilibrium, kinetics, and thermodynamics

Performance evaluation of multi-walled carbon nanotubes for decolorization of synthetic industrial wastewater: equilibrium, kinetics, and thermodynamics

A comparative long-term operation using up-flow anaerobic sludge blanket (UASB) and anaerobic membrane bioreactor (AnMBR) for the upgrading of anaerobic treatment of N, N-dimethylformamide-containing wastewater

Synthetic industrial wastewater containing approximately 2000 mg/L N, N-dimethylformamide (DMF) was treated using a lab-scale anaerobic sludge blanket (UASB) and an anaerobic membrane bioreactor (AnMBR) in this study. The inoculum consisted of two sources of sludge: Co-culture of anaerobic digested sludge (ADS) with DMF-hydrolyzing activated sludge (DAS) for the AnMBR, and co-culture of anaerobic granular sludge (AGS) with DAS for the UASB. Effective DMF methanogenic degradation of nearly 100% removal was achieved in both reactors on the first day. Both reactors obtained excellent DMF removal efficiency and high methane production under a low organic loading rate (OLR) of around 3–4 g COD/L/d. However, excessive elevation of OLR significantly limited DMF hydrolysis. When OLR exceeded 6 g COD/L/d, the removal efficiency and methane production in both reactors dramatically dropped. Despite their different forms and shapes, the ADS and AGS both provide methanogens which are responsible for methanogenesis. The UASB tolerated a higher OLR while the AnMBR was limited by membrane fouling due to the increased sludge concentration. However, the AnMBR obtained high-quality effluent without suspended solid. Whether DMF can be effectively degraded depends on DAS, in which abundant DMF-hydrolyzing bacteria (DHB) provide sufficient quantities of the hydrolytic enzyme for effective hydrolysis of DMF. However, these DHB were facultative and were also identified as denitrifying bacteria which require nitrate as the electron acceptor or otherwise survive under the aerobic condition. They gradually decayed rather than proliferated and were outcompeted by methanogens. Therefore, it is conceivable that a slight dosage of nitrate would enrich the abundance of DHB in both the UASB and the AnMBR, and provide a sufficient quantity of enzymes for the DMF hydrolysis. The cultivation of the anaerobic DMF-degrading granular sludge using the UASB is considered an upgraded solution to the effective treatment of DMF-containing wastewater.

Nutrient removal from high strength nitrate containing industrial wastewater using Chlorella sp. strain ACUF_802

the research aim of this study was to characterize an isolated native strain of Chlorella sp. ACUF_802, well adapted to a high nitrate concentration environment and to investigate its potential to nitrate and phosphate removal from industrial wastewaters with the minimal addition of chemical reagents and energy. The isolated strain was identified and evaluated for its capability to support biomass growth and nutrient removal from synthetic wastewater in batch tests using different concentrations of carbon and nitrogen, different carbon sources and N:P ratios. The strain was isolated via the plating method from the settler of a pilot scale moving bed biofilm reactor performing a nitrification process. The strain was identified using molecular analysis with rDNA primers. Using sodium bicarbonate as carbon source, the batch productivity (71.43 mg L−1 day−1) of the strain Chlorella sp. ACUF_802 was calculated with a logistic model and compared to the values reported in the literature. Assays on the effect of the N:P ratio indicated that the productivity was increased 36% when the N:P ratio was close to 1 (111.96 mg L−1 day−1), but for a complete phosphorus removal a 5:1 N:P ratio with nitrate concentrations ≤125 mg∙L−1 is recommended. The isolated microalgae strain Chlorella sp. ACUF_802 showed versatility to grow in the synthetic industrial wastewaters tested and can be considered as an appropriate organism for nitrogen removal from industrial wastewaters in the presence of an organic or inorganic carbon source.

Batch Adsorption Study of Methylene Blue in Aqueous Solution using Activated Carbons from Rice Husk and Coconut Shell

The removal efficiency of activated carbons prepared from rice husk and coconut shell in the adsorption of methylene blue (azo dye) from the synthetic industrial wastewater was investigated in a batch system. Rice husk and coconut shell were both processed into activated carbon by carbonizing at 600 oC and activated with 3.0 M H3PO4 at 80 oC for 3h. Synthetic solutions of methylene blue were prepared and the adsorption process was carried out by varying initial, methylene blue concentration, adsorbent dosage, and contact. The results showed that higher values of adsorbent dosage and contact time favored the adsorption of methylene blue from the simulated waste water. Activated carbon from coconut shell proved a better adsorbent compared to the activated carbon obtained from rice husk as coconut shell has the highest percentage removal for methylene blue.

Calcium ion- and rhamnolipid-mediated deposition of soluble matters on biocarriers

Start-up of biofilm process initiated by the deposition of soluble matters on biocarriers is a very important yet time-consuming procedure. However, rapid start-up methods especially in the enhancement of soluble matters deposition have been rarely addressed. In this study, a quartz crystal microbalance with dissipation monitoring (QCM-D) was applied to investigate the influences of calcium ion and rhamnolipid (RL) on the deposition of soluble matters from real and synthetic industrial wastewaters with different configurations of organics (bovine serum albumin and sodium alginate) and ionic strength on the model biocarriers polystyrene and polyamide. Results showed that deposition was effectively promoted by the addition of Ca2+ and along with the increase in Ca2+ content. However, RL enhanced the deposition effectively only in hyperhaline wastewater through breaking hydration repulsion and decreased the deposition in low-salinity wastewater, and its influence to the deposited layer property exhibited characteristics of negative feedback. The combined use of Ca2+ and RL had a better enhancement effect than that of separate use and the mechanism involved can not be soundly explained only by Derjaguin−Landau−Verwey−Overbeek (DLVO) theory. The strategy of mediating the deposition of soluble matters on different biocarriers by adding Ca2+ and RL has important implications for regulating biofilm formation to accelerate the start-up process in attached-growth bioreactors.

The startup performance and microbial distribution of an anaerobic baffled reactor (ABR) treating medium-strength synthetic industrial wastewater

ABSTRACTIn this study, an anaerobic baffled reactor (ABR) with seven chambers was applied to treat medium-strength synthetic industrial wastewater (MSIW). The performance of startup and shock test on treating MSIW was investigated. During the acclimation process, the chemical oxygen demand (COD) of MSIW gradually increased from 0 to 2,000 mg L−1, and the COD removal finally reached 90%. At shock test, the feeding COD concentration increased by one-fifth and the reactor adapted very well with a COD removal of 82%. In a stable state, Comamonas, Smithella, Syntrophomonas and Pseudomonas were the main populations of bacteria, while the predominant methanogen was Methanobacterium. The results of chemical and microbiological analysis indicated the significant advantages of ABR, including buffering shocks, separating stages with matching microorganisms and promoting syntrophism. Meanwhile, the strategies for acclimation and operation were of great importance. Further work can test reactor performance in the treatment of actual industrial wastewater.

Identification of hotspots for NO and N2O production and consumption in counter- and co-diffusion biofilms for simultaneous nitrification and denitrification

A membrane-aerated biofilm reactor (MABR) provides a counter-current substrate diffusion geometry in which oxygen is supplied from a gas-permeable membrane on which a biofilm is grown. This study hypothesized that an MABR would mitigate NO and N2O emissions compared with those from a conventional biofilm reactor (CBR). Two laboratory-scale reactors, representing an MABR and CBR, were operated by feeding synthetic industrial wastewater. The surficial nitrogen removal rate for the MABR [4.51±0.52g-N/(m2day)] was higher than that for the CBR [3.56±0.81g-N/(m2day)] (p<0.05). The abundance of β-proteobacterial ammonia-oxidizing bacteria in the MABR biofilm aerobic zone was high. The NO and N2O concentrations at the biofilm–liquid interface in the MABR were 0.0066±0.0014 and 0.01±0.0009mg-N/L, respectively, two and 28 times lower than those in the CBR. The NO and N2O production hotspots were closely located in the MABR aerobic zone.

Development of a high-rate submerged anaerobic membrane bioreactor

ABSTRACTTypically, anaerobic membrane bioreactors are operated at an organic loading rate (OLR) less than 10 kg chemical oxygen demand (COD)/m3 d. This paper discusses the development and performance of a high-rate submerged anaerobic membrane bioreactor (SAnMBR) for a high-strength synthetic industrial wastewater treatment. An OLR as high as 41 kg COD/m3 d was achieved with excellent COD removal efficiency (>99%). The membrane was operated at constant fluxes (9.4–9.9 ± 0.5 L/m2 h) and the change in trans-membrane pressure (TMP) was monitored to characterize the membrane performance. The results showed a low TMP (<5 kPa) under steady-state operation with only biogas sparging and relaxation as control strategy for over 300 days, implying no significant fouling was developed. Inorganic fouling was the dominant fouling mechanism occurred at the end of the study. The results suggest that the newly developed SAnMBR configuration can treat high-strength wastewater at lower capital expenditure while still providing superior effluent quality for water reuse or system closure.

Removal of Ni(II), Pb(II), and Cu(II) from Industrial Wastewater by Using NF Membrane

This article reviews the technical applicability of nanofiltration membrane process for the removal of nickel, lead, and copper ions from industrial wastewater.&#x0D; Synthetic industrial wastewater samples containing Ni(II), Pb(II), and Cu(II) ions at various concentrations (50, 100, 150 and 200 ppm), under different pressures (1, 2, 3 and 4 bar), temperatures (10, 20, 30 and 40 oC), pH (2, 3, 4, 5 and 5.5), and flow rates (1, 2, 3 and 4 L/hr), were prepared and subjected treated by NF systems in the laboratory. Suitable NF membrane was chosen after testing a number of NF membranes (University of Technology-Baghdad), in terms of production and removal. NF system was capable of removing more than (85%, 78%, and 66% for Ni(II), Pb(II), and Cu(II) ions respectively). The permeate flux for all H.M ions for were ranges between (14 to 62 L/m2.hr). The results showed that the NF membrane was capable of treating industrial wastewater with any concentration of heavy metals ions and reducing the ion concentration to about (15, 22, and 34 ppm) for Ni(II), Pb(II), and Cu(II) ions respectively. The low level of the heavy metals concentration in the permeate implies that water with good quality could be reclaimed for further reuse. The NF membrane is characterized by efficiently H.M. ions removal medium with high productivity and very low pressure up to 1 bar, which means very little cost for NF system.

Removal of Nitrogen Compounds from Industrial Wastewater Using Sequencing Batch Reactor: The Effects of React Time

This study was performed to optimise the react time (RT) and study its effects on the removal rates of nitrogen compounds in a sequencing batch reactor (SBR) treating synthetic industrial wastewater. The results showed that increasing the RT from 4 h to 10, 16 and 22 h significantly improved the nitrogen compounds’ removal efficiency, it was increased from 69.5% to 95%, 75.7 to 97% and from 54.2 to 80.1% for NH3-N, NO3-N and NO2-N respectively. The results obtained from this study showed that the RT of 22 h was the optimum for nitrogen compounds removal efficiency.