Biotreated Effluent Research Articles

Using UV/peracetic acid as pretreatment for subsequent bio-treatment of antibiotic-containing wastewater treatment: Mitigating microbial inhibition and antibiotic resistance genes proliferation

UV/peracetic acid (PAA) treatment presents a promising approach for antibiotic removal, but its effects on microbial community and proliferation of antibiotic resistance genes (ARGs) during the subsequent bio-treatment remain unclear. Thus, we evaluated the effects of the UV/PAA on tetracycline (TTC) degradation, followed by introduction of the treated wastewater into the bio-treatment system to monitor changes in ARG expression and biodegradability. Results demonstrated effective TTC elimination by the UV/PAA system, with carbon-centered radicals playing a significant role. Crucially, the UV/PAA system not only eliminated antibacterial activity but also inhibited potential ARG host growth, thereby minimizing the emergence and dissemination of ARGs during subsequent bio-treatment. Additionally, the UV/PAA system efficiently removed multi-antibiotic resistant bacteria and ARGs from the bio-treatment effluent, preventing ARGs from being released into the environment. Hence, we propose a multi-barrier strategy for treating antibiotic-containing wastewater, integrating UV/PAA pre-treatment and post-disinfection with bio-treatment. The inhibition of ARGs transmission by the integrated system was verified through actual soil testing, confirming its effectiveness in preventing ARGs dissemination in the surrounding natural ecosystem. Overall, the UV/PAA treatment system offers a promising solution for tackling ARGs challenges by controlling ARGs proliferation at the source and minimizing their release at the end of the treatment process.

Hydrogen peroxide and peroxymonosulfate intensifying Fe−doped NiC−Al2O3−framework−based catalytic ozonation for advanced treatment of landfill leachate: Performance and mechanisms

The biotreated effluent of landfill leachate still contains numerous refractory organic contaminants, which poses potential threats to human health and ecosystems. Influenced by landfill ages and other factors, the concentration of organic matter varies. Heterogeneous catalytic ozonation (HCO) is a promising technology for advanced wastewater treatment. Aiming to achieve the up-to-standard discharge of low-concentration landfill leachate (COD ≈ 108 mg·L-1) and improve the biodegradability of high-concentration landfill leachate (COD ≈ 1720 mg·L-1), the active component Fe was incorporated into a firm Ni-induced C-Al2O3-framework (NiCAF) composite support to synthesize a Fe-NiCAF catalyst for efficient catalytic ozonation. When the Fe-NiCAF dosage was 4 g·L-1, the gas flow rate was 0.5 L·min-1, and the ozone concentration was 20.0 mg·L-1, the COD of low-concentration landfill leachate effluent decreased to 43 mg·L-1, and the COD removal rate constant of low-concentration landfill leachate was 154% higher than that of pure ozone. For high-concentration landfill leachate with the BOD5/COD of 0.058, the COD removal efficiency in Fe-NiCAF/O3 increased from 39% to 57% compared with ozonation, and the effluent BOD5/COD increased to 0.282. Furthermore, the addition of hydrogen peroxide (H2O2) and peroxymonosulfate (PMS) can further enhance the treatment performance of Fe-NiCAF/O3 process and different strengthening mechanisms were revealed. The results indicated that surface hydroxyls on the Fe-NiCAF catalyst surface were the main catalytic sites for ozone, and hydroxyl radical (•OH) and singlet oxygen (1O2) were identified as the main reactive oxygen species for the removal of organics in landfill leachate. Adding H2O2 can promote the generation of •OH for nonselective degradation of various organics, while PMS mainly enhanced the production of 1O2 to decompose macromolecular humus. This work highlighted an efficient Fe-NiCAF ozone catalyst and an innovative peroxide intensified HCO strategy for the advanced treatment of landfill leachate.

Submerged microfiltration membrane and activated carbon processes for recalcitrant compounds removal in oil refinery effluent as electrodialysis pre-treatment.

The combination of suspended activated carbon (AC) and submerged microfiltration (SMF) processes was applied to polish a biotreated effluent generated in a refinery industry. Preliminary results indicated that Norit 1240 W AC was more suitable than Carbomafra AC brand for total organic carbon (TOC) removal due to the highest Freundlich adsorption constant value (1.97 ± 0.42 and 0.96 ± 0.23 (mg/g)(L/mg)1/n, respectively), thus the first one was used in the combined system. Among all particle sizes of AC tested (0.041-1.01 mm), AC/SMF system was better performed, according to permeation flux, when applying granular AC instead of the powder one. On the other hand, the best response regarding TOC removal and absorbance at 254 nm (ABS254 nm) reduction were observed when applying powder AC (89% and 97%, respectively). Statistical analysis with two-sample T-test (p-value <0.05) endorsed the need of both air purge (20 L/h) and backwash strategies (8 min of permeation and 10 seconds of backwash) to diminish fouling occurrence in the SMF system. Finally, it was found that 2 g/L of Norit 1240 W PAC (0.041 mm particle size) condition fitted the effluent to further electrodialysis reversal (EDR) process (3.4 mg/L TOC) with consistent normalized permeate flux after 5 h of permeation (0.76 ± 0.1 J/J0).

Biotreatment of Effluent from Cassava Processing Using Powdered Seeds of Moringa oleifera

The world is facing increasingly more severe water security issues. It has, therefore, become imperative to develop sustainable, eco-friendly water management and recycling techniques. This study assessed the capacity of powdered seeds of Moringa oleifera to improve water quality of effluent from two (2) cassava processing plants in Umudike, Nigeria by measuring the variations in specific physicochemical and microbiological parameters of the samples. The biodegradability indices of the wastewater samples were determined as 0.513 and 0.507 for Plants 1 and 2 respectively indicating samples that were fairly biodegradable and treatable biologically. At the end of the 7-day study, turbidity reduced by 59.6% – 63.2% while chemical oxygen demand (COD), biochemical oxygen demand (BOD) and total organic carbon values dropped by 66.6% – 74.1%, 86.7% – 88.2% and 67.0% – 72.6% respectively. Correlation analysis showed a strong positive correlation between BO₅ and COD for both Plants 1 and 2. The total heterotrophic and coliform bacteria were completely removed by around day 5 of the study. The observed bacterial isolates in the effluent at onset were Escherichia coli, Bacillus sp., Klebsiella sp., Salmonella sp., Streptococcus faecalis, Shigella sp. and Aerobacter aerogenes. This study confirms the efficiency of powdered seeds of M. oleifera in biotreatment of wastewater from cassava processing plants.

Advanced treatment of bio-treated effluents of printing and dyeing wastewater using sub-micron CaO2/Fe2+ oxidation

The sub-micron CaO2/Fe2+ oxidation system was successfully applied in the advanced treatment of bio-treated effluents of printing and dyeing wastewater, and effectively removed the main disinfection byproduct (DBP) precursors. Operating at FeSO4·7H2O dosage 1.0 g L-1, n(CaO2/Fe2+) 8:1, pH 4.0 and reaction time 1.5 h, about 84.2% of chemical oxygen demand (COD), 82.1% of colority were removed and an increase of the survival rate of Daphnia magna from 20% to 45% was achieved. The degradation of bio-treated effluents of printing and dyeing wastewater by sub-micron CaO2/Fe2+ oxidation system was described by a pseudo second-order kinetic. Compared with the protein-like extracellular organic matter and soluble microbial products (SMPs), fulvic acid-like substances and humic acid-like substances were more easily removed using the oxidation system. The effluent quality meets the reuse of urban recycling water-water quality standard for industrial uses (GB/T 19923-2005, in Chinese).

Advanced oxidation processes perspective regarding swine wastewater treatment

Pork production involves the generation of wastewater containing a high pollutant load. Besides, the intensive use of pharmaceutical products is leading to the effluents rich on these compounds. The traditional treatments involving biological depuration are effective on the removal of the organic load of swine wastewater. However, the time and space required along with the low efficiency on abating persistent contaminants such as pharmaceutical compounds lead to the need of pursuing alternative technologies. Advanced oxidation processes (AOPs) are widely used in the treatment of different types of effluents. AOPs are very efficient and require a short period of treatment time when compared to traditional processes without the production of biological sludge. This review addresses different treatment approaches for swine wastewater treatment focusing on pharmaceuticals removal. The performance of AOPs such as Fenton (H 2 O 2 and Fe +2 ions), photo-Fenton, ozone (O 3 ), electrooxidation and photocatalysis are compared with electrocoagulation and biological systems. A promising alternative is the combination of different technologies taking advantage of their synergies. Finally, an approach to future challenges is discussed. • Pork meat, the second most consumed, is associated with a very problematic effluent • Antibiotics and non-biodegradable contaminants inhibit total effluent bio-treatment • Advanced oxidation processes appear as a non-selective and efficient alternative • Integration of oxidation and biological treatments improves efficiency • Water and other resources recovery may be a suitable management strategy

Spectral studies of Amaranthus tristis Linn. in Bioremediated Silk dyeing effluent with mixed biofertilizer inoculants.

Microbial degradation as a treatment, with the combination of mixed inoculants of the Biofertilizer of Pseudomonas sp., Azospirillium sp. and Rhizobium sp., was employed for the remediation of Silk dyeing effluent. Remediating studies was undertaken to assess the feasibility of the mixed biofertilizer inoculant source for degradation of the Azodye effluent from the Silk dyeing Industry. The Green leafy vegetable (GLV), Amaranthus tristis Linn used as investigational prototypical plant species is selected for examining the phytochemicals, functional groups and its compounds grown in the effluent and biotreated environment and compared. The laboratory scale investigation showed that leaves, stem and root of the Amaranthus tristis Linn was qualitatively analysed for 20 phytochemicals which was grown in the different treatments of raw effluent and the biotreated effluent and the results showed the phytochemicals on the effluent’s influence reduced from strong positive to trace amounts while recovered on the biotreated environment. The FTIR analysis of the GLV grown in effluent and biotreated environments on comparison resulted in the functional group Alkene rescued in the biotreated effluent environment compared to the effluent contaminated area. The HPLC analysis of methanolic extracts of A. tristis grown in fresh water has 6 peaks of retention time of 2.6, 3, 3.9, 4, 4.2, and 4.6 RT whereas GLV effluent had only one peak of retention time of 4.1 RT. In the GLV from biotreated environment have 4 peaks were found with the maximum percentage area of 95.2% which proves that the compounds are rescued in the biotreated environment and few active compounds were confirmed in GCMS analysis. The Soil analysis results also indicate that the biotreatment of mixed inoculant of biofertilizers in the biotreated soil had influence resulting in improved levels of Ca, N, P and K with 114, 213, 10.5, 268 kg/ha respectively in the mixed inoculant biotreated soil. Similarly the micronutrients suchas Fe, Mn, Cu and Zn ranges to 4.1, 20.22, 2.13, 1.13 ppm respectively in the mixed inoculant biotreated soil within the optimal range. The study revealed that mixed biofertilizer inoculant has the recovery effect on the Silk dyeing (Azodyes) effluents effective reducing the pollutant capacity thereby meeting the discharged standards.

Biosorption performance and cell surface properties of a fungal-based sorbent in azo dye removal coupled with textile wastewater

In this work, the biosorption ability of Sarocladium sp. dried biomass to remove Remazol Black dye has been studied. Optimum inoculum size and initial dye concentration were determined, and the salinity effect on the dye removal was evaluated. In the following, kinetic and isotherm of the adsorption were studied, and the adsorbent characteristics were determined using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy, zeta potential, and Brunauer–Emmett–Teller analysis. Based on the results, maximum and minimum dye removal was determined at 1000 and 200 mg L−1 of Remazol Black dye as 54.39 and 24.02 mg g−1, respectively. Among the various azo dyes including Reactive yellow 145, Reactive blue 222, Reactive red 43, Direct blue 21, and Acid blue 161, dye removal capability of 87.96–97.43% was obtained. The solution salinity showed positive effect on the biosorption process. The biomass pretreatment with calcium nitrate enhanced the removal capacity by 70.48% and the maximum reduction in dye removal (− 61%) was obtained when the fungal biomass was treated by sodium hydroxide. Biosorption kinetic follows the first-pseudo-order model, and the obtained data best fits both Langmuir and Freundlich isotherm models. The maximum adsorption capacity of dried biomass for dye removal was 58.48 mg g−1. Based on FTIR, zeta potential value and pretreatment results, Yoshida H-binding, dipole–dipole H-binding, π–π and n–π interactions were probably involved in the dye adsorption process. The results showed that biomass has a high potential for different dyes adsorption from real textile wastewater. The present study declares the high potential of Sarocladium sp. dried biomass as an effective and inexpensive biosorbent which can be used for bio-treatment of effluents with multi-dyes.

Treatment of a slaughterhouse wastewater by anoxic-aerobic biological reactors followed by UV-C disinfection and microalgae bioremediation.

In this study, removal of organic matter and nitrogen from a cattle slaughterhouse wastewater was investigated in a two-stage anoxic-aerobic biological system, followed by UV-C disinfection. Ecotoxicity of the raw, biotreated, and disinfected wastewater against the microalgae Scenedesmus sp. was evaluated in short-term tests, while the potential of the microalgae as a nutrient removal step was addressed in long-term experiments. Throughout 5 operational phases, the biological system was subjected to gradual reduction of the hydraulic retention time (8-1.5day), increasing the organic (0.21-1.11kgCOD·m-3 ·day-1 ) and nitrogen (0.05-0.28kgN·m-3 ·day-1 ) loading rates. COD and total ammoniacal nitrogen (TAN) removal ranged within 83%-97% and 83%-99%, respectively. While providing alkalinity source, effluent TAN concentrations were below 5mg·L-1 . Nitrate was the main nitrification product, while nitrite levels remained low (<1mgN·L-1 ). Upon supplementation of external COD as ethanol, total nitrogen removal reached up to 90% at the highest load (0.28kgN·m-3 ·day-1 ). After UV-C treatment, 3-log reduction of total coliforms was attained. The 96-hr ecotoxicity tests showed that all non-diluted samples tested (raw, biologically treated and UV-C irradiated wastewater) were toxic to microalgae. Nevertheless, these organisms were able to acclimate and grow under the imposed conditions, allowing to achieve nitrogen and phosphorous removal up to 99.1% and 43.0%, respectively. PRACTITIONER POINTS: The treatment of a slaughterhouse wastewater in an anoxic-aerobic biological system followed by a UV-C disinfection step was assessed. The pre-denitrification system showed efficient simultaneous removal of organic matter and nitrogen from the wastewater under increasing applied loads. UV-C disinfection worked effectively in reducing coliforms from the biotreated effluent, boosting the performance of microalgae on nutrients removal. Despite the toxicity to microalgae, they were capable to acclimate to the aqueous matrices tested, reducing efficiently the nutrients content. The combined stages of treatment presented great capacity for depleting up to 97% COD, 99% nitrogen, and 43% phosphorous.

Biodegradation of Methylene Blue as an Evidence of Synthetic Dyes Mineralization during Textile Effluent Biotreatment by Acinetobacter pittii

We investigated the textile effluent decolorization potential of Acinetobacter pittii isolated from dye house effluent (DHE), its ability to degrade methylene blue (MB) and to detoxify the DHE. The organism demonstrated 73% decolorization of the effluent within 5 d and MB degradation at 76% and 84% in 5 and 24 h, respectively. The organism preferred peptone water and nutrient broth to other media and had an optimum pH and temperature of 7.5 and 38 oC, respectively. Fourier transform infrared spectrometry (FTIR) analysis of the MB when compared to that of its metabolites revealed the reduction in intensity and disappearance of specific peaks, particularly those corresponding to the aromatic C–H bending around 600–800 cm− 1. Gas chromatography-mass spectrophotometry (GCMS) results of the degraded MB dye revealed several metabolites. Prominent among these is 6-methyl-2,3-dihydro-1,4-thiazin-1-ium, with m/z value of 114 that is less than half of the MB molecular mass, thus suggesting biodegradation of MB. The pathway of the MB biodegradation was proposed based on identified metabolites from the GCMS results. Phytotoxicity studies revealed that the metabolites of the DHE biotreatment were not toxic to the germination and growth of Zea mays and Vigna unguiculata, unlike the DHE itself, thus proving that this strain of Acinetobacter pittii has the potential to decolorize, degrade and detoxify dyes in textile effluent.

Removal of refractory organics from piggery bio-treatment effluent by the catalytic ozonation process with piggery biogas residue biochar as the catalyst

After anaerobic-oxic (A/O) treatment, there are often high chromaticity levels in piggery bio-treatment effluents, which still contain a high concentration of refractory organics. This paper describes the use of piggery biogas residue biochar (BioC) to support MnO2 to prepare a catalyst (MnO2/BioC) and examines the effects of catalyst addition, pH and ozone dosage on chromaticity and organic matter degradation in the ozonation process. Three-dimensional fluorescence spectroscopy (3D-EEM) and GC-MS were used to analyse changes in the organic component of the effluent before and after ozonation. The results indicate that the decolorization percentages reached 91.29% and that the UV254 and CODcr removal percentages reached 81.64% and 61.07%, respectively, when the MnO2/BioC catalyst addition amount was 1.0g·L-1, the pH was 9.0, and the ozone dosage was 0.45g·L-1. The 3D-EEM analysis results showed that the macromolecular organics mainly consisted of humic acids before treatment, and the removal of humic acid organic matter after treatment had an obvious effect. The GC-MS analysis results showed that the refractory organics were mainly phenols, esters, alcohols and hydrocarbons, and most of the refractory organics were oxidatively degraded after treatment. These results show that ozone catalytic oxidation treatment of piggery bio-treatment effluent can reduce chromaticity and refractory organics.

Tertiary treatability of molasses secondary effluents for color and organics: performance and limits of ozonation and adsorption

Molasses wastewaters (MWWs) such as baker’s yeast and distilleries effluents are usually pretreated by anaerobic, followed by aerobic biodegradation. This removes almost all the BOD, enough for meeting the current discharge standards in many low- and middle-income countries. However, as shown in the present work, the biotreated effluent still contains high levels of recalcitrant COD, color (melanoidins) and inorganic salts that end up in rivers (approx. 1000 mg/L COD, 2850 Pt–Co color units, 5000 mg/L TDS and 5400 μS/cm conductivity). To address this global problematics, and given the lack of proven cost-effective advanced treatment trains for MWW, this study assessed the performance and limits of ozonation and activated carbon (AC) adsorption (contrasting with O3 applications on raw MWW). The applied versus the reacted O3 doses were quantified, allowing also to estimate the ozone uptake rate as a new tool for characterizing the reactivity of the wastewaters. The effects of the treatments on different key parameters were studied: COD, color, aromaticity (UV254 nm), toxicity (Microtox) and biodegradability (by respirometry). O3 reduced the color (> 95%), but causing low COD mineralization (< 35%) and biodegradability enhancement (only 8% more). Meanwhile, adsorption was efficient on both COD and color (97–91%), but needing high AC dosage. In consequence, a more sustainable treatment train was suggested, i.e., upgrading the activated sludge with aerobic granular sludge technology and transforming the granules into AC.

Application and Mechanism of Sludge-Based Activated Carbon for Phenol and Cyanide Removal from Bio-Treated Effluent of Coking Wastewater

The toxic pollutants phenol and cyanide in the bio-treated effluent of coking wastewater still need advanced treatment to meet environmental requirements. In this study, activated carbon prepared from municipal sludge and bamboo waste (SBAC) was used for simultaneous adsorption of phenol and cyanide from bio-treated effluent of coking wastewater. The results showed that the optimum removal efficiencies of volatile phenol (69.7%) and total cyanide (80.1%) were observed at a SBAC dosage of 8 g/L, a pH value of 8.0, and a contact time of 80 min. The physical and chemical properties of SBAC were analyzed using Brunauer–Emmett–Teller (BET) surface area (SBET), scanning electron microscopy (SEM), and Fourier transform infrared (FTIR) spectroscopy. SBAC had high SBET (289.58 m2/g) and rich mesoporous structure (average pore diameter of 3.688 nm), and carboxylic groups on SBAC surfaces were enhanced due to the addition of bamboo waste. In addition, a kinetic model of pseudo-first-order fitted well with the experimental data of volatile phenol, while the adsorption of total cyanide onto the SBAC was better described by a pseudo-second-order kinetic model.

UASB-modified Bardenpho process for enhancing bio-treatment efficiency of leachate from a municipal solid waste incineration plant

Generally, the bio-treatment effluent of municipal solid waste incineration (MSWI) leachate was difficult to meet the local leachate discharge standards for chemical oxygen demand (COD) (100 mg/L), ammonia nitrogen (NH4+-N) (25 mg/L), and total nitrogen (TN) (40 mg/L), and advanced treatment (such as coagulation, membrane filtration, advanced oxidation) is required. However, the cost of advanced treatments is proportional to the concentration of the pollutant. Therefore, improved bio-treatment efficiency is the key to reduce the treatment cost of MSWI leachate. In this study, the up-flow anaerobic sludge blanket (UASB) -modified Bardenpho process was used for the treatment of MSWI leachate. The results showed that it was feasible to dilute the leachate by recirculation of the settling tank effluent, which has great significance in the bio-treatment efficiency. The treatment process achieved removal efficiencies of COD and NH4+-N of 97.5-99.5% and 99.3-99.7%, respectively. Adjustments to the operational conditions of the primary anoxic tank, such as adding an organic carbon source and increasing the hydraulic retention time and the nitrification reflux ratio resulted in a TN removal efficiency of 97.7-98.7%. Controlling the generation of dissolved organic nitrogen (DON) and increasing its removal efficiency significantly improved the TN removal efficiency. The concentrations of NH4+-N and TN in the settling tank effluent complied with the local leachate discharge standard, which minimized the cost of advanced treatment. The results provide new ideas for enhancing the bio-treatment efficiency of leachate and theoretical and technical support for reducing the cost of treatment.

Synthesis of Petal-Like MnO2 Nanosheets on Hollow Fe3O4 Nanospheres for Heterogeneous Photocatalysis of Biotreated Papermaking Effluent.

Owing to the implementation of increasingly stringent water conservation policies and regulations, the pulp and paper mill industry must make increased efforts to meet the limits for pollutant emissions. The primary pretreatment and secondary biochemical treatment methods used currently generally fail to meet the country-specific environmental regulations, and the wastewater must be processed further even after being subjected to secondary biochemical treatments. In this work, we synthesized Fe3O4/MnO2 nanocomposites (FMNs) with a flower-like structure for use in the heterogeneous photocatalytic treatment of biotreated papermaking wastewater. FMNs1.25, which were formed using a KMnO4/Fe3O4 molar ratio of 1.25, could be separated readily using an external magnetic field and exhibited higher photocatalytic activity than those of the other samples as well as MnO2 and Fe3O4. The effects of various experimental parameters on the photocatalytic activity of FMNs1.25, including the initial pH of the wastewater and the catalyst dosage, were determined. The common chemical oxygen demand (CODCr) reduction rate in the case of this sample reached 56.58% within 120 min at a pH of 3, the CODCr of effluent after treatment was 52.10 mg/L. Further, even under neutral conditions, the CODCr of the treated effluent was below the current limit for discharge in China. Moreover, the nanocomposites exhibited good recyclability, and their catalytic activity did not decrease significantly even after five usage cycles. This study should serve as a platform for the fabrication of effective photocatalysts for the advanced treatment of biotreated papermaking effluent and refractory organic wastewater.

Post-treatment of bio-treated acrylonitrile wastewater using UV/Fenton process: degradation kinetics of target compounds.

In this study, post-treatment of bio-treated acrylonitrile wastewater was performed using the UV/Fenton process. Five target compounds (furmaronitrile, 3-pyridinecarbonitrile, 1,3-dicyanobenzene, 5-methyl-1H-benzotriazole, and 7-azaindole) were selected as target compounds and their degradation kinetics were examined. Under optimal reaction conditions (H2O2 dosage 3.0 mM, Fe2+ dosage 0.3 mM, and initial pH 3.0), more than 85% of total organic carbon (TOC) was eliminated in 30 min when a 10-W UV lamp was employed, and the electrical energy per order of magnitude for TOC removal was as low as 2.96 kWh m-3. Furthermore, the target compounds and the toxicity were largely removed from the bio-treated effluent. Size exclusion chromatography with organic carbon detector analysis revealed that organic components with a wide range of molecular weights were greatly reduced after the UV/Fenton process. A simplified pseudo steady-state (SPSS) model was applied to predict the degradation of target compounds during the UV/Fenton process. The concentrations of generated hydroxyl radicals were estimated to be 3.06 × 10-12 M, 6.37 × 10-12 M, and 10.9 × 10-12 M under 5-, 10-, and 15-W UV lamps, respectively. These results demonstrate that the proposed SPSS model fitted well with experimental data on the post-treatment of real wastewater, and consequently indicate that this model can be a useful tool in the prediction of degradation of target compounds during the UV/Fenton process.

From agro-waste to tool: biotechnological characterization and application of Ganoderma lucidum E47 laccase in dye decolorization.

The culture of fungal species from agro-waste allows for the sustainable preparation of valuable biotechnological products and contributes to establish the Circular Economy concept. The Ganoderma lucidum species is well known as producer of laccases (EC 1.10.3.2), which serves as a tool to oxidize chemicals. When producing G. lucidum E47 basidiomes with edible purposes out of rice crop residues, its laccase remains as by-product. In this work, we report the biotechnological characterization and application of the laccase recovered from spent cultures of the G. lucidum E47 strain. We detected at least one polypeptide (ca. 59kDa) which displays attractive activity and stability values when used in the range of 18-45°C in mildly acidic environment (pH 4.8-5.8). These parameters can be enhanced in the presence of organic cosolvents such as butyl acetate and methyl iso-butyl ketone, but the opposite effect is observed with solvents of lower log P. The best activity-stability performance is reached when the biocatalyst is used in pH 4.8 buffer with 5% (v/v) butyl acetate at 37°C. The laccase was capable of decolorizing xanthene, azo and triarylmethane dyes, exhibiting excellent selectivity on bromocresol green and bromocresol purple. Furthermore, the biocatalyst displayed an attractive activity when assessed for the decolorization of bromocresol green in a proof-of-concept effluent biotreatment.

Fourier Transform Infrared (FTIR) Spectroscopy and High-Performance Liquid Chromatography Analysis of Brassica juncea (Mustard) and Silk dye-ing effluent’s impact on the spectral studies

The exclusive, low-cost nominal technology for the meagre entrepreneurs of Silk dyeing effluent has been planned and executed. Environmental pollutants exit like Silk dyeing effluent are destructive and needs a high-cost Common Effluent Treatment Plant (CETP) to achieve Zero effluent discharge limits which are not reasonably priced for a low venture capitalist. The Green leafy vegetable Brassica juncea sowed seeds were treated in pot study with fresh water, raw Silk dyeing effluent and Biotreated effluent (with Pseudomonas fluorescens and Azospirillum sp. biofertilizers separately). After 45th days the GLV’s extracts Brassica juncea were grown in fresh water (BJN), in crude effluent (BJE) and in biotreated effluent (BJT) were subjected to UV, FTIR and HPLC analysis. Thus from the functional group studies by FT-IR, the alcohol, alkane, alkyl halide and amine groups were found in GLV irrespective of the treatments, even in crude effluent, the plants managed to synthesize these organic compounds. The isocyanide group was found only in B. juncea, grown in fresh water, which was unable to synthesize isocyanide group in plants grown in crude effluent and biotreated effluent. While the biotreated B. juncea methanolic extracts had shown two peaks of similar to the freshwater B.juncea methanolic extracts whereas the crude effluent had its effect in HPLC Analysis. So it clearly indicates that the effluent's effects have been encountered by the Pseudomonas fluorescens.

Preparation and Characterization of Cu-Mn-Ce@γ-Al2O3 to Catalyze Ozonation in Coal Chemical Wastewater-Biotreated Effluent.

Cu-Mn-Ce@γ-Al2O3 was prepared by incipient wetness impregnation and used to catalyze ozonation in a coal chemical wastewater-biotreated effluent. The preparation factors that considerably affected the catalytic performance of Cu-Mn-Ce@γ-Al2O3, specifically metal oxide loading percentage, calcination temperature, and calcination time, were examined. The catalyst was characterized by scanning electron microscopy, energy dispersive spectrometry, X-ray diffraction, and Brunauer-Emmett-Teller analysis. The optimal catalytic ozonation operating parameters, such as ozone dosage, catalyst dosage, pH, and reaction time, were also investigated. Results showed that an optimized catalyst consisted of 17.0% CuO, 3.0% MnO2, and 2.0% CeO2 (wt.%). The optimal calcination temperature and calcination time were 600 °C and 5 h. The optimal catalytic ozonation operating parameters, including ozone dosage, catalyst dosage, pH, and reaction time, were 7, 80.0 mg/L, 20.0 mg/L, 7 and 50 min, respectively. The COD removal of biotreated effluent increased to 61% under these optimal operating conditions. Meanwhile, ozonation alone resulted in only 20% removal. This work proposes the use of easily available Cu-Mn-Ce@γ-Al2O3 catalyst and might drive the advancement of catalytic ozonation for chemical wastewater purification.

Energy Balance Evaluation in Coking Wastewater Treatment: Optimization and Modeling of Integrated Biological and Adsorption Treatment System

The main objective of this study is to develop and assess a novel wastewater treatment system for coking wastewater to enable maximization of net energy gain. Additionally, a new methodology is proposed for evaluation of energy saving. The new combined biotreatment and adsorption system (A2BA1) is designed with two adsorption reactors placed at the input and output of the biotreatment unit. An energy modeling coupled mathematical simulation (EMMS) methodology is proposed for assessment of the energy balance. The optimal operating conditions (OOCs) are achieved and energy saving rates (ESRs) can also be calculated in the proposed methodology. The results showed that the A2BA1 system enabled energy savings in treatment of volume loads of chemical oxygen demand (COD) and NH3-N in the range 0.82–2.96 kg COD/(m3·d) and 0.06–0.15 kg NH3-N/(m3·d), respectively. Using the EMMS methodology, the operating condition sets of Q18(2506.9, 104.2, 0.98), Q33(3008.1, 101.1, 2.00), and Q36(2524.3, 102.6, 2.02) were found to be the OOCs, and the average value of ESRs of the three OOCs reached 48.3%. In this work, Qi stood for the mathematical set of the ith operating condition comprised of the basic variables (i.e., raw wastewater COD (mg/L), biotreated effluent COD (mg/L), and activated carbon dosage (g/L)). Furthermore, in order to realize net energy gain in the coking wastewater treatment, the adsorbent price of activated carbon should be 54% of the current price for the same adsorption performance. It is concluded that the A2BA1 system and EMMS methodology can help decision-makers design and optimize wastewater treatment in terms of energy savings.