Maximum COD Removal Rate Research Articles

Catalytic ozonation of reverse osmosis membrane concentrates by catalytic ozonation: Properties and mechanisms.

Ni-Mn@KL ozone catalyst was prepared for the efficient treatment of reverse osmosis membrane concentrates. The working conditions and reaction mechanism of the ozone-catalyzed oxidation by Ni-Mn@KL were systematically studied. Then, a comprehensive CRITIC weighting-coupling coordination evaluation model was established. Ni-Mn@KL was characterized by scanning electron microscopy, BET, X-ray diffraction, X-ray photoelectron spectroscopy, energy-dispersive spectrometry, and X-ray fluorescence spectrometry and found to have large specific surface area and homogeneous surface dispersion of striped particles. Under the optimum working conditions with an initial pH of 7.9 (raw water), a reaction height-to-diameter ratio of 10:1, an ozone-aeration intensity of 0.3L/min, and a catalyst filling rate of 10%, the maximum COD removal rate was 60.5%. Free-radical quenching experiments showed that OH oxidation played a dominant role in the Ni-Mn@KL-catalyzed ozone-oxidation system, and the reaction system conformed to the second-order reaction kinetics law. Ni-Mn@KL catalysts were further confirmed to have good catalytic performance and mechanical performance after repeated utilization. PRACTITIONER POINTS: Ni-Mn@KL catalyst can achieve effective treatment of RO film concentrated liquid. High COD removal rate of RO membrane concentrated liquid was obtained at low cost. Ni-Mn@KL catalyst promotes ozone decomposition to produce ·OH and O2 -· oxidized organic matter. The Ni-Mn@KL catalyst can maintain good stability after repeated use. A CRITIC weight-coupling coordination model was established to evaluate the catalytic ozonation.

In Situ Utilization of Electron-Enhanced Degradation of Azo Dyes in a Constructed Wetland–Microbial Fuel Cell Coupling System

In this study, a constructed wetland was coupled with a microbial fuel cell to establish a coupled system known as the constructed wetland–microbial fuel cell (CW–MFC), utilized for the treatment of X-3B azo dye wastewater at varying concentrations. Experimental results indicated that the anodic region made the primary contributions to the discoloration of azo dyes and COD removal, with a contribution rate of 60.9–75.8% for COD removal and 57.8–83.0% for the effectiveness of discoloration. Additionally, the role of plants in the constructed wetland area could achieve the removal of small molecular substances and further discoloration. In comparison to open-circuit conditions, under closed-circuit conditions the CW–MFC effectively degraded X-3B azo dye wastewater. Under an external resistance of 2000 Ω, a maximum COD removal rate of 60.0% and a maximum discoloration rate of 85.8% were achieved for X-3B azo dye at a concentration of 100 mg/L. Improvements in the treatment efficiency of X-3B dye wastewater were achieved by altering the external resistance. Under an external resistance of 100 Ω and an influent concentration of X-3B of 800 mg/L, the COD removal rate reached 78.6%, and the decolorization rate reached 85.2%. At this point, the CW–MFC exhibited a maximum power density of 0.024 W/m3 and an internal resistance of 99.5 Ω. Spectral analysis and GC–MS results demonstrated the effective degradation of azo dyes within the system, indicating azo bond cleavage and the generation of numerous small molecular substances. Microbial analysis revealed the enrichment of electrogenic microorganisms under low external resistance conditions, where Geobacter and Trichococcus were dominant bacterial genera under an external resistance of 100 Ω, playing crucial roles in power generation and azo dye degradation within the system.

Degradation of methylene blue through atmospheric pressure glow discharge plasma treatment

The degradation of Methylene Blue (MB) dye through treatment with an atmospheric pressure glow discharge plasma is presented in this work. The set-up used in this work has the advantage of being very simple without any gas supply. Plasma was diagnosed using optical emission spectroscopy, and rotational temperature of the hydroxyl radicals was measured. The effects of plasma current, treatment time, polarity and material of the electrodes on degradation of MB dye were studied. Experimental results showed that the degradation of dye increased with plasma current and treatment time. Polarity of the electrodes also have an effect in that the liquid cathode mode has about 14% higher degradation efficiency than liquid anode mode. Interestingly, it was found that anodic dissolution of copper electrode aids in degradation of MB dye by initiating Fenton like reactions involving copper ions, which was absent in the case of stainless steel electrode. After 40 min of treatment, the maximum degradation efficiency and COD removal rate achieved was 77% and 74% respectively, while the degradation yield obtained was 0.32 g.kW–1.h–1.

Solids Reduction Process for Agricultural Effluent – A Laboratory Feasibility Study

Process steps of flocculation, filtration and centrifugation are investigated to better utilizing existing storage capacity of agriculturally based effluents and at the same time minimize the environmental impact of agricultural operations.
 As flocculant Ca(OH)2 as a 20% solution, FeCl3 as a 30% solution, and Al2(SO4)3 as a 20% solution were used.
 The solids content of the liquid manure, having a preadjusted pH of 9.5, resulted in a solids reduction of up to 46.8% with centrifugation.
 For all flocculants, the 20% Ca(OH)2 solution, the 30% FeCl3 solution, and the 20% Al2(SO4)3 solution resulted in a decrease of the solids content of the liquid manure.
 FeCl3 as flocculant reduced the solids content by 45%, Al2(SO4)3 and Ca(OH)2 as flocculant by 21.0% after the second centrifugation process. Filtration as the fourth process step reduced the solids content further by 31.6% for the Ca(OH)2 flocculant, whereas for FeCl3 and Al2(SO4)3 as flocculant and increase of the solids content by 18.2% and 2.5% respectively resulted.
 The flocculant Ca(OH)2 outperformed FeCl3 and Al2(SO4)3 by 71.2%, 65.4%, and 56.9% respectively.
 A Maximum COD removal rate of 47/8% could be realized without flocculant and 70.6% COD removal rate could be utilized using FeCl3 as flocculant applying a second centrifugation process.

An electricity-generating bacterium separated from oil sludge microbial fuel cells and its environmental adaptability.

Electricity-generating bacteria as biocatalysts for microbial fuel cells (MFCs), their species, and power generation performance determine the pollution control and power generation performance of MFCs. And there are few studies on the types and performance of electricity-generating bacteria isolated from oily sludge microbial fuel cells. For improving the power generation performance of oily sludge MFCs, an electricity-generating bacterium was isolated from the oily sludge. More importantly, the adaptability of nitrogen to phosphorus ratio, temperature, and pH of the electricity-generating bacteria were adjusted by a controlled variable method. The results of this study showed that the electricity-generating bacterium was identified as Bacillus cereus, with a rod-shaped cell, about 0.5-1.0μm in length. The optimal nitrogen-phosphorus ratio, temperature, and pH of MFCs were 4.67:1, 25 ℃, and pH = 7, respectively. Its maximum power density, COD, and oil removal rate was up to 65 mW·m-3, 90.51%, and 87.76%, respectively. The study of this functional bacterium will provide beneficial assistance for the improvement of oil removal and power generation performance of oily sludge MFCs.

Microalgae cultivation in domestic wastewater for wastewater treatment and high value-added production: Species selection and comparison

In this study, six freshwater microalgae, including Scenedesmus sp. LX1, R. subcapitata, T. obliquus, Chlorella sp. HL, Chlorella sp. (A), and Chlorella sp. (B), were appraised for growth, nutrient removal, and high value-added productions in municipal domestic wastewater to select the species with greatest utilization potential. The results showed that after 10 d of cultivation under the sterilized condition, Chlorella grew better than others and Chlorella sp. HL obtained the highest algae density (2.44 × 107 cells/mL). The maximum biomass obtained from Scenedesmus sp. LX1 was 0.55 g/L. The maximum COD removal rate was achieved by R. subcapitata (79.01 %). Scenedesmus sp. LX1 showed excellent NH4+-N and TP remove capacity and achieved the highest removal rate (93.81 % and 87.72 %, respectively) eventually. The harvested biomass was found to accumulate high value-added products, especially protein, with a highest content of 54.64 %, which was observed in T. obliquus. Under the sterilized condition, Scenedesmus sp. LX1 was considered as the optimal candidate for municipal domestic wastewater treatment. Under the non-sterilized condition, Chlorella sp. HL was found to perform better than Scenedesmus sp. LX1 and T. obliquus no matter water purification, algal growth, and high value-added products accumulation.

Leachate post treatment, using Ag-TiO2 nanoparticles immobilized on rotating vanes

The current study investigated the capability of Ag-TiO2 nanoparticles in photocatalytic landfill leachate post-treatment. Silver doped Titanium dioxide nanoparticles were coated on rotating vanes and used in an immobilized photoreactor for the first time. The system's efficiency in COD, color, turbidity, and TOC removal, was monitored, and the effect of different parameters including pH, coating surface area, and concentration of immobilized nanoparticles was investigated. Based on the results, the maximum COD, color, turbidity, and TOC removal rates were 62%, 66%, 53%, and 55%, respectively, after 4 h of irradiation under optimal conditions. Experimental data on COD removal were also compared with the first and second-order kinetic models and it was concluded that the degradation process is more compatible with the second-order model. Finally, vanes' durability was tested, and according to the results, each set of vanes was capable of being used for at least six consecutive cycles with a negligible decrease in the treatment efficiency. In comparison with pure TiO2, the synthesized Ag-TiO2 nanoparticles showed higher removal rates in equivalent time intervals, and the whole system proved to be a promising post-treatment approach.

Enhanced treatment of organic matters in starch wastewater through Bacillus subtilis strain with polyethylene glycol-modified polyvinyl alcohol/sodium alginate hydrogel microspheres

Starch wastewater is a wide range of environmental issues with organic pollutants. A high efficiency and stability hydrogel-organic degradation system was designed via Bacillus Subtilis with Polyethylene glycol (PEG)-modified Polyvinyl alcohol (PVA)/Sodium alginate (SA) hydrogel microspheres. Bacillus subtilis was immobilized on the surface or inside of PEG-modified PVA/SA hydrogels microspheres via physical adsorption. Results showed PEG-modified PVA/SA microspheres had an effect of adsorption on Bacillus subtilis with enhancing bearing rate to 54.22% compared to the blank control group. The effect of microspheres on degradation was remarkable in simulation starch wastewater with a maximum COD removal rate of 93.35% and compared in reality starch wastewater with 90.02% under the optimal condition of pH = 6, 35℃, 20% dosage, 180 rpm. This novel biological method on starch wastewater enhanced tolerance of microorganisms and degradation effect, reflecting safety, effectiveness, and economy with great significance to environmental protection.

Efficiency of ozonation process with calcium peroxide in removing heavy metals (Pb, Cu, Zn, Ni, Cd) from aqueous solutions

Heavy metal ions have deadly effects on all forms of life, and through the disposal of industrial wastewater, they enter water resources and, eventually, the food chain. Advanced oxidation processes can remove hazardous and non-degradable organic pollutants in aqueous solutions. Variables examined were initial concentrations of calcium peroxide and heavy metals, contact time, pH, and ozonation rate. Maximum removal rate of heavy metals by ozonation with calcium peroxide under optimal conditions (contact time = 90 min, pH = 3, heavy metal concentration = 25 mg/L, calcium peroxide concentration = 0.025 mg/L and ozonation rate = 1 g/min) in synthetic and real samples were respectively 89.8% and 64.6% for Pb, 92.1% and 73.9% for Cu, 90.4% and 69.7% for Ni, 86.9% and 59.1% for Cd, and 93.4% and 78.8% for Zn. Maximum COD removal rates in synthetic and real samples were 88.1% and 69.9%, respectively. Removal rates of heavy metals and COD under optimal conditions on wastewater from the Isfahan electroplating industry and steel company were determined. The use of the ozonation process with calcium peroxide can be recommended as a good, coefficient method for the removal of heavy metals in wastewater treatment.

Kinetic of denitrification and enhanced biological phosphorous removal (EBPR) of a trickling filter operated in a sequence-batch-reactor-mode (SBR-TF)

ABSTRACT Due to their limited ability for nutrient removal, trickling filter systems (TFS) have almost fallen into oblivion today, even though they are robust and energy-efficient treatment systems. The advantage of this process technology, however, is the sessile biomass, which allows long periods of starvation without rinsing out the biomass. Therefore, this technology is promising for treating organic-polluted, intermittent stormwater-runoff. Several combinations with activated sludge systems (ASS) use the trickling filter as pre-treatment, requiring two separate treatment systems. This combines the advantages of both systems, but is paid with increased investment costs and space requirement. Due to these concerns, a trickling filter was developed that allows a nutrient removal without an additional ASS and exemplary tested for treating stormwater runoff of a silo facility. Beside aerobic conditions, anoxic and anaerobic steps have to be ensured during the process for nutrient removal. For this, the TFS is ponded with a mix of purified wastewater from the secondary clarification tank (containing nitrate) and untreated raw water (containing degradable COD). This allows both, an integration of upstream-denitrification and enhanced-biological-phosphorous-removal (EBPR). During the anoxic step, nitrate removal rates of 0.8 kgCOD m−3 d−1 can be expected, whereas a maximum COD removal rate of 4.5 kgCOD m−3 d−1 are achieved. To support complete nitrification of ammonia, a COD removal rate below 0.5 kgCOD m−3 d−1 is recommended. The anaerobic/aerobic PO4 uptake rate of the EBPR was 31%. These results show that a combination of trickling filter with ASS in one single reactor is feasible.

Degradation of high-chemical oxygen demand concentration pesticide wastewater by 3D electrocatalytic oxidation

The treatment of difficult biodegradable industrial wastewater by electrocatalytic oxidation technology has positive significance for the prevention and control of industrial pollution. In this study, particle electrode Ti–Ag/γ-Al2O3 was prepared and used as a catalyst in the 3D electrocatalytic oxidation reaction system for pretreatment of high-chemical oxygen demand (COD) concentration pesticide wastewater. Electrolysis conditions for high-COD concentration pesticide wastewater were discussed and optimized, and single-factor experiment results showed that the maximum COD removal rate was 82.50% with an energy consumption of 10.91 (kW h) kg−1 COD at conductivity of 4000 μS cm−1, current density of 30 mA cm−2, initial pH of 2.0, electrode distance of 3.0 cm, air flow of 3.0 L min−1, and filling proportion of 50.0%. The UV–visible absorption spectrum analysis of pesticide wastewater at different electrolysis times showed that the organic macromolecules containing long-chain, heterocyclic, and other structures were degraded into small molecular organic compounds. After the 3D electrocatalytic oxidation reaction, the BOD5/COD value of pesticide wastewater increased from 0.041 to 0.308, indicating that the biodegradability of the pesticide wastewater was improved significantly.

Remediation of simulated malodorous surface water by columnar air-cathode microbial fuel cells

Malodorous surface water is an important worldwide environmental concern. Current remediation methods, such as aeration or the addition of chemicals, are not eco-friendly due to their high energy consumption or secondary pollution. This study proposed a modified columnar air-cathode microbial fuel cell as a sustainable and effective remediation module to improve water quality. The excellent and economic sheet air-cathode (activated carbon and carbon black as the catalyst layer) and a carbon brush anode were applied in the columnar air-cathode microbial fuel cell (MFC). The results after 48 h showed that by providing the anode as an electron acceptor and enriching electrochemically-active bacteria, MFCs with different external resistances (5 k Ω, 30 Ω, and 2 Ω) exhibited the much better capacity to improve water quality than the Blank group. The maximum COD and sulfide removal rates in the MFCs were approximately 86.3% and 100%, respectively, which were higher than those of the Blank group by 30% and 35%, respectively. The MFCs also showed maximum sulfate increments from 28 mg L−1 to 98 mg L−1 compared with the sulfate reduction to 10 mg L−1 in the Blank group. The oxidation reduction potential (ORP) of the MFCs dramatically increased from −281.2 mV to −135.7 mV after 24 h, whereas the ORP of the Blank group decreased to −287.7 mV. The enrichment of the aerobic bacteria Acinetobacter on the anodes and chemolithoautotrophic sulfide oxidation bacteria Sulfuricurvum, Thiovirga and Thiobacillus in the MFCs could also contribute to COD and sulfide removal. Cathode reduction, which could produce small amounts of hydroxyl radicals, might assist with the ORP elevation and the complete oxidation of dissolved sulfide to sulfate.

Modeling the kinetics and cost performance index of high rate up‐flow anaerobic, anoxic, oxic bioreactor for meat wastewater treatment

AbstractThe simultaneous biological removal of COD, TN and phosphorus from meat industrial wastewater (MIW) using a lab‐scale high rate up‐flow anaerobic–anoxic–oxic bioreactor (A2O bioreactor) was investigated. The bioreactor was operated at different HRT, COD/TN ratio and aerated volume fractions to monitor the COD and nutrient removal efficiency. The maximum COD removal rate was detected at HRT of 5 h and COD/TN ratio of 100 : 12. The total nitrogen removal efficiency was changed between 65.8 and 94.4% and the lowest effluent nitrate concentration was measured as 1.6 mg/l. Seven kinetic models were applied to experimental data to determine the substrate utilization rate. The Monod and Haldane models were ideal to estimate the reactor performance. Moreover, the cost performance evaluation indicated the A2O bioreactor capability in low energy consumption for MIW treatment. According to the modeling results, integrating anaerobic and aerobic zones within a single bioreactor could be beneficial and cost‐effective due to the high effluent quality and low operational costs.

Performance of microbial desalination cell for salt removal and energy generation using different catholyte solutions

Microbial desalination cell (MDC) is a bioelectrochemical process for simultaneous bioelectricity generation, wastewater treatment, and water desalination. The major drawback of MDC improvement is using toxic catholyte solutions which are normally employed in cathode chamber. In this study, the performance of microbial desalination cell using buffer saline solution was investigated for the first time. The obtained results were compared to several low-cost catholyte solutions, including low concentration of phosphate buffer solution (PBS), non-buffer saline solution, and bio-catholyte. All MDC reactors were fed with actual urban wastewater as fuel. Among all examined catholyte solutions, the MDC using bio-catholyte achieved the highest power density of 32.6Wm−3, followed by the MDC using saline buffer catholyte with maximum power density of 29.4Wm−3. Bio-catholyte had also lower internal resistance, and it improved current generation; maximum COD removal and desalination rate were 80% and 0.38g NaClL−1h−1, respectively. On the other hand, in the MDC with buffer saline solution, the COD removal and desalination rate were 73.1% and 0.34g NaClL−1h−1, respectively. In the MDCs using PBS and non-buffer saline solution, maximum power density was 11.1 and 16.3Wm−3, respectively. Based on experimental data, Among the examined catholytes, wastewater as bio-catholyte and saline buffer solution were the desired candidates for MDC scale up, and the most promising point was their being inexpensive alternatives to supplant the costly MDCs catholytes.

Features of Golenkinia sp. and microbial fuel cells used for the treatment of anaerobically digested effluent from kitchen waste at different dilutions

The aim of this work was to study Golenkinia sp. and microbial fuel cells (MFCs) for the treatment of anaerobically digested effluent from kitchen waste (ADE-KW) with different dilution factors. A dual-chamber MFC was fabricated for treating ADE-KW in the two chambers of the MFC and harvesting Golenkinia sp. All the anodic TN was removed more than 80%. COD removal efficiency increased from 48.2% to 76% when the dilution factor increased from 1 to 4. Maximum COD and TN removal rates were 3.56 and 3.71mg·L−1·h−1 when ADE-KW was treated without dilution in the anodic chamber. All the cathodic TN and TP removal efficiencies were approximately 90%. The highest open circuit voltage (OCV) and power density were approximately 400mV and 400mW when ADE-KW was treated directly (undiluted) in the MFC, with the highest biomass and total lipid content production of Golenkinia sp. in the cathodic chamber.

Comparing new perspective of hybrid approach and conventional kinetic modelling techniques of a submerged biofilm reactor performance

This study dealt with modelling a submerged biofilm reactor using three modelling approaches including Artificial Neural Network (ANN), Evolutionary Polynomial Regression (EPR), and Modified Stover Kincannon (MSK). Generally, eight experimental runs were conducted under different operational conditions, i.e., influent COD (at four levels of 200, 300, 400, and 500), aeration rates (at two levels of 4 and 8L/min), and operating run time (20 days). Regardless of specific conditions, the predicted fluctuation of effluent COD by MSK, ANN, and EPR were in the range of 22–104, 12–112, 21–115, respectively while from the experimental data, this values were obtained between 13 and 126. Based on the MSK model, an increasing at aeration rate from 4 to 8L/min causes doubling in the maximum COD removal rate constant (Rmax) from 10.5 to 20.3 (gCOD/Lday). Among the applied models, ANN with minimum normalized Mean Square Error (MSE) of 0.1 showed an accurate prediction effluent COD (R2=0.95); however, it gave no information about reactions occurring in the system. The results suggested that, EPR method with a good coefficient of determination (R2=0.93), the representation of mathematical model expressions and the interpretation of the underlying phenomena is promising modelling technique for prediction of biofilm processes.

The Effects of Temperature on the Performance of Anaerobic Sequencing Batch Reactor in the Treatment of Synthetic Dairy Wastewater

raw wastewater in the primary tank was heated to the desirable temperature and then three more heaters continuously produce the heat in the reactor to operate system at the constant operating temperature in each run. Data were analyzed by SPSS 16through Pearson's correlation coefficient to analyze the association between these parameters. Results: The maximum COD removal rate was 89.7% at the organic loading of 4.5 g/L per day in a 24-hour cycle condition with reaction time of 21 hours and 30 minutes. The maximum biochemical oxygen demand (BOD5) removal rate was 91% and occurred at the first run. The amount of COD removal efficiency was higher at the first run in comparison to the third cycle (27.5%). BOD5 removal efficiency decreased up to 24.4% due to the drop of temperature in the reactor. Pearson correlation analysis showed a significant association between the temperature and the removal efficiencies (P < 0.01). Conclusions: The results of this study indicated that any decrease in the temperature caused reduction in system efficiency of removing BOD5 and COD. Temperature of 35°C is optimal for the removal of high organic load wastewater. ASBR can be used as an effective tool to treat dairy industry wastewater.

Combined treatment of the municipal landfill leachate by fluidized bed Fenton process

Compared to the incineration and composting, landfill was an ordinary technology which is often used in the solid waste disposal. Landfill leachate is highly loaded, toxic, and harmful to the sanitation of wastewater. In past 20 years, technologies such as advanced oxidation processes had been developed for the treatment of wastewater which is contaminated by the hazardous and recalcitrant organic compounds, such as pesticides, surfactants, and pharmaceuticals and endocrine disrupting chemicals, but so far there is little information about the application of fluidized-beds Fenton process in the oxidation treatment of organic compounds from the municipal landfill leachate. In this paper, the effects of different treatments to the municipal landfill leachate from Shaoxing landfill by gas–liquid fluidized bed with Fenton reagent were examined and evaluated. The effects of various operating conditions, such as treatment time, initial COD strength, initial pH value, initial [H2O2], initial [Fe2+], and ventilation volume were examined. After evaluation, several optimal operating conditions (COD = 2500 mg/L, reaction time of 30 min, pH = 2.5, [Fe2+]0 = 0.05 mmol/L, [H2O2]0 = 0.075 mmol/L, ventilation volume of 0.12 m3/h, and temperature = 60°C) were found under which the maximum COD removal rate (61.4%) was obtained.

温度对“SH-A”工艺处理阿托伐他汀钙制药废水的影响研究

本文采用SH-A工艺对处理阿托伐他汀钙制药废水的效果进行了研究，重点研究了温度对SH-A工艺处理阿托伐他汀钙制药废水的影响。实验结果显示：采用SH-A工艺处理阿托伐他汀钙制药废水，能够有效去除废水中的COD和-N；温度对SH-A工艺处理阿托伐他汀钙制药废水具有较大的影响。在给定条件下，对于COD，随着系统温度的升高，COD的去除率明显提高，当温度达到35℃，COD去除率达到最大值，继续升高温度，COD去除率有所降低；对于NH4+-N，随着系统温度的升高，其去除率亦明显提高，当温度达到29℃，-N去除率达到100%，继续升高温度，去除率保持不变。根据实验结果，应选择35℃作为本工艺处理阿托伐他汀钙制药废水的最佳温度。 In this paper, the effect of using SH-A process to treat Atorvastatin Calcium pharmaceutical wastewater is studied. This study mainly focuses on the effect of temperature on the SH-A process. The experimental results show that: the SH-A process has an effective removal of COD and -N; temperature is key factor of the treatment effects. Under the given conditions, the COD removal efficiency improved significantly with the increasing system temperature; the maximum COD removal rate occurred when the temperature reached 35˚C; continued to rise system temperature, COD removal rate decreased. In terms of the -N, with the increase of the system temperature, the removal rate was significantly improved; when the temperature reached 29˚C, -N removal rate reached 100%; continued to rise the temperature, the removal rate remained unchanged. According to the experimental results, the optimal tempera- ture for SH-A process to treat the Atorvastatin Calcium pharmaceutical wastewater should be 35˚C.

Degradation of Disperse Blue 2BLN Dye Wastewater by Pulsed Corona Discharge Combined with Ozone Process

Waste water discharged from dye plant contains high sanity ,high chroma and high CODcr (Chemical Oxygen Demand), commonly used biodegradation is often limited in application; As a new efficient advanced oxidation, pulsed corona discharge combining with ozone is attracting more and more attention. A special reactor was designed, in addition, the removal of COD and decoloration of stimulant dye wastewater containing disperse blue 2BLN dye (100mg/L) by pulsed corona discharge combining with ozone were investigated . It showed that in alkaline solution, the maximum COD removal and decoloration rate(58.8% and 99.1%) was observed ,which demonstrated that ozone and pulsed discharge was more efficient on COD removal and decolouration in alkalin than in neutral solution when all the samples were treated for13mins. After being treated, B/C increased from 0.2 to 0.45. Decoloration efficiency and COD removal could be improved obviously when oxygen feed increased from 40 to80L /h，yet further increase in oxygen feed led to a markedly decrease of decolouration efficiency and COD removal.