scholarly journals Mn/sepiolite as the heterogeneous ozonation catalysts applied to the advanced treatment of regenerated-papermaking wastewater

2016 ◽  
Vol 75 (5) ◽  
pp. 1025-1033 ◽  
Author(s):  
Zheng Cheng ◽  
Rendang Yang ◽  
Yang Wang
Keyword(s):  
Reaction Pathway ◽  
Removal Rate ◽  
Oxygen Demand ◽  
Catalytic Ozonation ◽  
Treated Wastewater ◽  
Precipitation Method ◽  
Advanced Treatment ◽  
Heterogeneous Catalytic ◽  
High Removal Rate ◽  
Papermaking Wastewater

Herein a Mn-deposited sepiolite catalyst was obtained through a facile co-precipitation method, and then used as the heterogeneous ozonation catalysts applied to the tertiary treatment of regenerated-papermaking wastewater. During the process, the as-prepared catalyst was endowed with higher Brunauer–Emmett–Teller specific surface area of 412.3 m2/g compared to 124.6 m2/g of the natural sepiolite. Hence, in the adsorption of methylene blue, the as-prepared catalyst was observed with a very high removal rate of 96.2% although a little lower than the modified sepiolite of 97.5% in 100 min. And for practical application, the catalyst was used for treating the effluent from regenerated-papermaking industry, via a heterogeneous catalytic ozonation process. Consequently, the highest color removal rate of 99.5%, and the highest chemical oxygen demand (COD) removal efficiency of 73.4% were achieved in 20 and 30 min, respectively. As a result, the treated wastewater was more biodegradable and less toxic; the biochemical oxygen demand (BOD5)/COD value could reach 0.41. Moreover, the catalyst showed superior stability at successive ozonation runs. The main possible reaction pathway is also presented. The results indicate that catalytic ozonation was proved to be effective when Mn/sepiolite was used as catalysts applied to the advanced treatment of regenerated-papermaking wastewater.

Advanced Oxidation Treatment of Papermaking Wastewater by Homogeneous Fenton Reaction

2013 ◽  
Vol 726-731 ◽  
pp. 2510-2514 ◽  
Author(s):  
Hong Ping He ◽  
De Li Wu
Keyword(s):  
Removal Rate ◽  
Paper Industry ◽  
First Grade ◽  
Advanced Treatment ◽  
Treatment Processes ◽  
Quality Of Water ◽  
Optimum Reaction ◽  
Oxidation Technology ◽  
Papermaking Wastewater

The quality of water from traditional two-stage biochemical treatment process of papermaking wastewater cannot meet the pollutants discharge standard of paper industry,therefore it is necessary to develop new advanced treatment processes to further treat the effluent. This paper adopts the homogeneous Fenton oxidation technology to treat the effluent from a secondary sedimentation tank of a papermaking factory by batch experiments. The optimum reaction conditions are H2O2dosage 6.54mmol/L, FeSO4.7H2O dosage 200mg/L, pH=3, t=1.5h and of all the experiments the dosage of polyacrylamide is 3ppm. The COD of the treated water is under 50mg/L and its removal rate can reach as high as 75.4%, the chroma almost falls to zero, the effluent meets the first grade of the national wastewater discharge standard. Therefore, the homogeneous Fenton is an effective alternative for papermaking wastewater advanced treatment, due to its high effect.

Experimental Study on Papermaking Wastewater by Advanced Electrochemical Oxidation Method

2013 ◽  
Vol 726-731 ◽  
pp. 1699-1703
Author(s):  
Lin Lin Huang ◽  
Jun Feng Liu ◽  
Bin Sun ◽  
Nan Zhang ◽  
Yong Qing Tang ◽  
...  
Keyword(s):  
Electrochemical Oxidation ◽  
Current Density ◽  
Treatment Time ◽  
Oxygen Demand ◽  
Treatment Method ◽  
Electrochemical Reactor ◽  
Advanced Treatment ◽  
Processing Unit ◽  
Optimum Reaction ◽  
Papermaking Wastewater

Papermaking wastewater effluent from a biological processing unit was treated by an advanced treatment method-electrochemical oxidation process. The experiments were carried out in an electrochemical reactor using RuO2\SnO2 coated on titanium as anode and stainless steel as cathode. The changes of Chemical Oxygen Demand (COD) reduction and other relative parameters have been determined as a function of treatment time and applied current density. The optimum reaction time and current density was 60min and 5mA/cm2, respectively. Results indicate that as an advanced treatment method, electrochemical oxidation can treat papermaking wastewater to achieve the standard of effluents effectively.

Research on the Treatment of Dyeing Wastewater by Heterogeneous Catalytic Ozonation Process

2011 ◽  
Vol 368-373 ◽  
pp. 3793-3796
Author(s):  
Li Ping Wang ◽  
Yong Jing Mao ◽  
Yu Chuan Guo ◽  
Er Deng Du
Keyword(s):  
High Efficiency ◽  
Removal Rate ◽  
Aeration Rate ◽  
Catalytic Ozonation ◽  
Practical Significance ◽  
Impregnation Method ◽  
Dyeing Wastewater ◽  
Heterogeneous Catalytic ◽  
Novel Catalyst ◽  
Ozonation Process

It is of great practical significance to develop integrated processes with high efficiency, adaptability and stability to treat the dyeing wastewater with the feature of high organic matter, high-color and large ranges in water quality and quantity. In this paper, a novel catalyst MnOx+FexOy/AC was prepared by the impregnation method. The catalyst was used in the heterogeneous catalytic ozonation process to treat the dyeing wastewater. The results showed that the optimal Fe:Mn ratio of catalyst is 1:2. Under the optimized conditions of pH 5, ozone aeration rate 0.2L/min, catalyst dosage 20g and the reaction time 60min, the removal rate of COD, NH3-N, TP, Chromaticity were 81.7%, 90.2%, 93.4%, 99.1%, respectively. The heterogeneous catalytic ozonation is a promising process for the treatment of dyeing wastewater.

scholarly journals Treatment of Tannery Wastewater with Vibratory Shear-Enhanced Processing Membrane Filtration

Separations ◽  
2019 ◽  
Vol 6 (2) ◽  
pp. 20 ◽  
Author(s):  
Anastasios Zouboulis ◽  
Efrosyni Peleka ◽  
Anastasia Ntolia
Keyword(s):  
Vibration Amplitude ◽  
Membrane Filtration ◽  
Suspended Solids ◽  
Removal Rate ◽  
Oxygen Demand ◽  
Treated Wastewater ◽  
Treatment Efficiency ◽  
Membrane Unit ◽  
Membrane Type

The performance of a vibratory shear-enhanced process (VSEP) combined with an appropriate membrane unit for the treatment of simulated or industrial tannery wastewaters was investigated. The fundamental operational and pollution parameters were evaluated, i.e., the membrane type, the applied vibration amplitude, as well as the removal rates (%) of tannins, chemical oxygen demand (COD), Ntotal, turbidity and color. Regarding the system’s treatment efficiency, specific emphasis was given towards the removal of organics (expressed as COD values), suspended solids (SS), conductivity (as an index of dissolved solids’ presence) and total nitrogen. The removal of organic matter in terms of COD exceeded 75% for all the examined cases. The quality of treated wastewater was affected not only by the membrane specific type (i.e., the respective pore diameters), but also by the applied vibration amplitude. Furthermore, an average 50% removal rate, regarding the aforementioned parameters, was observed both for the simulated and the industrial tannery wastewaters during the microfiltration (MF) experiments. That removal rate was further increased up to 85%, when ultrafiltration (UF) was applied, and up to 99% during the Reverse Osmosis (RO) experiments, considering the maximum applied vibration amplitude (31.75 mm).

scholarly journals Fabricating novel PVDF-g-IBMA copolymer hydrophilic ultrafiltration membrane for treating papermaking wastewater with good antifouling property

2021 ◽  
Author(s):  
Yujia Tong ◽  
Wenlong Ding ◽  
Lijian Shi ◽  
Weixing Li
Keyword(s):  
Polyvinylidene Fluoride ◽  
Removal Rate ◽  
Pure Water ◽  
Water Flux ◽  
Oxygen Demand ◽  
Amphiphilic Copolymer ◽  
Ultrafiltration Membrane ◽  
Ultrafiltration Membranes ◽  
Pure Water Flux ◽  
Papermaking Wastewater

Abstract Ultrafiltration membranes are widely used for the treatment of papermaking wastewater. The antifouling performance of polyvinylidene fluoride (PVDF) ultrafiltration membranes can be improved by changing the hydrophilicity. Here, a novel amphiphilic copolymer material, PVDF grafted with N-isobutoxy methacrylamide (PVDF-g-IBMA), was prepared using ultraviolet-induced Cu(II)-mediated reversible deactivation radical polymerization. The amphipathic copolymer was used to prepare ultrafiltration membrane via NIPS. The prepared PVDF-g-IBMA ultrafiltration membrane was estimated using 1H NMR, FT-IR, and DSC. The contact angle, casting viscosity, and the permeation performance of the PVDF-g-IBMA ultrafiltration membrane were also determined. The pure water flux, bovine serum albumin removal rate, and pure water flux recovery rate of the PVDF-g-IBMA ultrafiltration membrane were 432.8 L·m−2·h−1, 88.4%, and 90.8%, respectively. Furthermore, for the treatment of actual papermaking wastewater, the chemical oxygen demand and turbidity removal rates of the membrane were 61.5% and 92.8%, respectively. The PVDF-g-IBMA amphiphilic copolymer ultrafiltration membrane exhibited good hydrophilicity and antifouling properties, indicating its potential for treating papermaking wastewater.

scholarly journals Application of heterogeneous catalytic ozonation process for treatment of high toxic effluent from a pesticide manufacturing plant

2020 ◽  
Vol 7 (2) ◽  
pp. 79-88
Author(s):  
Mina Ghahrchi ◽  
Edris Bazrafshan ◽  
Behruz Adamiyat Badan ◽  
Yousef Dadban Shahamat ◽  
Fariba Gohari
Keyword(s):  
Reaction Time ◽  
Treatment Process ◽  
Catalyst Concentration ◽  
Oxygen Demand ◽  
Catalytic Ozonation ◽  
Cod Removal ◽  
Heterogeneous Catalytic ◽  
Removal Efficiencies ◽  
Ozonation Process ◽  
Maximum Removal

Background: The discharge of untreated wastewater containing toxic and resistant compounds into the environment is a serious threat for ecosystems. Therefore, this study was conducted to evaluate the treatment of poison production factory wastewater using heterogeneous catalytic ozonation process (COP). Methods: Magnetic carbon nanocomposite was used as a catalyst at concentrations of 1, 2, and 4 g/L. Its effect on improving the treatment process was evaluated at reaction time of 30, 60, 90, and 120 minutes. At the end of each experiment, parameters including total organic carbon (TOC), chemical oxygen demand (COD), biological oxygen demand (BOD5 ), pH, electrical conductivity (EC), and turbidity were measured. Results: It was revealed that in single ozonation process (SOP), the maximum removal efficiencies of TOC, COD, and BOD5 were achieved at reaction time of 120 minutes as 56%, 40%, and 11.7%, respectively. By adding the catalyst to the wastewater, the treatment process was improved, so that the maximum removal efficiencies of COD (91%), TOC (73%), and BOD5 (74%) were obtained at catalyst concentration of 4 g/L. Under this condition, BOD5 /COD ratio increased from 0.22 to 0.64. Also, the results of analysis of ozone consumption per each mg of reduced COD showed that its amount sharply decreased from 2.1 mgO3 / mg COD removal in the SOP, to 0.34 mgO3 /mg COD removal in the COP. The results of kinetic reaction analysis also revealed that the rate constant increased from 0.007 to 0.02 min-1. Conclusion: According to the results, it can be concluded that the COP at a catalyst concentration of 4 g/L, by decomposing resistant compounds and increasing the biodegradability, can be used as a suitable pretreatment method for biological processes.

scholarly journals Removal of Phenol From Wastewater by High-Gravity Intensified Heterogeneous Catalytic Ozonation With Activated Carbon

2021 ◽  
Author(s):  
jingwen zhang ◽  
shengjuan shao ◽  
xin ding ◽  
zhixing li ◽  
jiaxin jing ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Removal Rate ◽  
Packed Bed ◽  
Catalytic Ozonation ◽  
High Gravity ◽  
Paramagnetic Resonance ◽  
Heterogeneous Catalytic ◽  
Tertiary Butanol ◽  
Rotating Packed Bed ◽  
Initial Ph

Abstract In this study, the high-gravity technique is used to intensify the heterogeneous catalytic ozonation with activated carbon (AC) as the catalyst for removal of phenol from wastewater in a rotating packed bed (RPB), and the effects of high-gravity factor, inlet O3 concentration, liquid-gas ratio and initial pH on the degradation and mineralization of phenol at room temperature are investigated. It is revealed that the degradation rate of phenol reaches 100% at 10 min and the removal rate of total organic carbon (TOC) reaches 91% at 40 min under the conditions of high-gravity factor β=40, inlet O3 concentration =90 mg·L-1, liquid flow rate =80 L·h-1 and initial pH=11. Compared with the bubbling reactor (BR)/O3/AC and RPB/O3 systems, the mineralization rate of phenol by the RPB/O3/AC system is increased by 24.78% and 34.77%, respectively. Free radical quenching experiments are performed using tertiary butanol (TBA) and benzoquinone(BQ) as scavengers of ·OH and O2·−, respectively. It is shown that the degradation and mineralization of phenol are respectively attributed to the direct ozonation and the indirect oxidation by ·OH generated from the decomposition of O3 adsorbed on AC surface. •OH and O2•− are also detected by electron paramagnetic resonance (EPR). Thus, it is concluded that AC-catalyzed ozonation and high gravity technique had a synergistic effect on •OH initiation, which in turn can significantly improve the degradation and mineralization of organic wastewater.

scholarly journals On-line chemical oxygen demand estimation models for the photoelectrocatalytic oxidation advanced treatment of papermaking wastewater

2018 ◽  
Vol 78 (2) ◽  
pp. 310-319 ◽  
Author(s):  
Wenhao Shen ◽  
Feini Huang ◽  
Xuewen Zhang ◽  
Yuefei Zhu ◽  
Xiaoquan Chen ◽  
...  
Keyword(s):  
Neural Network ◽  
Chemical Oxygen Demand ◽  
Batch Reactor ◽  
Estimation Method ◽  
Oxygen Demand ◽  
Paper Mill ◽  
Advanced Treatment ◽  
On Line ◽  
Line Analysis ◽  
Papermaking Wastewater

Abstract Chemical oxygen demand (COD), an important indicative measure of the amount of oxidizable pollutants in wastewater, is often analyzed off-line due to the expensive sensor required for on-line analysis. However, its off-line analysis is time-consuming. An on-line COD estimation method was developed with photoelectrocatalytic (PEC) technology. Based on the on-line data of the oxidation–reduction potential (ORP), dissolved oxygen (DO) and pH of wastewater, four different artificial neural network methods were applied to develop working models for COD estimation. Six different batches of sequence batch reactor (SBR) effluent from a paper mill were treated with PEC oxidation for 90 minutes, and 546 data points were collected from the on-line measurements of ORP, DO and pH, and the off-line COD analysis. After having training and validation with 75% and 25% of data, and evaluation with four statistical criteria (R2, RMSE, MAE and MAPE), the estimation results indicated that the developed radial basis neural network (RBNN) model demonstrated the highest precision. Subsequently, the application of the RBNN model to a new batch of SBR effluent from the paper mill revealed that the RBNN model was acceptable for COD estimation during the PEC advanced treatment process of papermaking wastewater, which implied its possible application in the future.

Sign in / Sign up

Export Citation Format

Share Document