Influence of Operating Conditions on the Persulfate Oxidation of Textile Waste Water at Ambient Temperature

2015 ◽  
Vol 802 ◽  
pp. 454-459 ◽  
Author(s):  
Fagbenro Oluwakemi Kehinde ◽  
Hamidi Abdul Aziz
Keyword(s):  
Contact Time ◽  
Suspended Solids ◽  
Oxygen Demand ◽  
Textile Wastewater ◽  
Operating Conditions ◽  
Molar Ratio ◽  
Solution Ph ◽  
Persulfate Oxidation ◽  
Ambient Temperatures ◽  
Textile Waste Water

At the ambient temperatures, the influence of operating conditions on persulfate (S2O8) oxidation of real textile wastewater was investigated for the removal of color, suspended solids (SS) and chemical oxygen demand (COD). The effects of oxidant dosage, initial solution pH and contact time were studied in a series of batch experiments using persulfate (PS) oxidant as sodium persulfate. Oxidant dose was defined by an oxidant/contaminant (PS/COD) molar ratio, varied from 1/1-10/1. Although parameter removals increased with the oxidant dose, especially for color and SS, a PS/COD molar ratio of 4/1 (6720mg/L) was adopted in a bid to use fewer chemicals. The pH was varied from 2-11, with pH of between 2 and 3 being the optimum. At 360minutes contact time, the removals of color, SS and COD were 84%; 71% and 32% respectively. Although relatively effective, especially for color removal, results show that the reactions might have been inhibited at ambient temperatures as shown by the particularly low removal of COD.

scholarly journals Synthesis of Nd-doped ZSM-5 and its application to treating slightly polluted water

2017 ◽  
Vol 8 (1) ◽  
pp. 86-93
Author(s):  
Mang Lu ◽  
Lin He ◽  
Yue Cheng
Keyword(s):  
Contact Time ◽  
Oxygen Demand ◽  
Raw Material ◽  
Molar Ratio ◽  
Polluted Water ◽  
Solution Ph ◽  
Experimental Conditions ◽  
Factors Influencing ◽  
Orthogonal Experiments ◽  
Removal Efficiencies

Abstract In this study, ZSM-5 zeolite was synthesized using diatomaceous mud as the raw material, and then doped with different amounts of Nd2O3. The orthogonal experiments were performed to investigate the influence of Nd:Si molar ratio, zeolite dosage, contact time, solution pH and temperature on the removal of humic acid (HA). The removal of HA was comprehensively evaluated by chemical oxygen demand (COD), UV254 and UV410 of the solution. The results demonstrate that solution pH and zeolite dosage are the two most important factors influencing HA adsorption. The optimum experimental conditions were determined to be: 35 °C, Nd:Si molar ratio of 1:100, 2.0 g/L zeolite, pH 4 and 50 min contact time. Under these conditions, the removal efficiencies of UV254, UV410 and COD are 82.70%, 76.00% and 82.10%, respectively, corresponding to a comprehensive removal of 81.02%.

scholarly journals Red Mud-Based Polyaluminum Ferric Chloride Flocculant: Preparation, Characterization and Flocculation Performance

2021 ◽  
Author(s):  
Yong Cheng ◽  
Longjun Xu ◽  
Chenglun Liu ◽  
Zao Jiang ◽  
Qiyuan Zhang ◽  
...  
Keyword(s):  
Red Mud ◽  
High Efficiency ◽  
Low Cost ◽  
Oxygen Demand ◽  
Industrial Applications ◽  
Iron Chloride ◽  
Raw Material ◽  
Molar Ratio ◽  
Polymerization Temperature ◽  
Solution Ph

Abstract In this work, red mud was used as raw material to extract Al and Fe with hydrochloric acid. The high-efficiency polyaluminum iron chloride (PAFC) flocculant was prepared via adjusting the pH of the leaching solution, the molar ratio of aluminum and iron, and the polymerization temperature. The effect of synthesis and flocculation conditions on the flocculation performance of aged landfill leachate was investigated. The results confirmed that the PAFC prepared at the polymerization pH of 2.5, the Al/Fe molar ratio of 8, and the polymerization temperature of 70 °C had the optimum flocculation effect. The flocculation consequences of PAFC and commercial polyaluminum iron chloride flocculant (CPAFC) under different flocculation conditions were compared. The chemical oxygen demand (COD), UV254, chroma and settlement height of PAFC at flocculant concentration of 60 g/L and solution pH of 6 were 72.2%, 79.2%, 82.9% and 9.5 cm (within 90 min), respectively. PAFC has excellent flocculation performance and can be used as a simple, potentially low-cost wastewater treatment agent in industrial applications.

scholarly journals Treatment of textile wastewater using a novel electrocoagulation reactor design

2018 ◽  
Vol 20 (3) ◽  
pp. 449-457
Keyword(s):  
Wastewater Treatment ◽  
Rotation Speed ◽  
Removal Rate ◽  
Operating Time ◽  
Oxygen Demand ◽  
Textile Wastewater ◽  
Total Suspended Solid ◽  
Operating Conditions ◽  
Conventional Model ◽  
Textile Wastewater Treatment

<p>This study explored the best-operating conditions for a novel electrocoagulation (EC) reactor with the rotating anode for textile wastewater treatment. The influence of operating parameters like inter-electrode distance (IED), current density (CD), temperature, pH, operating time (RT), and rotation speed on the removal efficiency of the contaminant was studied. A comparative study was done using conventional model with static electrodes in two phases under same textile wastewater The findings revealed that the optimal conditions for textile wastewater treatment were attained at RT = 10 min, CD = 4 mA/cm2, rotation speed = 150 rpm, temperature = 25oC, IED = 1cm, and pH = 4.57. The removal efficiencies of colour, biological oxygen demand (BOD), turbidity, chemical oxygen demand (COD), and total suspended solid (TSS) were 98.50%, 95.55%, 96%, 98% and 97.10% within the first 10 min of the reaction. The results of the experiment reveal that the newly designed reactor incorporated with cathode rings and rotated anode impellers provide a superior treatment efficiency within a short reaction time. The novel EC reactor with a rotating anode significantly enhanced textile wastewater treatment compared to the conventional model. The values of adsorption and passivation resistance validated the pollutants removal rate.</p>

scholarly journals CuO Coated Electrochemically Generated Textile Wastewater Sludge and CuO Coated GAC as Potential Nano-adsorbents for Color Removal from Real Textile Wastewater

2018 ◽  
Vol 34 (4) ◽  
pp. 2144-2151
Author(s):  
Srikantha H, S. Mahesh ◽  
Sahana M
Keyword(s):  
Contact Time ◽  
Cell Voltage ◽  
Textile Wastewater ◽  
Xrd Analysis ◽  
Operating Conditions ◽  
Wastewater Sludge ◽  
Color Removal ◽  
Batch Adsorption ◽  
Batch Mode ◽  
Nano Adsorbent

A laboratory scale setup was used to remove color from real textile wastewater (TWW) using nano CuO coated electrochemically generated sludge and nano CuO coated GAC. ECC studies were conducted in batch-mode to generate sludge treating real TWW using pre-optimized 4SS electrodes using a 1.5L reactor operated at cell voltage of 18V and current density 180A/m2 at an agitation speed of 500rpm for 60min electrolysis time. SEM, FTIR and XRD analysis confirmed CuO material successfully coated/decorated on electrochemically generated sludge of size ~0.3-0.5mm and GAC of size ~0.5mm. To check the color removal efficiencies from TWW the batch adsorption studies were conducted for adsorbent dose, stirring time and pH. The optimal operating conditions achieved at pH-4, dose of 0.6g/L and 30min contact time for CuO-sludge nano-adsorbent achieving 50-55% color removal. Similarly, for CuO-GAC nano-adsorbent the optimal conditions obtained at pH-4, 0.5 g/L dose and 20min contact time achieving ~100% removal.

scholarly journals Optimized Pretreatment of Non-Thermal Plasma for Advanced Sewage Oxidation

2020 ◽  
Vol 17 (20) ◽  
pp. 7694
Author(s):  
Hee-Jun Kim ◽  
Chan-Hee Won ◽  
Hyun-Woo Kim
Keyword(s):  
Thermal Plasma ◽  
Contact Time ◽  
Oxygen Demand ◽  
Advanced Oxidation ◽  
Operating Conditions ◽  
Efficient Operation ◽  
Higher Temperature ◽  
Non Thermal Plasma ◽  
Optimal Efficiency ◽  
Optimized Conditions

This study investigates how the non-thermal plasma (NTP) process leads to advanced oxidation of sewage using response surface methodology. For environmentally viable and efficient operation of the NTP process, temperature and contact time were selected as two important independent variables. Their impacts on the performance were tested following an experimental design to figure out optimal operating conditions. Based on obtained treatment efficiency, statistically optimized conditions were derived by using an approach adapting the central composite design. Results show that coupling 40 °C of temperature and 4 h of contact time demonstrate optimal performance for total chemical oxygen demand (TCOD, 59%) and total suspended solids (85%), respectively. This implies that NTP may present efficient particulate destruction leading to organic solids dissolution. Statistical analysis reveals that the contact time shows more significant dependency than the temperature on the advanced oxidation of TCOD, possibly due to dissolved organic material. For total nitrogen removal, on the contrary, the optimal efficiency was strongly related to the higher temperature (~68 °C). This work provides an inroad to considering how NTP can optimally contribute to better oxidation of multiple pollutants.

Fenton-Like Oxidation of Refractory Chemical Wastewater Using Pyrite

2012 ◽  
Vol 518-523 ◽  
pp. 2518-2525 ◽  
Author(s):  
Yong Feng ◽  
De Li Wu ◽  
Dong Duan ◽  
Ming Ma Lu
Keyword(s):  
Ph Value ◽  
Removal Rate ◽  
Oxygen Demand ◽  
Textile Wastewater ◽  
Solution Ph ◽  
Natural Iron ◽  
Fenton Reagents ◽  
Value Range ◽  
Cod Removal Rate ◽  
High Level

Fenton-like reaction technologies are attracting considerable attention due to the high oxidizing ability, especially in the treatment of refractory chemical contaminants. However, some disadvantages in traditional Fenton reagents limited its wide application. In this study, pyrite, a natural iron bearing mineral, was used as a new kind of Fenton-like catalyst in the treatment of textile wastewater. The catalytic activity of pyrite and the parameters influencing the removal of Chemical Oxygen Demand (COD) and Biochemical Oxygen Demand (BOD5), such as pyrite dosage, H2O2 concentration, pH, and suspended solids (SS) had been systematically examined. Results showed that pyrite exhibited a high catalytic reactivity over a wide pH value range. At the optimal conditions, a COD removal rate of 70% and an increase in the mass ratio of BOD5/COD (B/C) from 0.25 to 0.56 were achieved in the presence of 9.7 mM H2O2 and 10 g/L pyrite at initial solution pH value of 9.0. And what’s more, a rapid decrease in solution pH and a high level of iron were observed when pyrite was added to the wastewater, probably due to the oxidative dissolution of pyrite. Consequently, Apart from the heterogeneous process, it was found that a homogeneous interaction between ferrous iron and H2O2 in a classical Haber-Weiss mechanism was also occurred. The wonderful reactivity of pyrite makes it be used as catalyst for the oxidative technology to treat the original wastewater without the need to pre-adjust the solution pH.

Removal of Suspended Solids, Chemical Oxygen Demand and Color from Domestic Wastewater Using Sago Starch as Coagulant

2015 ◽  
Vol 802 ◽  
pp. 519-524
Author(s):  
Wan Izatul Saadiah Wan Kamar ◽  
Hamidi Abdul Aziz ◽  
Siti Fatihah Ramli
Keyword(s):  
Chemical Oxygen Demand ◽  
Suspended Solids ◽  
Sewage Treatment Plant ◽  
Oxygen Demand ◽  
Domestic Wastewater ◽  
Operating Conditions ◽  
Wastewater Sample ◽  
Sago Starch ◽  
Rapid Mixing ◽  
Slow Mixing

Sago starch has been widely used in industrial fields, especially in food, non-food, and animal feed biotechnology. Malaysia is one of the highest local sources of sago starch. The alternative use of sago starch as a coagulant for domestic wastewater treatment was investigated in this study. The wastewater sample was collected from the Juru Regional Sewage Treatment Plant in Juru, Penang. The studied parameters include the chemical oxygen demand (COD), suspended solids, and color. Standard jar test procedures were conducted. The initial operating conditions were 200 rpm for 3 min of rapid mixing, 40 rpm for 30 min of slow mixing, and 30 min of settling. The optimum conditions included a pH of 7 and dosage of 2000 mg/L, with rapid mixing at 100 rpm for 1 min, slow mixing at 20 rpm for 30 min, and 18 min of settling. The removal rate of COD and color at these conditions was 70%. Simultaneously, 82% of SS was also removed. The results indicated that sago starch has good potential to treat domestic wastewater; the coagulant may also efficiently treat other types of wastewater.

scholarly journals Electrocoagulación en el agua de proceso de una Industria de alimentos

2019 ◽  
pp. 48-52
Author(s):  
María Guadalupe Martin del Campo-Sanchez ◽  
José Luis Escobar-Gonzalez
Keyword(s):  
Wastewater Treatment ◽  
Chemical Oxygen Demand ◽  
Contact Time ◽  
Suspended Solids ◽  
Oxygen Demand ◽  
Total Suspended Solids ◽  
Statistical Test ◽  
Parallel Plates ◽  
Cost Of Treatment ◽  
Approximate Cost

The main objective was to develop a wastewater treatment system by means of the electrocoagulation method according to the parameters of Chemical Oxygen Demand (COD) and Total Suspended Solids (SST). The results obtained were that at a pH of 6 and 7 with a contact time of 30 minutes, the highest percentage of removal of SST (98%) and COD (90%) was obtained. Once the conductor was selected, tests were carried out at different pH (6, 7 and 8) with contact times of 15, 30 and 45 minutes each, at 12 V and 0.4 A. A Multifactorial ANOVA statistical test was performed to determine if there were significant differences between the treatments. Once the results were evaluated, a prototype of approximately 38 L was designed with parallel plates with results of removal of SST of 93% and COD of 66%. The approximate cost of treatment per cubic meter is $ 35

Photo-assisted electrochemical degradation of real textile wastewater

2010 ◽  
Vol 61 (2) ◽  
pp. 491-498 ◽  
Author(s):  
P. A. Alves ◽  
G. R. P. Malpass ◽  
H. D. Johansen ◽  
E. B. Azevedo ◽  
L. M. Gomes ◽  
...  
Keyword(s):  
Supporting Electrolyte ◽  
Oxygen Demand ◽  
Textile Wastewater ◽  
Operating Conditions ◽  
Cod Removal ◽  
Constant Current ◽  
Electrochemical Degradation ◽  
Figures Of Merit ◽  
Before And After ◽  
Initial Ph

In the present study, photo-assisted electrochemical degradation of real textile wastewater was performed. Degradation assays were performed at constant current (40 mA cm−2) in a combined electro/photochemical flow-cell using a Ti/Ru0.3Ti0.7O2 DSA® type electrode. The results show that the method is capable of removing color and chemical oxygen demand (COD) from the effluent. Additionally, the effect of initial pH and type of supporting electrolyte (Na2SO4 or NaCl) was investigated. The principal figures of merit used in this study were COD removal and color removal (605 nm). The results show that up to 72% color and up to 59% COD removal in 120 min is possible under the operating conditions employed. Studies of the phytotoxicity of the wastewater before and after the photo-assisted degradation assays are also presented and the results demonstrate that the toxicity of the effluent is dependent on the length of electrolysis time and the treatment procedure employed.

Sewage sludge solubilization by high-pressure homogenization

2013 ◽  
Vol 67 (11) ◽  
pp. 2399-2405 ◽  
Author(s):  
Yuxuan Zhang ◽  
Panyue Zhang ◽  
Jianbin Guo ◽  
Weifang Ma ◽  
Wei Fang ◽  
...  
Keyword(s):  
High Pressure ◽  
Energy Efficient ◽  
Suspended Solids ◽  
Oxygen Demand ◽  
Operating Conditions ◽  
High Pressure Homogenization ◽  
Sludge Sample ◽  
Cycle Number ◽  
Soluble Chemical Oxygen Demand ◽  
Solids Content

The behavior of sludge solubilization using high-pressure homogenization (HPH) treatment was examined by investigating the sludge solid reduction and organics solubilization. The sludge volatile suspended solids (VSS) decreased from 10.58 to 6.67 g/L for the sludge sample with a total solids content (TS) of 1.49% after HPH treatment at a homogenization pressure of 80 MPa with four homogenization cycles; total suspended solids (TSS) correspondingly decreased from 14.26 to 9.91 g/L. About 86.15% of the TSS reduction was attributed to the VSS reduction. The increase of homogenization pressure from 20 to 80 MPa or homogenization cycle number from 1 to 4 was favorable to the sludge organics solubilization, and the protein and polysaccharide solubilization linearly increased with the soluble chemical oxygen demand (SCOD) solubilization. More proteins were solubilized than polysaccharides. The linear relationship between SCOD solubilization and VSS reduction had no significant change under different homogenization pressures, homogenization cycles and sludge solid contents. The SCOD of 1.65 g/L was solubilized for the VSS reduction of 1.00 g/L for the three experimental sludge samples with a TS of 1.00, 1.49 and 2.48% under all HPH operating conditions. The energy efficiency results showed that the HPH treatment at a homogenization pressure of 30 MPa with a single homogenization cycle for the sludge sample with a TS of 2.48% was the most energy efficient.

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