scholarly journals Treatment of leachate by combining PAC and UV/O3 processes

2012 ◽  
Vol 3 (1) ◽  
pp. 38-42 ◽  
Author(s):  
Huu Tap Van ◽  
Van Tuyen Trinh ◽  
Xuan Hien Dang
Keyword(s):  
Reaction Time ◽  
Removal Efficiency ◽  
Ph Value ◽  
Oxygen Demand ◽  
Experimental Investigations ◽  
Colour Removal ◽  
Treatment Stage ◽  
Pre Treatment ◽  
Optimal Reaction

The landfill leachate is commonly treated for non-biodegradable organic matters, ammonia and colour. Experimental investigations using polyaluminium chlorite (PAC) and UV/O3 have been conducted for the determination of optimal pH value, reaction time and PAC concentration for the removal of chemical oxygen demand (COD) and colour. In pre-treatment coagulation stages, the highest COD and colour removal efficiencies were observed at the concentration of PAC ≥ 3,000 mglG1 and pH values between 7 and 8. However, these experiments also indicated significant removal efficiency for PAC starting with concentrations of 1,500 mglG1. The efficiency of COD and colour removal were approximately 30% and 70%, respectively. Similar efficiencies have been observed also during the second treatment stage where UV/O3 processes were used to treat coagulated leachate. After UV/O3 application, the pH of leachate reached the optimum value of 7.5 whereas the highest COD and colour removal efficiency was 55% and 72%, respectively, and the optimal reaction time was achieved after 80 min. Nước rỉ rác sinh ra từ bãi chôn lấp chất thải rắn cần được xử lý các thành phần chất hữu cơ khó phân hủy sinh học, xử lí amoni và độ màu. Một số kết quả thử nghiệm về xử lý COD và màu của nước rỉ rác bằng việc sử dụng phương pháp keo tụ vớiPAC và quá trình UV/O3 đã được thực hiện cùng với việc xác định các giá trị pH tối ưu, thời gian phản ứng và nồng độ PAC tối ưu. Hiệu suất xử lý cao nhất đạt được khi nồng độ của PAC ≥ 3.000 mg/l, pH trong khoảng từ 7 đển 8 trong giai đoạn tiền xửlý. Tuy nhiên, hiệu quả loại bỏ COD và màu bắt đầu tăng rõ khi nồng độ PAC từ 1.500 mg/l trở lên. Hiệu quả loại bỏ COD và màu tương ứng là khoảng 30% và 70%. Các giá trị pH này phù hợp cho quá trình phản ứng UV/O3 được sử dụng sau giai đoạn keo tụ. Sau quá trình xử lý bằng hệ UV/O3, pH của nước rỉ rác tối ưu được xác định là 7,5 (hiệu suất xử lý COD và màu cao nhất tương ứng là 55% và 72%), thời gian phản ứng tối ưu là 80 phút.

scholarly journals Experimental Study on the Treatment of 1, 4 butanediol Mixed Wastewater by Ferro-carbon Micro-electrolysis

2019 ◽  
Vol 83 ◽  
pp. 01015
Author(s):  
Jie Lei ◽  
Xiaodong Zhang ◽  
Zhenglin Zhou ◽  
Shaohui Fan ◽  
Bo Jiang ◽  
...  
Keyword(s):  
Reaction Time ◽  
Removal Efficiency ◽  
Activated Carbons ◽  
Ph Value ◽  
Influencing Factor ◽  
Oxygen Demand ◽  
Carbon Powder ◽  
Treatment Rate ◽  
Surface Method ◽  
Influence Degree

The mixed wastewater of 1, 4 butanediol was tested with iron filings and carbon powder as catalyst by aeration to provide oxygen. The effects of carbon powder, pH value and reaction time on wastewater treatment were studied. The optimal experimental condition was that the mesh number of activated carbons was 20, the pH value was 5, the reaction time was 30min, and the Chemical Oxygen Demand (COD) removal efficiency reached 36.2%. At the same time, The response surface method was used to analyze and optimize the experimental results, and the relation formula of each influencing factor on removal efficiency was established, and the order of influence degree of each factor on removal efficiency (pH> activated carbon mesh number > reaction time) was obtained, in which pH had the greatest influence on the treatment rate of ferro-carbon micro-electrolysis treatment of 1, 4-butanediol wastewater.

scholarly journals Study on Chromaticity Removal from Mineral Processing Wastewater with Salicylic Hydroxamic Acid by Granular Activated Carbon Catalyzed Ozonation

Minerals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 359
Author(s):  
Liping Zhang ◽  
Shengnian Wu ◽  
Nan Zhang ◽  
Ruihan Yao ◽  
Eryong Wu
Keyword(s):  
Activated Carbon ◽  
Reaction Time ◽  
Hydroxamic Acid ◽  
Ph Value ◽  
Oxygen Demand ◽  
Granular Activated Carbon ◽  
Mineral Processing ◽  
Ultraviolet Absorption Spectrum ◽  
Experimental Conditions ◽  
Removal Ratio

Salicylic hydroxamic acid is a novel flotation reagent used in mineral processing. However, it impacts the flotation wastewater leaving behind high chromaticity which limits its reuse and affects discharge for mining enterprises. This study researched ozonation catalyzed by the granular activated carbon (GAC) method to treat the chromaticity of the simulated mineral processing wastewater with salicylic hydroxamic acid. The effects of pH value, ozone (O3) concentration, GAC dosage, and reaction time on chromaticity and chemical oxygen demand (CODCr) removal were discussed. The results of individual ozonation experiments showed that the chromaticity removal ratio reached 79% and the effluent chromaticity exceeded the requirement of reuse and discharge when the optimal experimental conditions were pH value 3, ozone concentration 6 mg/L, and reaction time 40 min. The orthogonal experimental results of catalytic ozonation with GAC on chromaticity removal explained that the chromaticity removal ratio could reach 96.36% and the chromaticity of effluent was only 20 when the optimal level of experimental parameters was pH value 2.87, O3 concentration 6 mg/L, GAC dosage 0.06 g/L, reaction time 60 min respectively. The degradation pathway of salicylic hydroxamic acid by ozonation was also considered based on an analysis with ultraviolet absorption spectrum and high-performance liquid chromatography (HPLC).

Removal of phenol from steel wastewater by combined electrocoagulation with photo-Fenton

2018 ◽  
Vol 78 (6) ◽  
pp. 1260-1267 ◽  
Author(s):  
Mohammad Malakootian ◽  
Mohammad Reza Heidari
Keyword(s):  
Reaction Time ◽  
Removal Efficiency ◽  
Current Density ◽  
Steel Industry ◽  
High Efficiency ◽  
Oxygen Demand ◽  
Optimal Conditions ◽  
Suitable Alternative ◽  
Steel Mills ◽  
Real Wastewater

Abstract Phenol and its derivatives are available in various industries such as refineries, coking plants, steel mills, drugs, pesticides, paints, plastics, explosives and herbicides industries. This substance is carcinogenic and highly toxic to humans. The purpose of the study was to investigate the removal of phenol from wastewater of the steel industry using the electrocoagulation–photo-Fenton (EC-PF) process. Phenol and chemical oxygen demand (COD) removal efficiency were investigated using the parameters pH, Fe2+/H2O2, reaction time and current density. The highest removal efficiency rates of phenol and COD were 100 and 98%, respectively, for real wastewater under optimal conditions of pH = 4, current density = 1.5 mA/cm2, Fe2+/H2O2 = 1.5 and reaction time of 25 min. Combination of the two effective methods for the removal of phenol and COD, photocatalytic electrocoagulation photo-Fenton process is a suitable alternative for the removal of organic pollutants in industry wastewater because of the low consumption of chemicals, absence of sludge and other side products, and its high efficiency.

Optimizing determination of plasma albumin by the bromcresol green dye-binding method.

1981 ◽  
Vol 27 (1) ◽  
pp. 144-146 ◽  
Author(s):  
W S Robertson
Keyword(s):  
Reaction Time ◽  
Linear Regression ◽  
Human Plasma ◽  
Protein Composition ◽  
Improved Method ◽  
Reaction Conditions ◽  
Plasma Albumin ◽  
Optimal Reaction ◽  
Bromcresol Green

Abstract Some modifications of the conditions of the reaction between plasma and bromcresol green have led to an improved method for determination of plasma albumin with the Vickers M300 multichannel analyzer. Dye concentration and reaction time are the factors principally influencing method specificity, but variable protein composition of human plasma also affects it, so that optimal reaction conditions vary from specimen to specimen. Thus a compromise must be reached such that the best conditions for determining plasma albumin over a range of different protein concentrations are achieved. In the proposed method for the Vickers M300 a reaction time of 12 s (the minimum possible) is used. Comparison with "rocket" immunoelectrophoresis gave the following linear regression: y = 10 + 0.79 x (n = 91; r = 0.96).

scholarly journals Continuous flow electrocoagulation system for the treatment of coir industry wastewater

2021 ◽  
Author(s):  
Ayyappan U ◽  
Indu M.S ◽  
Adithya G Murickan ◽  
Balagopal J ◽  
Arun S Kumar ◽  
...  
Keyword(s):  
Removal Efficiency ◽  
Continuous Flow ◽  
Electrolyte Concentration ◽  
Oxygen Demand ◽  
Synthetic Dyes ◽  
Operational Parameters ◽  
Colour Removal ◽  
Chemical Reagents ◽  
Secondary Pollutants ◽  
Industry Wastewater

Coir industry, a prominent industry in Kerala, uses huge amount of water and chemical reagents for its functioning. The effluent from these industries has high BOD, COD, toxic chemicals, oils and grease etc. Of the various pollutants, synthetic dyes are the most concerning. Electrocoagulation has advantages over other systems, as it doesn’t produce any secondary pollutants. In this study, a continuous flow electrocoagulation reactor is designed and operational parameters like flow rate, voltage, pH, electrolyte concentration, dye concentration and electrode orientation are optimized. The influence of these parameters are assessed by measuring colour removal efficiency (CRE) and chemical oxygen demand (COD). The optimum flow, voltage, electrolyte concentration, pH and electrode orientation were 1000 mL/hr., 8V, 1000 mg/L, 7 and parallel respectively. The optimized parameters were used for performance evaluation of the system in treating coir industry wastewater. Under these optimized conditions, colour removal efficiency, turbidity, pH, COD removal efficiency and BOD removal efficiency for the treated coir industry wastewater was found as 92.17%, 25 NTU, 8.7, 95.49%, and 92.20% respectively.

scholarly journals Feasibility Studies on Treatment of Household Greywater Using Phytoremediation Plants

2021 ◽  
Author(s):  
Neetha Delphin Mary Kulandaiswamy ◽  
Muralimohan Nithyanandam
Keyword(s):  
Electrical Conductivity ◽  
Removal Efficiency ◽  
Ph Value ◽  
Oxygen Demand ◽  
Cyperus Rotundus ◽  
Treatment System ◽  
World Health ◽  
Residual Chlorine ◽  
Typha Angustifolia ◽  
Guideline Values

Abstract Recycling and reusing of wastewater acquired high priority among the research community to meet the ever-increasing demand for groundwater, and to tackle water scarcity in every country. In this scenario, a grey water treatment system is developed with a vertical flow wetland construction tank (VFWCT)with sand, gravel and silex as media combined with phytoremediation technology using plants like Cyperus rotundus, Canna indica, Typha angustifolia, Cyperus pangorei, and Phragmites australis. The assessment parameters like color, odor, temperature, pH, electrical conductivity, free residual chlorine, Total Dissolved Solids (TDS), chloride, Sulphate, Total Suspended Solids (TSS),oil & grease, Sulphide,Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Nitrate Nitrogen, E.coli and Salmonella are used to substantiate the performance of proposed greywater treatment system. Simulation outcomes showed that most of the guideline values of the effluent are notably lower compared to the influent. The experimentation also focused on finding the best plant as Typha angustifolia for greywater treatment in the VFWCT. The plant’s rapid growth and the removal efficiency parameters of the plant with regard to the contaminants present in the greywater was highly notable. The removal efficiency was 56.56% and 50.25% for BOD5 and COD, the solids content TSS and TDS was 68% and 64.4%. The salt Cl− and Na+ removal efficiencies are 63.4% and 81.39% respectively. Majority of the parameters like pH value, Electrical conductivity, odor and TDS are higher than the groundwater aquifers, but falls within the world health organization safety limits.

scholarly journals Electrochemical Degradation of Crystal Violet Using Ti/Pt/SnO2 Electrode

2021 ◽  
Vol 11 (18) ◽  
pp. 8401
Author(s):  
Rachid El Brychy ◽  
Mohamed Moutie Rguiti ◽  
Nadia Rhazzane ◽  
Moulay Driss Mellaoui ◽  
Khalid Abbiche ◽  
...  
Keyword(s):  
Removal Efficiency ◽  
Crystal Violet ◽  
Current Density ◽  
Ph Value ◽  
Supporting Electrolyte ◽  
Chloride Concentration ◽  
Oxygen Demand ◽  
Electrochemical Treatment ◽  
Electrochemical Process ◽  
Initial Ph

Today, organic wastes (paints, pigments, etc.) are considered to be a major concern for the pollution of aqueous environments. Therefore, it is essential to find new methods to solve this problem. This research was conducted to study the use of electrochemical processes to remove organic pollutants (e.g., crystal violet (CV)) from aqueous solutions. The galvanostatic electrolysis of CV by the use of Ti/Pt/SnO2 anode, were conducted in an electrochemical cell with 100 mL of solution using Na2SO4 and NaCl as supporting electrolyte, the effect of the important electrochemical parameters: current density (20–60 mA cm−2), CV concentration (10–50 mg L−1), sodium chloride concentration (0.01–0.1 g L−1) and initial pH (2 to 10) on the efficiency of the electrochemical process was evaluated and optimized. The electrochemical treatment process of CV was monitored by the UV-visible spectrometry and the chemical oxygen demand (COD). After only 120 min, in a 0.01mol L−1 NaCl solution with a current density of 50 mA cm−2 and a pH value of 7 containing 10 mg L−1 CV, the CV removal efficiency can reach 100%, the COD removal efficiency is up to 80%. The process can therefore be considered as a suitable process for removing CV from coloured wastewater in the textile industries.

Removal of Phosphate from Aqueous Solution by Using Red Mud

2011 ◽  
Vol 291-294 ◽  
pp. 1804-1807 ◽  
Author(s):  
Xin Feng Zhu ◽  
Hong Ye Liu ◽  
Peng Hui Shi ◽  
Jun Feng Wu ◽  
Yi Fei Guo
Keyword(s):  
Aqueous Solution ◽  
Reaction Time ◽  
Removal Efficiency ◽  
Red Mud ◽  
Phosphate Concentration ◽  
Phosphate Removal ◽  
Batch Experiments ◽  
Reaction Conditions ◽  
Optimal Reaction

Red mud has been used to develop effective adsorbents to remove phosphate from aqueous solution. The effects of different dosage, pH of solution and reaction time on adsorption have been examined in batch experiments. It was found that red mud samples show higher removal efficiency for phosphate. The results showed that phosphate removal efficiency was found to be 97 % with optimal reaction conditions initial phosphate concentration 100mg L−1, red mud dosage 10g L−1, pH 2.0, respectively. The phosphate removal efficiency of the red mud adsorbents decreases with increase of pH.

scholarly journals Automotive fleet repair facility wastewater treatment using air/ZVI and air/ZVI/H2O2 processes

2017 ◽  
Vol 43 (3) ◽  
pp. 24-31 ◽  
Author(s):  
Jan Paweł Bogacki ◽  
Hussein Al-Hazmi
Keyword(s):  
Wastewater Treatment ◽  
Removal Efficiency ◽  
Treatment Effectiveness ◽  
Ph Value ◽  
Oxygen Demand ◽  
Cod Removal ◽  
Process Time ◽  
Process Conditions ◽  
Cod Removal Efficiency ◽  
Repair Facility

AbstractAdvanced automotive fleet repair facility wastewater treatment was investigated with Zero-Valent Iron/Hydrogen Peroxide (Air/ZVI/H2O2) process for different process parameters: ZVI and H2O2doses, time, pH. The highest Chemical Oxygen Demand (COD) removal efficiency, 76%, was achieved for ZVI/H2O2doses 4000/1900 mg/L, 120 min process time, pH 3.0. COD decreased from 933 to 227 mg/L. In optimal process conditions odor and color were also completely removed. COD removal efficiency was increasing with ZVI dose. Change pH value below and over 3.0 causes a rapid decrease in the treatment effectiveness. The Air/ZVI/H2O2process kinetics can be described as d[COD]/dt = −a [COD]tm, where ‘t’ corresponds with time and ‘a’ and ‘m’ are constants that depend on the initial reagent concentrations. H2O2influence on process effect was assessed. COD removal could be up to 40% (560 mg/L) for Air/ZVI process. The FeCl3coagulation effect was also evaluated. The best coagulation results were obtained for 700 mg/L Fe3+dose, that was slightly higher than dissolved Fe used in ZVI/H2O2process. COD was decreased to 509 mg/L.

The Preparation Technique of Nanometer Molybdenum Trioxide by Hydrothermal Synthesis

2011 ◽  
Vol 117-119 ◽  
pp. 807-810
Author(s):  
Ji Wen Li ◽  
Yan Hua Ma ◽  
Fang Fang Gong ◽  
Guo Shang Zhang ◽  
Liu Jie Xu ◽  
...  
Keyword(s):  
Reaction Time ◽  
Hydrothermal Synthesis ◽  
Reaction Temperature ◽  
Molybdenum Trioxide ◽  
Ph Value ◽  
Ultrafine Particle ◽  
Preparation Technique ◽  
Optimum Ph ◽  
Optimum Reaction ◽  
Optimal Reaction

The technique of hydrothermal synthesis is used to prepare nanometer molybdenum trioxide through controlling the parameters such as the acidification condition, the reaction temperature, the reaction time and so on. The technique is under high temperature and high pressure by water as the solvent. Synthesized molybdenum trioxide powder is characterized by XRD, SEM, and HRTEM. The optimal reaction time is 40h, the optimum reaction temperature is 170°C, and the optimum pH value is 1.0. The results indicate that powder has an ultrafine particle size, high purity, and narrow size distribution, good fluidity, light agglomerate and is perfect in crystal.

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