Fenton's treatment of actual agriculture runoff water containing herbicides

2016 ◽  
Vol 75 (2) ◽  
pp. 451-461 ◽  
Author(s):  
Sanjeev Sangami ◽  
Basavaraju Manu
Keyword(s):  
Reaction Time ◽  
Treatment Process ◽  
Signal To Noise Ratio ◽  
Oxygen Demand ◽  
Runoff Water ◽  
Independent Variables ◽  
Dependent Variables ◽  
Removal Efficiencies ◽  
Dichlorophenoxy Acetic Acid ◽  
Maximum Removal

This research was to study the efficiency of the Fenton's treatment process for the removal of three herbicides, namely 2,4-dichlorophenoxy acetic acid (2,4-D), ametryn and dicamba from the sugarcane field runoff water. The treatment process was designed with the Taguchi approach by varying the four factors such as H2O2/COD (1–3.5), H2O2/Fe2+ (5–50), pH (2–5) and reaction time (30–240 min) as independent variables. Influence of these parameters on chemical oxygen demand (COD), ametryn, dicamba and 2,4-D removal efficiencies (dependent variables) were investigated by performing signal to noise ratio and other statistical analysis. The optimum conditions were found to be H2O2/COD: 2.125, H2O2/Fe2+: 27.5, pH: 3.5 and reaction time of 135 min for removal efficiencies of 100% for ametryn, 95.42% for dicamba, 88.2% for 2,4-D and with 75% of overall COD removal efficiencies. However, the percentage contribution of H2O2/COD ratio was observed to be significant among all four independent variables and were 44.16%, 67.57%, 51.85% and 50.66% for %COD, ametryn, dicamba and 2,4-D removal efficiencies, respectively. The maximum removal of herbicides was observed with the H2O2 dosage of 5.44 mM and Fe2+ dosage of 0.12 mM at pH 3.5.

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 Treatment of oilfield produced water with electrocoagulation: improving the process performance by using pulse current

2016 ◽  
Vol 7 (3) ◽  
pp. 378-386 ◽  
Author(s):  
Tao Zheng
Keyword(s):  
Reaction Time ◽  
Current Density ◽  
Duty Cycle ◽  
Produced Water ◽  
Oxygen Demand ◽  
Current Method ◽  
Pulse Frequency ◽  
Economic Feasibility ◽  
Electrode Distance ◽  
Removal Efficiencies

The main aim of this study is to investigate the technical and economic feasibility of the pulse electrocoagulation (PE) process on the treatment of oilfield alkali/surfactant/polymer flooding produced water. By using an Fe electrode, the performance of the PE process was analyzed in terms of operating parameters such as pulse duty cycle, current density, pulse frequency, electrode distance, and reaction time with removal efficiencies, some of which are presented in figures and others are given in tables due to the numbers of parameters. Under the optimal conditions of a pulse duty cycle of 0.3, current density of 35 mA/cm2, pulse frequency of 3.0 kHz, electrode distance of 1.0 cm, and reaction time of 40 min, the removal efficiencies of chemical oxygen demand (COD), oils and greases, turbidity, total suspended solids, and polyacrylamide reach 98.3, 99.0, 98.8, 98.1 and 94.3%, respectively, with an energy consumption of 0.19 kWh/kg CODremoved and an electrode consumption of 3.1 kg Fe/kg CODremoved. The quality of the final effluent could satisfy the requirement of the national discharge standard. Compared with the traditional direct current method, the PE process could save 76% of the energy. Moreover, the treatment performance of PE is much better than traditional chemical coagulation treatment using polymeric ferric sulfate.

scholarly journals Optimization of sequencing batch reactor for wastewater treatment using chemically enhanced primary treatment as a pre-treatment

Water SA ◽  
2018 ◽  
Vol 44 (3 July) ◽  
Author(s):  
Haroon R Mian ◽  
Sajjad Haydar ◽  
Ghulam Hussain ◽  
Gul -e-Hina
Keyword(s):  
Wastewater Treatment ◽  
Reaction Time ◽  
Sequencing Batch Reactor ◽  
Batch Reactor ◽  
Phase 1 ◽  
Oxygen Demand ◽  
Scale Model ◽  
Phase 2 ◽  
Removal Efficiencies ◽  
Raw Wastewater

The sequencing batch reactor (SBR) is a wastewater treatment option feasible for low flows. The objective of this research was to optimize SBR by varying its operational parameters, viz. (i) settling time and (ii) reaction time. The study was conducted in two phases. In Phase 1, raw wastewater was fed into the SBR after conventional settling, while in Phase 2 raw wastewater was fed into the SBR after coagulation-flocculation-sedimentation. A bench-scale model was set up and domestic wastewater was used for this study. Performance of the treatment system was evaluated through 5-day biochemical oxygen demand (BOD), chemical oxygen demand (COD) and total suspended solids (TSS). The results demonstrated that reaction time was reduced to 4 h in Phase 2 compared to 10 h in Phase 1. The BOD, COD and TSS removal efficiencies observed in Phase 1 were 80%, 80% and 73%, respectively, and for Phase 2 the removal efficiencies were 74%, 75% and 80% respectively. National Environmental Quality Standards (NEQS) were met in both cases and the treatment cost per cubic metre of wastewater for Phase 2 was 2.5 times lower compared to Phase 1.

Alternatives for treating recirculated newsprint whitewater at high temperatures

1997 ◽  
Vol 35 (2-3) ◽  
pp. 57-65 ◽  
Author(s):  
Oliver Tardif ◽  
Eric R. Hall
Keyword(s):  
High Temperatures ◽  
Biological Treatment ◽  
Membrane Bioreactor ◽  
Treatment Process ◽  
Batch Reactor ◽  
Oxygen Demand ◽  
Total Dissolved Solids ◽  
Removal Efficiencies ◽  
Treatment Alternatives ◽  
Dissolved And Colloidal Substances

Four treatment alternatives were investigated for the removal of dissolved and colloidal substances at high temperatures from a simulated closed-system mechanical newsprint whitewater: (i) sequenching batch reactor treatment (SBR), (ii) ultrafiltration (UF), (iii) biological treatment followed by UF (SBR⊕UF) and (iv) membrane bioreactor (MBR) treatment. Contaminants investigated included resin and fatty acids (RFA), dissolved organic carbon (DOC), dissolved chemical oxygen demand (DCOD) and total dissolved solids (TDS). Ultrafiltration alone yielded excellent FA removals at temperatures ranging from 20 to 60°C, but only fair removals (9 to 42%) of TDS, dissolved COD, DOC and RA. Removal efficiencies were generally enhanced when using a membrane of a smaller pore size but did not vary with temperature. The SBR was effective at removing contaminants at temperatures ranging from 20 to 40°C (up to 100% of the RA, 96% of the FA, 76% of the DCOD and 34% of the TDS were removed). However, the performance of the SBR was poor at 45 and 50°C. Batch ultrafiltration of SBR pre-treated whitewater enhanced the removal of target contaminants, compared to SBR treatment alone. The MBR was judged to be the preferable treatment process at high temperatures. It yielded consistent removal efficiencies at temperatures ranging from 40 to 55°C, removing up to 100% of RA and FA, 84% of DCOD and 37% of TDS.

Enhanced physicochemical-biological sewage treatment process in cold regions

2014 ◽  
Vol 70 (9) ◽  
pp. 1456-1464 ◽  
Author(s):  
Guoren Xu ◽  
Chao Jia ◽  
Zhao Zhang ◽  
Yunlong Jiang
Keyword(s):  
Membrane Filtration ◽  
Treatment Process ◽  
Sewage Treatment ◽  
Oxygen Demand ◽  
Ammonia Nitrogen ◽  
Pollutant Removal ◽  
Wastewater Treatment Process ◽  
Cold Regions ◽  
Removal Efficiencies ◽  
Northeast Of China

Biological treatment processes give relatively poor pollutant removal efficiencies in cold regions because microbial activity is inhibited at low temperatures. We developed an enhanced physicochemical-biological wastewater treatment process that involves micro-membrane filtration, anaerobic biofilter, and aerobic biofilter to improve the pollutant removal efficiencies that can be achieved under cold conditions. Full-scale experiments using the process were carried out in the northeast of China, at outdoor temperatures of around −30 °C. The average removal efficiencies achieved for chemical oxygen demand, total phosphorus, ammonia nitrogen, and suspended solids were 89.8, 92.9, 94.3, and 95.8%, respectively, using a polyaluminium chloride dosage of 50 mg L−1. We concluded that the process is effective to treat sewage in cold regions.

ANALISA PENGARUH IKLIM ORGANISASI DAN KOMPETENSI TERHADAP KINERJA PEGAWAI PT HUTAMA KARYA

2018 ◽  
Vol 5 (1) ◽  
Author(s):  
Erik Wardhana, MM.
Keyword(s):  
Organizational Climate ◽  
Employee Performance ◽  
Sampling Technique ◽  
Simple Random Sampling ◽  
Free Variable ◽  
Independent Variables ◽  
Dependent Variables ◽  
Correlational Approach ◽  
Survey Research Methods ◽  
The Relationship

This study entitled "Analysis of Effect of Climate Organization and Competence Againt Employee PT. Hutama Karya ". The purpose of this study was to obtain information on the relationship between the free variable that organizational climate (X1) and competence (X2) with the dependent variable is employee performance (Y), either partially or simultaneously, This study used survey research methods with the correlational approach and predictive, which aims for the relationship and influence between independent and dependent variables. The sampling technique can be done randomly (simple random sampling) of 852 employees, which is considered to resprentatif is 89 people. And to solve problems, to analyze and examine the relationship and influence between the independent variables on the dependent variable used models kausalistik through regression analysis with SPSS 14.0

PENGARUH PERSONAL BACKGROUND, POLITICAL BACKGROUND DAN PENGEATAHUAN DEWAN TENTANG ANGGARAN TERHADAP PERAN DPRD DALAM PENGAWASAN KEUANGAN DAERAH

2008 ◽  
Author(s):  
Yesi Mutia Basri ◽  
Rosliana Rosliana
Keyword(s):  
Multivariate Analysis ◽  
Significant Influence ◽  
Political Activity ◽  
Primary Data ◽  
Financial Control ◽  
Independent Variables ◽  
Dependent Variables ◽  
Political Background ◽  
Activity Dependent

This research aim to examine the influence of personal background, political background, and council budget knowledge towards the role of DPRD on region financial control. This research is motivated by the fact that individual background will effect to individual behavior on political activity. Dependent variables in this research are personal background, political background, and council budges knowledge towards the role of DPRD on region financial control Independent variables are the role of DPRD on region financial control in planning, implementing, and responsibility steps. The data in this research consist of primary data that taken from questionnaires distributed directly to respondents. The collected are from 34 Respondents that members of DPRD at Pekanbaru. Hypothesis of this research are examine by using Multivariate Analysis of Variances (MANOVA). The result of this research HI personal background political background and budget knowledge have significant influence toward the role of DPRD on region financial control in planning steps.H2 personal background, politico I background and budget knowledge have no significant influence toward the role of DPRD on region financial control in Implementing steps. H3 personal background political background and budget knowledge have no significant influence toward the role of DPRD on region financial control in Controlling steps.

Pilot Scale Testing of a New Radium-226 Removal Process

1985 ◽  
Vol 20 (2) ◽  
pp. 55-67
Author(s):  
W.B. Anderson ◽  
P.M. Huck ◽  
T.M.R. Meadley ◽  
T.P. Hynes
Keyword(s):  
Treatment Process ◽  
No Reduction ◽  
High Surface ◽  
High Surface Area ◽  
Barium Chloride ◽  
Pilot Scale ◽  
Activity Levels ◽  
New Process ◽  
Removal Efficiencies ◽  
New Treatment

Abstract This paper describes the on-going pilot scale development of a new treatment process designed to remove radium-226 from uranium milling effluents. Presently, decants from Canadian uranium mining and milling tailings areas are treated with barium chloride to remove radium-226 prior to discharge into the environment. This is usually accomplished in large natural or man-made ponds which provide an opportunity for a (Ba,Ra)SO4 precipitate to form and subsequently settle. Sand filtration is sometimes used as a polishing step. This new process differs from conventional and other experimental processes in that it involves the use of a fluidized bed to facilitate the deposition of a (Ba,Ra)SO4 precipitate on a granular medium of high surface area. As a stand-alone treatment process, the new process is consistently able to reduce incoming radium-226 activity levels by 90-99%. Effluent levels of 10 pCi/L (0.370 Bq/L) or less have been achieved, depending on the influent activity levels. Recent testing of the process as a polishing step has demonstrated radium removal efficiencies up to 60% when the process influent was already less than 5 pCi/L (0.185 Bq/L). The process has been operated at temperatures ranging from 26°C down to 0.3°C with no reduction in efficiency. In contrast to treatment times in the order of days for conventional settling pond systems and hours for mechanical stirred tank/filtration systems, the new process is able to achieve these radium removal efficiencies in times on the order of one minute.

scholarly journals Weight Feedback-Based Harmonic MDG-Ensemble Model for Prediction of Traffic Accident Severity

2021 ◽  
Vol 11 (11) ◽  
pp. 5072
Author(s):  
Byung-Kook Koo ◽  
Ji-Won Baek ◽  
Kyung-Yong Chung
Keyword(s):  
Traffic Accidents ◽  
Average Rate ◽  
Modern Society ◽  
Rate Of Change ◽  
Weighted Voting ◽  
Independent Variables ◽  
Dependent Variables ◽  
Accident Severity ◽  
Harmonic Average ◽  
Bagging Method

Traffic accidents are emerging as a serious social problem in modern society but if the severity of an accident is quickly grasped, countermeasures can be organized efficiently. To solve this problem, the method proposed in this paper derives the MDG (Mean Decrease Gini) coefficient between variables to assess the severity of traffic accidents. Single models are designed to use coefficient, independent variables to determine and predict accident severity. The generated single models are fused using a weighted-voting-based bagging method ensemble to consider various characteristics and avoid overfitting. The variables used for predicting accidents are classified as dependent or independent and the variables that affect the severity of traffic accidents are predicted using the characteristics of causal relationships. Independent variables are classified as categorical and numerical variables. For this reason, a problem arises when the variation among dependent variables is imbalanced. Therefore, a harmonic average is applied to the weights to maintain the variables’ balance and determine the average rate of change. Through this, it is possible to establish objective criteria for determining the severity of traffic accidents, thereby improving reliability.

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).

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