scholarly journals Hydrogenotrophic denitrification for treating nitrate contaminated without/with reactive black 5 dye

2020 ◽  
Vol 10 (3) ◽  
pp. 200-213
Author(s):  
Tippawan Singhopon ◽  
Kenta Shinoda ◽  
Suphatchai Rujakom ◽  
Futaba Kazama
Keyword(s):  
Treatment Time ◽  
Removal Rate ◽  
Textile Wastewater ◽  
The Other ◽  
Reactive Black 5 ◽  
Combined Process ◽  
Anaerobic Reactors ◽  
Aerobic Reactor ◽  
Set Up ◽  
Gas Supply

Abstract NO3-N and dye colors discharged from textile wastewater pose environmental problems in Thailand. This study aimed to observe the nitrogen removal rate (NRR) with and without RB-5 color contamination via hydrogenotrophic denitrification (HD) processing, which uses H2 gas as electron donor to reduce NO3-N and NO2-N; comparing with bioreactors treatment to evaluate systems that can simultaneously remove NO3-N and dye color. Five reactors under different operation and gas supply conditions were set-up under HRT of 24 h, including an aerobic reactor using air, two anaerobic reactors using argon and H2, and a combined process using intermittent air/argon and air/H2. NRR without dye varied between 45 and 90% for H2 and air/H2 by HD processing, while it was completely removed when adding color. H2 and air/H2 reactors experienced partial decolorization of approximately 20–30%, whereas the other three reactors remained unchanged. Effluent of NO3-N were close to wastewater standards, but the color was still easy to detect, which indicated that the treatment time needs to be sufficient. In conclusion, HD and intermittent air/H2 processing can completely remove NO3-N and NO2-N when contaminated with RB-5 color. Furthermore, RB-5 did not affect the NRR, whereas some particles of dye color can also reduce in these processes.

scholarly journals Factors Affecting the Simultaneous Removal of Nitrate and Reactive Black 5 Dye via Hydrogen-Based Denitrification

Water ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 922
Author(s):  
Tippawan Singhopon ◽  
Kenta Shinoda ◽  
Suphatchai Rujakom ◽  
Futaba Kazama
Keyword(s):  
Flow Rate ◽  
Nitrogen Removal ◽  
Removal Rate ◽  
Textile Wastewater ◽  
Pollutant Removal ◽  
Bacterial Degradation ◽  
Reactive Black 5 ◽  
Simultaneous Removal ◽  
Removal Rates ◽  
Similar Treatment

Textile wastewater (TW) contains toxic pollutants that pose both environmental and human health risks. Reportedly, some of these pollutants, including NO3-, NO2- and reactive black 5 (RB-5) dye, can be removed via hydrogen-based denitrification (HD); however, it is still unclear how different factors affect their simultaneous removal. This study aimed to investigate the effect of H2 flow rate, the sparging cycle of air and H2, and initial dye concentration on the TW treatment process. Thus, two reactors, an anaerobic HD reactor and a combined aerobic/anaerobic HD reactor, were used to investigate the treatment performance. The results obtained that increasing the H2 flow rate in the anaerobic HD reactor increased nitrogen removal and decolorization removal rates. Further, increasing the time for anaerobic treatment significantly enhanced the pollutant removal rate in the combined reactor. Furthermore, an increase in initial dye concentration resulted in lower nitrogen removal rates. Additionally, some of the dye was decolorized during the HD process via bacterial degradation, and increasing the initial dye concentration resulted in a decrease in the decolorization rate. Bacterial communities, including Xanthomonadaceae, Rhodocyclaceae, and Thauera spp., are presented as the microbial species that play a key role in the mechanisms related to nitrogen removal and RB-5 decolorization under both HD conditions. However, both reactors showed similar treatment efficiencies; hence, based on these results, the use of a combined aerobic/anaerobic HD system should be used to reduce organic/inorganic pollutant contents in real textile wastewater before discharging is recommended.

Experimental Study on the Plasticizer Wastewater Treatment by UASB-A/O Process

2014 ◽  
Vol 955-959 ◽  
pp. 2574-2580
Author(s):  
Zhi Yong Yu ◽  
Jia Ze Bao ◽  
Jian Guo Jiang ◽  
Wu Sheng Ma ◽  
Jin Yao Yang
Keyword(s):  
Experimental Study ◽  
Wastewater Treatment ◽  
Optimal Condition ◽  
Removal Rate ◽  
The Other ◽  
High Concentration ◽  
Combined Process ◽  
Other Hand ◽  
Aerobic Zone

Plasticizer wastewater of high concentration was experimentally studied by the process of pretreatment of acidification demulsion and Fe-C micro-electrolysis and combined process of UASB and A/O aiming at the CODCr removal in this work. The result showed that the CODCr removal rate of pretreatment process arrived at 56.2% after Fe-C micro-electrolysis reaction of 160 min on the optimal condition of pH 3.5 of acidification demulsion and 1:1.2 of the Fe/C ratio, and meanwhile improved the biodegradability of wastewater. On the other hand, UASB-A/O process could afford 80~85% of the CODCr removal rate under the optimized condition of temperature 30~35 °C, HRT 48h, pH 6.5 for UASB and HRT of aerobic zone 10~12 h, DO of about 3mg/L for A/O basin. The whole system could run at the total CODCr removal rate of 94.53~96.36%, and the system effluent CODCr was 500 mg/L or less.

scholarly journals Optimisation of Reactive Black 5 dye removal by electrocoagulation process using response surface methodology

2016 ◽  
Vol 75 (4) ◽  
pp. 952-962 ◽  
Author(s):  
W. T. Mook ◽  
M. K. Aroua ◽  
M. Szlachta ◽  
C. S. Lee
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Treatment Time ◽  
Textile Wastewater ◽  
Coefficient Of Determination ◽  
Percentage Error ◽  
Reactive Black 5 ◽  
Solution Ph ◽  
Initial Ph ◽  
Electrocoagulation Process

In this work, a regression model obtained from response surface methodology (RSM) was proposed for the electrocoagulation (EC) treatment of textile wastewater. The Reactive Black 5 dye (RB5) was used as a model dye to evaluate the performance of the model design. The effect of initial solution pH, applied current and treatment time on RB5 removal was investigated. The total number of experiments designed by RSM amounted to 27 runs, including three repeated experimental runs at the central point. The accuracy of the model was evaluated by the F-test, coefficient of determination (R2), adjusted R2 and standard deviation. The optimum conditions for RB5 removal were as follows: initial pH of 6.63, current of 0.075 A, electrolyte dose of 0.11 g/L and EC time of 50.3 min. The predicted RB5 removal was 83.3% and the percentage error between experimental and predicted results was only 3–5%. The obtained data confirm that the proposed model can be used for accurate prediction of RB5 removal. The value of the zeta potential increased with treatment time, and the X-ray diffraction pattern shows that iron complexes were found in the sludge.

scholarly journals Industrial Textile Wastewater Ozone Treatment: Catalyst Selection

Catalysts ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 611
Author(s):  
Lucyna Bilińska ◽  
Kazimierz Blus ◽  
Magdalena Bilińska ◽  
Marta Gmurek
Keyword(s):  
Catalytic Effect ◽  
Treatment Time ◽  
Oxygen Demand ◽  
Textile Wastewater ◽  
Catalytic Ozonation ◽  
Ozone Treatment ◽  
Reactive Black 5 ◽  
Short Treatment ◽  
Extensive Discussion ◽  
Textile Wastewater Treatment

One of the recent trends in textile wastewater treatment has become catalytic ozonation. The necessity of effective color removal in a short treatment time is a standard during industrial implementation. At the same time, efficient chemical oxygen demand (COD), total organic carbon (TOC), and toxic by-product removal are highly expected. This study presents the results of a catalytic ozonation treatment. Three types of catalysts: a metal oxide (TiO2 as P25 by Degussa), activated carbon (nano-powder by Sigma, AC), and metal particles (platinum, 1% wt. supported on AC matrix by Sigma, Pt–AC) have been applied. The investigations were conducted for real industrial wastewater originated in textile dyeing with Reactive Black 5 dye (RB5). The experiments ran for the raw wastewater (without pretreatment), exposed blocking of the catalytic action by all used catalysts. The catalytic effect could be observed when catalytic ozonation was used as a polishing step after electrocoagulation (EC). Although the catalytic effect could be observe for all catalysts then, especially in the removal of colorless by-products, the AC was exposed as the most effective. This contributed to 35% and 40% of TOC and COD removal. While only 18% and 23% of TOC and COD were removed in the same process without AC. The decrease in toxicity was 30%. The results of the study revealed the complexity of the issue and resulted in an extensive discussion devoted to the basis of the catalytic activity of each catalyst.

Doctrine and Dialectic in Plato’s Dialogues

2018 ◽  
Author(s):  
Rachana Kamtekar
Keyword(s):  
Methodological Approach ◽  
The Other ◽  
Set Up

Chapter 1 lays out the methodological approach employed throughout the book, which is to pay attention to the dialectical dependence of what the main speaker in the dialogue says on the intellectual problem(s) set up in the dialogue both by himself and the other speakers. To illustrate, Chapter 1 describes Socrates’ use of the method of hypotheses from the Meno and Phaedo to answer questions that go beyond his claims to knowledge in the Republic.

scholarly journals Preparation of alcohol-based handrub in COVID-19 Alsatian cluster

2020 ◽  
Vol 5 (1) ◽  
Author(s):  
Elodie Di-Falco ◽  
Johan Bourbon ◽  
Isalyne Sbaffe ◽  
Jean-Daniel Kaiser
Keyword(s):  
Critical Period ◽  
Hospital Management ◽  
Management Team ◽  
The Other ◽  
Packaging Materials ◽  
Local Production ◽  
Technical Grade ◽  
Hand Sanitizer ◽  
Set Up ◽  
Real Challenge

AbstractAlsace, in particular Haut-Rhin, is one of the main clusters of COVID-19 in France. There has been a shortage of essential supplies in the area, especially alcohol-based hand sanitizer. In this context, and in accordance with the decree dated March 6, 2020, our hospital management team asked us to start local production of alcohol-based handrub. This was a real challenge: In one week, we had to implement the production of handrub to meet the needs of a 1,400-bed hospital. The production had to comply with the French preparation guidelines and take place on specific premises, with qualified and calibrated equipment, by qualified staff, under the supervision of a pharmacist. The other big challenge we faced was the supply of pharmaceutical raw and packaging materials. During this particular critical period, all suppliers were out of stock. Here, we describe the organizational set-up and the decisions made, e. g., to use technical-grade ethanol before the publication of the decrees dated March 13 and March 23, 2020.

scholarly journals Astronomy to understand a human environment

1998 ◽  
Vol 162 ◽  
pp. 211-213
Author(s):  
S. Isobe
Keyword(s):  
School System ◽  
Environmental Science ◽  
The Other ◽  
Human Environment ◽  
Science Courses ◽  
The Public ◽  
Global Environmental Problems ◽  
Global Environmental ◽  
Set Up ◽  
School Period

Astronomy is an important science in understanding a human environment. However, it is thought by most politicians, economists, and members of the public that astronomy is a pure science having no contribution to daily human activities except a few matters relating to time. The Japanese government is studying a reorganisation of our school system to have 5 school days per week, instead of 6 days per week, and this July its committee made a recommendation to reduce school hours for science and set up new courses for practical computers and environmental science. I currently made a proposal. It is very difficult for most of the school pupils, who will have non-scientific jobs, to understand science courses currently taught in school, because each science is taught independently from the other sciences. Therefore, their knowledge of sciences obtained during their school period does not greatly help their understanding of global environmental problems.

Hypertriglyceridemia: Apheretic Treatment

2005 ◽  
Vol 28 (10) ◽  
pp. 1018-1024 ◽  
Author(s):  
G. Giannini ◽  
M. Valbonesi ◽  
F. Morelli ◽  
P. Carlier ◽  
M.C. De Luigi ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Acute Pancreatitis ◽  
Bone Marrow Transplantation ◽  
High Risk ◽  
Cyclosporin A ◽  
Marrow Transplantation ◽  
Removal Rate ◽  
The Other ◽  
Two Factors ◽  
High Triglyceride

Patients with extremely high triglyceride levels and associated lipemia are at high risk for acute pancreatitis. Two factors can increase triglyceride-rich lipoproteins; one is overproduction and other is a defect in clearance. Either mechanism can cause hypertriglyceridemia and both may exist simultaneously. Causes can be either primary or secondary. Plasmapheresis is efficacious for severe hypertryceridemia in patients who have not responded to previous therapies. We have treated 15 cases of hypertrygliceridemia complicating the course of patients receiving Cyclosporin A after bone marrow transplantation. Five patients were treated with plasmapheresis, the other ten with cascade filtration. The removal rate for triglycerides was 58.0% for patients treated by cascade filtration and 63.5% for patients treated by plasmapheresis. The removal rates for triglycerides were low possibly as a consequence of early saturation of the filter.

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