scholarly journals Study on Optimization of Tungsten Ore Flotation Wastewater Treatment by Response Surface Method (RSM)

Minerals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 184
Author(s):  
Liping Zhang ◽  
Xiaofei Jiao ◽  
Shengnian Wu ◽  
Xuejing Song ◽  
Ruihan Yao

A large amount of collectors, inhibitors and modifiers such as oleic acid, water glass and sodium carbonate are added to the flotation processing of tungsten ore, resulting in the difficulty of the suspended solids (SS) with the residual water glass settling down in the flotation wastewater. The removal efficiency of the suspended solids is low with commonly used reagents like polyaluminium chloride (PAC) and polyacrylamide (PAM). This paper innovatively applied calcium chloride (CaCl2) to treat flotation wastewater and optimized the dosage of CaCl2, PAM and the pH value. The experimental results showed that when the dosage of 595 mg/L CaCl2 was combined with 21 mg/L PAM at pH 12, the turbidity removal ratio could reach 99.98%, and the residual turbidity of the supernatant was 0.23 NTU. The effluent could fully meet the requirements for reuse in industrial, urban miscellaneous and scenic environment water consumption (turbidity < 5 NTU). The quadratic equation model fitted with Design-Expert 8.0.6 software was constructed as Y = 91.52 + 8.68A + 1.11B − 1.02C − 1.7AB + 0.86AC + 0.06BC − 1.56A2 + 2.09B2 − 1.89C2, which had a good accuracy of the predicted responses versus the experimental data.

2012 ◽  
Vol 260-261 ◽  
pp. 1074-1078 ◽  
Author(s):  
Yong Li Zhang ◽  
Zhi Zhen Huang ◽  
Man Man Zhou

Investigated the influence of absorbency, turbidity and suspended substance in printing wastewater treatment by regulating the pH value of water treatment. Firstly, was acidified the wastewater samples to 5, 4, 3, 2, then alkalize them to 8、9、10、11、12. Calculated decolorization removal, turbidity removal and the suspended substance removal. The results show that, the decolorization removal and the turbidity removal were low after acidification. While after alkalized treatment the decolorization removal and the turbidity removal were all rise. The decolorization removal and turbidity removal increased following with the increase of pH of samples that first acidified and then alkalized. And it was the most obvious when the pH was 12. When the wastewater samples first acidized the pH to 4 and then alkalized the pH to 12, the dispose effects was the best. In these conditions, the decolorization removal and turbidity removal could reach 57.7 % and 72.8 %. After acidification, the suspended solids removal came down followed with the rise of pH value. As the water samples in same acidification value and then alkalized, with the increase of pH, the suspended solids removal first rose and then came down. It could get the best dispose effects at the pH 11, the suspended solids removal could reach 41.4 %.


Coatings ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 656
Author(s):  
Junjie Shu ◽  
Yang Wang ◽  
Bei Guo ◽  
Weihua Qin ◽  
Lanxuan Liu ◽  
...  

Silver-based high-conductivity coatings are used in many advanced manufacturing equipment and components, and existing coatings require high-temperature curing. This paper studies the effects of different curing agents on the electrical properties of low-temperature curing (<100 °C) conductive coatings, and analyzes the effects of different curing temperatures and curing time on the surface resistance, square resistance and resistivity of conductive coatings. The response surface method in Design Expert was used to construct the model, and the curing thermodynamics of different curing agents were analyzed by DSC. It was found that curing agents with lower Tm and activation energy, higher pre-exponential factor and more flexible segments are beneficial to the preparation of highly conductive coatings.


Water ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2024
Author(s):  
Abderrezzaq Benalia ◽  
Kerroum Derbal ◽  
Amel Khalfaoui ◽  
Raouf Bouchareb ◽  
Antonio Panico ◽  
...  

The coagulation–flocculation–sedimentation process is widely used for removal of suspended solids and water turbidity reduction. The most common coagulants used to conduct this process are aluminum sulfate and ferric sulfate. In this paper, the use of Aloe vera as a natural-based coagulant for drinking water treatment was tested. The bio-coagulant was used in two different forms: powder as well as liquid; the latter was extracted with distilled water used as a solvent. The obtained results showed that the use of the natural coagulant (Aloe vera) in both powder (AV-Powder) and liquid (AV-H2O) forms reduced the water turbidity at natural pH by 28.23% and 87.84%, respectively. Moreover, it was found that the use of the two previous forms of bio-coagulant for drinking water treatment had no significant influence on the following three parameters: pH, alkalinity, and hardness. The study of the effect of pH on the process performance using Aloe vera as a bio-coagulant demonstrated that the maximum turbidity removal efficiency accounted for 53.53% and 88.23% using AV-Powder and AV-H2O, respectively, at optimal pH 6.


2019 ◽  
Vol 9 (02) ◽  
pp. 69-73
Author(s):  
Yuliyanto Yuliyanto

This study looked at the effect of severed EDM process parameters on the optimum value of titanium alloy hardness. this study uses Design Expert 9.0 software to help develop an experimental plan of response surface method models and CCD. The machine used is Hitachi Electrical Discharge Machining (EDM) brand with Series H-DS02-S. Material used titanium 6Al-4V. Electrode used copper (Cu). The process parameters used are Current (A), On time (μs) and Off time (μs). Coolant fluid using Hydroseal 63H. The results of data processing there are 20 experiments. This research shows optimum machining condition for hardness (HV) is 322. Analysis of variance (Anova) shows the value of F arithmetic is 3,94, MSE is 0,022 and p (0,0794). The increase of current and on-time values ​​gives a great influence on surface roughness. The increase of Off time value does not give significant effect to the roughness. The next research will be done with 5 (five) process parameters, Current, On time, Off time, Machining Voltage and Servo feed.


2013 ◽  
Vol 295-298 ◽  
pp. 1258-1262
Author(s):  
Jun Sheng Hu ◽  
Lei Guan ◽  
Jia Li Dong ◽  
Ying Wang ◽  
Ying Yong Duan

Using electrochemical oxidation method treats the acid red 3R simulation wastewater, investigates the influence of current density, electrolyte concentration, pH-value and aeration and their interaction on the removal rate of chroma. Through the design of Box-Benhnken Design(BBD) and the response surface analysis, the influence sequence of all variables is current density > aeration > electrolyte concentration > pH-value, the influence sequence of all interaction is electrolyte concentration-aeration > current density-aeration ,electrolyte concentration-pH value > current density-pH value > pH value-aeration > current density-electrolyte concentration. Ultimately, the optimal value is 98.4915% under the condition of current density of 6.51mA/cm2,electrolyte concentration of 0.04mol/L,pH-value of 4.17 and aeration of 0.24m3/h.


2016 ◽  
Vol 51 (4) ◽  
pp. 377-387 ◽  
Author(s):  
Kshitij Ranjan ◽  
Shubhrasekhar Chakraborty ◽  
Mohini Verma ◽  
Jawed Iqbal ◽  
R. Naresh Kumar

Sequencing batch reactor (SBR) was assessed for direct co-treatment of old landfill leachate and municipal wastewater for chemical oxygen demand (COD), nutrients and turbidity removal. Nitrogen removal was achieved by sequential nitrification and denitrification under post-anoxic conditions. Initially, SBR operating conditions were optimized by varying hydraulic retention time (HRT) at 20% (v/v) landfill leachate concentration, and results showed that 6 d HRT was suitable for co-treatment. SBR performance was assessed in terms of COD, ammonia, nitrate, phosphate, and turbidity removal efficiency. pH, mixed liquor suspended solids, mixed liquor volatile suspended solids (MLVSS), and sludge volume index were monitored to evaluate stability of SBR. MLVSS indicated that biomass was able to grow even at higher concentrations of old landfill leachate. Ammonia and nitrate removal efficiency was more than 93% and 83%, respectively, whereas COD reduction was in the range of 60–70%. Phosphate and turbidity removal efficiency was 80% and 83%, respectively. Microbial growth kinetic parameters indicated that there was no inhibition of biomass growth up to 20% landfill leachate. The results highlighted that SBR can be used as an initial step for direct co-treatment of landfill leachate and municipal wastewater.


2016 ◽  
Vol 75 (3) ◽  
pp. 581-586 ◽  
Author(s):  
Zheng Zhou ◽  
Aiqin Shan ◽  
Yuxia Zhao

In this study, a novel magnetic polyacrylamide (PAM) coagulant based on the core of magnetite (Fe3O4), with oleic acid serving as modifier and acrylamide as monomer, was synthesized to remove suspended solids in kaolin-suspended water. The composites were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, thermo gravimetric analysis and scanning electron microscopy. The results demonstrated that 82.8% of turbidity removal rate was obtained in 5 min of static settling in simulated kaolin-suspended water. This proved to be superior to that of PAM and poly aluminum chloride. Also confirmed in this study was the fact that zeta potential was significantly correlated with turbidity removal.


2019 ◽  
Vol 6 (2) ◽  
Author(s):  
Natalia Putri Erva Simbolon ◽  
Bhakti Etza Setiani ◽  
Anang Mohammad Legowo

Dekke mas na niurais a typical local food of North Sumatra made from carp which does not undergo cooking processes such as frying, steaming, burning, or boiling but is only paraded. This study aimed to estimate the shelf life oDekke mas na niura is a typical local food of North Sumatra made from carp which does not undergo cooking processes such as frying, steaming, burning, or boiling but is only paraded. This study aimed to estimate the shelf life of pasta seasonings using the Arrhenius equation model Accelerated Shelf Life Test (ASLT). This research was conducted at the Laboratory of Food Chemistry and Nutrition, Faculty of Animal Science and Agriculture, Diponegoro University, Semarang. The materials used in making seasonings dekke mas na niura are andaliman, pecan, turmeric, kecombrang / rias, onion, garlic, salt, red chili, lime, kaffir lime, galangal, and peanuts. The method used for making pasta spices is by mixing spices and grinding ingredients until smooth. Seasonings are stored at 25°C, 30°C, 35°C and 40°C for 24 hours of storage. The Analysis is carried out every 6 hours. The parameters tested were Aw value, pH value, and total bacteria (TPC). The results of the test data are then made linear regression with the making of orders 0 and order 1, then from the data, the shelf life calculation is done with the Arrhenius equation. The results showed that the highest Aw, pH, and total bacterial values were at 40°C which were stored for 24 hours. The critical point used in estimating shelf life is total bacterial order 1. Estimation of shelf life based on total bacteria is 5.6 days (25°C); 7.1 days (30°C); 5.6 days (35°C); and 5.2 days (40°C). Storage of pasta ingredients dekke mas na niura optimum at 30°C. Overall, the higher the storage temperature and storage time, the shorter the shelf life.f pasta seasonings using the Arrhenius equation model Accelerated Shelf Life Test (ASLT). This research was conducted at the Laboratory of Food Chemistry and Nutrition, Faculty of Animal Science and Agriculture, Diponegoro University, Semarang. The materials used in making seasonings dekke mas na niura are andaliman, pecan, turmeric, kecombrang / rias, onion, garlic, salt, red chili, lime, kaffir lime, galangal, and peanuts. The method used for making pasta spices is by mixing spices and grinding ingredients until smooth. Seasonings are stored at 25°C, 30°C, 35°C and 40°C for 24 hours of storage. The Analysis is carried out every 6 hours. The parameters tested were Aw value, pH value, and total bacteria (TPC). The results of the test data are then made linear regression with the making of orders 0 and order 1, then from the data, the shelf life calculation is done with the Arrhenius equation. The results showed that the highest Aw, pH, and total bacterial values were at 40°C which were stored for 24 hours. The critical point used in estimating shelf life is total bacterial order 1. Estimation of shelf life based on total bacteria is 5.6 days (25°C); 7.1 days (30°C); 5.6 days (35°C); and 5.2 days (40°C). Storage of pasta ingredients dekke mas na niura optimum at 30°C. Overall, the higher the storage temperature and storage time, the shorter the shelf life.


Author(s):  
Muzher Al doury ◽  
Hadeel Al samerrai

The use of conventional flocculants such as Aluminum sulphate (Alum) alone to treat the wastewater may be insufficient to get the required turbidity, suspended solids removal as well as it requires relatively a long residence time. Magnetic flocculation is one of the used techniques for increase the efficiency of the turbidity removal. In the present study, three sets of experiments are carried out in order to investigate the possibility of increasing the suspended solid removal efficiency from Al Doura oil refinery wastewater using iron oxide (Fe3O4), Nickel (Ni), and Cobalt (Co) ferromagnetic powders with alum. The following operating conditions namely, pH, alum dose, ferromagnetic powder dose, and initial turbidity are studied. The results revealed that an improvement in turbidity removal efficiency is satisfied, as well as, a reasonable reduction in the sedimentation period is achieved. The highest turbidity removal is 99.88% that obtained for 122NTU sample for alum dose 120 mg/L+ Nickel dose of 80mg/L and pH of 6.5.


2004 ◽  
Vol 155 (12) ◽  
pp. 540-543
Author(s):  
Peter Niemz ◽  
Hernan Poblete ◽  
Frank Schanack ◽  
Fritz Bächle

Pinus radiata wood was treated under hydrothermal conditions(steam) in an autoclave. The effect of temperature and time were studied. Bending strength, equilibrium moisture content, swelling and pH value of residual water were determined. Following effects were determined: a) a reduction of pH value, b) a considerable reduction of wooden mass, c) a reduction of equilibrium moisture up to 75% air humidity was registered. With higher air humidity no differences between treatments were detected, and d) with higher temperatures and longer treatment time, a reduction of bending strength was ascertained.


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