scholarly journals Purification of concentrated waste water of pcb production from copper ions

2021 ◽  
pp. 11-20
Author(s):  
Olena Zoria ◽  
Оleksiy Ternovtsev ◽  
Dmytro Zoria
Keyword(s):  
Ph Value ◽  
Copper Ions ◽  
Sewage Treatment ◽  
Experimental Studies ◽  
Precious Metals ◽  
Rate Of Change ◽  
Copper Extraction ◽  
Contact Exchange ◽  
Circulating Water ◽  
Static Conditions

In modern conditions, it is important to create a comprehensive technology for processing wastewater containing copper compounds, with the disposal of precious metals, the organization of circulating water supply of the enterprise and obtaining safe for disposal sludge. Methods of sewage treatment of galvanic productions are considered. The results of experimental studies of the process of copper extraction from water by cementation on iron powder particles under static conditions are presented. The technological scheme of the reactor-cementator is given. The influence of various factors on the process of copper cementation – pH, concentration and ratio of iron and copper in the reaction mixture, contact time were studied. The time at which the greatest rate of change of residual copper concentration is observed is determined. The influence of the pH value of the cementation process was also determined. As a result of the obtained data, it is concluded that the concentration of hydrogen ions in the solution affects the course of the contact exchange reaction. The higher the acidity of the solution, the higher the recovery rate of copper. Promising directions for the creation of closed water circulation systems in the process of copper wastewater treatment are outlined.

АКУСТИЧНА ПОМІТНІСТЬ БЕЗПІЛОТНИХ ЛІТАЛЬНИХ АПАРАТІВ З СИЛОВИМИ УСТАНОВКАМИ НА БАЗІ ПОРШНЕВИХ ДВИГУНІВ

2020 ◽  
pp. 62-80
Author(s):  
В. В. Руденко ◽  
И. В. Калужинов ◽  
Н. А. Андрущенко
Keyword(s):  
Control System ◽  
Internal Combustion Engine ◽  
Power Plants ◽  
Combustion Engine ◽  
Spectral Characteristics ◽  
Experimental Studies ◽  
Internal Combustion ◽  
Detection Range ◽  
Acoustic Signature ◽  
Static Conditions

The presence in operation of many prototypes of UAVs with propeller propellers, the use of such devices at relatively low altitudes and flight speeds makes the problem of noise reduction from UAVs urgent both from the point of view of acoustic imperceptibility and ecology.The aim of the work is to determine a set of methods that help to reduce the visibility of UAVs in the acoustic range. It is shown that the main source of noise from the UAV on the ground is the power plant, which includes the engine and the propeller. The parameters of the power plants influencing the processes that determine the acoustic signature of the UAV were investigated. A comprehensive analysis of the factors affecting visibility was carried out. The power plants include two-stroke and four-stroke engines, internal combustion and two-blade propellers. The use of silencers on the exhaust of the internal combustion engine was considered. The spectral characteristics of the acoustic fields of the propeller-driven power plants for the operating sample of the UAV "Eco" were obtained. The measurements were carried out in one-third octave and 1/48 octave frequency bands under static conditions. The venue is the KhAI airfield. Note that the propellers that were part of the power plants operated at Reynolds numbers (Re0,75<2*105), which can significantly affect its aerodynamic and acoustic characteristics. It is shown that when choosing a UAV control system, one should take into account the fact that two-stroke piston engines are the dominant source in the noise of propeller-driven control systems in the absence of a hood and mufflers in the intake and exhaust tracts. The use of a four-stroke internal combustion engine significantly reduces the noise of the control system. In the general case, the position of the boundaries of the zone of acoustic visibility of a UAV at the location of the observer is determined by the ratio between the intensity of acoustic radiation perceived by the observer from the UAV and the intensity of sound corresponding to the natural acoustic background and depends on the degree of manifestation of acoustic effects accompanying the propagation of sound in a turbulent atmosphere - the refraction of sound waves. Absorption and dissipation of acoustic energy. The calculation and comparison of the UAV detection range was carried out taking into account the existing natural maskers.The results of experimental studies are presented that allow assessing the degree of acoustic signature of the UAV. A set of measures aimed at reducing the intensity of the acoustic signature of the UAV in various regions of the radiation spectrum has been determined.

Experimental Studies on a Mineral Containing Titanium in Baoding Area

2013 ◽  
Vol 826 ◽  
pp. 34-37 ◽  
Author(s):  
Guo Zhen Liu ◽  
Shu Juan Dai ◽  
Li Mei Bai ◽  
Yu Xin Ma ◽  
Yong Zhang
Keyword(s):  
Magnetic Separation ◽  
High Intensity ◽  
Ph Value ◽  
Experimental Studies ◽  
Mineral Processing ◽  
Shaking Table ◽  
Gravity Concentration

The main elements can be recovered for mineral processing in a mineral containing titanium of Baoding area were Ti, Fe and V, and the elements in the main gangue minerals were Si and Al. Gravity concentration, gravity concentration-high intensity magnetic separation and gravity concentration-flotation tests were performed on the ore sample respectively. The results showed that, in the test of shaking table, when the grinding fineness was -0.074mm 93%, the productivity of concentrate can reach 32.24%; when grinding fineness was -0.074mm 93%, after gravity concentration-magnetic separation, 30.25% of concentrate productivity can be attained; when the grinding fineness was -0.074mm 85%, after gravity concentration-flotation, the productivity of concentrate was 3.31%. Maybe it's the condition of the tests wasn't controlled well, especially adjusting pH value in the flotation stage, it's hard to control, so the results were not very good.

scholarly journals Equilibrium modeling of mono and binary sorption of Cu(II) and Zn(II) onto chitosan gel beads

2016 ◽  
Vol 37 (4) ◽  
pp. 485-501 ◽  
Author(s):  
Józef Nastaj ◽  
Małgorzata Tuligłowicz ◽  
Konrad Witkiewicz
Keyword(s):  
Metal Ion ◽  
Ph Value ◽  
Experimental Studies ◽  
Process Conditions ◽  
Optimal Process ◽  
Sorption Data ◽  
Gel Beads ◽  
Two Component ◽  
Equilibrium Data ◽  
Chitosan Gel

Abstract The objective of the work are in-depth experimental studies of Cu(II) and Zn(II) ion removal on chitosan gel beads from both one- and two-component water solutions at the temperature of 303 K. The optimal process conditions such as: pH value, dose of sorbent and contact time were determined. Based on the optimal process conditions, equilibrium and kinetic studies were carried out. The maximum sorption capacities equaled: 191.25 mg/g and 142.88 mg/g for Cu(II) and Zn(II) ions respectively, when the sorbent dose was 10 g/L and the pH of a solution was 5.0 for both heavy metal ions. One-component sorption equilibrium data were successfully presented for six of the most useful three-parameter equilibrium models: Langmuir-Freundlich, Redlich-Peterson, Sips, Koble-Corrigan, Hill and Toth. Extended forms of Langmuir-Freundlich, Koble-Corrigan and Sips models were also well fitted to the two-component equilibrium data obtained for different ratios of concentrations of Cu(II) and Zn(II) ions (1:1, 1:2, 2:1). Experimental sorption data were described by two kinetic models of the pseudo-first and pseudo-second order. Furthermore, an attempt to explain the mechanisms of the divalent metal ion sorption process on chitosan gel beads was undertaken.

scholarly journals Mechanism of the process of decomposition of apatitis with phosphoric acid

2019 ◽  
Vol 81 (1) ◽  
pp. 294-297
Author(s):  
R. F. Sabirov ◽  
A. F. Makhotkin ◽  
Yu. N. Sakharov ◽  
I. A. Makhotkin ◽  
I. Yu. Sakharov
Keyword(s):  
Phosphoric Acid ◽  
Ph Value ◽  
Batch Reactor ◽  
Experimental Studies ◽  
Hydrogen Ions ◽  
Experimental Conditions ◽  
Monocalcium Phosphate ◽  
Ph Values ◽  
Whole Process ◽  
Proportional Increase

Experimental studies of the kinetics and mechanism of the process, decomposition of apatite by phosphoric acid, in the Apatite-H3PO4-H2O system without the addition of sulfuric acid have been performed. The study of the decomposition process of Kovdorsky apatite with certain particle sizes was carried out in a batch reactor with a volume of 1 dm3 with stirring of the reaction mixture, and an initial concentration of phosphoric acid of 17% by weight, at a temperature of 78–82 °C. Observation of the process was carried out by determining the concentration of phosphoric acid and the concentration of monocalcium phosphate. The acidity of the reaction mixture was determined by the pH meter readings (pH-105 MA with a glass combined-ESC-10603 electrode). It was shown that during the whole process a constant smooth increase in the pH value of the reaction mixture to pH 6 occurs. Comparison of the pH values of the reaction mixture during the actual at the time of determining the concentration of phosphoric acid and pH of phosphoric acid of the corresponding concentration in the aqueous solution shows that the pH value of the reaction mixture is significantly affected by the presence of monocalcium phosphate gel. During the process, during the first thirty minutes, the concentration of phosphoric acid decreases from 17 to 10% by weight, the corresponding quantitative formation of monocalcium phosphate gel and a proportional increase in the pH of the reaction mixture. Then, as the concentration of phosphoric acid decreases, the process slows down and does not proceed to the end under the experimental conditions. The dependence of the concentration of hydrogen ions in the reaction mixture on the time of the process of decomposition of apatite in phosphoric acid, which is presented in logarithmic coordinates, shows that the mechanism of formation of hydrogen ions during the whole process does not change. Thus, it is shown that the process of decomposition of apatite by phosphoric acid in the Apatite-H3PO4-H2O system proceeds with the formation of an intermediate product - monocalcium phosphate gel. When this occurs, a corresponding significant change in the pH values of the reaction mixture occurs. During the whole process there is a constant decrease in the concentration of phosphoric acid.

INTENSIFICATION OF DISPERSED AND FINE-GRAINED SILVER EXTRACTION IN CYANIDE HEAP LEACHING OF GOLD

2020 ◽  
Vol 26 (8) ◽  
pp. 40-48
Author(s):  
Yu. Rubtsov ◽  
◽  
А. Trubachev ◽  
E. Voronov ◽  
A. Lavrov ◽  
...  
Keyword(s):  
Noble Metals ◽  
Ph Value ◽  
Chemical Activation ◽  
Precious Metals ◽  
Federal District ◽  
Heap Leaching ◽  
Sodium Cyanide ◽  
Cycle Duration ◽  
Mining Equipment ◽  
Gold Bearing

Since the cost of gold has increased by an order of magnitude over the past 20 years, gold mining began to be carried out from ores that are not previously acceptable for heap leaching (HL) technology – these are refractory ores with thin and ultrafine inclusions of precious metals, ore with an increased silver content. In the Russian Federation, classical representations in the field of gold and silver HL prevail in design solutions. At the same time, the problem of silver leaching is considered in terms of the associated extraction of the main component. This approach is determined by a limited set of technological measures that have become an integral part of the classic technological regulation: ore crushing to the class –200–40 mm, sodium cyanide consumption at the level of 0,5 kg/t; pH value – 10,5; cycle duration 65 days or more; gold concentration in production solutions – fractions, mg/l; using activated carbon for sorption of noble metals. Processing ores with silver contents of 30 g/t and a more classical approach to gold HL does not allow to increase the degree of extraction. There is a need to modernize the circuit or change the parameters of the technological regulations. The object of the study was a sample of poor quartz ore provided by the customer developing one of the gold and silver deposits of the Far Eastern Federal District, the object was to increase the degree of leaching of silver from poor gold-bearing ores without changing the technological scheme and without attracting additional mining equipment. Critical analysis of literary data was carried out and the main directions of gold production from poor gold-bearing ores were identified. Chemical and mineralogical compositions of silver-containing minerals and ore rocks were investigated. Forms of association of silver with ore minerals and rocks have been established. The option of physical and chemical activation of increase of reactivity of cyanide solutions during heap leaching of silver from poor gold-bearing ores is chosen. In laboratory conditions, it was found that an increase in the concentration of sodium cyanide by 6 times or more contributes to a satisfactory extraction of gold both in agitation and percolation leaching of silver. However, in the latter case, the positive result was obtained only with the use of solutions with increased reactivity

Adsorption of Copper Ions from Wastewater by Carboxymethylcellulose Sulfate

2011 ◽  
Vol 393-395 ◽  
pp. 1098-1101 ◽  
Author(s):  
Yan Yu ◽  
Feng Yuan Huang
Keyword(s):  
Contact Time ◽  
Copper Concentration ◽  
Adsorption Process ◽  
Ph Value ◽  
Copper Ions ◽  
Adsorption Capacities ◽  
Monolayer Adsorption ◽  
Optimum Ph ◽  
Equilibrium Data ◽  
Langmuir Isotherm Model

In the present paper, the ability of carboxymethylcellulose sulfate (CMC-S) for Cu(II) removal was studied. The influence of factors, such as the pH value, the initial copper concentrations, and the contact time, were investigated in detail. Atomic absorption spectrophotometer was applied to determined the concentration of Cu(II). The results showed that the adsorption process was strongly dependent on the pH value and the initial copper concentration. The optimum pH value was in the range of 6-7. The theoretical adsorption capacities for Cu(II) was 127.7 mg/g. The equilibrium data was well fitted to the Langmuir isotherm model at 25°C, which can be explained as a monolayer adsorption.

Numerical Study of a Multipurpose Power Generator Using the Finite Element Method

2014 ◽  
Author(s):  
J. Agbormbai ◽  
N. Goudarzi ◽  
W. D. Zhu
Keyword(s):  
Finite Element ◽  
Electromotive Force ◽  
Hybrid Electric Vehicle ◽  
Numerical Study ◽  
Fuel Efficiency ◽  
Experimental Studies ◽  
Fixed Number ◽  
Tetrahedral Mesh ◽  
Static Conditions ◽  
Operational Range

Analytical and experimental analyses of a variable electromotive-force generator (VEG) show the advantages of this modified generator in hybrid electric vehicle and wind turbine applications with enhancing the fuel efficiency and expanding the operational range, respectively. In this study, electromagnetic analysis of a modified two-pole DC generator with an adjustable overlap between the rotor and the stator is studied using 3-D finite element simulation in ANSYS. The generator stator is modeled with two opposite pole pieces whose arcs span between 15° to 90° in the counterclockwise direction and −15° to −90° in the clockwise direction. A semicircular cylinder whose arc spans between −90° and 90° is used to model the generator rotor. A tetrahedral mesh is used to provide a solution for changes in the electromotive force at different frequencies and overlap ratios. For a constant electromagnetic flux density and fixed number of coils, the changes in the electromotive force at different overlap ratios between the rotor and the stator are obtained in static conditions. There is a very good correlation between the results from simulation and those from analytical and experimental studies.

Removal of Copper Ion in Industrial Wastewater by Magnetic Flocculation Experimental Research

2013 ◽  
Vol 295-298 ◽  
pp. 1231-1234 ◽  
Author(s):  
Yong Gui Yang ◽  
Yun Long Yang ◽  
Xiao Hong Kang
Keyword(s):  
Industrial Wastewater ◽  
Ph Value ◽  
Copper Ions ◽  
Removal Rate ◽  
Copper Ion ◽  
Good Effect ◽  
Magnetic Powder ◽  
Wastewater Discharge ◽  
Sedimentation Time

An experiment on the removal of heavy metal copper ions from industrial wastewater by magnetic flocculation was studied and the influences of PFS dosage static sedimentation time，temperature，pH value and magnetic powder dosage on treatment effect were discussed at the same time .The result of the test showed that when the dosage of PFS and magnetic powder were 100 and 400 mg/l respectively the pH value was 8.0，the static sedimentation time was 20min, the said process had a good effect on copper containing wastewater treatment. The removal rate of copper ions was over 97％，and the mass concentration of copper ions in the effluent water was below 0.5mg/l. Therefore after be treated by magnetic flocculation the quality of copper-containing wastewater could meet the requirement of GB 8978-1996 Integrated Wastewater Discharge Standard .

The Change of Environmental in Sewage Sludge Compost

2015 ◽  
Vol 733 ◽  
pp. 334-337
Author(s):  
Ang Li ◽  
Li Na Sun
Keyword(s):  
Moisture Content ◽  
Ph Value ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Sludge Disposal ◽  
Early Rise ◽  
Value Changes ◽  
Sludge Composting ◽  
Maturity Parameters

By aerobic composting bin type of sewage treatment plant sludge composting, through periodic sampling, research composting process temperature, moisture content, PH value changes and study the changes in compost maturity parameters of the DH. The results show that the compost temperature increased rapidly in the early rise in the first two days when fast to 50 degrees Celsius, in the tenth day decreased to room temperature; moisture content than the original sludge reduced by 40 percent to compost indicators; PH by reaction initial 6.2, and gradually becomes neutral and alkaline 7.8 biased. Experiments show that after aerobic sludge composting in temperature, moisture content, PH value terms have been reached sludge disposal requirements.

scholarly journals Study on Fluid-Rock Interaction and Reuse of Flowback Fluid for Gel Fracturing in Desert Area

Geofluids ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Tianbo Liang ◽  
Linjie Shao ◽  
Erdong Yao ◽  
Jie Zuo ◽  
Xiongfei Liu ◽  
...  
Keyword(s):  
Ph Value ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Reservoir Rock ◽  
Chemical Compositions ◽  
Desert Area ◽  
Rock Interaction ◽  
Flowback Water ◽  
Reservoir Conditions

Hydraulic fracturing requires a large volume of fresh water, which is difficult and expensive to obtain in the desert area such as Tarim Basin. Currently, flowback fluid is typically transported to the sewage treatment plant and then discharged after reaching environmental requirements; however, this is not only costly, but also a waste of water resource. Therefore, it is imperative to understand the potential interactions between fracturing fluid and reservoir rock, and then find solutions to reuse the flowback water for subsequent fracturing. In this study, once flowback fluid was directly collected from the field, its chemical compositions were analyzed; then, filtering, decoloring, and chelating methods were chosen to effectively remove or shield the unfavorable reintroduced components. Moreover, pH value was further tuned during different stages of the recycling process to ensure good gelation and cross-linking properties of guar. Cross-linked guar synthesized with the flowback fluid was evaluated in the lab through shear resistance tests and coreflood tests under the reservoir conditions; results indicated the recycled gel behaved similarly as the original gel, or even better. From this work, a cheap and effective treatment process was proposed to reuse the flowback fluid in the desert area.

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