scholarly journals INTERACTION OF THE ABRASIVE MEDIUM WITH THE TREATED SURFACE AND THE PROCESS OF METAL REMOVAL DURING VIBRATION TREATMENT IN THE PRESENCE OF A CHEMICALLY ACTIVE SOLUTION

2021 ◽  
pp. 42-48
Author(s):  
Andrii Mitsyk ◽  
Vladimir Fedorovich ◽  
Anatoliy Grabchenko
Keyword(s):  
Metal Removal ◽  
Treatment Method ◽  
Dynamic Interaction ◽  
Physicochemical Model ◽  
Abrasive Medium ◽  
Vibration Treatment ◽  
Distinctive Features ◽  
Abrasive Grains ◽  
Active Solution ◽  
Working Medium

Interaction of working medium granules with the processed surface of the part is considered. It is noted that the processing methods are characterized by the dynamic interaction of the abrasive medium with the processed surface. It is indicated that during vibration treatment there is an impact contact of the abrasive granule with the surface of the part, which leads to the formation of characteristic traces during the formation of the surface relief. The types of impact of abrasive grains of working medium granules on the surface of the processed part are identified. It is indicated that the effect of abrasive grains depends on the geometric parameters of the tops of the grains and the working contour of the granule as a whole. The alternation of the operation of abrasive grains in the connection with the nature of the motion of the granule over the surface of the part is shown. The interaction of surfaces of bodies during vibration treatment is considered. The distinctive features of the vibration treatment method from other analogs are indicated. The conditions for the formation of the surface layer of the part during vibration processing are given. The analysis of the mechanical-physicochemical model of the micro-cutting process in the presence of a chemically active solution is carried out and a comparison of the intensity of technologies for vibration treatment of steel parts is given.

scholarly journals The Use of the Kinetic Theory of Gases to Simulate the Physical Situations on the Surface of Autonomously Moving Parts During Multi-Energy Vibration Processing

Materials ◽  
2019 ◽  
Vol 12 (19) ◽  
pp. 3054 ◽  
Author(s):  
Kundrák ◽  
Mitsyk ◽  
Fedorovich ◽  
Markopoulos
Keyword(s):  
Metal Removal ◽  
Vibration Machine ◽  
Abrasive Medium ◽  
Working Medium ◽  
Finishing Process ◽  
Part Surface ◽  
Multi Agent ◽  
Finishing Processes ◽  
Agent Group

The multi-energy vibration processing, namely the combination of different energies or forces acting on a free abrasive medium for grinding of metal parts, is becoming more used in finishing processes, in recent years. However, the complexity that is involved in the aforementioned process requires a careful look in the particularities of the process itself in general and the movement of the abrasive media, in particular. In this paper, the nature of the collective movement of abrasive granules between the independently oscillating surfaces of the reservoir and the processed parts is described. This study presents the dissipation of the kinetic energy of the granules in a pseudo-gas from the working medium granules. The motion of the medium granules near the part surface, which is caused by pseudo-waves initiated by vibrations of the working surfaces of the vibration machine reservoir, is demonstrated. Furthermore, the nature of the motion of the granules near the oscillating part surface is described. The analysis that is presented here permits the determination of metal removal quantity from the surface of the workpiece as a result of multi-agent group action of the vibrating reservoir surface and the processed part. The optimal conditions for the finishing process can be determined based on the analysis presented.

Treatment of a complex landfill leachate with peat

1978 ◽  
Vol 5 (1) ◽  
pp. 83-97 ◽  
Author(s):  
Robert D. Cameron
Keyword(s):  
Chemical Oxygen Demand ◽  
Ferric Chloride ◽  
Landfill Leachate ◽  
Metal Removal ◽  
Oxygen Demand ◽  
Treatment Method ◽  
Manganese Concentration ◽  
Chemical Pretreatment ◽  
Iron Manganese

The use of cheap, locally available peat as a treatment method for landfill leachate was investigated by passing leachate through plexiglass columns filled with an amorphous-granular peat. Preliminary adjustment of pH showed that reducing pH to 4.8 dramatically reduced adsorption. Increasing the pH to 8.4, metal removal was increased owing to filtration of precipitated metals. The best adsorption of metals occurred at the 'natural' pH of 7.1. Manganese was found to be the limiting pollutant. At the 0.05 mg/ℓ maximum acceptable manganese concentration 94% of the total metals were removed, requiring 159 kg of peat per 1000 ℓ of leachate.Resting the peat for 1 month did significantly increase removal capacity.Desorption of some contaminants occurred when water was percolated through the peat. The desorption test effluent was not toxic to fish although iron, lead and COD (chemical oxygen demand) exceeded acceptable values.Chemical pretreatment using lime and ferric chloride achieved significant iron, manganese and calcium removals. Chemical pretreatment followed by peat adsorption offered no advantage other than reducing toxicity to fish.Peat treatment alone was effective in reducing concentrations to a level that was non-toxic to fish.

Resonant excitation of rotating waves in annular zones

2020 ◽  
pp. 30-38
Author(s):  
E.D. Sviyazheninov
Keyword(s):  
Natural Frequency ◽  
Resonant Excitation ◽  
Acoustic Vibrations ◽  
Rotating Waves ◽  
Vibration Treatment ◽  
Working Medium ◽  
Annular Zone

A method and a device are developed for exciting powerful resonant acoustic rotating waves in a gaseous or liquid flowing working medium located in the annular zone between the rotor and stator, for its vibration treatment. Keywords: vibration treatment, vibrations, natural frequency, vibration form, waves, acoustic vibrations, resonance. [email protected]

Organic matter and heavy metal removals from complexed metal plating effluent by the combined electrocoagulation/Fenton process

2010 ◽  
Vol 61 (10) ◽  
pp. 2617-2624 ◽  
Author(s):  
I. Kabdaşlı ◽  
T. Arslan ◽  
I. Arslan-Alaton ◽  
T. Ölmez-Hancı ◽  
O. Tünay
Keyword(s):  
Organic Matter ◽  
Metal Removal ◽  
Treatment Method ◽  
Fenton Process ◽  
Toc Removal ◽  
Operation Conditions ◽  
Metal Plating ◽  
Wide Range ◽  
Initial Ph ◽  
H2o2 Addition

In the present study, the treatment of metal plating wastewater containing complexed metals originating from the nickel and zinc plating process by electrocoagulation (EC) using stainless steel electrodes was explored. In order to improve the organic matter removal efficiency, the effect of H2O2 addition to the electrocoagulation (the combined EC/Fenton process) application was investigated. For this purpose, a wide range of H2O2 concentrations varying between 15 and 230 mM was tested. All EC and EC/Fenton processes were performed at an initial pH of 2.6 and at an optimized current density of 22 mA/cm2. Although up to 30 mM H2O2 addition improved the EC process performance in terms of organic matter abatement, the highest COD and TOC removal efficiencies were obtained for the combined EC/Fenton process in the presence of 20 mM H2O2. Nickel and zinc were completely removed for all runs tested in the present study after pH adjustments. At the optimized operation conditions, the combined EC/Fenton process proved to be an alternative treatment method for the improvement of organic matter reduction as well as complexed metal removal from metal plating industry wastewater.

scholarly journals Assessing Options for Remediation of Contaminated Mine Site Drainage Entering the River Teign, Southwest England

Minerals ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 721 ◽  
Author(s):  
Abigail Jordan ◽  
Rachel Hill ◽  
Adrienne Turner ◽  
Tyrone Roberts ◽  
Sean Comber
Keyword(s):  
Red Mud ◽  
Metal Removal ◽  
Environmental Concern ◽  
Low Cost ◽  
Waste Product ◽  
Treatment Method ◽  
Mining Operations ◽  
Metal Concentrations ◽  
Cost Treatment ◽  
Mine Sites

The river Teign in Devon has come under scrutiny for failing to meet environmental quality standards for ecotoxic metals due to past mining operations. A disused mine known as Bridford Barytes mine, has been found to contribute a significant source of Zn, Cd and Pb to the river. Recently, studies have been focused on the remediation of such mine sites using low-cost treatment methods to help reduce metal loads to the river downstream. This paper explores the metal removal efficiency of red mud, a waste product from the aluminium industry, which has proven to be an attractive low-cost treatment method for adsorbing toxic metals. Adsorption kinetics and capacity experiments reveal metal removal efficiencies of up to 70% within the first 2 h when red mud is applied in pelletized form. Further, it highlights the potential of biochar, another effective adsorbent observed to remove >90% Zn using agricultural feedstock. Compliance of the Teign has been investigated by analysing dissolved metal concentrations and bioavailable fractions of Zn to assess if levels are of environmental concern. By applying a real-world application model, this study reveals that compressed pellets and agricultural biochar offer an effective, low-cost option to reducing metal concentrations and thus improving the quality of the river Teign.

scholarly journals Intensity increase in metal removal at vibration treatment based on use of “slot” effect in working chamber

2017 ◽  
Vol 2 (9) ◽  
pp. 33-38 ◽  
Author(s):  
Анатолий Бабичев ◽  
Anatoly Babichev ◽  
Филипп Пастухов ◽  
Philip Pastukhov ◽  
Амбогему Вобу ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Metal Removal ◽  
Intensity Increase ◽  
Vibration Treatment ◽  
Working Chamber ◽  
Section Dimension ◽  
Slot Effect

The results of the investigations on metal removal intensity increase during the vibration treatment on the basis of the “slot” effect use in a working chamber are presented. The investigation results presented show that with the decrease of a section dimension in the working chamber metal removal increases and surface roughness is getting better.

scholarly journals Biochar for wastewater treatment – a Minireview**

2021 ◽  
pp. 63-66
Author(s):  
Lena Johansson Westholm
Keyword(s):  
Wastewater Treatment ◽  
Functional Groups ◽  
Metal Removal ◽  
Thermochemical Treatment ◽  
Treatment Method ◽  
Transformation Method ◽  
Waste Products ◽  
Vast Number ◽  
Filter Materials ◽  
Wide Range

Wastewater must be treated no matter if is reused or discharged into the environment. The cost of wastewater treatment may be rather high, though other solutions are sought. One of them is the application of filter materials. The filter materials have been used for removal of various pollutants in different kinds of wastewater and a wide range of filter materials (natural products, industrial waste products or man-made products) have been investigated. Among these filter materials, biochar has attracted increasing attention during the last decade. A large number of publications are devoted to production, properties and potential applications of biochar. They reveal that biochar is capable of removing pollutants of different kinds from wastewaters. A number of experiments was focused on the removal of commonly found pollutants, e.g. nutrients, heavy metals, organic matters and pharmaceuticals. It was found that the origin of the feedstock and the thermochemical treatment method are tightly connected and will have an impact on the properties of the biochar. A large number of different feedstock material like wood or wood residues, garden wastes or human and animal wastes can be transformed into biochar by torrefaction and pyrolysis. Properties of biochar will depend on transformation method. Surface area, porosity, pH, surface charge, functional groups and mineral components contribute to a vast number of mechanisms that are responsible for the metal removal, e.g. electrostatic interaction between the surface of the biochar and the specific metal, the cation exchange capacity between metals and protons and the alkaline metals on the surface of the biochar, metal complexation with functional groups and precipitation of metals that form non-soluble compounds. Biochar was successfully applied in wetlands systems to increase the removal of some targeted pollutants.

scholarly journals Assessing Options for Remediation of Contaminated Mine Site Drainage Entering the River Teign, Southwest England

2020 ◽  
Author(s):  
Abigail Jordan ◽  
Rachel Hill ◽  
Adrienne Turner ◽  
Tyrone Roberts ◽  
sean Comber
Keyword(s):  
Red Mud ◽  
Metal Removal ◽  
Environmental Concern ◽  
Low Cost ◽  
Waste Product ◽  
Treatment Method ◽  
Mining Operations ◽  
Metal Concentrations ◽  
Cost Treatment ◽  
Mine Sites

The river Teign in Devon has come under scrutiny for failing to meet Environmental Quality Standards for ecotoxic metals due to past mining operations. A disused mine known as Bridford Barytes mine, has been found to contribute a significant source of Zn, Cd and Pb to the river. Recently, studies have been focused on the remediation of such mine sites using low-cost treatment methods to help reduce metal loads to the river downstream. Red mud is a waste product from the aluminium industry, the utilization of this resource has proven an attractive low-cost treatment method for adsorbing toxic metals. Adsorption kinetics and capacity experiments reveal metal removal efficiencies of up to 70% within the first 2 hours when red mud is applied in pelletized form. Biochar is another effective adsorbent with the potential to remove >90% Zn using agricultural feedstock. Compliance of the Teign has been investigated by analysing dissolved metal concentrations and bioavailable fractions of Zn to assess if levels are of environmental concern. By applying a Real-World Application Model, this study reveals that compressed pellets and agricultural biochar offer an effective, low-cost option to reducing metal concentrations and thus improving the quality of the river Teign.

Two-stage combined treatment of acid mine drainage and municipal wastewater

2013 ◽  
Vol 67 (5) ◽  
pp. 1000-1007 ◽  
Author(s):  
Dongyang Deng ◽  
Lian-Shin Lin
Keyword(s):  
Biological Treatment ◽  
Municipal Wastewater ◽  
Mine Drainage ◽  
Metal Removal ◽  
Combined Treatment ◽  
Oxygen Demand ◽  
Treatment Method ◽  
Phosphate Removal ◽  
Two Stage ◽  
Acid Mine

This study examined the feasibility of the combined treatment of field-collected acid mine drainages (AMD, pH = 4.2 ± 0.9, iron = 112 ± 118 mg/L, sulfate = 1,846 ± 594 mg/L) and municipal wastewater (MWW, avg. chemical oxygen demand (COD) = 234–333 mg/L) using a two-stage process. The process consisted of batch mixing of the two wastes to condition the mixture solutions, followed by anaerobic biological treatment. The mixings performed under a range of AMD/MWW ratios resulted in phosphate removal of 9 to ∼100%, the mixture pH of 6.2–7.9, and COD/sulfate concentration ratio of 0.05–5.4. The biological treatment consistently removed COD and sulfate by >80% from the mixture solutions for COD/sulfate ratios of 0.6–5.4. Alkalinity was produced in the biological treatment causing increased pH and further removal of metals from the solutions. Scanning electron microscopy of produced sludge with energy dispersion analysis suggested chemical precipitation and associated adsorption and co-precipitation as the mechanisms for metal removal (Fe: >99%, Al: ∼100%, Mn: 75 to ∼100%, Ca: 52–81%, Mg: 13–76%, and Na: 56–76%). The study showed promising results for the treatment method and denoted the potential of developing innovative technologies for combined management of the two wastes in mining regions.

scholarly journals Zeolite - A Natural Filter Material for Lead Polluted Water

2014 ◽  
Vol 64 (1) ◽  
pp. 52-56
Author(s):  
Corina Ioana Neamţu ◽  
Elena Maria Pică ◽  
Tiberiu Rusu
Keyword(s):  
Water Treatment ◽  
Filter Material ◽  
Treatment Method ◽  
Dynamic Interaction ◽  
Interaction Time ◽  
Lead Ions ◽  
Polluted Water ◽  
Zeolite A ◽  
The World ◽  
Static Conditions

Abstract Reducing the concentration of lead ions in a wastewater using zeolite has proven to be a successful water treatement method, all over the world. Putting the two media (solid and liquid) in contact in static conditions had good results regarding the concentration of the filtered solution, the pH and the electric conductivity, depending on the values of certain parameters such as the amount of the zeolite, volume of the solution or interaction time. The present study highlights the zeolite ability to retain the lead ions from a solution, in dynamic interaction conditions between the two environments, in a short interaction time. The results confirmed the effectiveness of ion exchange water treatment method in the conditions set, emphasizing once again the properties of the filter material - the zeolite

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