scholarly journals Energy-saving integrated ferritisation treatment of nickel-containing wastewater

Author(s):  
Gennady Kochetov ◽  
DM Samchenko ◽  
BM Yemchura

Modern requirements to electroplating waste treatment necessitate development of technologies that would allow on-site recycle and reuse of both treated water and residuals of water processing. The most prospective option for introduction of recourse-saving wastewater purification is associated with application the method of ferritisation. In this connection, the paper presents an advanced ferritisation process for reduction of initial concentrations of heavy metals (HM) in exhausted nickel electroplating electrolytes from 100 mg/L to 0.3 mg/L. Effects of main technological parameters of such wastewater treatment at thermal and electromagnetic pulse methods of activation of the ferritisation process were determined experimentally. Kinetics of removal of nickel and iron ions from aqueous solutions was investigated. Phase compositions and properties of sediments from wastewater treated were studied. The sediments are predominantly characterised by crystalline nanostructures, ferromagnetic properties and chemical stability, supporting opportunities for their environmentally sound utilisation. Proposed comprehensive process for treatment of liquid industrial waste flows would prevent contamination by toxic effluents; ensure rational use of water, raw materials and energy inputs.

Author(s):  
M. Troubitsin ◽  
N. Volovicheva ◽  
L. Furda ◽  
N. Skrypnikov

Experimental studies of the influence of technological parameters of grinding alumina raw materials in a ball mill on the kinetics of the grinding process and the granulometric characteristics of activated alumina in the α-form have been carried out. It is found that the use of spherical grinding bodies leads to the formation of a specific four-modal granulometric composition with maxima: 0.5; 4.0; 50.0 and 400.0 microns, respectively. The disadvantage of using spherical grinding bodies is the uneven distribution of the introduced intensifier additive (PEG), which in turn causes adhesion of fine particles and the appearance of aggregates. This is especially pronounced at n = 100 rpm. When using grinding bodies of cylindrical shape, on the contrary, there is a tendency towards a bimodal nature of the distribution of particles with maxima in the regions of 0.4 and 4 μm, respectively, regardless of the rotation speed of the drum (n). The use of cylpebs does not provoke agglomeration of the fine particle fraction, which is observed in the case of spherical grinding bodies. When analyzing the kinetics of grinding alumina raw materials, two main stages of the process are identified. The first stage corresponds to the active fragmentation of large initial aggregates into constituent crystallites by the cleavage mechanism. The second stage corresponds to a change in the grinding mechanism from crushing to abrasion. It is found that carrying out the grinding process for 10 hours using cylindrical grinding bodies at n = 100 rpm and φ = 0.35 provides a high yield of the submicron fraction of the target product (1 μm) - up to 20 wt. %.


Author(s):  
Dmitry N. Samchenko ◽  
Gennadii М. Kochetov ◽  
Aleksey Vasiliev

The prospective for increasing of environmental safety level of industrial enterprises is considered as result of realization of energy- and resource saving technology for processing galvanic sludge by hydrophase ferritisation method. The possibility of obtaining Ni-Cu-Zn ferrites by processing of galvanic sludge based on of ferritization technology has been studied. Influence of different technological parameters and activation methods of the ferritisation process: thermal and electromagnetic pulse at temperatures of 75°С and 20°С, respectively, on qualitative and quantitative phase content of ferrite sediments has been experimentally determined. The method of electromagnetic pulse activation provides the appropriate degree of heavy metal ions extraction – 99.96%, and also has undeniable energy advantages over thermal, since energy consumption is reduced more than 60%. The efficiency of electromagnetic pulse discharges with magnetic induction amplitude of 0.298 T and a pulse frequency from 0.5 to 10 Hz to obtain environmentally friendly ferrite precipitates has been confirmed. The use of Ni-Cu-Zn ferrite powder for production of coatings that shield the electromagnetic rays in the ultrahigh frequency range is proposed. Obtained sediments have maximum content of crystalline ferromagnetic phases of ferrites – more than 93%. The proposed resource-saving ferritisation process prevents environmental pollution, ensures efficient and rational use of raw materials and energy in industry, as well as allows to obtain marketable products from industrial waste.


Author(s):  
O. Yu. Kichigina

At production of stainless steel expensive alloying elements, containing nickel, are used. To decrease the steel cost, substitution of nickel during steel alloying process by its oxides is an actual task. Results of analysis of thermodynamic and experimental studies of nickel reducing from its oxide presented, as well as methods of nickel oxide obtaining at manganese bearing complex raw materials enrichment and practice of its application during steel alloying. Technology of comprehensive processing of complex manganese-containing raw materials considered, including leaching and selective extraction out of the solution valuable components: manganese, nickel, iron, cobalt and copper. Based on theoretical and experiment studies, a possibility of substitution of metal nickel by concentrates, obtained as a result of hydrometallurgical enrichment, was confirmed. Optimal technological parameters, ensuring high degree of nickel recovery out of the initial raw materials were determined. It was established, that for direct steel alloying it is reasonable to add into the charge pellets, consisting of nickel concentrate and coke fines, that enables to reach the through nickel recovery at a level of 90%. The proposed method of alloying steel by nickel gives a possibility to decrease considerably steel cost at the expense of application of nickel concentrate, obtained out of tails of hydrometallurgical enrichment of manganese-bearing raw materials, which is much cheaper comparing with the metal nickel.


Batteries ◽  
2021 ◽  
Vol 7 (2) ◽  
pp. 29
Author(s):  
Leonard Kurz ◽  
Mojtaba Faryadras ◽  
Ines Klugius ◽  
Frederik Reichert ◽  
Andreas Scheibe ◽  
...  

Due to the increasing demand for battery electric vehicles (BEVs), the need for vehicle battery raw materials is increasing. The traction battery (TB) of an electric vehicle, usually a lithium-ion battery (LIB), represents the largest share of a BEV’s CO2 footprint. To reduce this carbon footprint sustainably and to keep the raw materials within a closed loop economy, suitable and efficient recycling processes are essential. In this life cycle assessment (LCA), the ecological performance of a waterjet-based direct recycling process with minimal use of resources and energy is evaluated; only the recycling process is considered, waste treatment and credits for by-products are not part of the analysis. Primary data from a performing recycling company were mainly used for the modelling. The study concludes that the recycling of 1 kg of TB is associated with a global warming potential (GWP) of 158 g CO2 equivalents (CO2e). Mechanical removal using a water jet was identified as the main driver of the recycling process, followed by an air purification system. Compared to conventional hydro- or pyrometallurgical processes, this waterjet-based recycling process could be attributed an 8 to 26 times lower GWP. With 10% and 20% reuse of recyclate in new cells, the GWP of TBs could be reduced by 4% and 8%, respectively. It has been shown that this recycling approach can be classified as environmentally friendly.


Author(s):  
A. Meliaschenya ◽  
I. Kaltovich ◽  
G. Pinchuk

The article presents the results of research on the determination of rational technological parameters for the production of culinary products using dry mixtures and emulsions based on animal raw materials for additive technologies. It was found that when making products using mixtures and emulsions based on broiler chicken meat, as well as a combination of broiler chicken meat and pork, pork and beef (ratio 1:1) rational height of the layer, which makes it possible to ensure stability and safety of the product shape (with a fixed diameter of the opening of the culinary syringe – 7 mm and the optimal length of the layer - 100 mm), is from 14–21 mm (with a layer width of 7 mm) and up to 133–154 mm (with a layer width of 98 mm), which allows for improved structural and mechanical (SSL – 1090.7–1099.9 Pa) and functional and technological indicators of these products (WHC – 92.7–97.5%). The rational sequence of application and the duration of chopping of the main and auxiliary raw materials for the manufacture of emulsions, the duration of preparation (3 minutes), the degree of hydration (1:2 – 1:3) and the temperature of water for the reduction of dry mixtures (60±1° C) were established, which made it possible to develop technological schemes for the production of culinary products using additive technologies.


Author(s):  
I. Kaltovich

The article presents the results of research on the determination of rational technological parameters for the production of chopped semi-products using emulsions from collagen-containing raw materials fermented by bacteria of the genus Lactobacillus. Water dosages are installed in the composition of chopped semi-finished products: 12% – with emulsions from pork skin and tails and 11% - with emulsion from connective tissue. Duration of ingredients mixing (5 minutes), sequence of raw materials laying during manufacture of articles, as well as duration of heat treatment of chopped semiproducts is determined: 25 minutes – during steaming (t = 95–100 °С), 20 minutes – during baking (t = 180 °C), 15 minutes – during frying (t = 110 °C), while recommended methods of bringing semifinished products to culinary readiness are steam treatment and baking, which allow for improved functional and technological (TUS – 79.3-81.8%, weight loss during heat treatment – 5.1–7.9%), structural and mechanical (PNS - 1413.9–1470.4 Pa) and organoleptic indicators (juiciness, appearance, consistency, taste, smell) of these products (9 points according to the 9-point system).


2021 ◽  
Vol 9 (16) ◽  
pp. 212-220
Author(s):  
Liubomyr Khomichak ◽  
◽  
Inha Kuznietsova ◽  
Svetlana Vysotska ◽  
Sergiy Tkachenko ◽  
...  

Introduction. Processing of grain raw material with influence on starch or albumens by application of heat treatment creates the variety of functional properties of a product and is perspective in the modern terms vital functions of man. Research methods and methods. The flour obtained from wheat of the Ascanian wheat and from wheat of the soft varieties: Sophia ("sweet wheat"), Blond (soft) and Chornobrova (enriched with micro- and macronutrients) were used in the study. Thermal modification of flour samples was carried out in a convective manner. The control sample for determining the quality indicators is obtained in industrial conditions, extruded wheat flour produced by LLC "AS groups, LTD". Research results. The obtained kinetic dependence shows the gradual loss of moisture standards with different speed which accordingly influences on duration of drying. The moisture content of the drying agent most affects the intensity at the initial stage of the constant drying rate. With an increase in the moisture content of the coolant, the period of constant drying increases and the amount of evaporated moisture increases during this period. With the subsequent removal of moisture from raw materials, the degree of influence of this parameter on the intensity decreases. The nature of the drying curves is the same and the recommended process for obtaining modified flour is the process duration of 300 minutes or 5 hours. It was determined microscopically, that the samples of dried wheat flour have a purpose and are partially destroyed by starch granules and amorphization of biocomposite materials. Based on the data on the kinetics of drying flour samples, the kinetic coefficients and values of the critical moisture content for drying wheat flour were calculated, which is 1.18-1.30 %. It was determined that for the sensorial indicators the obtained samples have indicators characteristic of the varietal characteristics of wheat, from which the flour was taken. In terms of physical and chemical parameters, the modified wheat flour samples are not inferior to the well-known industrial sample of extruded flour. Conclusions. Use of flour, obtained from the wheat with different correlation of amilose and amylopectin, positively influences on a technological process and allows to extend the assortment of modified starch products, and accordingly, food products. Kinetics of the convective drying standards of the flour is investigated. Researches showed that a it is physically modified flour obtained from the different sorts of the soft wheat is not inferior in quality to the extruded wheat flour.


2019 ◽  
Vol 19 (3) ◽  
pp. 226-229
Author(s):  
S.D. Bardasevska ◽  
I.M. Budzulyak ◽  
S.I. Budzulyak ◽  
B.I. Rachiy ◽  
R.V. Ilnytskyi ◽  
...  

The proposed method of synthesis of CQDs on the basis of nanoporous carbon obtained from plant raw materials. It is established that in the short-wave region a band is registered, which is due to the exciton mechanism of recombination, whereas in the long-wavelength region it is related to the state of defects. The kinetics of PL extinction is not strictly exponential, which most likely indicates the distributed nature of fading from individual emitters.


Author(s):  
V. Nelyubova ◽  
V. Babaev ◽  
Nataliya Alfimova ◽  
S. Usikov ◽  
O. Masanin

fiber concrete is one of the types of effective building materials that ensure the operational reliability of structures due to a set of unique properties. However, the maximum physicomechanical characteristics of this type of products are achieved only if the fiber is evenly distributed in the concrete matrix and the optimum ratio of raw materials is reached. In this connection, the aim of the work was to increase the production efficiency of fiber-reinforced concrete by optimizing the formulation and technological parameters of its manufacture. The optimal method of introducing the fiber into the concrete mix and the type of superplasticizer were previously determined, which allowed ensuring the maximum physicomechanical characteristics of the products. Optimization of prescription parameters was carried out using the method of mathematical planning of the experiment, where the amount of cement, superplasticizer and basalt fiber were varied. After processing the results, the dependences of the compressive strength on variable factors were obtained, which would allow to select the optimal dosages of raw materials for given mechanical characteristics of the products.


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