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Date submitted2024-03-29
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Date accepted2024-06-03
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Date published2024-07-04
Potential use of water treatment sludge for the reclamation of small-capacity sludge collectors
- Authors:
- Olga M. Guman
- Irina A. Antonova
In small settlements, collectors for the sludge produced during water treatment processes are small-sized and located in the vicinity of drinking water storage reservoirs or in coastal areas. Sludge removal is not economical. Besides, the relief depressions formed after sludge disposal are required to be reclaimed. In ore mining regions, where the main settlements of the Urals are located, sludge produced in water treatment has high contents of heavy metals typical of ore mining provinces. Consequently, places of sludge accumulation are potential sources of water pollution. The article discusses the possibility to mix sludge with slaked lime and local overburden with the help of special equipment. So far water treatment sludge in the region has been used to reclaim the surface of solid waste landfills by creating anaerobic conditions for waste decomposition. When placed inside the embankment dams as an independent object, sludge needs to be improved for the increase of its bearing capacity and the ability to bind heavy metals. The article aims at the substantiation of the composition and properties of the reclamation material made of the water treatment sludge mixed with local overburden and slaked lime (technosoil). For this reason the paper describes the composition of the sludge in a sludge collector, the composition and properties of the overburden rocks as a component of the mixtures with water treatment sludge, the composition and properties of the mixtures of water treatment sludge with overburden rocks and Ca(OH)2 as a component dewatering sludge and neutralizing toxicants. Furthermore, the research work provides the technology created for the optimal processing of the water treatment sludge in the process of the reclamation of a sludge collector. The research results and the experience obtained in reclamation of disturbed lands in the region have confirmed the possible use of technosoil for the reclamation of small-capacity sludge collectors. The analysis of the chemical composition and physical and mechanical properties of the mixtures under study has shown that the most economical and environmentally sound reclamation material is a mixture of water treatment sludge, loose overburden dump soils and Ca(OH)2 in a ratio of 60 : 30 : 10 %.
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Date submitted2022-08-10
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Date accepted2023-02-28
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Date published2024-02-29
Selection of the required number of circulating subs in a special assembly and investigation of their performance during drilling of radial branching channels by sectional positive displacement motors
The task of sludge removal to the surface during construction of directional and horizontal wells and strongly curved radial channels is relevant. For stable operation of technical system “Perfobore”, it is proposed to use a circulating sub that ensures efficient cleaning of channel wellbore from the drilled rock. Two schemes of technical system “Perfobore” are considered, consisting of two seven-meter coiled tubing, a positive displacement motor, a bit and one circulating sub in the first scheme and two subs in the second scheme. For each of the schemes CFD modeling was implemented to determine values of pressure and speed. It was found out that the use of two circulating subs in the assembly is more efficient. In order to confirm the numerical experiment, bench tests were carried out. It was determined that the designed circulating sub can eject up to 25 % of pumped drilling fluid. The bench tests of full-size technical system “Perfobore” for drilling 14-meter channels with two circulating subs showed that the axial load on positive displacement motor produced by hydraulic loader was 3000 N and pressure drop depending on flow rate was 1.5-2.0 MPa. This allows the motor to operate at maximum power.
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Date submitted2022-03-24
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Date accepted2022-07-21
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Date published2022-12-29
A probabilistic study on hole cleaning optimization
- Authors:
- Seyyed Shahab Tabatabaee Moradi
Hole cleaning is considered as one of the most important drilling fluid functions. An efficient hole cleaning ensures a reliable well drilling practice with minimum troublesome problems. In this study, two main steps of hole cleaning, i.e., cuttings removal from under the bit and cuttings transport to the surface are discussed based on the drilling data of a shale formation. The traditional models for optimization of each step are presented. As the models require variety of input data, which are usually subjected to some extent of errors and uncertainties, the output of the model is also an uncertain parameter. Using Monte Carlo simulation, a simple probabilistic study was conducted to quantify the certainty level of the obtained results. Based on the result of this study, it is shown that for the proposed well, a good hole cleaning is expected. However, a more reliable decision for further hole cleaning optimization should be made considering the results of uncertainty analysis.
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Date submitted2022-05-12
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Date accepted2022-09-15
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Date published2022-12-29
Problem solution analysis on finding the velocity distribution for laminar flow of a non-linear viscous flushing fluid in the annular space of a well
- Authors:
- Vasiliy I. Nikitin
Modern drilling fluids are non-linear viscous media with an initial shear stress. In classical scientific works on hydromechanical modeling of drilling fluids motion in pipes and annular channels the Shvedov – Bingham approximation and Ostwald – de Waale power-law model were used, which did not fully account for behavior of technological fluids in a wide range of shear rates. This article presents a numerical solution for a mathematical model of drilling fluid motion of the three-parameter Herschel – Bulkley rheological model in the annular space of the well. The Herschel – Bulkley model in the rheological equation takes into account the presence of initial shear stress and a tendency for viscosity to change with shear rate, which distinguishes it from the Ostwald – de Waale and Shvedov – Bingham models. The target function in solving the equation of motion is the velocity distribution in the radial direction of the upward flow of the flushing fluid. The analysis of obtained solution is based on the theory of velocity profile influence on quality of cuttings removal during wellbore cleaning. Due to peculiarities of mathematical statement of the task, which supposes necessity of differential equation of motion solution, Wolfram Mathematica computational software has been used as a calculation tool. The analysis of numerical solution allowed to draw conclusions about the possibility of its application in evaluation of velocity profile when drilling fluid moves in annular space of the well. The possibility for application of modified excess coefficient as a relative quantitative parameter for evaluation of velocity profile uniformity was substantiated.
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Date submitted2022-03-17
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Date accepted2022-06-20
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Date published2022-11-03
Assessment of collecting activity of physically sorbed reagents on the example of easily floatable coking coal sludge
- Authors:
- Sergey A. Kondratev
- Tatyana A. Khamzina
The article presents one of the new approaches to theoretical assessment of collecting ability of reagents. The efficiency of reagents-collectors with different chemical composition used for flotation of coking coals was studied. A comparative assessment of the flotation activity of kerosene, mineral oil, thermal gas oil, KETGOL and FLOTEK is given. The criteria of collecting activity of the above reagents-collectors for coal sludge flotation were specified. A correlation was established between the indicators of coal sludge flotation by the above reagents and their physical parameters. It is shown that the rate of spreading over water surface can characterize the flotation activity of reagents. Based on dependence of the collecting activity of a reagent on its rate of spreading along the “gas – liquid” interface and surface pressure, the main approaches to determining the structure and composition of molecules of an effective flotation collector can be determined. A new concept of the function performed by a physically sorbed collector in the elementary act of flotation and a criterion for the flotation activity of reagents used in coal sludge beneficiation are proposed. It is shown that the collector used in coal flotation, in addition to hydrophobizing the surface of the extracted particles, should reduce the induction time and remove the kinetic constraint on formation of a flotation aggregate.
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Date submitted2021-02-24
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Date accepted2022-04-06
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Date published2022-07-13
Study of the kinetics of the process of producing pellets from red mud in a hydrogen flow
The reduction kinetics of serial phase transitions of iron oxides during reduction to a metallized state with different modes of technical hydrogen supply has been studied and substantiated. The results of the pellets formation when 3-5 % molasses is added to the red mud as a binding reagent are presented. The dependences of the reduction rate of iron oxides on the hydrogen flow rate are obtained. Based on the results of the experiments, a kinetic model was constructed, and with the help of X-ray phase and spectral analysis, it was proved that the agglomerates formed after heat treatment received high strength due to the adhesion of reduced iron particles with red mud particles. The use of a new type of charge materials in melting units will reduce the amount of emissions and dust fractions, as well as increase the metal yield.
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Date submitted2019-01-16
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Date accepted2019-03-07
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Date published2019-06-25
Sintered sorbent utilization for H2S removal from industrial flue gas in the process of smelter slag granulation
- Authors:
- A. B. Lebedev
- V. A. Utkov
- A. A. Khalifa
Authors suggest removing hydrogen sulfide from the hot industrial gas at temperatures 200-300 °C and its subsequent interaction with Fe 2 O 3 . For this purpose the following sorbents have been proposed: a mixture of iron oxide and fly ash; iron oxide and pumice; different samples of red mud (bauxite treatment residues containing iron oxide). To prevent dusting and loss of absorbing capacity, the sorbents were shaped into porous granules with other metallic oxides. Materials utilized in the study were obtained the following way: mixing of Fe 2 O 3 with fly ash; sintering of the mixture with red mud. The blend contains aluminum oxide and silica, which can act as matrix shapers, alkali oxides and fluxing agents that reduce the temperature during metal sintering. After the samples had been saturated with sulfur, they were positioned in a venting reservoir, where under the temperature 600-700 °C desorption to the initial state occurred by means of passing an air flow through the sorbent layer. In the process of this operation, sulfur dioxide was released and reactive metal oxides re-emerged. Desorption also generated a small amount of elemental sulfur and sulfuric acid. Absorbing capacity was assessed at higher temperatures, efficiency of H 2 S removal reached 95-99.9 %. Proposed technology of air cleaning is recommended to use in metallurgic processes with elevated atmospheric pollution, e.g. granulation of melted blast-furnace slag.
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Date submitted2018-09-13
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Date accepted2018-11-09
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Date published2019-02-22
Lignin sludge application for for-est land reclamation: feasibility assessment
- Authors:
- M. A. Pashkevich
- T. A. Petrova
- E. Rudzisha
The article analyses waste generation of pulp and paper industry in North-Western Russia. The environmental impact of waste storage facilities of the pulp and paper mill was assessed, the need for utilization of lignin sludge was justified. In North-Western Russia, 1.21 million hectares of disturbed areas are in need for reclamation; they are abandoned quarries and lands alienated for pipeline and road construction. The suitability of lignin sludge for preparation of artificial fertile soils for reclamation purposes is estimated. For this purpose, experiments were carried out to create an artificial mixture with different ratios of lignin sludge and soil, to detect the maldevelopment of several plant species grown on various compositions of lignin sludge and soils. It was revealed that lignin sludge as an organic additive to soils is not toxic to vegetation and living organisms, allowing improving fertility of artificial soils.
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Date submitted2017-11-20
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Date accepted2018-01-09
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Date published2018-04-24
Sulfidization of silver-polymetallic ores of «Goltsovoe» deposit for decreasing loss of silver in mill tailings
- Authors:
- L. V. Shumilova
- O. S. Kostikova
The results of laboratory studies of flotation concentration of silver-polymetallic ores of the Goltsovoe deposit at the Omsukchansk concentrator are presented. The results of sieve analysis of mill tailings of the experimental sample of MTP N 101 (N 7577-i) are described. They indicate that a large amount of silver (123 g/t) is lost in the size class – 0.040 mm (yield 50.25 %). According to the results of mineralogical analysis, it is established that the major losses of noble metal are associated with its fine impregnation in oxides, sulfides and silicate rocks. The main silver-bearing minerals are acanthite, polybasite and kustelite (class – 0.040 mm). Experimental studies were carried out in two stages. The purpose of the first stage is to determine the influence of grinding fineness in flotation feed (for a finished class content of 0.074 mm in the range of 60-95 %) for silver recovery at different amounts of butyl potassium xanthate (50, 150, 300 g/t). The purpose of the second stage is to evaluate the effectiveness of sulfidization at different consumption of sodium sulfide Na 2 S·9H 2 O (50, 150, 200, 450, 750 g/t – 1 % aqueous solution) under the conditions of the optimal reagent mode established in the first stage of the study. The results of experiments to determine the optimum grinding fineness and studies on the enrichment of silver-polymetallic ore with the use of sodium sulfide as a sulfidizer are presented. The efficiency of the sulfidization process is estimated. The following experimental dependencies of silver recovery are established: on the degree of grinding and consumption of butyl potassium xanthate; on variations of grinding fineness and the consumption of sodium sulphide (with a consumption of butyl xanthate 150 g/t); and on grinding fineness at optimum consumption of sodium sulfide 150 g/t and butyl potassium xanthate 300 g/t. A comparative evaluation of dependence of silver recovery index from the degree of grinding fineness before and after introduction of sodium sulphide (collecting agent consumption of 150 g/t) is given. T\
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Date submitted2015-10-12
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Date accepted2015-12-26
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Date published2016-08-22
Use of various types of carbon-containing raw materials to produce thermal energy
- Authors:
- V. B. Kuskov
- V. Yu. Bazhin
Many types of carbon-containing organic compounds and all possible carbon-containing products or wastes in low demand can be used to produce thermal energy. A technology has been developed for producing highly flammable briquettes on the basis of bituminous coal. These briquettes have a special incendiary layer. It is easily ignites from low energy heat sources (e.g. matches), and then flame spreads to the rest of briquette. Use of coal slacks and paper wastes as carbon-containing components playing the role of binders provides an opportunity to get a fuel briquette easy in terms of production and plain in composition while at the same time dispose of coal and paper wastes. Such briquettes may also have a special incendiary layer. Technology for fuel briquettes production from wood and slate wastes employed no binding agents, as wood products acted as binders. Thus technologies have been developed to produce fuel briquettes from various carbon-containing materials in low demand. The briquettes are intended for household boilers, fireplaces, different ovens in order to cook food, heat residential and utility premises, cabins, etc.
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Date submitted2015-08-27
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Date accepted2015-10-05
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Date published2016-04-22
Processing of alumina production red mud with recovery of scandium concentrate
The chemical and technological principles of scandium recovery from red mud of alumina production with the use of flue gases from sintering furnaces have been developed. The optimal conditions of hydrochemical processes of successive removal of impurities for the production of scandium concentrate with simultaneous obtaining of titanium-containing product have been worked out on a pilot plant.
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Date submitted2015-07-27
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Date accepted2015-09-17
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Date published2016-02-24
Electroextraction of cobalt from sulfate-chloride and sulfate solutions of cobalt and manganese in static conditions
- Authors:
- L. P. Khomenko
- L. A. Voropanova
The dependence of the results of electroextraction cobalt and manganese from aqueous solutions of their sulphate and chloride-sulfate solutions under static conditions was investigated. According to the results of current efficiency and specific energy consumption it has been found that the electrowinning of cobalt from aqueous solutions of cobalt and manganese in static conditions using a titanium cathode should be carried out at low concentration of manganese from sulphate-chloride solution without partitions and from sulphate solutions both without and with the perforated partitions separating the electrolytic cell into cathode and anode space.
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Date submitted2009-08-23
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Date accepted2009-10-05
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Date published2010-02-01
Developing a rational technology of utilization оf bio and oil slimes of the Kinef Ltd by an extraction оf useful components
- Authors:
- K. A. Moiseeva
The paper deal with the problem of developing a rational technology of slime and silt recycling for company «KINEF», which nowadays is one of the leading companies in Russia in it area. Therefore the question of soil-waste utilization is one of the major issues to adress for this organisation. During the reaserch samples of soil waste were taken and analyised, which helped to work out a complite technology of recycling. Special attention is paid to the necessity of extraction of the useful components.
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Date submitted2009-08-16
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Date accepted2009-10-02
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Date published2010-02-01
Study of the opening of copper presence electrolytic slimes of the copper production
- Authors:
- S. A. Modestova
The methods of processing the electrolytic slimes of copper production are examined. The process of the autoclave oxidizing leaching of copper slime is investigated. It is established that the autoclave opening ensures the selective transfer into the solution of nonferrous metals and concentration in the cakes of the leaching of noble metals.