scholarly journals Improvement of environmental indicators of coal energy and agricultural production due to the integration and diversification of these industries

2020 ◽  
Vol 217 ◽  
pp. 04008
Author(s):  
Ekaterina Trushkova ◽  
Elena Omelchenko ◽  
Mikhail Sidelnikov

At present, there is extensive experience in the use of sulfuric acid ameliorant for soils with soda type of salinity. The authors found that as a result of using a weak solution of sulfuric acid on soils containing sodium and hydrocarbonates in their salt composition, their agrochemical characteristics are significantly improved. The article presents the results that show that the production of fertilizers and ameliorants from the waste of energy enterprises will increase their environmental safety. The use of sulfur oxides captured from the flue gases of coal-fired energy enterprises as a raw material for the production of sulfuric ameliorant will allow solving a double task: to reduce pollution of the zone of influence of enterprises and improve the condition of lands with soda salinization.

Author(s):  
I. A. Ilina ◽  
I. A. Machneva ◽  
E. S. Bakun

  The article is devoted to the study of the chemical composition, physical and thermal-pfysical characteristics of damp apple pomaces and the identifying patterns of influence of drying temperature the functional composition and gel-forming ability of pectin. The research is aimed at obtaining initial data for the subsequent calculation of the main technological, hydro-mechanical, thermal, structural and economic characteristics of devices for drying the plant raw materials, ensuring the environmental safety and high quality of pectin-containing raw materials, the reducing heat and energy costs. As a result of the study of the thermal characteristics of apple pomaces, the critical points (temperature conductivity – 16.5 x 10-8 m2/s, thermal conductivity – 0.28 W/m K, heat capacity – 1627 j/(kg K)) at a humidity of 56 % are determined, which characterizing the transition from the extraction of weakly bound moisture to the extraction of moisture with strong bonds (colloidal, adsorption). It was found that the pomaces obtained from apples of late ripening have a higher content of solids (21-23 %), soluble pectin and protopectin (2.5-4.5 %). Dried pomaces obtained from apple varieties of late ripening contain up to 25 % pectin, which allow us to recommend them as a source of raw materials for the production of pectin. The optimum modes of preliminary washing of raw materials are offered, allowing to the remove the ballast substances as much as possible. It is established that when the drying temperature increases, the destructive processes are catalyzed: the strength of the pectin jelly and the uronide component and the degree of pectin esterification are reduced. The optimum drying temperature of damp apple pomaces is 80 0C, at which the quality of pectin extracted from the dried raw materials is maintained as much as possible. It is shown that the most effective for the pectin production is a fraction with a particle size of 3-5 mm, which allow us to extract up to 71 % of pectin from raw materials.


2020 ◽  
Vol 10 (19) ◽  
pp. 6689
Author(s):  
Dmitriy Klepikov ◽  
Tereza Kudelova ◽  
Kristina Paushkina ◽  
Pavel Strizhak

Cylinder-shaped fuel pellets that were 3 mm in diameter and 3 mm in height, with a mass of 20 mg, were produced by compressing dry coal processing waste under the pressure of 5 MPa. The first group of pellets from coal dust with a particle size less than 140 µm did not contain any additives. The pellets of the second group of fuel compositions contained an oil-impregnated porous polymer material particle with a size of 0.5 mm in the central part of the experimental sample. The particle was surrounded by coal dust from all sides. The ratio of components was 90:10% for coal dust: polymer particle. The latter value almost completely corresponds to the fraction of oil in the fuel composition, since the mass of a porous polymer material particle is negligible. The third group of compositions was a 70:30% mixture of coal dust with wood sawdust with a particle size less than 45 µm, or 45–100, 100–200 and 200–500 µm. The ignition and combustion of single fuel pellets were studied under radiant heating in an air medium while varying the temperature from 800 to 1000 °C. The processes during the fuel combustion were recorded by a high-speed video camera, and the concentrations of the main anthropogenic emissions in flue gases were measured by a gas analyzer. The main characteristics were established—ignition delay times (2–8 s) and duration of burnout (40–90 s)—at different heating temperatures. A difference was established in the combustion mechanisms of the pellets, when adding various components to the fuel mixture composition. This has a direct influence on the induction period duration and combustion time, other conditions being equal, as well as on the concentration of nitrogen and sulfur oxides in the flue gases. Adding an oil-impregnated porous polymer particle to the fuel composition intensifies ignition and combustion, since the times of ignition delay and complete burnout of fuel pellets under threshold conditions decrease by 70%, whereas adding wood sawdust reduces the content of nitrogen and sulfur oxides in the flue gases by 30% and 25%, respectively.


2013 ◽  
Vol 789 ◽  
pp. 522-530 ◽  
Author(s):  
Latifa Hanum Lalasari ◽  
Rudi Subagja ◽  
Akhmad Herman Yuwono ◽  
Florentinus Firdiyono ◽  
Sri Harjanto ◽  
...  

lmenite (FeO.TiO2) ore from Bangka island-Indonesia is a potential raw material for synthesizing titanium dioxide (TiO2), which can be used further as pigmen and photocatalyst. The fabrication of TiO2 particles from ilmenite can be carried out through the solvent extraction using sulfuric acid route. Therefore, the solubility of the ilmenite ore in sulfuric acid environment is one of the key factors to obtain the desired TiO2 particles. The current research is aimed at comparing the solubility of pristine Bangka ilmenite ore with that of precedingly decomposed by sodium hidroxide (NaOH) in pressurized and atmospheric reflux reactors. The dissolution of both precursors was carried out in those reactors under various temperatures of 75, 100, 125, 150 and 175°C. The results showed that the optimum dilution was achieved at 150°C. The obtained recovery of ilmenite was 88.8 % for the pressurized reactor and 75.5% for the atmospheric reflux reactor. The solubility of titanium (Ti) element increased steadily to reach a recovery of 68% at 150°C and decreased significantly afterwards. It was also found that the increase of iron (Fe) element solubility was proportional to the increase of processing temperatures.


2012 ◽  
Vol 524-527 ◽  
pp. 965-968 ◽  
Author(s):  
Dan Liu ◽  
Shu Ming Wen ◽  
Yong Jun Xian ◽  
Hai Ying Shen ◽  
Shao Jun Bai ◽  
...  

A technology of “arsenic removing- sulfuric acid producing- residuals for ironmaking” is proposed for comprehensive utilization of pyrite with high content of arsenic. The effect of roasting temperature and time on arsenic removing was investigated. The arsenic removed residuals obtained under the optimal arsenic removed conditions, was used to be proceeded for sulphur volatilization test. The results demonstrate that final residuals with 63.53% of Fe can be used for steel industry. This technology can be used to fully utilize sulphur and produce high quality concentrate as iron-bearing feed for steel industry, which will help to reduce the pollution of arsenic and extend raw material sourcing for Chinese steel industry.


2021 ◽  
Vol 6 (1) ◽  
pp. 156-164
Author(s):  
Jessica E. Guzmán-Pérez ◽  
◽  
Oscar J. Salinas-Luna ◽  
Ernesto Favela-Torres ◽  
Nohemi López-Ramírez ◽  
...  

Water hyacinth (Eichhornia crassipes) is considered a pernicious herb in many parts of the world due to its rapid growth. However, for its high content of cellulose and hemicellulose, it could be considered as raw material to produce fermentable sugars. In this work, the effect of sulfuric acid concentration by thermochemical pretreatment and enzymatic hydrolysis on the release of sugars from water hyacinth was evaluated. Initially, the effect of the sulfuric acid concentration from 1.5 to 9% at 120 ºC was evaluated. With 1.5%, the release of reducing sugars was 160 milligrams of reducing sugars per gram of dry matter (mg red-sug/g dm). After the thermochemical pretreatment, the enzymatic hydrolysis with the cellulase complex (NS22086) allowed obtaining a reducing sugars concentration up to 317 mg red-sug/g dm. These thermochemical and enzymatic approaches to recover reducing sugars from water hyacinth is promising and should be evaluated for bioprocess using reducing sugars as the main source of carbon, such as bioethanol production.


Author(s):  
R. S. Durov ◽  
◽  
E. V. Varnakova ◽  
K. O. Kobzev ◽  
◽  
...  

Introduction. One of the most pressing socio-economic problems is the state of the environment, which affects the living conditions of many people. The article deals with the problem areas of the intersection of 20-ya Liniya street – Sholokhov Avenue in Rostov-on-Don. Problem Statement. The purpose of this paper is to improve environmental safety at the intersection of 20-ya Liniya street – Sholokhov Avenue in Rostov-on-Don by reducing emissions from road transport through the proposed measures to reorganize traffic on this section of the road network. Theoretical Part. The article provides an assessment of environmental and road safety on the road network section before applying the proposed measures. The measures are listed and justified that would help improve the conditions for road transport at the selected intersection and reduce emissions from road transport, which would improve environmental safety. The calculation of environmental indicators was made after the proposed measures to reduce NOx emissions by cars. Conclusion. The article analyzes the environmental indicators before and after the events, and then compares them. Based on the analysis and calculations, it is determined how much the proposed measures to optimize traffic will help reduce NOx emissions by cars.


2021 ◽  
Vol 41 (2) ◽  
pp. e87365
Author(s):  
Darwin Carranza Saavedra ◽  
Jorge Andrés Alvarado Nuñez ◽  
José Fernando Solanilla Duque ◽  
Claudia Patricia Valenzuela Real

In Colombia, approximately 855 840 tons of arracacha are produced each year. The unsalable postharvest arracacha root (Arracacia xanthorriza Bancroft) is not commercialized, mainly due to mechanical damage or small and misshapen roots. In this work, dry samples were characterized and subjected to two treatments: one using thermal hydrolysis, applying saturated steam at pressures of 0,1034 MPa, 0,2068 MPa, and 0,4137 MPa; and another one using hydrolysis with sulfuric acid in concentrations between 0,252,00 M. Then, the cake resulting from the hydrolysis and filtration process was enzymatically hydrolyzed (Liquozyme SC DS, Novozymes) at 1,5, 5 and 10 KNU/g (pH 6, 80 _C, 2 h). Fermentation inhibitors (acetic acid and furfural) were evaluated in the best pretreatment. The results showed that the treatment with sulfuric acid at 1,00 M (2 h) has high yields in reducing sugars added to enzymatic hydrolysis. The maximum level of fermentable carbohydrates per gram of dry sample (1,04 g/g) was also reached. Regarding the fermentation inhibitors of the reducing sugar, a higher concentration of acetic acid was found with a lower furfural content. Therefore, arracacha discards are a promising raw material to increase the supply of bioethanol.


Author(s):  
V.I. Lyashenko ◽  
F.F. Topolnyi ◽  
G.D. Kovalenko

Purpose. Improving the efficiency of leaching of metals from ore raw materials by justifying the parameters of underground mining and the introduction of integrated technology in combination with geotechnology, ensuring the rational use, protection of the subsurface and the environment during the development of reserves by combined geotechnological methods. Metology. The methods of generalization, analysis and evaluation of practical experience and scientific achievements in the field of geotechnology, theory and practice of explosive destruction of solid media, continuum mechanics, mathematical statistics, as well as research techniques of wave processes according to standard and new techniques of the leading experts of the world's advanced mining countries are described. Findings. The factors determining the leaching efficiency of metal ores, environmental and seismic safety are established and the parameters of the explosion are justified taking into account the size of an average linear piece of exploded ore mass, the area of an emanating surface and the seismic safety of protected objects (industrial buildings, residential buildings, the Ingul river underflow, Kropivnitsky, etc.). Originality. Recommended empirical dependence for the prediction of the oscillation speed on the reduced mass of charge per deceleration step in the explosive preparation of ore for underground leaching of metals for the field conditions of the form y = a ∙ b also the value of the permissible displacement rate of the soil at the base of the protected objects = 0.4 cm / s. Practical value. When non-conforming ores of deposits are involved in the production, their raw material base at operating mines can be increased 1.4–1.6 times. Keywords: mining technology, underground mining, metal leaching, environmental safety, efficiency.


2021 ◽  
Vol 4 ◽  
pp. 15-21
Author(s):  
M.O. Gordienko

THE SELECTION OF TECHNOLOGICAL BASIS OF DEEP PROCESSING OF COAL © M.O. Gordienko (State Enterprise "Ukrainian State Research Coal Chemical Institute (UHIN)", 61023, Kharkov, Vesnina st., 7, Ukraine) The article is devoted to the analysis of the possibility of expanding the raw material base of thermal energy, as well as meeting the demand for motor fuels and chemical products through the thermochemical processing of coal, the reserves of which are large enough and available for extraction and transportation. Moreover, in contrast to technologies such as methanization and liquefaction, the most promising type of deep processing of coal seems to be its gasification. This process is carried out in sealed devices of high power according to the technologies that have a long history of improvement on an industrial scale by the world's leading companies. It was emphasized that Ukraine has significant reserves of low-calorie coal (constantly expanding due to waste of coal preparation), the thermochemical processing of which can significantly expand the domestic energy base. The basic principles of classification and technological foundations of existing industrial and industrial research installations for gasification of coal and similar materials are given. The basic diagrams and main parameters of the existing installations, which carry out the gasification process at temperatures below the melting point of the mineral (ash-forming) components of the raw material, are described - Sasol Lurgi and SES Gasification Technology (SGT). Based on the data on the world experience in the operation of thermochemical coal processing units, it is shown that low-temperature (carried out at a temperature below the melting point of the mineral ashforming components) gasification of various types of non-coking coal with certain technological solutions can be no less effective than more complex and expensive high-temperature technologies. There are grounds for believing that the efficiency of gasification with ash removal in a solid state can be further increased by using some of the technological capabilities available in coke production. Keywords: brown coal, non-coking coals, thermochemical processing, gasification, efficiency, degree of carbon conversion, energy carriers, synthesis gas, environmental safety. Corresponding author M.O. Gordienko, е-mail: [email protected]


2016 ◽  
Vol 5 (6) ◽  
pp. 38-47
Author(s):  
Мануйлова ◽  
Natalia Manuylova ◽  
Булычев ◽  
Sergey Bulychev ◽  
Горбачев ◽  
...  

Problems related to a comprehensive assessment of construction materials’ environmental safety, taking into account stages of products’ complete life cycle have been considered. Approaches to determination of material’s safety and environmental record as environmental characteristics of the material, regardless of its use in a specific product, and without regard to processing technology have been described. It has been proposed to consider material’s safety and environmental record as the sum of three environmental safety factors for material’s life cycle stages: production of raw material and its potential environmental hazard; processing of raw material in the material; proper material from the standpoint of its environmental safety and effects on the human body. This criterion application allows compare the environmental properties both of cognate materials and dissimilar ones.


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