scholarly journals Metallurgical processing of converter slag

2021 ◽  
Vol 318 (3) ◽  
pp. 35-42
Author(s):  
S.M. Tleugabulov ◽  
◽  
N.B. Aitkenov ◽  
G.G. Zhabalova ◽  
A.G. Belichko ◽  
...  
Keyword(s):  
Industrial Waste ◽  
Converter Slag ◽  
Experimental Studies ◽  
Raw Material ◽  
Production Waste ◽  
Gas Purification ◽  
High Concentration ◽  
High Quality ◽  
Quality Steel ◽  
Technical Requirements

Converter slurries at modern metallurgical plants represent a significant part of metal-containing industrial waste with a high concentration of iron. Currently, there is a problem of their utilization and use as raw materials for metallurgy. The purpose of this work is to study the processes of briquetting and recovery of briquetted products, based on a mixture of converter slurries of gas purification and converter slags. When performing experimental studies on the preparation of sludge briquettes from a mixture of converter sludge of gas purification and converter slag, their metallization and reduction melting in laboratory conditions, the optimal composition of the components of the mixture of converter slag and gas purification sludge was determined by the percentage of iron, which is appropriate for use as a raw material for steel smelting. Experimental studies on the preparation of sludge-coal mixtures from dispersed metal-containing and carbon-containing industrial waste with stoichiometric coal consumption for the recovery of extracted metals have proved the possibility of obtaining sludge-coal briquettes, which are further subjected to metallization and reduction melting. Sequential processing of dispersed production waste, namely drying, metallization and reduction melting, allowed us to obtain at the final stage a metal sample that corresponds to high-quality steel in its composition. Based on the analysis of the results of experimental studies, the technology of reducing melting of metal-containing waste has been developed. As a result of the implementation of the technology, high-quality steels and alloys can be obtained without carburizing the metal, bypassing the production stages of cast iron and high-carbon alloys. The content of harmful impurities of sulfur and phosphorus meets the technical requirements of high-quality steel. The proposed technology for processing slag and sludge from oxygen-converter production will reduce the volume of accumulated production waste.

scholarly journals EXPERIMENTAL RESEARCH OF CHARACTERISTICS OF CRUSHERS WITH CYCLOIDAL MOTION OF WORKING BODIES

2018 ◽  
Vol 15 (30) ◽  
pp. 627-639
Author(s):  
O. Zh. RABAT ◽  
A. N. SALMANOVA
Keyword(s):  
Experimental Studies ◽  
Raw Material ◽  
Crushed Stone ◽  
Sieve Analysis ◽  
High Quality ◽  
Working Space ◽  
Stone Material ◽  
The Republic ◽  
Working Bodies ◽  
Flat Flow

The use of different crushers to obtain the required size of the stone material. This work presents experimental studies of the characteristics of a crusher with a complex movement of working organs. The objectives of the study are, a sieve analysis of the obtained product (crushed stone) and the determination of the optimal speed of the working bodies (rolls) to obtain high-quality cubic shape crushed stone. In the experiment, the raw material is fed into the working space (into the crushing chamber) through the hopper and moves by a flat flow between the rollers. The edges of the rolls roll symmetrically from two sides to the flow of material, approaching in the area of the crushing zone and diverging in the region of the unloading zone. The authors determined the optimal rolls for obtaining high-quality cubiform crushed stone (over 80%). As a result, of the research, it was established that the grain composition of the fraction is within the standard of the Republic of Kazakhstan 1225-2003 t.3 – is obtained cubiform crushed stone, with an rotational speed of rolls of 100-120 rpm.

scholarly journals The Use of Heat From the Incineration of Municipal Solid Waste for Processing of Phosphogypsum

2018 ◽  
Vol 7 (4.3) ◽  
pp. 344 ◽  
Author(s):  
Olga Krot ◽  
Varvara Vinnichenko ◽  
. .
Keyword(s):  
Phosphoric Acid ◽  
Building Material ◽  
Acid Production ◽  
Industrial Waste ◽  
Phosphate Rock ◽  
Operating Temperature ◽  
Experimental Studies ◽  
Efficient Utilization ◽  
High Quality ◽  
Global Issues

Municipal landfills and open dumps with industrial waste are global issues which impact on the environment and on the health of populations. The production of phosphoric acid from natural phosphate rock gives rise to an industrial by-product called phosphogypsum, containing mainly dihydrated gypsum. Five tons of phosphogypsum are generated per ton of phosphoric acid production. The technology of roasting of phosphogypsum in a dehydrator, which is a mine, has been described in the article. Such reprocessing of the waste makes it possible to obtain a ready-made high-quality building material. The development of a complex that processes wet and highly adhesive phosphogypsum using the heat of combustion of alternative fuel (municipal waste) is consistent with the synergetic concept of environmentally efficient utilization. Experimental studies identify the most rational parameters of the dehydrator, namely, its operating temperature, have been conducted. The temperature of a heat carrier (air) varied from175 °Cto350 °Cin the experiment.  

Effect of Fluidized Bed Ash on the Thermodynamic Stability of Hydraulic Binders

2017 ◽  
Vol 908 ◽  
pp. 21-25
Author(s):  
Karel Kulísek ◽  
Dominik Gazdič ◽  
Karel Dvořák
Keyword(s):  
Fly Ash ◽  
Fluidized Bed ◽  
Thermodynamic Stability ◽  
Industrial Waste ◽  
Raw Material ◽  
Cement Stone ◽  
Material Base ◽  
Volume Changes ◽  
High Quality ◽  
Secondary Raw Material

Fluidized bed ash, which is the youngest industrial waste can be considered on the basis of research, a high-quality secondary raw material base which can be easily used in the production of Portland cements and, in general, other hydraulic binders. Regarding the direct effect of anhydrite on the course of hydrating mixed cement with the fluidized fly ash and the consequent behaviour of the originated cement stone, its reaction with clinker materials on the mentioned Aft (Al2O3–Fe2O3-–tri) phase is clear. The creation of AFt phases, if they originate additionally, due to their morphology, is accompanied by significant volume changes which may lead to deformation up to the destruction of the cement stone. Some foreign publications show the possibility of the transformation of this thermo-dynamically unstable mineral into the further mineral from the group AFt phase, which is thaumasite, Ca3Si (CO3)(SO4)(OH)6.12H2O.

TECHNOLOGICAL ASPECTS OF HIGH QUALITY RAW MATERIAL OBTAINING FOR PECTIN PRODUCTION

1970 ◽  
pp. 47-50
Author(s):  
I. A. Ilina ◽  
I. A. Machneva ◽  
E. S. Bakun
Keyword(s):  
Raw Materials ◽  
Thermal Characteristics ◽  
Environmental Safety ◽  
Raw Material ◽  
High Quality ◽  
Temperature Conductivity ◽  
Drying Temperature ◽  
Plant Raw Materials ◽  
Gel Forming Ability

  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.

Applications of Bentonite to Soil Decontamination

2018 ◽  
Vol 69 (7) ◽  
pp. 1695-1698
Author(s):  
Marin Rusanescu ◽  
Carmen Otilia Rusanescu ◽  
Gheorghe Voicu ◽  
Mihaela Begea
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Laboratory Experiments ◽  
Experimental Studies ◽  
Heavy Metal Concentration ◽  
Polluted Soil ◽  
Raw Material ◽  
Soil Decontamination ◽  
Metal Retention ◽  
Removal Of Heavy Metals

A calcium bentonite from Orasu Nou deposit (Satu Mare Romania) was used as raw material. We have conducted laboratory experiments to determine the influence of bentonite on the degree of heavy metal retention. It has been observed that the rate of retention increases as the heavy metal concentration decreases. Experimental studies have been carried out on metal retention ( Zn) in bentonite. In this paper, we realized laboratory experiments for determining the influence of metal (Zn) on the growth and development of two types of plants (Pelargonium domesticum and Kalanchoe) and the effect of bentonite on the absorption of pollutants. These flowers were planted in unpolluted soil, in heavy metal polluted soil and in heavy metal polluted soil to which bentonite was added to observe the positive effect of bentonite. It has been noticed that the flowers planted in unpolluted soil and polluted with heavy metals to which bentonite has been added, the flowers have flourished, the leaves are still green and the plants whose soils have been polluted with heavy metals began to dry after 6 days, three weeks have yellowish leaves and flowers have dried. Experiments have demonstrated the essential role of bentonite for the removal of heavy metals polluted soil.

scholarly journals A study on highly concentrated lactic acid and the synthesis of lactide from its solution

2021 ◽  
pp. 174751982110210
Author(s):  
Xiaolong Xu ◽  
Lijuan Liu
Keyword(s):  
Lactic Acid ◽  
Acid Solution ◽  
Concentration Distribution ◽  
Raw Material ◽  
High Concentration ◽  
Composition Distribution ◽  
Lactic Acid Solution ◽  
H Nmr ◽  
Back Titration ◽  
Condensed Water

Lactic acid is an important platform compound used as raw material for the production of lactide and polylactic acid. However, its concentration and composition distribution are not as simple as those of common compounds. In this work, the mass concentration distribution of highly concentrated lactic acid is determined by back titration. The components of highly concentrated lactic acid, crude lactide, and polymer after the reaction are analyzed by HPLC. Different concentrations of lactic acid solution were prepared for the synthesis of lactide and its content in the product was determined by 1H NMR analysis. We found that lactide is more easily produced from high-concentration lactic acid solution with which the condensed water is easier to release. Hence, the removal of condensed water is crucial to the formation of lactide, although it is not directly formed by esterification of two molecules of lactic acid.

Experimental studies on resistance characteristics of high concentration red mud in pipeline transport

2008 ◽  
Vol 14 (1) ◽  
pp. 157-161
Author(s):  
Xing Wang ◽  
Yuan-yuan Qu ◽  
Wei-wei Hu ◽  
Jie Chen ◽  
Xue-yi Zhao ◽  
...  
Keyword(s):  
Red Mud ◽  
Experimental Studies ◽  
Pipeline Transport ◽  
High Concentration

scholarly journals Phytoremediation Potential of Vetiver System Technology for Improving the Quality of Palm Oil Mill Effluent

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Negisa Darajeh ◽  
Azni Idris ◽  
Paul Truong ◽  
Astimar Abdul Aziz ◽  
Rosenani Abu Bakar ◽  
...  
Keyword(s):  
Palm Oil ◽  
Oxygen Demand ◽  
Raw Material ◽  
Biofuel Production ◽  
Palm Oil Mill Effluent ◽  
System Technology ◽  
High Concentration ◽  
Low Concentration ◽  
Control Sets ◽  
Palm Oil Mill

Palm oil mill effluent (POME), a pollutant produced by the palm oil industry, was treated by the Vetiver system technology (VST). This technology was applied for the first time to treat POME in order to decrease biochemical oxygen demand (BOD) and chemical oxygen demand (COD). In this study, two different concentrations of POME (low and high) were treated with Vetiver plants for 2 weeks. The results showed that Vetiver was able to reduce the BOD up to 90% in low concentration POME and 60% in high concentration POME, while control sets (without plant) only was able to reduce 15% of BOD. The COD reduction was 94% in low concentration POME and 39% in high concentration POME, while control just shows reduction of 12%. Morphologically, maximum root and shoot lengths were 70 cm, the number of tillers and leaves was 344 and 86, and biomass production was 4.1 kg m−2. These results showed that VST was effective in reducing BOD and COD in POME. The treatment in low concentration was superior to the high concentration. Furthermore, biomass of plant can be considered as a promising raw material for biofuel production while high amount of biomass was generated in low concentration of POME.

scholarly journals Antioxidant properties, quantification and stability of betalains from pitaya (Hylocereus undatus) peel

2014 ◽  
Vol 45 (2) ◽  
pp. 323-328 ◽  
Author(s):  
Fernanda Robert de Mello ◽  
Claudia Bernardo ◽  
Caroline Odebrecht Dias ◽  
Luciano Gonzaga ◽  
Edna Regina Amante ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Phenolic Compounds ◽  
Antioxidant Properties ◽  
Raw Material ◽  
High Concentration ◽  
Natural Colorant ◽  
Wide Ph Range ◽  
Hylocereus Undatus ◽  
Ph Range ◽  
Promising Source

Pitaya peel can be used as a raw material for betalains extraction. The aim of this research was to quantify phenolic compounds, antioxidant activity and betalains on pitaya peel. Furthermore, evaluate the betalains stability against various pH conditions and exposure time of heating. The results showed that pitaya peel contains phenolic compounds and presented antioxidant activity. Moreover it showed high concentration of betalains (101.04mg equivalent to betanin. 100g-1) which were stable over a wide pH range (3.2 - 7.0) and were resistant to heating (100oC) up to 10 minutes at pH range from 3.7 to 5.5. Therefore, pitaya peel is a promising source of betalains which can be applied as a natural colorant for food.

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