Modern Approaches to Efficient Use of Mn-Containing Raw Material in Steel Production

2015 ◽  
Vol 770 ◽  
pp. 8-13 ◽  
Author(s):  
O.I. Nokhrina ◽  
I.D. Rozhihina ◽  
I.E. Proshunin ◽  
I.E. Hodosov ◽  
V.G. Osipova

A flow diagram of complex concentration of polymetallic manganese-containing ores of the Altai-Sayan new deposits is developed. Process conditions of recovery of valuable components by chemical concentration are determined. The results of use of high-quality concentrates of manganese, ferrum and nickel at manufacture of steel and metallic manganese are included.

Processes ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 402
Author(s):  
Marcus Kirschen ◽  
Thomas Hay ◽  
Thomas Echterhof

Steelmaking based on direct reduced iron (DRI, and its compacted derivative hot briquetted iron, HBI) is an anticipated important global alternative to current steel production based on FeOx reduction in blast furnaces due to its lower specific CO2 emission. The majority of DRI is melted and refined in the electric arc furnace with different process conditions compared to the melting of steel scrap due to its raw material composition being rather different. We provide data and analysis of slag composition of DRI charges vs. steel scrap charges for 16 industrial electric arc furnaces (EAFs). Suggestions for optimized slag operation and resulting process improvements of DRI melting in the EAF are given. A dynamic mass and energy model of the DRI melting in the EAF is introduced to illustrate the implications of the adapted slag operation on the EAF process with DRI charges.


2008 ◽  
Vol 3 (1) ◽  
Author(s):  
Martin Kranert ◽  
Gerold Hafner ◽  
Ingrid Berkner ◽  
Ertugrul Erdin

While composting of separate collected bio-waste is currently undergoing a renaissance in Germany, sewage sludge composting offers as well the possibility to produce a hygienic soil conditioner and/or secondary raw material fertilizer. This alternative is increasingly interesting, especially to bring back nutrients and organic substances into soils. This paper explains the essential reasons for composting, shows the process conditions and the different composting processes used currently in Germany. The discussion about the heavy metal problem and the production of a high quality fair marketable product leads to the necessity of a quality assurance system, which has been proven to be effective for bio-waste composting in Germany. The necessary boundary conditions and demands for such a quality assurance system for sewage sludge are presented.


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.


Foods ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 788
Author(s):  
João Paulo de Lima Ferreira ◽  
Alexandre José de Melo Queiroz ◽  
Rossana Maria Feitosa de Figueirêdo ◽  
Wilton Pereira da Silva ◽  
Josivanda Palmeira Gomes ◽  
...  

The residue generated from the processing of Tacinga inamoena (cumbeba) fruit pulp represents a large amount of material that is discarded without proper application. Despite that, it is a raw material that is source of ascorbic acid, carotenoids and phenolic compounds, which are valued in nutraceutical diets for allegedly combating free radicals generated in metabolism. This research paper presents a study focused on the mathematical modeling of drying kinetics and the effect of the process on the level of bioactive of cumbeba residue. The experiments of cumbeba residue drying (untreated or whole residue (WR), crushed residue (CR) and residue in the form of foam (FR)) were carried out in a fixed-bed dryer at four air temperatures (50, 60, 70 and 80 °C). Effective water diffusivity (Deff) was determined by the inverse method and its dependence on temperature was described by an Arrhenius-type equation. It was observed that, regardless of the type of pretreatment, the increase in air temperature resulted in higher rate of water removal. The Midilli model showed better simulation of cumbeba residue drying kinetics than the other models tested within the experimental temperature range studied. Effective water diffusivity (Deff) ranged from 6.4890 to 11.1900 × 10−6 m2/s, 2.9285 to 12.754 × 10−9 m2/s and 1.5393 × 10−8 to 12.4270 × 10−6 m2/s with activation energy of 22.3078, 46.7115 and 58.0736 kJ/mol within the temperature range of 50–80 °C obtained for the whole cumbeba, crushed cumbeba and cumbeba residue in the form of foam, respectively. In relation to bioactive compounds, it was observed that for a fixed temperature the whole residue had higher retention of bioactive compounds, especially phenolic compounds, whereas the crushed residue and the residue in the form of foam had intermediate and lower levels, respectively. This study provides evidence that cumbeba residue in its whole form can be used for the recovery of natural antioxidant bioactive compounds, mainly phenolic compounds, with the possibility of application in the food and pharmaceutical industries.


Author(s):  
Zhou J ◽  
◽  
Dong Y ◽  
Ma Y ◽  
Zhang T ◽  
...  

Graphene Quantum Dots (GQDs) have been prepared by oxidationhydrothermal reaction, using ball-milling graphite as the starting materials. The prepared GQDs are endowed with excellent luminescence properties, with the optimum emission of 320nm. Blue photoluminescent emitted from the GQDs under ultraviolet light. The GQDs are ~3nm in width and 0.5~2 nm in thickness, revealed by high-resolution transmission electron microscopy and atomic force microscopy. In addition, Fourier transform infrared spectrum evidences the existence of carbonyl and hydroxyl groups, meaning GQDs can be dispersed in water easily and used in cellar imaging, and blue area inside L929 cells were clearly observed under the fluorescence microscope. Both low price of raw material and simple prepared method contribute to the high quality GQDs widespread application in future.


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.


Author(s):  
Rahmi Karolina ◽  
◽  
M.A.P Handana ◽  
Rahmat Jatmikanto ◽  
◽  
...  

A The current environmental problem is regarding to CO2 gas emissions from cement production and the presence of hazardous material waste (B3) from steel production. One solution for that problem is by applying slag cement as a substitute for type I portland cement in concrete mix to create a high quality concrete that is environmentally friendly with a high durability and initial strength. This research aimed to compare a high quality concrete made from slag cement and a high quality concrete with conventional mixture. The slag cement used was obtained from PT. Indocement Indonesia. It is coupled with the use of Master Ease 3029 superplasticizer. The results showed that from the samples of concrete of 3, 7, 14, 28, 56 and 90 days of age, the maximum absorption value of normal concrete occurs at the age of 90 days with acid water curing of 1.57%. While the maximum absorption value of slag cement concrete occurs at the same age with acid water curing of 1.50%. The curing of normal concrete with water at 56 days of age has the largest compressive strength from all. It is also found that slag cement concrete has higher maximum compressive strength than that of normal concrete with acid water curing at 56 days of curing.


2019 ◽  
Vol 9 (1) ◽  
pp. 1
Author(s):  
Sovian Aritonang ◽  
Jupriyanto Jupriyanto ◽  
Riyadi Juhana

<p>The number of iron sand reserves is mostly spread in the coastal waters of Indonesia, from the coast of Sumatra, the southern of Java to Bali, the beaches of Sulawesi, beaches in East Nusa Tenggara (NTT), and the northern coast of Papua. Total reserves for ore are 173,810,612 tons and metal as much as 25,412,652.62 tons. But its utilization was not optimal because PT. Krakatau Steel, and PT. Krakatau Posco has produced steel plates only 24,000 to 36,000 tons per year. While the need for steel plates for the shipping industry each year requires 900,000 tons per year. With the need for raw material for steel plates in the form of iron sponges with Fe ≥ 60%, PT. Krakatau Steel is still imported from abroad. The proof is PT. Krakatau Steel before and during the year 2000 still imported Iron Ore Pellets from the countries of Sweden, Chille and Brazil for 3,500,000 tons per year. This condition is the cause of the national steel industry unable to compete with the foreign steel industry because imported raw materials are subject to import duties. This is an opportunity to build a steel raw material company because all this time the steel raw material industry in Indonesia has only two companies. This condition encourages the manufacture of iron sponges, with the process of making iron sponges with technology adapted to installed production capacity. This study analysed the manufacture of iron sponges using Cipatujah iron sand, as raw material for the manufacture of iron sponges, with the results obtained in the form of iron sponges with the highest levels of Fe ≥60.44%. This can be used for the purposes of raw materials for steel making PT. Krakatau Steel (PT. KS), because so far PT. KS claims that Fe &lt;60% local sponge iron products. This can encourage the independence of steel raw materials, which impacts on the independence of the defence industry. But the government must also protect and prioritize steel raw materials for national production for national steel production. With the national government steel industry, the consortium of vendors supplying raw material (iron sponge) to maintain the quality and supply of continuous sponge iron.</p><p><strong>Keywords</strong>: iron sand, iron pellet, iron sponge</p>


2021 ◽  
Vol 5 (2) ◽  
pp. 714-722
Author(s):  
Noverita Sprinse Vinolina ◽  
Antonio Marro Sipayung ◽  
Dardanila ◽  
Sondang Pintauli

This program is conducted to assist Siponjot Village while empowering the people of Siponjot Village to be able to utilize and maximize the benefit of the village forest. Village forest might support the availability of raw materials required for making musical instruments, such as high quality of wood, including how to process wood waste from making musical instruments to be used as creative souvenirs and improve the economic value. The raw material for production determined its results of the production of wood-based musical instruments. Thus, in order to produce a high quality tanginang, hasapi, and gondang, which previously began to be produced by arts crafts in the Sitangkubang area of ​​Siponjot Village, a high quality of raw materials is needed. The community service team surveyed the location of planting seeds for village forest restoration, provided socialization related to the importance of village forest cultivation and the suitability of the Siponjot Village area for the cultivation of these plants. Village forest restoration aims to maintain the beauty and beauty of the village. Implementation of village reforestation activities starting from socializing forest tourism and the strength of village forests to the community, followed by a discussion about village forest management and its economic benefits. Handover of a thousand units of forest plant seedlings given to the villagers of Siponjot as part of the forest restoration program in the area.


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