Modification of Technological Properties of Laboratory Premixes

2018 ◽  
Vol 276 ◽  
pp. 236-241
Author(s):  
Iveta Hájková ◽  
Petr Novosad

Sulfur binders belong to the group of airbrushes. They can therefore only harden and harden in the air. The main raw material, gypsum, can be mined in several places in the world. Even in the Czech Republic there is a deposit of natural gypsum in Kobeřice u Opavy. [5] In spite of this fact, we use mostly industrially produced gypsies, because the natural gypsum deposit has only very limited capacity. The Energogypsum, produced in the Czech Republic by ČEZ Energetické Produkty s.r.o., is the waste product of flue gas desulphurization using the wet limestone scrubbing method. Like the chemosynthesis, it is characterized by its high purity (the content of pure CaSO4 2 H2O is at least 90%). The one in the Czech Republic is manufactured by Precheza, a.s. in Přerov. The use of sulphate binders is varied. A better form in the form of alpha plaster is used to produce self-leveling floors and dentistry. Less-quality beta gypsum has a larger application. From it we can produce both gypsum and monolithic partitions. We can also use it for the production of plasterboard and gypsum fiber boards and, last but not least, as internal plasters for its good fire performance. [1] Plasters are being prepared today in two different ways. Firstly, they are still prepared in the original outpatient way directly on the building from individual raw materials, but they are also industrially produced in the form of dry mortar mixtures, which are mixed on the building only with water. The second way is more progressive with the fact that nowadays it is even more widespread. For many builders, however, it remains financially scarce. That is why we have recently begun to find a compromise solution that will satisfy both the technical and the economic ones. This is the development of the so-called binder premixes, ie the industrially produced mixed binder, which is mixed only with sand and water on the site. The situation on our market shows that the recently developed special premix for lime-cement plaster and mortar mixtures is very positive for the building public and therefore the effort is to generalize this mixed mortar in the production raw material base and, in addition, to develop its analogue based on sulphate binder. [2]

Author(s):  
K. Shevchenko ◽  
A. Grigorov ◽  
I. Sinkevich

In order to improve the performance properties, in particular viscosity-temperature, of boiler fuel, it is proposed to combine them with narrow fuel fractions obtained by thermal destruction of secondary polymer raw materials (low pressure polyethylene and polypropylene). When compounding grade 100 fuel oil with narrow fuel fractions, the values ​​of density are reduced to 865 (873) kg / m3, conditional viscosity to 2.50 (2.63) deg. um., pour point up to 8 (13) °C), sulfur content up to 0.17 wt%. and the lower heat of combustion increases to 43606 (43850) kJ / kg. At the same time, there is a gradual decrease in the value of the flash point to 114 (127) °C. This reduction is a negative point, which leads to increased fire safety of fuel oil during its use, storage, pumping and transport. However, the values of the flash point, according to the requirements of regulatory documentation, are within acceptable limits. That is, the value of this indicator can limit the content of fuel oil in narrow fuel fractions. It is determined that the rational concentration of narrow fuel fractions in the composition of fuel oil grade 100, is within 30% of the mass. Within these limits, there is a permissible decrease in flash point values – an indicator that characterizes the fire hazard of fuel oil during its use, storage, pumping and transportation against the background of improving other performance properties of fuel oil. The production of the proposed compound boiler fuel on the one hand allows to expand the raw material base of the process by involving in the production process secondary polymer raw materials – solid waste subject to mandatory disposal, on the other – to meet existing demand for boiler fuel by increasing its production.


2018 ◽  
Vol 9 (3) ◽  
pp. 23-27 ◽  
Author(s):  
Beáta Korandová ◽  
Alena Straková ◽  
Jiří Beránek ◽  
Dana Vrublová

This article summarizes the information on raw materials in the Czech Republic. Although mining was significantly reduced not long ago, there are still rich deposits of ores, non-metallic raw materials, as well as energetic and construction ones. Many of them are potentially utilizable in future, especially those which are economically favorable, and their mining is not in any conflict with environmental interests. Deposits are distributed irregularly, and their raw materials are different in both the Bohemian Massif and Western Carpathians. In order to be complete, the text also comprises deposits, which are restricted by environmental limits or their mining promises a low-cost effectiveness. The article is amended with actual statistical data.


Energies ◽  
2021 ◽  
Vol 15 (1) ◽  
pp. 47
Author(s):  
Dalibor Šafařík ◽  
Petra Hlaváčková ◽  
Jakub Michal

In the European Green Deal and the Climate Act, the European Union has committed itself to achieving climate neutrality by 2050. This goal is to be achieved by joint efforts of all economic sectors, including forestry and its downstream sectors. One way to attain this goal is the effective and sustainable use of forest biomass for energy production. This article aims to quantify the potential of forest biomass resources for the production of electrical and thermal energy based on official departmental statistics, the current legal framework for forestry and the environment, and research results in the context of an extreme change in the raw material base due to the ongoing calamity caused by the spread of insect pests in the Czech Republic. This extreme can classify as a significant risk to the security of the energy supply from renewable sources in the event of oversizing new installed energy production from renewable sources. Based on data and calculations, an overall annual volume of dendromass available for energy production in the Czech Republic for the period extending to 2036 was quantified at the value of 13.473 million tons per year. Consequently, it is clear that the overall dendromass resources for energy production in the Czech Republic are not sufficient to achieve the EU’s ambitious objective.


Author(s):  
I. F. Iskakov ◽  
G. A. Kunitsyn ◽  
D. V. Lazarev ◽  
А. А. Red`kin ◽  
S. A. Trubitsyn ◽  
...  

To use effectively internal raw material base, JSC “Ural Steel” accomplished I category major overhaul of the blast furnace No. 2. The main purpose of the overhaul was to design a rational profile which could ensure an ability to operate with a charge containing 95 % of Mikhailovskii GOK (mining and concentrating plant) pellets having basicity of 0.5 by CaO/SiO2. The blast furnace No. 2 having useful volume of 1232 m3, was constructed by design of Danieli Corus, the Netherlands, and was blown in on December 30, 2020. In the process of guarantee tests, step-by-step increase of Mikhailovskii GOK pellets (Fetotal = 60.5 %, CaO/SiO2 = 0.5) content in the charge iron ore part was being accomplished from 55 to 95.1%. Charging of the blend containing pellets in the amount of 55% of iron ore part, was done by charging system 4OOCC + 1COOCC (Ore - Coke) with filling level 1.5 m. Under conditions of pellets part increase in the blend, the charging system was changed to decrease their content at the periphery, to increase it in the ore ridge zone and make it intermediate between periphery and the ore ridge. At the pellets share in the iron ore raw materials 0.75 the charging system was used as the following: 3OOCC + 1COOC + 1COOCC, while at the content 95.1% the following charging system was used: 2COOC + 2COOC + 1COOCC. It was noted that in the period of guarantee tests the furnace running was smooth. The average silicon content in the hot metal was 0.70% at the standard deviation 0.666. Sulfur content in the hot metal did not exceed 0.024%, the blowing and natural gas consumption figures were 2100 m3/min and 11000 m3/min correspondently, oxygen content in the blowing 26.5%, hot blowing and top smoke pressure figures were 226.5 and 109.8 KPa correspondently. The productivity of the furnace was reached as high as 2358 t/day at the specific coke rate 433 kg/t of hot metal. After guarantee tests completion, the pellets content in the iron ore part was decreased gradually from 95 down to 50%. The decreasing was made by 5% in every 6 hours of operation. Application of the mastered technology of the blast furnace No. 2 with the increased share of pellets will enable to stably supply the blast furnaces No. 1, 3 and 4 by iron ore raw materials in the proportion of 30-35% of pellets and 65-70% of sinter.


2021 ◽  
Vol 316 ◽  
pp. 1050-1054
Author(s):  
V.N. Zyryanova ◽  
E.V. Lytkina ◽  
A.P. Ochur-Ool

Increasing water resistance and mechanical strength of hardening magnesian binders’ products can be achieved by introducing microfillings into a hardening dispersed system. It is shown that serpentine provides an increase strength and water resistance in hydration and hardening process, being as a structure-forming component, it intensifies this process. It allows expanding the raw material base for the production of magnesia binders for construction purposes.


2021 ◽  
Vol 9 (16) ◽  
pp. 90-97
Author(s):  
Kateryna Danilova ◽  
◽  
Oksana Zavarzina ◽  

An actual problem of the alcohol industry development is the expansion of the raw material base through the use of new, cheaper types of carbohydrate sources. Recently, glucose-fructose syrup has been of increasing interest to producers of ethanol. Among the producers of craft drinks, in particular rum-based drinks, cane molasses is in increasing demand. The article presents the technological aspects of the fermentation process of nonconventional sugar-containing raw materials on the example of glucose-fructose syrup and cane molasses in ethanol by different yeast strains. It is determined that glucose-fructose syrup and cane molasses are raw materials depleted of nitrogen, phosphorus and growth substances necessary for the yeast activity. To improve the technological properties of raw materials in the molasses, nitrogen, phosphorus nutrition and corn extract as a growth substance shall be added to a mash. Glucose-fructose syrup is of pH 3.68 and of acidity 0.12, which negatively affects the fermentation. It is established that in order to create optimal living conditions for yeast, it is necessary to add substances to the glucose-fructose syrup that will contribute to the safety of development and prevent the pH 3.5. It was determined that the alcohol yield from 1 ton of glucose-fructose syrup is 31.0 dal, from 1 ton of cane molasses is 24.0 dal on the yeast 46ED and 22 dal on the TegaYeast without the use of growth substances and vitamins necessary for the reproduction of yeast biomass. Under conditions of improving the technological properties of the mash from the glucose-fructose syrup and cane molasses by adding biologically active substances promoting the synthesis of yeast biomass, the ethanol content in the fermented mashes increases up to 11.9 12% vol.


2021 ◽  
Vol 9 (A) ◽  
pp. 313-317
Author(s):  
Svetlana Ivasenko ◽  
Ainur Zhumabekova ◽  
Agnieszka Ludwiczuk ◽  
Krystyna Skalicka–Wozniak ◽  
Alexandr Marchenko ◽  
...  

BACKGROUND: A possible reduction in stocks of medicinal plant raw materials of Thymus serpyllum L. and Thymus vulgaris L. leads to the need to expand the raw material base of the official medicinal plants with using of endemic species of the flora of Kazakhstan, in particular, Thymus rasitatus Klokov, and Thymus eremita Klokov. AIM: The aim of the study was to study the possibility of using 70% ethanol extracts of T. rasitatus and T. eremita as antimicrobial agents. MATERIALS AND METHODS: The aerial parts of T. rasitatus and T. eremita were extracted with 70% ethanol using ultrasound assisted extraction. The qualitative and quantitative analyses of the 70% ethanol extracts were determined using the liquid chromatography-detection-ESI-mass spectrometry-(MS)/MS technique. The study of the antimicrobial activity of these extracts was performed for eight strains of Gram-positive bacteria, six strains of Gram-negative bacteria, and four cultures of fungi. RESULTS: Chromatographic analysis of hydroalcoholic extracts of both investigated Thymus species showed very similar phenolic compounds composition. In both cases, the major components are luteolin-7-O-glucoside and rosmarinic acid. About 70% ethanol extracts of T. rasitatus and T. eremita have a broad spectrum of antimicrobial activity, exhibit the bactericidal or bacteriostatic activity against all tested bacteria and fungi at concentration range of 0.0195–20 mg/ml, but differ in their potency against tested strains of microorganisms. CONCLUSION: About 70% ethanol extracts of T. rasitatus and T. eremita, endemic plants in the flora of Kazakhstan, can be considered as potential drugs with a wide spectrum of antimicrobial activity. The results of chromatographic analysis could be used for drug standardization.


2020 ◽  
Author(s):  
P.A. Kozlov ◽  
A.M. Panshin ◽  
L.I. Leontiev

The increasing demand for zinc and a range of zinc-related metals (for example: lead; indium; tin; cadmium; and copper) in the Russian Federation cannot be satisfied by the existing production plants due to the lack of raw materials. At the same time, ferrous and non-ferrous metallurgy and the chemical industry have accumulated hundreds of millions of tons of zinc wastes (falling into the hazard categories 2 to 4), the processing of which could not only make up the raw material base, but also improve the environmental situation. In the world, over 85% of ferrous dust is recycled using the Waelz process. The Waeltz process is used for distilling separation of elements under reducing conditions. In this study, a block diagram for production of the following elements from industrial wastes is proposed: zinc, cadmium and indium in form of massive metals; zinc and indium in the form of fine powders; and clinker as a raw material for cement production. The technical and scientific details of this new process have been patented in the Russian Federation and abroad. For the first time, the following operations have been implemented with the use of large-sized Waelz kilns: vapour-oxidized Waeltz treatment of polymetallic wastes; recycling of heat from gases and solid products with generation of process fumes; and implementation of alternative flux (dolomite) and alternative fuel (petroleum coke). Keywords: Waelz process, industrial wastes, heat recycling, vapour-oxidized Waelz processing


2015 ◽  
Vol 1 (12) ◽  
Author(s):  
Slobodan Majstorović ◽  
Vladimir Malbašić ◽  
Miodrag Čelebić

Curent situation of raw material base and study of limestone like construction stone deposits in the Republic of Serbian were relatively poorly considered during the last decades, and the main problems are the following: low production capacity fragmentation of production, needs for raw materials homogenization and delivering of standard quality, undeveloped market, the recession of the domestic economy and the economies in the region, the relatively low level of exploration by many deposits, especially lack of knowledge of the occurrence legality for certain types and quality of raw materials and lack of complete quality indicators for raw material, which sometimes causes the utilization of only the highest quality deposit parts.This paper provides an overview of active quarries in the Republic Srpska with exploitation of limestone like technical building stone and present an attempt to determine the basic quantitative and qualitative characteristics of the raw material and the current working conditions at these quarries. The purpose of such a review would be in an effort to create a clearer picture about production, market, social and other aspects of the limestone exploitation in the Republika Srpska and the realistic possibilities of maintaining and developing of these mineral resources utilization, which can certainlybe interesting for the development of many other industries in the Republic Srpska.


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