Historical overview of refractory lining in the blast furnace

The majority of refractories used today are associated with the iron and steel industries. Typically, the refractory lining of a blast furnace consists of a combination of different refractory materials chosen for different portions of the furnace, as well as distinct process conditions and temperature ranges. Knowledge and requirements for the iron manufacturing system in conjunction with the physical, mechanical, and chemical qualities of the proposed refractories determine the choice of refractory combination. Inadequate understanding of the aforementioned components frequently results in refractory failure, which then becomes a difficult problem to tackle. A blast furnace's refractory liner typically fails owing to any number or combination of these variables. To facilitate comprehension, we will explain the types of refractory lining required in a blast furnace by region, as well as the observed trend in refractory lining patterns over the past few decades

Preparation and properties of low cement castable sintered at different temperatures

The low cement high alumina castable (LCC) studied in this paper was synthesised, cured and then treated at different sintering temperatures. Since any inhomogeneity introduced during the castable preparation can remain inside the material degrading its properties and therefore the quality during service life, particular attention was given to the processing procedure in order to produce the material with the optimum characteristics. Composition of the castable regarding particle size distribution was adjusted according to the Andreassen’s packing model. The samples were sintered at 1100, 1300 and 1600°C for three hours. Influence of the different sintering temperatures on the castable properties is discussed. Compressive and flexural strengths were determined by destructive testing method, while the water immersion method was used for determination of the bulk density and the water absorption. Changes of elastic properties and microstructure (porosity) were observed by the non-destructive testing methods, ultrasonic measurements and image analysis. Based on the results, it can be concluded that sintering temperature has strong influence on the properties of the LCC. Exceptionally good properties were obtained for the sample sintered at 1600°C, but it should be highlighted that the samples treated at 1100 and 1300°C were provided with good properties, too. This should not be neglected because of the energy saving importance, in cases where the material sintered at lower temperature satisfies the application requirements

Senzor na bazi mezoporozne silike za kolorimetrijsko određivanje boje Basic Yellow 28 u vodenim rastvorima

The textile industry is one of the largest water-consuming industries in the world. The wastewater generated by the textile industry is a major source of pollution, containing mostly dyes, but also detergents, and heavy metals. Since dyes can have a negative impact on the environment, human and aquatic life, it is really important to find proper solutions for removal of these pollutants from wastewater. In addition, special attention is given to the discovery of new and fast "in situ" methods for identification and quantification of pollutants from wastewater. In this paper, SBA-15, mesoporous silica material, was used as sorbent for removal of Basic Yellow 28 from aqueous solutions. In addition, colored SBA-15 after sorption process was subjected to image analysis, to evaluate if it was possible to quantify sorbed dye on sorbent based on intensity of SBA-15 coloration. The obtained results revealed that SBA-15 could remove 99% of dye within 5 min. The highest efficiency of dye removal was at pH8, using 200 mg of sorbent. According to the Langmuir isotherm model, the theoretical maximum sorption capacity was 909 mg/g. Image-Pro software confirmed that it would be possible to quantify sorbed dye onto SBA-15 with accuracy of 0.98. Overall, SBA-15 demonstrated to be efficient sorbent in removal of Basic Yellow 28 from water, but also to be potential carrier as a sensor for detection of colored pollutants in water.Tekstilna industrija je jedna od najvećih potrošača vode u odnosu na druge industrijske grane. Otpadne vode iz tekstilne industrije su jedan od glavnih izvora zagađenja i uglavnom sadrže boje, ali takođe i deterdžente i teške metale. Pošto boje mogu imati negativan uticaj na životnu sredinu, ljude i vodeni svet, važno je pronaći odgovarajuća rešenja za uklanjanje ovih zagađivača iz otpadnih voda. Pored toga, posebna pažnja je posvećena otkrivanju novih i brzih „in situ” metoda za identifikaciju i kvantifikaciju zagađivača iz otpadnih voda. U ovom radu kao sorbent za uklanjanje Basic Yellow 28 boje iz vodenih rastvora korišćen je SBA-15, mezoporozni silika materijal. Pored toga, obojeni SBA-15 nakon procesa sorpcije podvrgnuti su analizi slike, kako bi se procenilo da li je moguće kvantifikovati sorbovanu boju na sorbentu na osnovu intenziteta obojenosti SBA-15. Dobijeni rezultati su pokazali da SBA-15 može ukloniti 99% boje u roku od 5 minuta. Najveća efikasnost uklanjanja boje bila je pri pH 8, korišćenjem 200 mg sorbenta. Prema Langmuirovom modelu, teoretski maksimalni kapacitet sorpcije bio je 909 mg/g. Softver Image-Pro je potvrdio da je moguće kvantifikovati boju na SBA-15 sa tačnošću od 0,98. SBA-15 se pokazao kao efikasan sorbent u uklanjanju Basic Yellow 28 boje iz vode, ali i kao potencijalni senzor za detekciju obojenih zagađivača u vodi

Shape memory alloys: Properties, demands and opportunities in engineering applications

Shape memory alloys (SMAs) are a subclass of shape memory materials (SMMs), which are materials that, in response to a specific impact like thermal, mechanical, or magnetic changes, can "memorize" or hold into their prior form. This review addresses the properties, demands, and application prospects of SMAs, and provides a synopsis of recent advancements, as well as a historical background. Due to their special and exceptional qualities, SMAs have attracted a lot of interest and attention recently in a wide range of commercial applications; basic and applied research investigations have supported this commercial development. In order to shed light on design, issues faced by SMA developers, this paper explains the characteristics of these materials that make them perfectly suited for variety of applications, addressing also the accompanying constraints. This paper offers a pertinent overview of current SMA research

Non-destructive evaluation of sulfur-polymer composite behavior under induced destruction influence

In order to avoid undesirable effects, caused by interactions between the material and environment, changes in properties of materials during their exploitation periods have to be determined. In this research, the induced destruction methodology was applied for evaluation of material behavior. The methodology is based on the usage of agents in increased concentrations that can lead to destruction of the material (cause changes in physical, chemical and mechanical properties) as fast as possible. Sulfur-polymer composite was exposed to the influence of hydrochloric acid, which was chosen as an induced destruction agent. The analysis of sulfur-polymer composite behavior required methods capable of quantifying the material microstructural characteristics. Since sulfur-polymer composite is inhomogeneous material, evaluation of its properties, as well as the effect of external influence on its microstructure, was investigated using non-destructive methodologies. Image analysis and ultrasonic measurements were applied to quantify the material destruction on the surface and in the bulk. Morphological and structural changes in the inner structure of sulfur-polymer composite were inspected by scanning electron microscopy (SEM). According to the obtained results, used methodologies present a powerful tool for the characterization of phenomena occurring in the specimens during the investigation

Possibility of using diatomaceous earth from Kolubara and Vesje deposits for production of beer filter aids

Diatomaceous earth is a non-metallic mineral raw material composed of skeletal remains of single-cell water plants, known as diatomite. Owing to quite complex structure of skeletal diatomite with numerous fine microscopic pores, cavities and channels and, therefore, large specific surface area and high adsorption capacity, diatomaceous earth can be used as adsorption auxiliary material for filtration. It is suitable for production of filtering compounds used in breweries. Two of several deposits on the Balkan Peninsula, the Kolubara deposit in Serbia and Montenegro, located 60 km south of Belgrade and the Vesje deposit in the Former Yugoslav Republic of Macedonia located near Negotino, were selected for the purpose of investigating their possible application in preparation of beer filter aids. With the aim of predicting the filtration efficiency, chemical, mineralogical and structural properties of diatomite samples were analyzed and parameters of crushing, drying, calcination and classification were defined. The results showed that there are certain differences in processing technology of two investigated deposits but both types of diatomaceous earth can be used for the production of beer filter aids. Beer filtration tests proved diatomites to be satisfactory and not causing any degradation of filtration process or beer quality. Technological flow scheme for obtaining the beer filter aids is proposed in this research

Traditional Ceramics: Past, Present and Future

In this paper review of the traditional ceramics will be given. Different types of ceramics will be discussed, in correlation with historical time and use, as well the present time and future perspecives of tradiotional ceramics. Processing of the tradiotional ceramics, as well as diffrences in procesing during time will be also discussed. Past of the traditionnal ceramic will be focused on pottery, glass and construction and optic materials. Present time will include traditional engineering ceramic. Traditional ceramics in future will be related to the possible application and synthesis of modern ceramic materials

Blast furnace refractories: Past, present, future

Most of the refractories used today are related to iron and steel industry. Grate part of the refractory lining related to blast furnace are combination of different refractory materials selected for different parts of furnace, as well as different process conditions and temperature range. Selection of appropriate refractory combination depends on knowledge and demands for iron making system in combination with the physical, mechanical and chemical properties of the proposed refractories. An improper understanding of the above factors often leads to a refractory failure which, subsequently, becomes a complex problem to solve. Refractory linings whether it is of a blast furnace or any other furnace, usually fail due to any number or combination of such factors. For the convenience of understanding, here we will discuss the types of refractory lining required in a blast furnace area as well as the trend in the refractory lining pattern that has been used during the last decades

Leaching behavior of sulfur concrete with fly ash used for removal of heavy metals from wastewater

When considering the materials that have become waste in a technological process, one way of their immobilization is for the production of certain new materials. The basic fact is to provide the environmentally acceptable level of the produced material. In this research fly ash from ’’Power Plant Nikola Tesla’’ Obrenovac was used as an sorbent for removal of heavy metals from flotation wastewater originating from artificial lake ’’Cerovo’’. After the sorption, fly ash was used as filler for the production of sulfur concrete. Sulfur concrete samples with standard dimensions were subjected to leaching tests by immersion in distilled water during the period of up to six months. Leaching is the process by which different contaminants are released from the solid phase into the water phase. The process itself is universal, as any material exposed to contact with water will leach components from its surface or its interior depending on the porosity of the material considered. Results of examining leaching degree of heavy metals from the sulfur concrete samples with fly ash as filler showed that the leaching degree of all metals (copper, cadmium, zinc, iron, nickel) except manganese was negligible. It can be concluded that in the sulfur concrete samples with fly ash as filler, immobilization of heavy metals occurred