52 research outputs found
Fabrication of slag-glass composite with controlled porosity
The preparation and performance of porous ceramics made from waste materials were investigated. Slag from thermal electrical plant Kakanj (Bosnia and Herzegovina) with defined granulations: (0.500÷0.250 mm); (0.250÷0.125 mm); (0.125÷0.063 mm); (0.063÷0.045 mm) and 20/10 wt.% of the waste TV screen glass with a granulation <0.063 mm were used for obtaining slag-glass composites with controlled porosity. The one produced from the slag powder fraction (0.125÷0.063 mm) and 20 wt.% TV screen glass, sintered at 950°C/2h, was considered as the optimal. This system possesses open porosity of 26.8±1.0%, and interconnected pores with the size of 250–400 μm. The values of E-modulus and bending strength of this composite were 10.6±0.6 GPa and 45.7±0.7 MPa, respectively. The coefficient of thermal expansion was 8.47·10-6/°C. The mass loss in 0.1M HCl solution after 30 days was 1.2 wt.%. The permeability and the form coefficient of the porous composite were K0=0.12 Da and C0=4.53·105 m-1, respectively. The porous composite shows great potential to be used as filters, diffusers for water aeration, dust collectors, acoustic absorbers, etc
Glass Ceramics Composites Fabricated from Coal Fly Ash and Waste Glass
Great quantities of coal ash are produced in thermal power plants which present a double problem to the society: economical and environmental. This waste is a result of burning of coal at temperatures between 1100-14500C. Fly ash available as fine powder presents a source of important oxides SiO2, Al2O3, Fe2O3, MgO, Na2O, but also consist of small amount of ecologically hazardous oxides such as Cr2O3, NiO, MnO. The combination of the fly ash with waste glass under controlled sintering procedure gave bulk glass-ceramics composite material. The principle of this procedure is presented as a multi barrier concept (1). Many researches have been conducted the investigations for utilization of fly ash as starting material for various glass–ceramics production (2-4). Using waste glass ecologically hazardous components are fixed at the molecular level in the silicate phase and the fabricated new glass-ceramic composites possess significantly higher mechanical properties.
The aim of this investigation was to fabricate dense glass ceramic composites using fly ash and waste glass with the potential for its utilization as building material
Materials Engineering
The material presented in this book is the last part from the five books series
which are resulte of the aforementioned project.
Sustainable development, pariculary for industry was the base for developing
of these educative materials. Part of the contents presented in the previous
books covered the temas which generally are connected with sustainable
development, but this book coveres the types of materials in general and
the management of the waste materials. The nowdays fast development
which results in intensive way of leaving is as a consequence of the development
of different kinds of materials which can be finde in various segments
of everyday life. So, in the first part of this book in particular thematical parts
are presented the different kinds of materials like: polymer materials, metals
and alloys, ceramics materials, glass, composite materials and eco-composite
materials. Also, as content in this part of the book are the themas: science
and engineering of materials, nanotechnology and nanomaterials and modern
electrode materials in the hydrogen economy. In the first part of the book
the particular attention is given on ther type and usage of materials starting
from the operable moto in the science and engeneering of materials i.e. the
thetrade: synthesis – structure – properties – application.
The second part of this book thematically covered the treatment of waste
in the materials engineering in general, but also the actual themas from the
management of waste are presented like recycling of: polymers, metal sctap,
glass and refractories. The production of ceramics from waste and end of life
treatment of polymer composite materials present the two parts consisted in
the second part of the book.
In this part of the book the particular attention was payed on the diferent
types of materials which can be treated as raw materials from which new or
the same products can be produced. Also,the attention was payed on the
treatment of waste as energy resourse
Value added utilization of by-product electric furnace ferronickel slag as construction materials: A review
This paper reviews the potential use of electric furnace ferronickel slag (FNS) as a fine aggregate and binder in Portland cement and geopolymer concretes. It has been reported that the use of FNS as a fine aggregate can improve the strength and durability properties of concrete. Use of some FNS aggregates containing reactive silica may potentially cause alkali-silica reaction (ASR) in Portland cement concrete. However, the inclusion of supplementary cementitious materials (SCM) such as fly ash and blast furnace slag as partial cement replacement can effectively mitigate the ASR expansion. When finely ground FNS is used with cement, it shows pozzolanic reaction, which is similar to that of other common SCMs such as fly ash. Furthermore, 20% FNS powder blended geopolymer showed greater strength and durability properties as compared to 100% fly ash based geopolymers. The utilization of raw FNS in pavement construction is reported as a useful alternative to natural aggregate. Therefore, the use of by-product FNS in the construction industry will be a valuable step to help conservation of natural resources and add sustainability to infrastructures development. This paper presents a comprehensive review of the available results on the effects of FNS in concrete as aggregate and binder, and provides some recommendations for future research in this field
Creation of university-enterprise cooperation networks for education on sustainable technologies
The aim is to improve the university-enterprise cooperation in the process of
creating sustainable industry in Serbia, Bosnia and Hercegovina and Macedonia and to promote
the sustainable concept of zero emission which aim is maximum resource productivity and virtually
no waste. The goal was realized by creating the lifelong learning course (LLL ) for the needs of
the industry consisting of general part (sustainable technologies) and specific parts depending
on the particularity of the participant industry in the project, i.e. food industry, pharmaceutical and
cosmetic industry, chemical engineering and materials engineering. The course was covered with
the written material given in five books with the following titles: sustainable technologies, sustainable
technologies in food industry, sustainable technologies and chemical engineering, sustainable
technologies in pharmaceutical and cosmetics industry and materials engineering. Also, the modern
computer laboratory was opened at the faculties which implemented the project. The course was
realized by each university (three months, 150 hours, 6 ECTS ) and more than 200 participants from
the industry of the Balkan countries successfully finished the LLL course
Sustainable technology and natural environment
Sustainable technology is usually connected with the design and analysis of complex, integrated management systems and sustainable development and it is a central target in environmental science and growth of global economies. The minimization of waste and reductions in material and energy inputs are the most important environmental aims. Sustainable technological development and innovations do not automatically lead to total reduction of environmental burden of industrial production. However, technological innovation is an important factor and seems to play a central role in the long-term initiation of cleaner production. Environmental improvement of companies strategy by application the idea of cleaner production linked with sustainable technologies leads to produce environmentally friendly products and leads to increas the position of company on the market.
Key words: sustainable technology; sustainable development, environmental effects
Composites based on fly ash and clay
Fly ash is a waste generated from the coal combustion during the production of electricity in the thermal power plants. It presents industrial by-product containing Technologically Enhanced Natural Occurring Radioactive Materials (TENORM) with the great potential for valorisation (1). Fly ash is successfully utilized in cement and concrete industry (2), also in ceramics industry (3) as component for manufacturing bricks and tiles, and recently there are many investigations for production of glass-ceramics (4) from fly ash. Although the utilization of fly ash in construction and civil engineering is dominant, the development of new alternative application for its further exploitation into new products is needed. This work presents the possibility for fly ash utilization for fabricating dense composites based on clay and fly ash with the potential to be used in construction industry
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