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Plastics are materials used in almost all areas of human activity and also in various branches of industry and in life in general. The growing production of plastics, their volume are evenly growing up also in the waste, therefore it is necessary to solve the plastic waste problem. The contribution deals with the using of recycled plastics plates and testing of sorted plastic waste. From the plastic waste as the semi-products re prepared for example the plastic plates by extruding technology, it means recycled pla...

The article presents the results of investigations into the chemical composition, contents of selected rare earth elements and the reaction of eluates obtained from the waste (ash and slag) produced in the process of hard coal combustion in a pulverized-fuel boiler. Samples for tests were taken from the ash and slag landfill from three 10-metre vertical profiles. The total content of REEs in the examined ash-slags ranges from 295 to 366 mg/kg. The average concentration of rare earth elements is 330 mg/kg, with a s...

End-of-life solar photovoltaic (PV) panels represent a waste stream that will show high and rapid increase from 2020 onwards. Annual quantities could rise by a factor of 25 or higher in the period 2020 to 2050, turning waste PV panels into a material stream that will account for a significant share of waste electrical and electronic equipment occurrence. Assessing the types of modules on the market displays a high and further growing variety of PV panels, showing differences in design, basic technology and used co...

As direct consequence of the urban development, waste management is a multidimensional issue that incorporates political, institutional, social, environmental, and economic aspects. The paper aims to analize the efficiency of waste management strategy, implemented in the town of Boto?ani. It is also considering, the populationпїЅs level of education and perception, regarding selective collection and the quality of public Sanitation Services. Boto?ani is a second rank town (the most important in Boto?ani county), l...

Further to the global trend of using wastes as secondary resources, also in the Czech and Slovak Republic there is an emphasis on the new benefication of wastes in terms of their further utilization and recycling in technological processes. The utilization of wastes does not only broaden the raw material base, but it also helps to save the primary sources of minerals as well as there are lower costs of waste transport, dumping and disposal thanks to their complex utilization. The paper deals with the application o...

The paper deals with the issue of separating biodegradable PLA (polylactic acid) bottles from conventionally used packaging materials such as PET (polyethylene terephthalate). The separation of these materials is especially important because each of the plastics has a different cycle at the end of its secondary use. Recycling PET bottles the quality of the granulate may be degraded due to the occurrence of PLA material, while the occurrence of PET is undesirable during composting the biodegradable plastics PLA as ...

Waste management is pressing harder with the alarming signal warning the industry. The success of local recycling programmes is reliant upon households’ participation. Recycling of solid wastes is considered as the only method to recover the waste generated. In recognition of this, doorstepping approach is used as one the main driver tools towards increasing households partic ipation. This study was based on selected residential areas (different level incomes) within Kuala Terengganu town (Malaysia). Questionnai...

Recovery of gold and other valuable metals from electronic scrap involves a complex metallurgical flow sheet and requires state- of-the-art recovery technologies that are available in large-scal e, integrated smelter-refinery opera tions. At the end of their use, electronic and other el ectrical product scrap offer an important recycling potential for the secondary supply of gold and silver into the market. With gold concentrations reaching 200-250 g/t for computer circuit boards, this scrap is an ‘urban mine’...

The paper presents the main factories which determine the environment pollution at hot dip galvanization process of steel sheet and developing of recycling technologies of zinc by-product, with a view to recovering metal zinc or different sub- products, and returning them in the production cycle. By th e recycling of zinc by- products the prime material consumption is reduced and enviro nmental protection is improved. Industrial wastes generated in the hot dip galvanization pr ocess of steel sheet are: zinc ash, d...

In the world, over 18 million vehicles are rejected annually from operation. The spent catalysts are obtained from th e vehicles at the end of their life cycle as well as the vehicles which do not meet the prescribed st andards in the ECO test respected to the composition of exhaust gases. The basis of each catalyst is a ceramic monolith with deposited valuable platinum metals. The spent catalysts are solid waste and also the rich raw material for recovery of precious metals. The aim of this paper is a separation ...

Zinc is a widely applicable metal and therefore the different composition and form of zinc waste is generated. The most important waste material generated in production and processing of zinc is scrap metal of zinc and its alloys, as well as slag, dust and sludge from the production and processing of cat hode zinc and zinc alloys. In terms of processing technology, there are different app lied procedures depending on the type of raw material. The processing of waste zinc a nd its alloys is pyrome tallurgical and i...

The power plants produces hundreds tones of fly ashes yearly. From this amount is really used in the reason only 10 % with out the any treatment in the industrial production. The rest of this ashes are de posited on dumps and settling pits, that have many negative influence on the environment. Following the previous results from the extensive treatment research was proposed the waste less technology of the complex treatment and utilization of black coal fly ash. The final products of this technology are the produc...

It is proposed to process gold mine man-made wastes through ultrasonic activation of source materials in water, then in an alkaline solution with subsequent cyanidation of gold-impregnated cakes, or direct cyan idation and sorption conditioning of gold multicomponent solutions with nano-structured anionite an av erage radius of pores of which is within 600-700 Зє that contains no more than 6-8% of strong-base groups. A preliminary withdrawal of elements accompanying gold ensures obtaining of good- quality target m...

Geotextiles are used commonly in domestic solid waste disposal sites as a protector filter and separator. Because, sand and silt particles included in waste leachate can fill space of gravels which are using as drainage layers. Therefore, the space of the drainage layer is bunged up with particles and it is decompose. This case is not wanted so the usage of the geotextiles has quite importance in waste disposal sites. In general, geotextile lies between waste and drainage layers and it is used to filtration. In or...

Significant efforts should be devoted to reducing waste outputs from aquaculture operations in order to lower the environmental impacts of aquaculture in many parts of the world. Since most aquaculture wastes are ultimately from dietary origin, reduction of waste outputs should first be through improvements of diet formulation and feeding strategies. The first step in the production of feeds producing less solid waste is to eliminate poorly digestible ingredients (such as whole grain or grain byproducts used as bi...

The increasing amount of poly(ethylene terephthalate) (PET) waste is a worldwide problem which has induced requirements for its recycling and reusing. PET fibres have been used as a dispersed micro-reinforcement in a cementitious matrix. The microreinforcement in the fibre reinforced concrete absorbs tensile strain and prevents formation of microcracks originating from concrete shrinkage. The present work has been aimed at studying the effects of aging PET fibres by alkali hydrolysis and temperature cycles on the ...

An important element in the process of construction and demolition waste (CDW) recovery is the costs, which is necessary to incur in the recycling. The transportation costs create a significant part in total costs of recycling company. This is the main reason, why is important to deal with the distribution system of waste recycling, as well. We are able to define the model of CDW recycling following the analysis of recycling systems, its elements, mutual interactions and the ways of its existing in the real condit...

In this study our object is management of obsolete pharmaceutical products, vaccines and other medical waste as: syringes, needles and vials after vaccination. A right way of waste management in generally is very important for one health environment and health life. It is responsibility of everyone to take care of environment. Our focus must be on reducing the hazardous nature and the volume of our waste, and separate more of their waste, and increasing our participation in work on waste management according EU le...

Waste deposing is the most important problems for a sustainable development of our societies. In this paper is shown some models, for determinate the exploitation with optimum fees of the waste deposing on the landfill. The model take in account local condition of warehousing, the existing of sorting technology, technical and managerial abilities in waste management, the support for an efficient strategy in regard to tariffs, billing and bills collections. The overall objective is to develop the necessary infrastr...

In process of pig iron production besides main product, pig iron, also secondary products are formed, that have character of secondary raw materials and industrial wastes. The most abundant secondary product originating in the process of pig iron production, is blast furnace slag, its occurrence is about 300 to 500 kg for one ton of pig iron. Blast furnace slag originates from melting of gangue parts of metal bearing materials, slag forming additions and coke ash. Its chemical, mineralogical and physical – chemi...

The aim of this work is the optimization of sinter-crystallization regime of a glassceramic from a municipal solid waste incineratior (MSWI) bottom ash. The parent waste was melted at 1400oC, milled below 75 $\mu$m and the obtained glass powders were pressed at 100 MPa. The optimal temperature for sinter-crystallization was estimated by DTA, dilatometry and XRD. Subsequently, the degrees of sintering, obtained at different heating rates (between 2 and 40oC/min) and 1 h step at 950oC were estimated by the linear sh...

A detailed investigation of physical and chemical properties of pyrite cinders from sulfuric acid production has been carried out by employing variety of analytical methods and techniques, including ICP-MS, XRL, XRD, M\"ossbauer Spectroscopy, SEM-EDX, SQUID, TGA, etc. The study is focused on the investigation of the content and distribution of about 50 micro- and trace elements in magnetically separated fractions, and among/within individual particles. It has been found that many heavy metals exist in easily avail...

Perspective conception is characterized by including of wastes assembly problems in sphere of general actions for environment protection taking into account as any nonvalorized waste or least non-used, pollute the environment. Processing of solid minerals sterile and obtaining of sub-products which are economically usable has major importance, both from economical and ecological point of view, through environment protection. Researches had followed elaboration of ecological technologies of processing the waste as ...

Returnable and non-returnable losses rise during melting and casting of molten metal. Non – returnable losses arise by melting and metallurgical treatment of molten metal as a back wash of evaporation, chemical reactions between molten metal and refractory lining, molten metal and air and between molten metal and refining additions. Value of these losses depends on the kind of alloy, on used furnace and charge quality. Except non-returnable losses, the returnable losses creates by melting. They represent a diffe...

The aim of the present research work is to investigate the possibility of adding a mixture of non-granulated blast furnace slag (NGBFS) and steel slag, two wastes resulting from metallurgical industry which underwent calcinations previously, in the raw meal for the production of Portland eco-cement clinker. For this purpose, the NGBFS and steel slag from ArcelorMitall Steel Galati were analyzed for chemical, mineralogical and heavy metals contents. Two samples of raw mixes were prepared, one with typically raw mat...

The possibility to obtain new eco-compatible building materials by milling, pressing and direct sintering of secondary raw materials (SRM) derived from a physical/mechanical treatment of municipal solid waste incinerator (MSWI) bottom ashes is discussed. The chemical compositions and particle size distribution of used SRM press powders were evaluated using XRF analysis and by laser granulometer, respectively. The thermal and densification behaviours were studied by non-isothermal DTA-TG and dilatometric techniques...

Recycling of metals has been becoming an attractive subject, lately due to the fact that the depleted resources, high energy consumption and harmful gases emission. Metal machining chips are recycled conventionaly which consist of melting casting. In the paper the method of direct conversion of bronze and steel chips, into finished product without melting, as an alternative way to conventional method is described. Metal chips were comminuted by mechanical milling and for the next processing the granulated chips la...

Slag are by-products by metallurgical processes. The most famous slag are blast furnace slag and steel slag. Their treatment and using are known and their using is very extensive. Cupola slag formats by cast- iron production in cupola furnace. In some countries it is used by roadway building but in Slovakia it is waste only. In some European countries it is granulated and granulation product is used in building industry. Cupola slag is after tipping from cupola furnace casted in to slag dip and put in to waste dep...

Return material consists of gating, risers and residues from cold chamber, defective castings and another residues from die casting. This material has to be degreased from the fatty and separating agents that are usually of oil origin. In common praxis the clean and contaminated material is put in to melting furnace, it is melted and new alloys are added in the form of small pieces. Within the frame of experiments the influence of contaminated return material in the charge on quality die castings was observed. The...

Waste disposal is the biggest humanity problem nowadays. This has been recognized worldwide and we are lucky because waste treatment is applied, at least at developed countries. On the other hand Nature is suffering a lot and biodiversity is reducing rapidly. The preservation and conservation of Nature has leaded European Union to establish the NATURA 2000 network in continuity of Ramsar Convention. In this paper the conditions and the status of the biotopes of the National Park of East Macedonia and Thrace, and p...

The treatment of natural rock, as well as construction aggregates and ornamental rock creates a great amount of residues, which are usually grain sized under 100 $\mu$m and with chemical and mineralogical composition modified due to processing. Therefore these materials have a composition with a variable content of rock, accompanied with other components as iron particles, clayey materials, flocculants, etc. These contaminants limit the application of those wastes. It is necessary therefore, the search of a proces...

The economic profitability analysis of recycling process should take into account either the minimization of costs connected with the realization of investment or maximization of the production having the costs of the production established. Nevertheless, we need to take into consideration that these costs depend on many factors. In this paper, the economic profitability of municipal waste recycling by the maximization of the production having the costs of the production established or the minimization of the cost...

In the east-coast states of Malaysia, the waste management approach being employed is landfill, but due to rapid development and lack of space for new landfills, the east-coast States in Malaysia is looking for a success recycling of solid waste programmes. Households’ awareness is considered the touchstone for the success of recycling any recycling programmes. However, this paper attempts to identify households’ awareness and opinion on recycling of solid wastes in the major town of Kelantan State which locat...

The legislative framework for the environmental protection in Romania, as a European Union member state, has carried a new approach in the management of the perimeters affected by the industrial activities. At the national level, efforts are made to implement a number of projects (e.g. ISPA [The Instrument for Structural Policies for Preaccession] – Environment) that would lead to a better administration of waste materials associated with these activities (e.g. recycling in the economic circuit or the easy reint...

Smelting of hammerable iron and its treatment in Antiquity and Medieval produced also by-product: slag. Because of small yields of iron the process produced only small amounts of slag that did not attract attention of smelter concerning its possible use. The use of slag pieces was only accidental. The paper deals with the most important processes used for treatment of blast furnace and steelmaking slags and with the most important ways of their utilization. The method of recycling of steelmaking slags, that follow...

This study has for purpose to highlight and eliminate one from problems that influence negativity for the present and future of our environment. Today the environment is a big problem no only in Albania, but everywhere in world. It is very important to save our environment, because one clean environment will say healthy people, secure future.

Industrial processes do not get full efficiency and this means that a considerable amount of wastes without economical aim and which will finish in rubbish dumps, hence promoting a large environmental impact. Modern society steer itself, towards getting a sustainable development which minimize the production of these wastes, which are also increasing its economical, environmental and social costs. This fact compels to search solutions which could avoid the generation of this kind of wastes and to get value from th...

The European foundry industry is the third largest in the world for ferrous castings and the second largest for non-ferrous ones. the annual production of castings in the enlarged European Union amounts 11.7 million tonnes of ferrous and 2.8 million tonnes of non-ferrous castings. The foundry industry is a major player in the recycling of metals. steel, cast iron and aluminium scrap is remelted into new products. The most possible negative environmental effects of foundries are related to the presence of a thermal...

The present work discusses the synthesize of sintered granite–like glass-ceramics obtained by vitrification of hazardous industrial wastes. The chemical resistance of parent wastes and glasses were classified by the toxic characteristics leaching procedure (TCLP), whereas the crystallization behaviour was evaluated by DTA and XRD. The thermal and mechanical properties of final glass-ceramics were also measured and discussed. The obtained glass-ceramics have attractive appearance, elevate chemical durability and ...

The main purpose of this work was to analyze possibilities for application of lignite byproducts- fly ash from Kosova Power Plants in other industry branches and for filling of old underground mines and see the positive impact in environmental protection. The Kosova lignite-fired power generation industry produces millions tones of fly ash each year. Only small amount of this fly ash is used, with most being considered a waste. This waste must be disposed of in an environmentally acceptable way at a cost which is ...

The feasibility to substitute feldspar raw materials in a porcelain stoneware body with waste Cathode Ray Tube (CRT) glass was investigated. Various compositions, containing different percentages of feldspars and CRT glass, were compared. The densification process was studied by non-isothermal dilatometry and the degree of sintering was evaluated by pycnometric techniques. The structure and phase composition of the final ceramics were studied by SEM and XRD, respectively. The technological parameters and the mecha...

Collection, transport, transfer, recycling and proper disposal of solid waste is an essential issue for the local authorities of large metropolitan areas. Turkey, especially in the metropolitan cities like Konya, has been combatting with the same problem, changing the institutional structure of the national policy and the necessary legislation about the solid waste management and the implementation of the recyling-recovery programs to reduce the amount of the solid waste to be disposed of at the sanitary landfills...