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Waste electronic equipment has become one of the fastest growing waste streams in the world. Mobile phones make up a large proportion of this waste. They cause not only ecological threat, but also a serious waste of resources, including copper. That is why new and effective ways of processing this waste and reusing recovered metals are increasingly being sought. Most modern research on the recovery of non-ferrous and precious metals from mobile phones has focused on hydrometallurgical and biometallurgical techniqu...

According to the current environmental legislation, wooden railroad ties are after the end of their service life considered as a hazardous waste. Various impregnating agents, representing mixtures of distillation fractions (creosote oils) and having a proven carcinogenic character, are used at their production. These agents serve as a wood protection against weather conditions and an attack of biological agents. After the elimination of hazardous impregnating substances, high percentage of quality wood pulp can fi...

Moving towards a circular economy requires well-functioning recycling systems but also the implementation of effective product-life cycle extension schemes such as re-use, repair or refurbishment. A web-based analysis of the websites dedicated to informing the citizen about the private delivery of recyclables to the local recyclables collection centre (recycling centre) was conducted. All cities in Germany with a population of more than 100,000 inhabitants were considered (80 cities in total). Clarity of informati...

In the last decade, many researchers have asked themselves whether it is possible to have a different economic model from the so-called linear one, i.e. to move from the linear to the circular economy. The linear economy is based on the concept that the goods we use must follow a life cycle consisting of three phases. The first phase consists of the extraction of raw materials (or production of agricultural products). The second phase is the transformation of the raw material into semi-finished products. The final...

The area of interest is the synthesis and study of properties of new types of hydrogels made from pelt waste, in order to recover waste from tanneries. The research paper shows that exploratory research as a starting point to obtain new polymeric complex products -multicomponent - called hydrogels, by processing organic waste with applications in agriculture. Hydrogels that are based on biopolymers, compared with hydrogels based on synthetic polymers, have the advantage of biodegradability and a low level of toxic...

Economic analysis was performed for a new process that will be adapted to an existing coal-fired power plant process in order to recycle bottom ash with the objective of obtaining synthetic graphite. Synthetic graphite is a valuable raw material with many industrial applications. It can replace successfully natural graphite, saving capital and environmental costs associated to graphite extraction. Bottom ash resulting from combustion of low quality lignite at a Romanian coal-fired power plant contains significant ...

The waste management is a key factor for sustainable regional and local development. It affects directly to environment ? soil, water, air and etc., which are one of pillars of quality of life and living conditions. The article presents an approach for more easy understanding of the set of statistical data that monitored environment and in particular waste management. The waste management has been analyzed at national, regional and local levels. A share of treated municipal waste of total municipal waste generated...

In this study, three different waste biomass (soy waste biomass, mustard waste biomass and rapeseed waste biomass) resulted after oil extraction, were used as biosorbents for the removal of some heavy metal ions (such as Pb(II), Cd(II) and Zn(II)) from aqueous media. The biosorptive performances of each waste biomass were evaluated as a function of metal ions concentration in aqueous solution and contact time, and the obtained experimental results were modeled using Langmuir isotherm models and pseudo-second order...

The positive effect of mineral additions in cementitious materials (concrete, mortars, composite materials), proven by several studies along time, encouraged a complex research at NIRD ?URBAN-INCERC? Cluj-Napoca Branch regarding the potential valorisation of mineral wastes or by-products, generated by Romanian local industry, in new innovative cementitious materials for the construction industry. The central focus of the research was targeted towards fly ash and its potential use in reliable, high performance ceme...

Chicken meat is easy to produce, and as a result, it is a cheap and massively used source of animal protein in food. However, poultry farms produce more than 200 thousand tons of chicken manure per year, which must be treated. In the large scale farms biological treatment requires huge facilities and investments, therefore other methods are required. Among them, high-temperature drying and pyrolysis. The goal of this work was to compare the products of chicken manure treatment by means of two thermal methods - hig...

The use of recycled polyethylene terephthalate (PETr) in new value-added products is problematic because, during reprocessing in the melt, it undergoes a number of chemical, mechanical, thermal and oxidative degradations, which leads to decreased intrinsic viscosity / molecular mass and implicitly to poor mechanical and thermal properties. In the literature, numerous approaches have focused on obtaining polymer blends using PETr in combination with other thermoplastic polymers. Unfortunately, such mixtures are inc...

In the present work, films based on a potato starch/gelatin composition were prepared with a different ratio of components from 100/0 to 0/100 vol.%/vol.% with increment of 10 vol.% and addition of glycerol as plasticizer. The films were obtained with different drying regimes of the film-forming solutions at 25, 35, 45 and 50 °C for 24 h. For the obtained films the influence of their composition and the drying regime of the film-forming solution on the mechanical properties at puncturing, wettability and water sor...

Today, waste of electrical and electronic equipment is a big problem because it contains heavy metals such as copper, cadmium or nickel that cause neurological diseases. In addition, such waste also contains precious metals such as gold and silver, which makes this material really attractive for recovery. One of the fastest-generated groups of electrical and electronic waste is mobile phones. In 2008, the global sale of smartphones reached the level of 140 million units, while in 2015 it is rapidly growing to the ...

The ability of acidophilic microorganisms to oxidize sulfide minerals is increasingly used in biohydrometallurgical technologies to produce non-ferrous and precious metals from sulfide ores. Strains of Acidithiobacillus ferrooxidans and Sulfobacillus thermotolerans often dominate heap bioleaching processes. Due to their high ability to catalyze redox processes, it has been suggested that they can be used in the technology of microbial fuel cells (MFCs). MFC allows using organic and inorganic waste as a substrate f...

Several research projects of the Department of transportation engineering dealt with the issue of recycling and reuse of various materials into the pavement structure. By recycling and reuse of road construction materials, material and natural resources savings, environmental protection and energy savings were followed. The mixture with reclaimed material, most often reclaimed asphalt pavement (RAP), is of sufficient quality for the new road construction layer and can also affect the resistance to permanent deform...

Metallurgical production generates ferrous waste at every stage of the process. Solid wastes that arise in metallurgical plants include, for example, blast furnace slag, sludge, dust, scale and others. The composition of these materials varies depending on the source of production. The use there fine-grained iron-bearing wastes is possible within a metallurgical cycle. Attention was paid to the possibility of scaling and subsequent use for the blast furnaces. The scales contain mainly FeO, so energy savings occur ...

In this study we examined such a high-keratin-content slaughterhouse by-product as pig bristles and poultry feathers. Our first and most important aim in this research to make a decision about the using direction of a final products. Only after our decision we can determine the most optimal treating and processing method for these slaughterhouse by-products. In our model experiment we can produce different products for example raw materials for cosmetics and petfood products. But the requirements of two main using...

Electronic waste is becoming a serious environmental and economical concern worldwide. The annual growth rate of about 4-5 % in 2016 is one of the fastest growing waste stream in municipal wastes and only about 20% of e-waste is recycled. The rapid growth in the use of electronic equipment caused by various socio-economic reasons has contributed significantly to the generation of large quantity of e-waste. After the use-phase, the electronic devices become electronic waste (e-waste); consequently, it is important ...

Selective non-catalytic reduction of nitrogen (SNCR) oxides is a conventional technology applied extensively to conventional fuel combustion equipment in order to mitigate the emission of such oxides. The results of the process ? NOx concentration in the exhaust gas evacuated and the influence of the SNCR process on the overall combustion process depend on several factors and must be examined in each particular case. The paper presents a comparison between the situation before and after application of the SNCR pro...

This paper proposed an optimized method used for determination of minor elements (Cu, Zn, Mn) from Romanian biomass ash from three different biomass ash using ICP-MS technique. The purpose of the study was to find a suitable method of analysis for the complex matrix of biomass ash by comparing two samples preparation methods: at 5500C and 8200C. For this study the content of metals from three different samples from forestry and related industries (P1), forestry and exploitation (P2) and agriculture (P3) was analyz...

One of the most important alternatives in sewage sludge ash management is the recovery of essential elements such as phosphorus. Phosphorus is an important element for plants, food supply, human health and industry. Phosphorus is a non-regenerative resource and therefore it is important to find alternative sources to recover phosphorus. Phosphorus recovery as struvite (NH4MgPO4.6H2O) from sewage sludge ash has attracted special attention in the last decade due to the potential to be used as an ecologic fertilizer....

The relevance of the results. The experience of the EU countries shows that the process of involving regions in innovative development can be successfully carried out on the basis of "smart specialization" of the regions. A number of specialists consider "smart specialization" as a basis for the formation of both innovation and socio-economic policy. "Smart specialization" of regions allows to achieve 3 main goals: to choose priorities of interregional interaction; to involve in this process various organizations ...

Production of castings plays an important part in the global and in the national economy. The main recipient of the foundry production is the automotive industry, but castings find application also in other branches of industry, in civil engineering, in farming, in medicine, and can as well serve art production. In 2016, worldwide casting production reached 104.1 million metric tons, a shade over the 103.7 million metric tons produced in 2015. The remaining 2015 top 10 casting nations by tonnage are Japan at 5.4 m...

The European Union ?circular economy? aims to maintain the value of products, materials and resources for as long as possible, minimizing the generation of waste by recycling and reusing them [1]. The leather industry generates large amounts of waste, more than 55% of raw material (hides and skin), and over 99% are stored at the landfill [2, 3]. Part of these waste generated are untreated solid waste (hide and skin), meaning around 500-600 kg per ton of raw hides [4, 5]. A way to valorize the untreated hide and sk...

In this article, I will focus on the possibilities of recycling aluminium chips and chips from aluminium alloys. Recycling can be divided into conventional recycling, by remelting the material, or the unconventional method of recycling it in its solid state, in which the chips can be transformed directly into dense bulk materials. The advantages of this method lie in lower energy consumption, reduced metal losses, almost no emissions of harmful gases and minimum waste. In the introduction I will introduce the meth...

jewellery, construction materials, in the mechanical systems and energy generation). The popularity of the use of copper alloys caused an increase in the application of these materials and the increase in the demand for recovery of previously used metals that are components of these alloys. The sources of materials from which the above-mentioned metals are recovered can be: brass scrap, elements from electric furnaces, electronics, car scrap and alkaline batteries. Thus, in recent years, the demand for the recover...

Reverse vending machines (RVM) are a key part of used plastic containers utilization system in Europe and the United States. Waste recognition and sorting in RVM machines can be performed by any of the following procedures: by determining the container material (e.g. using the IR-spectrometer), by recognition of the container type by its shape, or by the barcode identification.[1] These three basic control-procedures make any attempt of the fraud completely impossible. But at the same time, it makes the RVM too ex...

Circular economy has become a world trend, and the only way of economic sustainable development. Waste utilization in concrete technology have much to offer in terms of helping to achieve circular economy goals. Recently various types of waste have been widely recycled as a substitute of fine aggregates in concrete technology. The use of waste as a replacement of natural aggregate is the best sustainable method in order to find alternative ways for conserving the environment. Concrete is the most widely used build...

The global economy needs significant changes that will reduce the high consumption of natural resources and the amount of waste generated. The idea of solving the circular economy proposes a path to solve such problems. Thematically, it covers social, political, economic and production issues. However, it should be noted that Circular Economy is not a ready recipe for solving the problems of depleting raw materials and the deteriorating condition of the environment. The basic premise of Circular Economy is a simpl...

Organic biopolymers represent a source of raw material for agriculture, because the composition of protean wastes provides enough elements to improve composition and rehabilitation of degraded soils. The main target of this scientific paper is investigating the development possibilities for various multicompound systems of biodegradable polymers and studying the effects of these complex products on the structure and chemical and physical characteristics of degraded or contaminated soils (having a poor level of org...

Decreasing fossil fuel resources and the growing attention to environmental causes increased interest in alternative fuels. Currently as a liquid alternative fuels apply: methanol, ethanol, biodiesel (FAME), dimethyl ether (DME). They can be used directly, or as components of mixtures with conventional fuels. Attempts have also been made to apply recycled fuels for diesel engines. As fuel recycling used oils extracted from waste made of polyethylene and polypropylene, oil recycled from used lubricating oils and li...

Packaging waste are one of fastest growing waste streams. Trends in waste generation show an increase in the volumes of waste produced in most countries and it is clear that the trend will continue. Currently, the management of packaging waste represents a major economic and environmental issue throughout the world. Therefore, the proper management, treatment and disposal of packaging waste becomes a pressing problem and a major environmental concern. Due to the fact that, the amount of generated packaging waste, ...

Wastewater management in Poland has a large potential for growth, however, like other countries has to face the new challenges related to the implementation of the circular economy. Innovative wastewater and sewage sludge treatment technologies can bring ecological, social and economic benefits but need to be supported by multi-criteria analyses. This approach has to contend with complex problems which is an important advance in the field of sustainable development and circular economy. This article aims to review...

Municipal waste sludge belongs to a specific type of wastes formed in a process of mechanical, biological and chemical treatment of wastes. The sewage sludge, due to its variable content, constitutes a big problem with respect to optimum and safe sludge management. There is no single correct way to treat sewerage sludge. One needs to remember that the selection of the management method of the formed sludge is individual and depends to a large extends on the size of particular waste treatment plant. A subject of te...

Large amounts of sewage sludge are produced at waste water treatment plants and its disposal is an environmental problem. In this context and in accordance with the European Commission communication on the role of waste-to-energy in the Circular Economy, one of the objectives of Romania Waste Management-Strategy Plan for municipal waste, is incineration of the solid waste in dedicated incinerators, with energy recovery. When the incineration of the sewage sludge with energy recovery is chosen as the final path of ...

Recycling of spoil and demolition wastes is in general complicated process, that require quality processing technology connected with equipment designed for those purposes. During recycling is important factor perfect separation of spoil and demolition waste. Mainly separation of individual components of such waste as glass, plastics, metal parts, wood etc. From concrete, bricks, asphalt and similar construction material. Separated components are utilized by their type. It is necessary to not have dangerous admixt...

Product manufacturing continuously increases despite of complicated relations and unstable world economics. Various forecasts of development in industry show that in future the consumption should not decrease; on the contrary, it should slightly increase. This happens even despite of minimization in industry. But production processes present environmental charging for any company, acting in given sector. Treatment of waste is important for producers of all kind of waste, as well as for consumers that are producing...

Management of used electrical and electronic waste is a huge problem both on a local and global scale. The mass of collected electrowaste in Poland currently reaches approximately 5 kg per one inhabitant, and by 2021 it is to increase to 11 kg. According to estimates, only ca 30-40% of used electrical and electronic equipment in Poland is subjected to recycling. The rest is dumped at scrap yards or is illegally processed in the grey zone. Its considerable part is not processed in accordance with the standards and ...

One of the factors looked upon as an intrinsic constituent contributing to the technosphere as a true phenomenon in the development of the humanity is industrialization. Being powered by fossil fuels, it greatly accelerated urbanization and enabled enormous development in agriculture. The latter could not but be the reason for mass migrations of people to cities which in turn created another positive effect ?urbanization? and ?urban metabolism? coined by Abel Wolman in 1965. The model considered the flow of materi...

This paper considers a field of study related to green value creation in project management and specifically addresses the spectrum of green project managements in Kosovo case, and its impact in developing in general the Kosovo?s economy. During the paper, research questions are related to the role and the importance of green projects management in the country economy. The paper is based on the hypothesis that green project management plays important role in economic development, and also for future business devel...

Tailings are the waste product of mining industry which is usually deposited in the form of slurry. In the present study, laboratory experiments were performed to investigate the permeability properties of coal mine tailings. The investigation includes the compressibility and consolidation behavior of tailings material of different gradations upon application of incremental loads in large size hydraulic consolidometer. The samples were collected from open pit Tur?w Coal Mine in Poland. Remolded samples were manufa...

The property that influences the binding properties of slag is its hydraulicity. The term ?hydraulicity? is now used internationally to describe cements and other binders that set and harden as a result of chemical reactions with water and continue to harden even if subsequently placed under water. There are a few exceptions but these chemical reactions generally involve calcium, silica, and aluminum constituents that react with water to form a whole family of calcium silicate and calcium aluminate hydrates. The c...

In this study, the effect of physical, chemical and mineralogical properties of mine tailings on the microstructural, mechanical and durability properties of cemented paste backfill (CPB) samples prepared with normal Portland cement were investigated. Depending on the characteristics of the tailings, the difference in strength varied in the range of 6-22% between similar types of tailings. However, higher strength values about 61-86% were obtained when the fine material was removed from normal tailings. Porosity v...

In tanneries, only approx. one-third of the total mass of raw hides and skins is converted to finished leather, while two-thirds become either dissolved or solid waste. As part of the natural materials category, usually considered waste, leather fibers introduced into cement mortar panels play a fundamental role in construction due to both insulation properties and mechanical strength. Waste is introduced as a powder or filler or as aggregates in the concrete mix, with energy, economic and environmental benefits. ...

Even if the European Commission estimates that the end-of-life recycling input rate for coking coal is zero, some initiatives proved that coal could play a role in circular economy. Coal-fired power plants still play a significant role in electricity generation although a lot of renewables were developed. Coal combustion produces a relatively small amount of fly ash that is used in cement factories and a large amount of bottom ash that cannot be used in industry because its high carbon content. From this point of ...

The paper aim was to analyze the awareness of eco-labelling on the market, the need for information on the subject and also the type of date which may be considered to be included in the contented. In order to analyze the promotion degree of sustainable development through eco-labelled products, three case studies were analyzed: detergents, household appliances and textiles consumption. Considering that eco-labelled products have a low environmental impact throughout their lifetime, a long utilisation would implic...

One of the possible innovative ways how to process and utilize waste is its pyrolysis in the pyrolysis unit Pyromatic 250. The tests were conducted by Ostravsk? LTS, a.s. in laboratory conditions in the ENET Center of V?B-TU Ostrava. The input material was provided by MEVAPACK, s.r.o. Pyrolysis is a thermal decomposition of organic substances without access of oxygen. This decomposition produces three fractions ? liquid fraction, gaseous fraction and a solid residue. These can be used for heating of the pyrolysis ...

This paper presents a recent study regarding choosing and optimizing of the appropriate test methods to characterization and analysis of used oils from different sectors of activity, in order to evaluate the heavy metal content. In the first step, the samples preparation stage for metal analysis, a number of preparation methods have been tested and finally chosen as optimal, a microwave digestion method. For comparison the metals were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) and atomic abs...

The automotive industry is today a sector that significantly influences and at the same time develops other sectors of the national economy such as engineering, metallurgical, electrical, chemical or construction industries. The paper deals with the possibility of recycling recovery of selected components from vehicles over their lifetime. The authors focus on the components of external vehicle lights (front lights, rear group lights, front fog lights, side direction lights, branding light). It presents its own re...

This article discusses the possibilities of recycling waste material generated using 3D FDM or FFF printing technology and its use in the re-production of printed material. Additive technology is an increasingly popular method for the rapid design of components and machinery parts. It enables creating prototype components and assemblies relatively quickly. This makes it possible to search for the right design of a given component and to choose from several options (e.g. finding the correct shape in ergonomics). Ho...