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Improving the performance of the gypsum binder is possible by strengthening the gypsum matrix. The increase in strength is ensured by the introduction of a complex of mineral and chemical additives. The use of waste as components of such a complex solves a set of problems. The market is saturated with competitive and high-quality materials. Designed materials meet modern requirements. In addition, the problems of waste disposal, freeing up space, environmental protection and reducing the resource intensity of prod...

Arsenic (As) and antimony (Sb) are elements with similar chemistry and geochemistry, but their environmental risk differ depending on the origin and degree of the pollution. As and Sb are both very toxic, particularly their inorganic substances in the oxidation states of III and V, which also represent the most common As/Sb forms in the environment. In environmental systems, As mostly occurs as the tetrahedrally coordinated, pentavalent arsenate AsO43- (in oxidising environment), and the trivalent arsenite AsO33- ...

The European Union (EU) is hurrying towards a climate-neutral economy, which includes increasing the use of renewable resources, including wood for heating. This direction means that the use of wood is increasing every year in the EU and beyond. The by-product of this activity, biofuel ash, is correspondingly increasing, so its further use should be considered a long-term issue. Energy producers face the challenge of making the best use of ash and often landfill it, thus moving countries further away from the EU D...

The worldwide olive oil sector is a strategic sector for olive oil producing countries due to olive oil nutrition and health benefits. With what is being produced of olive oil, it continues to produce wastewater with a significant environmental impact due to the high organic load and the biochemical composition of this wastewater, particularly, the presence of microbial growth inhibiting compounds such as phenolic compounds, which makes its biological treatment difficult. On other way, red mud, the main leaching r...

In Russia, turning to the circular economy concept is becoming a new wing of theenvironmental industrial policy. In most Russian regions, the necessity of recyclingindustrial waste co-exists with the challenges of municipal waste management. Thus,according to the official statistics, the amount of solid waste formed in 2019 reached7.75 bln tons, 55-60 mln tons being categorised as municipal waste. In 2010-2019,annual waste generation grew from 3.74 to 7.75 bln tons; about 15 thousand landfillsoccupy the territory ...

The work is devoted to the study of fuel ash as components of composite cements and building mixtures based on them. The use of bottom ash as raw material is an urgent problem. On the one hand, their use in production solves the issue of creating resource and energy saving technologies and increasing the efficiency of cements and concretes. The use of ash makes it possible to improve the properties of cements, bricks, products from aerated and heavy concrete, light aggregates, and the quality of road construction....

As a result of the operation of thermal power plants used solid hydrocarbon fuel, ash and slag waste (ASW) is formed. ASW is a finely dispersed mineral material remaining as a result of burning brown and hard coal. The involvement of ASW in industrial turnover is one of the most effective ways to solve the issue of energy and resource conservation. The share of involvement of these types of waste in economic turnover in the European Union is about 98%, in China about 80%, and in Russia this indicator does not exce...

Powdered waste sludge from the production of technical stone (TSW), produced by theTechniStone® Company (Hradec Kralove, Czech Republic), was surface modified withFe2+ and Mn2+ inorganic salts and then testified as a potential adsorbent ofenvironmentally important oxyanions (phosphate PO43-, arsenate AsO43- and chromateCrO42-) from contaminated waters. The surface modification in principle consisted increating a thin layer of hydrated Fe/Mn ions in reactive form on the TSW surface.Thanks to the change of the surfa...

The production of tiling and building ceramics is based mainly on the traditional system clay-silica-feldspar. However, in recent decades it has been demonstrated that some of these raw materials can be successfully replaced by various industrial wastes. Because of the high feldspars price a significant part of these studies was based on the usage of different alternative “amorphous” fluxes (as glass culets, TV cathode ray tubes, basaltic tuffs and others). Unfortunately, the addition of similar materials in amoun...

The article focuses on the development of an industrial policy towards modernization ofthe resource-intensive sectors of Russian economy based on the principles of BestAvailable Techniques (BATs) and secondary resource recycling (recovery). BATs areregarded as benchmarks for the regulators as they draw up mandatory requirements forthe industry. This way industries would be motivated to introduce innovations andimplement modernization programs, while the regulators should set targets for such atransformation. The m...

The paper presents an LCA analysis of biomaterials with particular emphasis onpolylactic acid (PLA), as it is recognized as one of the most popular bioplastics on themarket. The results show that there are several factors to consider when selecting thebest decommissioning option for this type of material in line with the newly introducedcircular economy concept, which is the most desirable way to manage waste. A lifecycle assessment was carried out to assess the environmental impact of two wastemanagement pathways...

Solutions to the environmental problems associated with the burning of coal in power plants are in poor condition. One of the main problems is the continuous growth and accumulation of ash and slag waste (ASW). Ash and slag waste is a major source of raw materials for various industries. However, the degree of use of ash and slag waste at Russian thermal power plants does not exceed 2 million tons / year, with an annual output of 25-28 million tons. Modern methods of enrichment and processing allow the use of ash ...

The paper focuses on management tools that are used in project work leading to the construction of a new sorting line for municipal waste treatment. The aim of the article was to describe possible project management tools that are used in the management of the company and individual project phases and activities. The construction of a modern waste sorting facility responds to a change in EU and Czech directives. This area is so specific that it cannot be affected by the situation around the COVID 19 pandemic, whic...

Current context in which the emphasis is on promoting the circular economy, due to environmental policies, the food industry is constrained to develop new strategies to reduce food waste. The beer industry generates significant amounts of by-products that are often incorporated into animal feed or aquaculture. Yeast, the second by-product of the brewing process is generated in large quantities of 1.5 kg to 3 kg/100 L of beer produced. By using various purification processes, the residual brewer's yeast can be easi...

The largest manufactures of glass-ceramics in the last decades are related to the luxurious Japanese tiling material “Neoparies" and its replicas, developed in China. These marble-like materials are produced by sintering and surface crystallization of glass grains (frit) with original composition, placed in large refractory moulds (up to 1-2 m2) and the subsequent grinding and polishing of final panels in use. Since these products are manufactured in high volumes, the technology seems to be very appropriate for sy...

The materials used for the synthesis are modified waste raw materials in the form of slags (up to 70 % wt.) with addition of quartz sand and calcium fluoride. The initial batch is being melted at 1400 oC and then quenched in water. The resulting glass frit is milled bellow 75 microns, pressed into “green” samples being exposed in a next stage to thermal scanning at different temperatures with different heating rates, holding temperatures and times. In the framework of present investigation is presented analysis of...

Solid-state dissolution by sintering in the presence of Na2O2, a strong oxidizing agent, isreported in the present study as a preparatory procedure prior analysis by ICP-MS. Theadequacy of the combined procedure for the purpose of identification of potentialsecondary sources for REEs from difficult matrixes like, for example, mining wasteswas investigated. The method was applied to Certified Reference Materials (CRMs)with silicate-rich complex matrices, namely rhyolite, and granite. From each materialtwo sample we...

In the article synthesis of structures of disperse systems on the basis of gypsum is considered. Such systems are necessary for receiving materials which exclude burning of raw materials on the basis of gypsum waste for the receiving binders. For them use a certain composition of raw mix. Selection of structure of compositions allows to increase properties of materials. Such materials are characterized by high strength. The process of formation of structure of a gypsum which is received by hyper pressing is studie...

Waste recycling and the circular economy are among the most important issues in the European Union strategies. Because Romania has yet to meet many requirements of the European Commission?s policies, there have been opened several infringement proceedings against our country for pollution, wood management, and waste management. In May 2018, the European Commission sent a letter urging Romania to take major actions, such as: to close, seal, and ecologically restore 48 illegal landfills, and to comply with the judgm...

Recycling of asphalt is an important technological process applied worldwide. The strategy is to use as much milled, ripped or broke asphalt material into the new mixture. With the correct technological design, the maximum appreciation of this material is achieved. Due to the dominant use of asphalt mixtures in pavements, it is important to address the possibilities of their recycling. At present, a sufficient amount of reclaimed asphalt with good potential for further use is available in Slovakia. The problem is ...

The present study has been dedicated on the removal process of heavy metal ions from electrolyte solutions by using methods of electroflotation and subsequent filtration in a multi-component system with the presence of various surfactants of different nature. The research was conducted in a five-component system comprising ions of iron (II), nickel (II), copper (II), plumbum (II), and zinc (II) (the total concentration of metal ions is 200 mg/l). The research was conducted in a highly concentrated electrolyte solu...

Taking into consideration limited financing of waste processing industry in Russia, refuse derived fuel production is becoming a promising course to decrease MSW landfilling at minimum cost, as the method allows safe energy recovery in existing cement kilns and precalciners. For its part, the cement industry pursues a lower level of fuel expenditure, which accounts for about 20% of total production cost. In this regard, fossil fuel substitution for fuel from waste is a mutually beneficial solution, linking the int...

The physical and chemical characteristics of sludge from the chrome production in the Donskoy Ore Mining and Processing Plant (DOMPP) owned by TNK Kazchrome JSC have been studied. Researches have been performed to determine the gravity concentration ability of sludge tailings using fractional analysis, concentration tables. It was found that it is required to classify the initial sludge into size classes to obtain high technological parameters, and beneficiation with screw separators is ineffective. New data have ...

The paper deals with the pressing issue of energy saving in the production activities of forest companies. We see the solution to this problem in involving renewable energy sources to production. However, in most cases, the drying and thermochemical processing technologies used at enterprises are not able to meet modern requirements for energy consumption, environmental friendliness, and efficiency. To supply heat and electric energy to vegetable biofeedstock drying equipment, a self-contained complex energy-savin...

Waste disposal and management is one of the urgent issues faced by mankind at the current stage of development. Waste car tires pose a significant threat to the environment, which makes their efficient processing particularly important, as the volume of this type of waste generated each year worldwide is estimated at more than 10 million tons, of which 1 million tons are produced in Russia. A review of the car tire, wood, textile, and plastic pyrolysis products is presented. The products of pyrolysis include pyrol...

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...

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 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...

The article describes an information-analytical system for assessing the impact of solid waste landfills on the environmental. The proposed system can be an informational basis for creating a national register of municipal solid waste, both authorized, acting in accordance with the requirements of current legislation, and unauthorized dumps. This basis will provide a scientific and economic justification for making decisions on the prospects for the management of municipal solid waste at the regional and local lev...

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...

After the end of use, they become e-waste and are recycled or put on the landfills. Recycling rate of e-waste in Slovakia was in 2017 according to Eurostat only 36.7 %. Recent studies show that yields from e-waste (mainly computers, mobile phones) are much higher than in metal ores and thus can be considered as valuable secondary sources of precious and base metals. In presented paper five different parts of computer e-waste were investigated for possible gold recovery, namely CPUs, CPU sockets, BGA chips, pins fr...

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...

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 ...

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...

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...

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, ...

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...

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...

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...

In this study, the potential use of dam tailings (DT15 m., DT40 m., DT65 m.) of a copper mine for paste backfill material was investigated. Cemented paste backfill (CPB) samples were subjected to the uniaxial compressive strength (UCS) test at 7-14-28-56-90-180 days of curing ages. A total of 378 CPB samples were prepared at different binder dosages of 5.5?11.0 wt% by dry weight to determine an optimum CPB mixture with a target UCS of ?1.0 MPa over a curing period of 28 and 90 days. The strength development of CPB...

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 ...

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...

Widespread use of natural stones has been a habit that has been going on for centuries. In addition to this widespread use, this material causes a significant amount of waste materials to be exposed during the processing of these materials. This is an economic problem in terms of both environmental pollution and disposal in waste materials. Therefore, the evaluation of these natural rock wastes is an important issue. In this study, it is aimed to recover the waste materials in natural stone workshops in Kahramanma...

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...