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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...