The article is devoted to the study of low-grade phosphorites of the Synycheno-Yaremivske deposit in the Iziumskyi district of the Kharkiv region. The possibility of enrichment of this ore by three methods is considered: mechanical, thermal and chemical, carried out in laboratory conditions. The qualitative and quantitative composition of phosphorite has been determined using X-ray fluorescence analysis and electron microscopy with an attachment for energy dispersive analysis. Both natural and enriched raw materials have been studied. Based on the data obtained, it is possible to concentrate this ore with a subsequent increase in the P2O5 content, despite the abnormally large amount of iron.
Methods of plastic waste management, the amount of which is constantly growing due to the high demand for polymer products with high performance properties, are considered. The urgency of the problem is explained by longevity of plastic, which, once in the environment, gradually degrades with the formation of substances dangerous to living organisms. The most common ways of plastic waste management are its storage on specially designated land plots or incineration with / without getting heat. Each of these methods has certain disadvantages, which necessitates the introduction of other measures. Recycling of plastic waste into secondary raw materials, energy or products with certain consumer properties can be the promising method of plastic waste management from ecological and economic points of view. The purpose of this work is to analyze the methods of plastic waste recycling, to establish their advantages and disadvantages, to determine the optimal ways for the disposal of polymeric materials with different properties. Two main groups of polymer recycling methods: physical and chemical, are considered. Physical method includes mechanical recycling, which is based on the physical grinding of plastic waste to obtain secondary raw materials without significant changes in the chemical structure of the material. This process is quite simple in terms of technical design, but requires careful sorting and cleaning of waste, and has limitations on the reuse of recycled material. Chemical recycling takes place through the processes of solvolysis (hydrolysis, glycolysis, alcoholysis) and conversion (pyrolysis, gasification). In this case, the plastic waste decomposes into the original molecules – monomers, from which it is possible to get a polymer product with the same properties. Chemical methods allow disposing of unsorted and contaminated polymeric materials many times without losing their quality. Thus, the introduction of the described methods will reduce the amount of plastic waste, turn them into valuable secondary raw materials and reduce using of natural resources used to obtain primary plastic materials.
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