As a result of rice grain processing, a big amount of waste (up to 20%) is produced. It is mainly rice hulls. The main components of rice hulls are cellulose, lignin and mineral ash. The mineral ash quantity in rice hulls varies from 15 up to 20%, by weight of the rice hulls. The mineral ash consists of amorphous silica (opal-type). Due to the high content of silica in rice hulls, the material burns with difficulty under natural conditions, and it is biodegradably destroyed only with difficulty, when composted. Utilization of rice hulls then becomes an ecological problem due to huge rice production and its continuous growth. At the same time, the annual quantity of silica content in rice hulls is comparable with the quantity of amorphous silica produced as a mineral resource. The issue of manufacturing cellular glass silica construction materials from rice hulls as a renewable resource is discussed in this paper. The utilization technology is based on an amorphous silicon oxide with the use of energy from the combustion of the organic component of rice hulls.

Several million tons of end of life tires (ELTs) are piled annually as a result of human activities. Various methods have been proposed for the extraction and recycling of the resource potential of ELTs. The chemical composition of ELTs seems to enable their usage as a fuel after mechanical separation of a steel cord. Indeed, in the rubber of ELTs, up to 90 mass% accounts for carbon and hydrogen. Currently, it is by incineration that a significant proportion of ELTs is utilized. However, ELTs contain not only sulfur, which is used for vulcanization, but also nitrogen-containing additives. The behavior of these heteroatoms during oxidation is poorly investigated. It has been shown that the pyrolysis liquid fuel obtained from ELTs contains such sulfur compounds as mercaptans and nitrogen in the form of hydrocyanic acid and cyanogen. Deep oxidation of ELTs results in the oxidation of sulfur compounds to dioxide, but the oxidation products have been found to contain traces of cyanogen. Taking this into account, one should pay attention to the ways of transforming heteroatoms during the process of ELT oxidation and the products of ELT pyrolysis as potential sources of highly toxic gas emissions.

Thermotechnical properties of municipal solid waste (MSW), in particular their moisture, ash content and heating value, determine the effectiveness of methods of thermal utilization of waste, interest in which is currently growing in Russia. The MSW heterogeneity leads to difficulties in determining their thermotechnical properties and causes the urgency of carrying out complex researches of MSW fractional and component composition with the isolation of sufficiently homogeneous components, the selection and laboratory researches of samples of such components. The article presents an approved methodological approach to MSW analysis, which includes full-scale field investigation of MSW component and fractional composition and analysis of their moisture and ash content in a laboratory with the subsequent calculation of the thermotechnical properties of the MSW flow as a whole. A distinctive feature of this approach is the provision of representative samples of MSW and individual components, consideration of seasonal and weekly fluctuations in waste composition, as well as the allocation of a large number of MSW components and separate investigation of their moisture and ash content in fractions of different sizes. Moisture and ash content of individual components within the same category differ significantly from each other and depend on the component's material, properties and size. Heating value an individual component category depends on the component composition within the category and vary with the same water and ash content of the individual components. The obtained results allow modeling of MSW composition, heating value and other properties after different treatment technologies, including mechanical, manual and optical sorting, and select technologies and equipment for achieving specified waste quality parameters.

Актуальность работы определяется требованиями экологической безопасности при строительстве на территориях с выявленным техногенным загрязнением почв. В работе рассматривается применение хромато-масс-спектрометрии в исследовании загрязнённого грунта с целью идентификации продуктов трансформации в природных условиях многокомпонентных рецептур смазочно-охлаждающих жидкостей. Выполнена идентификация и поиск по масс-спектрам компонентного состава продуктов трансформации индустриального масла, предложено маркерное соединение. Показана возможность идентификации на основании регистрации масс-спектров ионов химических соединений, определена структура и элементный состав. Поиск характеристических ионов органических соединений выполнялся с помощью банка библиотеки масс-спектральных данных. Установлены характеристические ионы (основной и подтверждающие ионы), характеризующие структуру химических соединений и определено хроматографическое время удерживания. Для оценки миграции маркерного соединения выполнено его количественное определение методом капиллярной газовой хроматографии в пробе воздуха и пробах загрязнённого грунта; исследованы образцы грунта у основания ёмкости, образцы маслоудерживающей ткани и фильтрат из поддона. Результаты исследования направлены на обоснование методики оценки загрязнения промышленных площадок смазочно-охлаждающими жидкостями с учётом трансформации органического загрязнителя и рекомендаций по рекультивации загрязнённых...

The aim was to review and analyze Russian and foreign research works, legal, regulatory and methodical documents that focus on investigating fine-dispersed particles in ambient air considering their influence on human health and external management of emissions. The materials were searched for in relevant databases including WoS, SCOPUS, eLIBRARY; we also examined legal, regulatory and methodical documents available at web-sites of the WHO, Russian authorities and relevant authorities of several foreign countries. Multiple epidemiological and laboratory investigations confirm substantial health hazards posed by particles smaller than 10 µm (РМ10, РМ2.5). There is evidence that fine-dispersed fractions are a persistent component in emissions from industries, energy-producing facilities, and transport. The Russian methodical base for considering fine-dispersed dusts in emissions requires upgrading and improving as regards mandatory РМ10 and РМ2.5 inclusion into methods for identifying emission structures. It is also necessary to develop and approve methods for quantification of fine-dispersed particles in industrial emissions. Access to calculation and instrumental methods for establishing РМ10 and РМ2.5 masses in emissions allows correcting inventories of emission sources and proper state regulation of emissions through establishing safety rations of sufficiency of sanitary protection zones around enterprises. It also allows creating a more qualitative system for setting emission quotas where priority chemicals are identified on the basis of assessed health risks considering substantial contributions often made to them by fine-dispersed particles.