Nowadays, the sorption-oriented approach is on the agenda in the remediation practices of lands contaminated with heavy metals. The current growing quantity of research accounts for different sorbents. However, there is still a lack of studies utilizing the economic criteria. Therefore, to ensure a wide application of opportunities, one of the necessary requirements is their economic efficiency in use. By utilizing these criteria, this manuscript researches the generally accepted natural sorbents for the assessment of heavy metal ions’ adsorption, such as peat, diatomite, vermiculite and their mixtures in different proportions and physical shapes. The methodological base of the study consists of the volumetric (titrimetric) method, X-ray fluorescence spectrometry and atomic absorption spectrometry. Experimental tests show a certain decline in the efficiency of heavy metal ions’ adsorption from aqueous salt solutes as follows: granular peat–diatomite > large-fraction vermiculite > medium-fraction vermiculite > non-granular peat–diatomite > diatomite.

Digitalization and digital transformation of companies have turned from global trends to an urgent need. Thanks to digitalization and digital transformation, organizations can overcome the times of crisis, the times of lockdowns with less losses and respond more effectively to any adverse changes in the external environment. The assessment of the level of digitalization and digital transformation allows to determine how fast the processes of introducing digital technologies and optimizing processes with digital solutions proceed, both in companies and across the industry as a whole. The article provides an analysis with the systematization of foreign and domestic methods, methodological approaches, methods for assessing the digitalization level and digital transformation, as well as reveals their positive and negative aspects. Based on a comparative analysis, an improved author-developed methodological toolkit is proposed for assessing the level of digitalization and digital transformation, alleviating the disadvantages of the existing methodological experience. The approbation of the author-developed methodological toolkit was performed using the oil and gas industry as an example; the following companies, being the industry leaders, were analysed: PJSC “Lukoil”, PJSC “NK “Rosneft”, PJSC “Gazprom”, and PJSC “Tatneft”. According to the results, the digitalization and digital transformation processes of the domestic oil and gas industry are insufficiently dynamic. It was found that in the period from 2016 to 2020, the Russian Federation industry leaders were in the following order from the most advanced to the least advanced in terms of the digitalization level and digital transformation: PJSC “Gazprom” topped the list; PJSC “NK “Rosneft” was second; PJSC “Lukoil” was the third largest company, and PJSC “Tatneft” held the fourth position.

Nowadays, circular economy (CE) is on the agenda, however, this concept of closed supply chains originated in the 1960s. The current growing quantity of studies in this area accounts for different discourses except the holistic one, which mixes both approaches—contextual and operating (contextual approach utilizes the thorough examination of the CE theory, stricture of the policy, etc.; the operating one uses any kind of statistical data)—to assess the capacity of circular economy regulatory policy packages (CERPP) in operating raw materials and industrial wastes. This article demonstrates new guidelines for assessing the degree level of capacity (DLC) of CERPPs in the operation of raw materials and industrial wastes by utilizing the apparatus of the fuzzy set theory. It scrupulously surveys current CERPPs in three regions: the EU overall, Finland and Russia; and assesses for eight regions—the EU overall, Finland, Russia, China, Greece, France, the Netherlands and South Korea—the DLC of CERPPs in operating raw materials and industrial wastes. The results show that EU is the best in CE policy and its CERPP is 3R. The following are South Korea and China with the same type of CERPP. Finland, France and the Netherlands have worse results than EU with the type of CERPP called “integrated waste management” because of the absence of a waste hierarchy (reduce, recover, recycle). Russia closes the list with the type of CERPP “basic waste management”.

В настоящее время существует большое количество техногенных и вторичных отходов, содержащих золото. Каждый тип такого сырья требует определенного подхода к извлечению благородного металла в связи с особенностями вещественного состава и формой нахождения в нем золота. В работе проведен литературный обзор золотосодержащих производственных и бытовых отходов. Выделено 11 типов техногенного и вторичного сырья, которые производятся четырьмя основными комплексами: горно-обогатительным, металлургическим, бытовым и энергетическим. Для каждого из типов сырья приведены форма нахождения нем золота, размеры его частиц, содержание, примеры месторождений на территории Российской Федерации и методы извлечения золота. Они условно разделены на три большие группы: обогатительные, гидрометаллургические (химическое воздействие) и пирометаллургические (термическое воздействие). Наиболее активно применяются гидрометаллургические методы (в частности, цианирование), так как они выдают высокие показатели извлечения золота - 80-99%. В свою очередь, такие методы нередко оказывают негативное влияние на окружающую среду, они довольно затратные, продолжительные по времени и имеют низкие показатели извлечения микрои ультрадисперсного золота, доля которого значительна, особенно в отходах горно-обогатительного и металлургического комплексов. Обогатительные методы, в свою очередь, показывают эффективность извлечения мелкого золота из отходов горно-обогатительного комплекса. Для извлечения микродисперсного золота наибольшей перспективностью обладают пирометаллургические методы, в частности, плавление рудного материала с последующей продувкой расплава, так как только в расплавленном состоянии возможно укрупнить микрокапельки...

The contamination of natural ecosystems with heavy metals and metalloids (HMMs) primarily results from anthropogenic activities. Consequently, ongoing efforts are dedicated to the development of technologies aimed at restraining the mobility of HMMs and expediting chemical reactions that convert pollutants from mobile to immobile states. Addressing the reclamation issue always necessitates the selection of the most promising and effective type of reclamation work, as well as justification of land prioritization for reclamation purposes. In terms of performance and future potential, the sorbent-oriented approach, grounded in the concept of “green” utilization of man-made waste as a raw material for creating novel composite sorbents, is gaining traction for land reclamation in disturbed areas. In international practice, diverse environmental risk assessment methods are employed to substantiate the necessity for and prioritize reclamation efforts.The aim of the present study is to evaluate established conventional methods for assessing the risks associated with environmental harm. Additionally, this research aims to assess the efficacy and ecological compatibility of the composite sorbents developed by the author. This evaluation will be conducted by assessing and comparing the levels of potential environmental risks or risks of environmental damage subsequent to the application of these sorbents.The objectives of this study are as follows: 1) to explore the theoretical aspects of HMMs: including the formulation of a definition, investigation onto the origins of HMMs, examination of HMMs’ toxicity, and identification of prevalent methods for evaluating the environmental risks associated with HMMs; 2) to evaluate the effectiveness of established methods for assessing the environmental risks posed by HMMs; 3) to assess the efficacy and environmental sustainability of the composite sorbents developed by the author. This evaluation will involve an examination and comparison of the levels of potential environmental risks and the risks of environmental damage subsequent to the a pplication of these sorbents.The research subject: the mining allotment within the Levikhinskoye mine (classified as an environmental disaster site) is investigated as a disturbed land ecosystem, encompassing industrial waste dumps containing HMMs.The research hypothesis aims to establish the viability of “green” waste utilization from industrial sources as a raw material for composite sorbents used in land reclamation, without escalating the environmental damage. The conducted experiments revealed that sorbents composed of peat/water treatment sludge (at a ratio of 20/80 wt. % with natural moisture content) and peat/diatomite/water treatment sludge (at a ratio of 5/15/80 wt. % with natural moisture content) exhibited the highest level of performance, surpassing an overall efficiency of 89%. A sorbent composed of peat/diatomite (at a ratio of 25/75 wt. % with natural moisture content) demonstrated an overall efficiency of 67.7%. The estimated environmental risks (ER and ED) after the application of the proprietary composite sorbents, which include water treatment sludge, exhibited an average reduction of 89.5% and 88%, respectively.