With the outbreak of the COVID-19 pandemic, the waste management sector had to face new challenges, e.g., changes in the size and composition of the waste stream, or the presence of potentially infectious waste. This article is based on a case study in Poland. The data analysis showed that the increase in municipal waste mass during the pandemic did not differ from statistics observed in previous years and ranged from 0.3 to 0.5 million tons per year. Lifestyle changes caused a decrease in the amount of waste generated outside households. Social migrations contributed to rapid changes in the mass of waste generated in selected agglomerations by up to 80 kg/capita. In the waste stream, significant amounts of specific groups of waste related to the pandemic (“corona waste”) as well as packaging and food waste were noted. Despite the pandemic, in 2020, Poland recorded an increase in selective waste collection by 6.7 percentage points (pp.) Data on municipal waste management showed an increase in the mass of waste sent for recycling by 0.7 million tons, while the mass of landfilled waste decreased by 0.3 million tons. The observed positive changes in waste management allow the implementation of sustainable development assumptions to a greater extent.

The growing demand for lithium, driven by its crucial role in energy storage technologies such as lithium-ion batteries for electric vehicles, renewable energy storage, and portable electronics, is intensifying the need for sustainable extraction methods. While lithium is sourced from both primary and secondary resources, particularly from recycled materials, the recovery from spent lithium-ion batteries remains challenging. This article presents acidic reductive leaching as a promising alternative for lithium extraction from secondary sources and unconventional ores, emphasizing its potential benefits, such as higher recovery rates, faster processing, and adaptability to various waste materials. Notably, this method facilitates the selective recovery of lithium before cobalt and nickel, providing a strategic advantage. This study highlights the lack of optimization studies on leaching conditions (e.g., acid concentration, reducing agents, temperature, and time) that could maximize lithium recovery while minimizing environmental and economic costs. The article aims to investigate and optimize the parameters of acidic reductive leaching for more efficient lithium recovery. Additionally, the results contribute to the principles of the circular economy and sustainable supply chains in the energy sector, providing a method to reduce dependency on geopolitically constrained lithium resources and supporting the global energy transition toward cleaner energy solutions.

Energy transition is one of the basic actions taken to counteract and prevent climate change. The basic assumption of energy-related changes is its sustainable use according to the closed-loop model, as well as moving away from fossil fuels, in particular from coal, the combustion of which contributes to excessive harmful carbon dioxide emissions. One of the most popular solutions towards green energy is nuclear energy. Its use allows for a significant reduction in greenhouse gas emissions harmful to the environment and climate, but it also involves the generation of radioactive waste that requires appropriate processing. This paper presents the results of the flotation removal of barium(II) ions from a dilute aqueous solution using ionized acyclic polyethers. The basic factors determining the efficiency and kinetics of the process were defined. It has been shown that as the acidity of the attached polyether molecules increases: the flotation rate constant 1 (0.1667 min⁻¹) < 3 (0.2468 min⁻¹) < 2 (0.3616 min⁻¹) and the separation degree Ba²⁺: 1 (86.8%) < 3 (99.3%) < 2 (99.4%). The presented results of ion flotation tests may facilitate the collective or selective separation of radioactive isotopes, i.e., Cs-137, Sr-90, Ba-133 and Co-60, from radioactive wastewater in the future. The results of the experimental work described in the article can also be used to develop individual processes for separating mixtures of radioactive isotopes (radioactive wastewater) into individual components (isotopes) and subjecting them to subsequent transformation processes. The obtained results allow us to claim that the tested organic compounds can be used in the future in the selective treatment of hazardous wastewater, which will translate into a reduction in unit costs of industrial processes. The selective recovery of individual pollutants is the basis for the next step in waste management, i.e., designing a cheap method of waste disposal, which also directly affects the economics of the process and its use in industrial conditions.

Cemetery waste (CW) constitutes one of the streams of municipal waste (MW). Based on the available data, it can be said that it accounts for about 1% of the mass of MW being generated in Poland. CW management should be carried out selectively. It is estimated that the level of CW selective collection is lower than the average level achieved for MW. This paper presents some solutions concerning the selective collection of CW implemented in selected municipal and denominational cemeteries in Poland. Based on research conducted, the levels of proper separation of glass and biodegradable waste in containers for their selective collection were determined, accordingly as >85% and >80%. Due to the contamination with paraffin residues, the purity of the selectively collected plastic fraction was lower than 20%. The human factor was recognized as the most significant determining efficiency of the selective collection of CW. Therefore, further education of society, as well as promoting good practices in the field of CW management, should be regarded as desirable.

The annual amount of cemetery waste in Wrocław does not exceed 1% of generated municipal waste. The largest amount of cemetery waste is generated in autumn months. For the Osobowicki cemetery, the total volume of containers for selective waste collection has doubled since 2013 and now constitutes 49% of the total volume of containers. Research of the content of selected waste containers revealed the segregation of glass, plastics and biodegradable waste in the range from 81% to 92%. For the St. Lawrence cemetery the volume of containers for selective waste collection constitutes only 6% of the total volume of containers there. Despite these difficulties, the degree of separation of glass and plastics is very high (from 89% to 94%). Increase of the volume of containers for biodegradable waste would reduce the high share of green fraction (from 22% to 38%) in non-biodegradable waste containers.

Refuse-derived fuel (RDF) is one of the municipal waste processing products generated inmechanical-biological installations. The RDF production allows energy recovery while reducingthe mass of landfilled waste. RDF is produced mainly from mixed waste stream with combustibleproperties. Currently, the main recipient of RDF fuels in Poland is the cement industry, whichaccepts only high-quality fuels. Annually a reduction of combustible waste share in the pre-RDFfraction intensifies difficulties in producing fuels with a sufficiently high calorific value. However,due to the energy transformation, it is planned that RDF would also be used in the heating sector.A positive aspect of this situation is the emergence of alternative recipients of RDF, even with theirlower calorific value. This may improve the market situation of RDF and reduce operation costs formunicipal installations in the long-term perspective.