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The use of secondary waste from municipal solid waste incineration plant in concrete has been studied for its potential to reduce the carbon footprint and abiotic depletion associated with traditional concrete production. Fly ash is a hazardous waste and it can be used as a substitute for cement in the production of concrete. Bottom ash can be used as a substitute for light natural aggregate, which was previously soaked in water for internal treatment of concrete. The composition of concrete includes: CEM I 42.5R, CSA, basalt, sand, zeolite, additives and admixtures. Studies have shown that concrete with secondary waste can decrease CO2 emissions and abiotic depletion compared to traditional concrete. In the article 4 scenarios are introduced (1 - concrete with fly ash, 2 - concrete with bottom ash, 3 - concrete with both secondary waste, 4 - reference concrete). The tests were performed for 1 kg of concrete, in the cradle-to-gate range, excluding transport. 4th scenario has the biggest carbon footprint and abiotic depletion influence. The least impact on environmental has 3rd scenario. Closing the loop by managing secondary waste in concrete fits into Circular Economy and Sustainable Development Goals, especially in SDG 12 - Responsible Consumption and Production and SDG13 - Climate Action. [ABSTRACT FROM AUTHOR]

The rising global average temperature was the main topic at the 26th United Nations Climate Change conference in Glasgow during the climate summit in 2021 (COP26). The meeting aimed to reduce greenhouse gas emissions by 2030 and to discuss the transfer of funds to developing countries. The Europen Green Deal has the same goals. The European Commission aims to achieve climate neutrality by 2050. Climate change has a negative impact on environmental biodiversity, the occurrence of natural disasters, and human health and life. The degradation of the environment is caused, among others, by the extraction of natural resources and the emission of greenhouse gases. Currently, the problem is also the excessive amount of waste and an insufficient number of installations for its processing. In Poland, the greatest problem is with combustible waste, which is stored, while the capacity of final installations is limited. The solution will be the construction of more facilities. The new waste treatment infrastructure will generate more secondary waste. Secondary waste is problematic in management. The largest amount is bottom ash (30% of the batch), but the most burdensome waste is the hazardous fly ash (it is about 3-5% of the batch). Bottom ash is coded as 19 01 12 and fly ash is coded as 19 01 07 *. The management of secondary waste is in the idea of Circular Economy. Thanks to the management of secondary waste, the amount of extracted natural resources and the amount of waste in landfills are reduced. Concrete mixes are an environment that immobilizes pollutants well, therefore they are suitable for containing secondary waste as substitutes for natural resources. Life Cycle Assessment additionally confirms that recycling of secondary waste is compiling with the goals of Sustainable Development and the Europen Green Deal. Thanks to closing the loop, the negative impact on the environment is decreasing. [ABSTRACT FROM AUTHOR]

The paper presents an LCA analysis of biomaterials with particular emphasis on polylactic acid (PLA), as it is recognized as one of the most popular bioplastics on the market. The results show that there are several factors to consider when selecting the best decommissioning option for this type of material in line with the newly introduced circular economy concept, which is the most desirable way to manage waste. A life cycle assessment was carried out to assess the environmental impact of two waste management pathways for PLA, mechanical recycling and composting, compared to the mechanical recycling of PET and PP. The results showed a slight advantage of mechanical recycling of PLA compared to PET and PP, with the composting process having the biggest impact as it does not process the polymer, resulting in the highest environmental impact among the impact categories studied. The analysis was performed using SimaPro software based on the Ecoinvent database. The analysis presents that bio-products are not only eco-solutions but also problems with correct waste management. [ABSTRACT FROM AUTHOR]

In recent years we see a growing interest in renewable and green energy sources. Particularly noteworthy are photovoltaic system PV which can provide us with energy from solar radiation. The most important factor for such an installations is solar insolation. Concentrator technology allows to focus solar light on the surface area of the solar panels which allow us to increase the electricity production. There are many solutions which grant us the possibility to increase the performance of PV installation, for example: tracking mechanism, new materials and hybrid systems. In dye concentrator technology we curve the light and focus it on the surface area of PV system, the position between the concentrator and the solar light can be change by sun-tracking mechanism. By using this type of technology we can decrease the number of silicon parts in the whole installation and by doing this we can reduce the waste streams from the process of the production of silicon cells. Using dye concentrator we can increase the performance of the installation pre square mater of silicon system. The results presented in the paper indicate an increase in the base efficiency of the cells from 15% up to about 20-43% (depends on the proportion between dye concentrator and silicon cells). [ABSTRACT FROM AUTHOR]

The market for electricity production from renewable sources is characterized by very high dynamics of change. This applies not only to total output power, but also to technological changes in waste production and management. Proper planning should prove to be a key issue for implementing the circular economy. Proper environmental assessment is a very important part of the decision-making process. Usually, we used current data to assess the environmental impact. In a rapidly changing environment, this can lead to many mistakes. The solar (PV) market is one of the most important. Cell efficiency increases rapidly and costs decrease. The waste scenario, which should be assessed at an early stage of decision making, can have a significant impact on the EI assessment, and thus consistently on the decision-making process. The use of current data seems inappropriate due to the rapid changes in the technology used to manufacture and utilize PV cells. The assessment of the environmental impact of PV cells on the environment is described in the manuscript. The process is based on a probabilistic approach - which means that the uncertainty of the future is taken into account. Data on current trends in technological change are used during the assessment process to obtain better results and better inform the decisionmaking process. This is a key issue in planning a circular economy. We should take into account not only the current state of knowledge, but based on current trends and possible future state. [ABSTRACT FROM AUTHOR]

Although renewable energy is recently the fastest growing part of energy sector, hard coal still remains the main source of energy in the world. The unwanted side effect of coal production is waste which in large quantities are stored as waste coal heaps. The environmental impact of them could be very high taking to the consideration its life cycle chain. The methodology of environmental assessment of coal industry of heap of coal waste is proposed in the manuscript. Standard impact categories set - usually used in evaluation process - is enriched with new ones which are focused especially on waste management. New impact indicators are proposed in the manuscript. They contain information about quality of waste management in the coal mine, potential emissions, avoided emissions due to change of type of land use etc. In addition the danger of large scale emissions due to random incidental events like uncontrollable burning coal-waste-heap as well as elements of risk assessment is included into the evaluation process as well. [ABSTRACT FROM AUTHOR]