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1.
Forests ; 14(3), 2023.
Article in English | Scopus | ID: covidwho-2292820

ABSTRACT

The COVID-19 pandemic brought a period of high consumption of protective masks and an increase in their waste. Therefore, it was necessary to look at possibilities for their disposal. This article is focused on the disposal of FFP2 masks in the form of pellets blended with sawdust. Further, their ash melting behavior was observed. The method of ash preparation can impact the resulting values of melting temperatures. Therefore, this article investigates the resulting values of ash melting temperatures determined during different ash preparations, such as temperatures (550 °C and 815 °C) and ash size (non-sifted, smaller than 50 µm and 100 µm). All measured deformation temperatures were higher than 1100 °C and even higher than 1200 °C for some samples. Moreover, the presence of FFP2 masks in pellets only insignificantly affected the values of melting temperatures compared to pure wood pellets. The measured values also showed that increasing the temperature of ash preparation from 550 to 815 °C can increase the resulting values of melting temperature. The most significant proportion of the fraction size on the resulting melting temperatures was observed for beech with 5% and 10% of masks at an ash temperature of 550 °C and for spruce with 10% of masks at an ash temperature of 815 °C. © 2023 by the authors.

2.
Energy Reports ; 9:4995-5003, 2023.
Article in English | Scopus | ID: covidwho-2292819

ABSTRACT

The COVID-19 pandemic has caused huge health and economic damages. Various protective face masks, such as single-use, cotton, and the most widespread FFP2 or KN95 masks, are used to prevent the spread of this virus. However, these face masks are usually packaged in plastic packaging, which increases the amount of plastic waste. Plastic gloves are also often used in the connection of the pandemic. All this leads to a large production of protective equipment, but their use contributes to the increase of this type of waste, which presents a new challenge in waste management. This article investigates a complete element analysis of these mentioned materials and observes potential harmful substances. Further, pellets, as a potential fuel for combustion or pyrolysis purposes, were produced with the content of 5% and 10% of face masks. FFP2 were firstly separated from ear straps and wires, then disintegrated, added to spruce sawdust, and compressed into pellets. A series of experiments were realized and aimed at elemental, thermogravimetric, and calorific value analyses of produced pellets. Based on the results, it can be concluded that the presence of face masks FFP2 in pellets increases the content of carbon, hydrogen, and nitrogen, volatile matter, and calorific values, but decreases the content of fixed carbon. According to elemental analysis of produced pellets, no significant amounts of harmful elements were found. © 2023 The Author(s)

3.
Chemical Engineering Journal ; 433(Part 3), 2022.
Article in English | CAB Abstracts | ID: covidwho-2288067

ABSTRACT

The chloroxylenol (PCMX) has shown well virucidal efficacy against COVID-19, but the large-scale utilization of which will undoubtedly pose extra environmental threaten. In the present study, the recycled industrial phenylenediamine residue was used and an integrated strategy of "carbonization-casting-activation" using super low-dose of activator and templates was established to achieve in-situ N/O co-doping and facile synthesis of a kind of hierarchical hyperporous carbons (HHPC). The sample of HHPC-1.25-0.5 obtained with activator and template to residue of 1.25 and 0.5 respectively shows super-high specific surface area of 3602 m2/g and volume of 2.81 cm3/g and demonstrates remarkable adsorption capacity of 1475 mg/g for PCMX in batch and of 1148 mg/g in dynamic column adsorption test. In addition, the HHPC-1.25-0.5 exhibits excellent reusability and tolerance for PCMX adsorption under various ionic backgrounds and real water matrix conditions. The combined physio-chemistry characterization, kinetic study and DFT calculation reveal that the enhanced high performances originate from the hierarchical pore structure and strong electrostatic interaction between PCMX and surface rich pyridinic-N and carbonyl groups.

4.
IOP Conference Series. Earth and Environmental Science ; 1146(1):011001, 2023.
Article in English | ProQuest Central | ID: covidwho-2247386

ABSTRACT

We are pleased to provide you with the proceedings of 2022 4th International Conference on Resources and Environment Sciences (ICRES 2022).The conference was expected to be held during June 10-12, 2022 in Bangkok, Thailand, while the situation of COVID-19 pandemic is unpredictable and unstable. Most of conference participants could not travel to attend the conference venue to do oral presentations. Taking all conditions into consideration, conference committee decided to change physical conference into virtual conference. It was held online by ZOOM application successfully during the same date.The conference was highlighted by four outstanding Keynote Speakers and two invited speakers. Keynote speakers include Prof. Kaimin Shih, The University of Hong Kong, China with his topic "Metal Stabilization and Resource Recovery Examples in Urban Environment”;Prof. Nur Islami, University of Riau, Indonesia who presented a talk on "An Valuable Approach to Study Groundwater Contamination in a Shallow Aquifer System”;Prof. Danny Sutanto, University of Wollongong, Australia who shared a speech on "Solid-State Transformer for Smart Power Grid Applications”;Assoc. Prof. Phebe Ding, Universiti Putra Malaysia, Malaysia who presented a talk about "Role of Postharvest Technology in Producing Quality Fresh Horticultural Produces”. Additionally, two excellent invited speakers, Assoc. Prof. Chunrong Jia from University of Memphis, Tennessee, USA with speech title "Apportioning variability of polycyclic aromatic hydrocarbons (PAHs) in the ambient air in the Memphis Tri-State Area, USA”, and Assoc. Prof. Farhad Shahnia from Murdoch University, Australia with speech title "Recent and Future Research on Microgrid Clusters”.Each normal oral presenter had about 12 Minutes of Presentation and 3 Minutes of Question and Answer. Conference was organized in 5 sessions with various topics: Environmental Management, Waste Utilization and Sustainable Development, Wastewater Treatment, Water Analysis and Hydraulic Engineering, Renewable Energy Technology, Chemical Engineering and Fluid Mechanics, Resources and Environmental Science & Sustainable Development, Energy and Chemical Engineering.All accepted papers presented at the ICRES 2022 were included in this volume, which contained three chapters with topics: (1) Environmental Pollution and Control (2) Waste Management and Utilization (3) Clean Energy and Technology. All papers were subjected to peer-review by conference committee members and international reviewers. The papers were selected based on high quality and high relevancy to the conference scope.We would like to express our sincere gratitude to organizing committee and the volunteers who have dedicated their time and efforts in planning, promoting, and helping the conference. We hope that the readers would gain some valuable knowledge from this effort.List of Committees, Statement of Peer Review are available in this Pdf.

5.
Scientific African ; 16(37), 2022.
Article in English | CAB Abstracts | ID: covidwho-2132290

ABSTRACT

Natural aggregates are being depleted due to the high demand for road and building construction and need to be replaced with alternative materials. This study investigated the potential of using Palm kernel shells (PaKS) as a partial replacement for natural aggregates (NA) and waste plastics (WP) as a binder. The physical and volumetric properties of the different asphaltic mixes (AM) were assessed using the Marshall Method. The bitumen content of the mix design samples was varied from 4.0% to 7.5% of the total weight of aggregates utilized. According to the Marshall parameters, at 5.5% bitumen content, the maximum Marshall Stability value of the different mix designs increased from 9.8 kN to 12.1 kN and the flow value increased from 3.0 mm to 3.7 mm. The experimental results based on the optimum bitumen content determined by the Marshall method demonstrate that PaKS and WP can be utilized to modify AM. However, additional tests will be needed to evaluate the use of this composition in road construction.

6.
Sustainability ; 14(16):9999, 2022.
Article in English | ProQuest Central | ID: covidwho-2024126

ABSTRACT

Global trends influence the approaches and mindset for using natural resources and technological capacities. Participatory scenario methods have proven useful in long-term foresight. However, country-level foresight studies often ignore the broader trends affecting international markets and setting frames for economic development. This study envisions which global trends could occur and how the resulting European policies might affect the Finnish forest sector’s development in 2040. We applied a Futures Wheel approach, where stakeholder groups consisting of policy-, economic- and social sustainability-, technology-, and climate sustainability -experts in the field of forestry and interlinking industries created three future scenarios in a workshop: (1) biodiversity and regulated economy, (2) circular economy, and (3) era of social connection. The scenarios assumed growing resource scarcity as a result of climate change, as well as over-consumption and increasing inequality problems globally. Thus, European-level policies focused on the circular economy and resource-use restrictions. Finnish industries should invest in wood-based side stream and waste utilization to increase added value and decrease virgin wood uses to succeed in these scenarios. However, this would require investments in non-wood energy sources to release these secondary wood flows from energy uses.

7.
Materials (Basel) ; 15(13)2022 Jun 26.
Article in English | MEDLINE | ID: covidwho-1934159

ABSTRACT

Coal gangue is a kind of industrial solid waste with serious ecological and environmental implications. Producing concrete with coal gangue aggregate is one of the green sustainable development requirements. This paper reviews the properties and preparation methods of Chinese gangue aggregate, studies the influence of gangue aggregate on concrete properties and the prediction model of gangue concrete, and summarizes the influence of modified materials on gangue concrete. The studies analyzed in this review show that different treatments influence the performance of coal gangue aggregate concrete. With the increase in the replacement ratio of coal gangue aggregate in concrete, the concrete workability and mechanical performance are reduced. Furthermore, the pore structure changes lead to decreased porosity, greatly affecting the durability. Coal gangue is not recommended for producing high-grade concretes. Nevertheless, pore structure can be improved by adding mineral admixtures, fibers, and admixtures to the coal gangue concrete. Hence, the working properties, mechanical properties, and durability of the concrete can be improved effectively, ensuring that coal gangue concrete meets engineering design requirements. Adding modified materials to coal gangue concrete is a viable future development direction.

8.
Aerosol and Air Quality Research ; 22(5), 2022.
Article in English | ProQuest Central | ID: covidwho-1835304

ABSTRACT

This article examines the correlation between the amount of pollutants emitted from medical waste incinerator plant and the number of COVID-19 infections, based on the example of Podlaskie Voivodeship in Poland. This paper deals with the issues of medical waste management during the COVID-19 pandemic. Thermal processing is characterised as a method of medical waste utilisation. The technological sequence of the medical waste incineration installation and the integrated exhaust gas cleaning system are discussed. The results of studies on the emission of pollutants into the atmosphere during combustion are compared with the number of COVID-19 cases in the same voivodeship to investigate how the coronavirus pandemic affects the amount of medical waste generated, thus the amount of pollutants emitted into the atmosphere. The Pearson's linear correlation coefficient and the Student's t-test are used to verify the results. The analysis results show a statistically significant, moderate positive correlation between the amount of covid waste and the number of COVID-19 cases (0.5140). In turn, there is also a statistically significant moderate correlation between the number of COVID-19 cases and emissions of SO2 (r = 0.6256, p = 0.010), NOx (0.5019, p = 0.048), and HCl (0.5130, p = 0.042). This correlation finding highlights additional costs to the environment and public health as the number of COVID-19 cases increase, which can be taken into account for pandemic planning by governments in the future.

9.
TIP Revista Especializada en Ciencias Químico-Biológicas ; 24(41), 2021.
Article in Spanish | CAB Abstracts | ID: covidwho-1780395

ABSTRACT

Many modern human activities rely greatly on plastic foams, whose consumption and production have considerably increased in the past decades. The use of plastic products has had positive impacts on human general welfare;however, the negative effects derived from their inappropriate disposition have become a major concern, especially during the current COVID-19 sanitary emergency, in which the utilization of single-use plastics has rapidly increased. Although some plastic polymers such as polyethylene (PE) and polystyrene (PS) can be recycled, the high demand for energy and technology, the use of potentially toxic substances and the low profitability of the process, make this option non-optimal. In this situation, biological treatment of plastic waste is emerging as a promising alternative and the use of PE and PS-eating organisms, such as mealworms and waxworms, has attracted the attention of researchers around the world. The aim of this review is to synthesize the most recent advances in the field of plastics polymers degradation by insects larvae and an analysis of the current and future trends of this developing research area.

10.
Journal of Food Measurement and Characterization ; 16(2):1559-1571, 2022.
Article in English | CAB Abstracts | ID: covidwho-1748433

ABSTRACT

Interest in the biological role of bioactive compounds present in plant by-products has increased over the last few years. This study aimed to investigate the nutritive value and biological activities of Egyptian Grape leaves (GL), Grape seeds (GS) and Mulberry leaves (ML), as well as investigate the impact of P-irradiation for improving the utilization of these plant by-products. The dose level 5.0 kGy showed highest the content of crude protein (24.42, 19.41 and 13.50 mg/100 g), as well as crude fiber (34.26 and 21.18 mg/100 g) for ML, GL and GS, respectively. Mulberry leaves has a highest content of protein and fiber at dose 5.0 kGy compared with GL and GS. The highest total phenolic content was found in GS (9.75 mg/g DW), followed by GL (7.32 mg/g DW) and the lowest in ML (5.97 mg/g DW). While ML had a higher total flavonoids content (5.61 mg/g DW) than GS (4.88 mg/g DW) and GL (2.86 mg/g DW). Total phenolic and flavonoid contents were significantly increased at 5.0 kGy. The highest level (83.25% and 80.24%) of scavenging activity (DPPH %) and inhibition activity of HCT 116 cells was recorded at 5.0 kGy by GS. All extracts irradiated at 5.0 kGy exhibited varying degrees of antibacterial activity against (Gram+ve and Gram-ve), the GS followed by GL then ML showed strong antibacterial activity with a diameter of inhibition zone of 26.2, 24.5 and 19.7 mm, against L. monocytoganes, respectively and 24.4, 21.4 and 17.2 against S. typhimurium, respectively. This study suggests that P-irradiation is an effective technique to enhance the recovery of phenolics and flavonoids from GL, GS and ML. Also in current study, antioxidant, antibacterial and anticancer activity has been suggested to appear a clear positive relationship with the total phenolic material. This study has proved that the Egyptian GL, GS and ML are rich sources of valuable phytochemicals and nutrients that can serve as a potential source of nutraceuticals and multifunctional food additives (antimicrobial, antioxidant, and anticancer). Phenolic compounds recovered from GL, GS and ML may have a potential role in fighting the COVID-19.

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