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1.
Chemical Engineering Journal ; 451:138603, 2023.
Article in English | ScienceDirect | ID: covidwho-1982695

ABSTRACT

In accordance with global economic prosperity, the frequencies of food delivery and takeout orders have been increasing. The pandemic life, specifically arising from COVID-19, rapidly expanded the food delivery service. Thus, the massive generation of disposable plastic food containers has become significant environmental problems. Establishing a sustainable disposal platform for plastic packaging waste (PPW) of food delivery containers has intrigued particular interest. To comprise this grand challenge, a reliable thermal disposable platform has been suggested in this study. From the pyrolysis process, a heterogeneous plastic mixture of PPW was converted into syngas and value-added hydrocarbons (HCs). PPW collected from five different restaurants consisted of polypropylene (36.9 wt%), polyethylene (10.5 wt%), polyethylene terephthalate (18.1 wt%), polystyrene (13.5 wt%), polyvinyl chloride (4.2 wt%), and other composites (16.8 wt%). Due to these compositional complexities, pyrolysis of PPW led to formations of a variety of benzene derivatives and aliphatic HCs. Adapting multi-stage pyrolysis, the different chemicals were converted into industrial chemicals (benzene, toluene, styrene, etc.). To selectively convert HCs into syngas (H2 and CO), catalytic pyrolysis was adapted using supported Ni catalyst (5 wt% Ni/SiO2). Over Ni catalyst, H2 was produced as a main product due to CH bond scission of HCs. When CO2 was used as a co-reactant, HCs were further transformed to H2 and CO through the chemical reactions of CO2 with gas phase HCs. CO2-assisted catalytic pyrolysis also retarded catalyst deactivation inhibiting coke deposition on Ni catalyst.

2.
International Journal of Energy Research ; 46(1):5-5, 2022.
Article in English | Academic Search Complete | ID: covidwho-1598737

ABSTRACT

We would also like to take this opportunity to thank Prof Dr Ibrahim Dincer and the editorial team of Wiley, all contributing authors, reviewers, and our assistants for their efforts that have made this special issue a true success. All articles in this special issue on "Sustainable Energy Technologies" were subjected to another round of peer-to-peer review processes for further quality improvement prior to publication. The industry, transportation, and building sectors will need to use more sustainable energy. [Extracted from the article] Copyright of International Journal of Energy Research is the property of John Wiley & Sons, Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

3.
J Hazard Mater ; 423(Pt B): 127215, 2022 02 05.
Article in English | MEDLINE | ID: covidwho-1415557

ABSTRACT

The increasing awareness of waste circular economy has motivated valorization strategies for minimizing resource consumption and waste production in the private sector. With the rise of various industrial wastes and with the emergence of COVID-19 wastes, a sustainable approach is needed to mitigate the growing concern about wastes. Thermochemical treatment technologies in the form of direct combustion, torrefaction, pyrolysis, and gasification have been identified to have vital roles in the value-creation of various waste streams. Moreover, the alignment of thermochemical processes for waste mitigation concerning the circular economy framework needs to be established. Accordingly, a comprehensive review of the different thermochemical treatment options for industrial and the novel COVID-19 medical wastes streams is conducted in this study. This review focuses on highlighting the instrumental role of thermochemical conversion platforms in achieving a circular economy in the industrial sector. Various strategies in waste mitigation through various thermochemical processes such as management, recovery, reduction, and treatment are discussed. The results show that thermochemical technologies are beneficial in addressing the sustainability concerns on mitigating wastes from the industrial sector and wastes brought by the COVID-19 pandemic. This also includes the current issues faced as well as future perspectives of the thermochemical conversion technologies.


Subject(s)
COVID-19 , Waste Management , Humans , Industrial Waste , Pandemics , Pyrolysis , SARS-CoV-2
4.
Energy Policy ; 154: 112322, 2021 Jul.
Article in English | MEDLINE | ID: covidwho-1237689

ABSTRACT

Being declared a global emergency, the COVID-19 pandemic has taken many lives, threatened livelihoods and businesses around the world. The energy industry, in particular, has experienced tremendous pressure resulting from the pandemic. In response to such a challenge, the development of sustainable resources and renewable energy infrastructure has demonstrated its potential as a promising and effective strategy. To sufficiently address the effect of COVID-19 on renewable energy development strategies, short-term policy priorities should be identified, while mid-term and long-term action plans should be formulated in achieving the well-defined renewable energy targets and progress towards a more sustainable energy future. In this review, opportunities, challenges, and significant impacts of the COVID-19 pandemic on current and future sustainable energy strategies were analyzed in detail; while drawing from experiences in identifying reasonable behaviors, orientating appropriate actions, and policy implications on the sustainable energy trajectory were also mentioned. Indeed, the question is that whether the COVID-19 pandemic will kill us or provide us with a precious lesson on future sustainable energy development.

5.
J Hazard Mater ; 416: 125856, 2021 08 15.
Article in English | MEDLINE | ID: covidwho-1193388

ABSTRACT

Inhalation of aerosols such as pharmaceutical aerosols or virus aerosol uptake is of great concern to the human population. To elucidate the underlying aerosol dynamics, the deposition fractions (DFs) of aerosols in healthy and asthmatic human airways of generations 13-15 are predicted. The Navier-stokes equations governing the gaseous phase and the discrete phase model for particles' motion are solved using numerical methods. The main forces responsible for deposition are inertial impaction forces and complex secondary flow velocities. The curvatures and sinusoidal folds in the asthmatic geometry lead to the formation of complex secondary flows and hence higher DFs. The intensities of complex secondary flows are strongest at the generations affected by asthma. The DF in the healthy airways is 0%, and it ranges from 1.69% to 52.93% in the asthmatic ones. From this study, the effects of the pharmaceutical aerosol particle diameters in the treatment of asthma patients can be established, which is conducive to inhibiting the inflammation of asthma airways. Furthermore, with the recent development of COVID-19 which causes pneumonia, the predicted physics and effective simulation methods of bioaerosols delivery to asthma patients are vital to prevent the exacerbation of the chronic ailment and the epidemic.


Subject(s)
Asthma , COVID-19 , Aerosols , Asthma/drug therapy , Computer Simulation , Humans , Lung , Models, Biological , Particle Size , SARS-CoV-2
6.
Environ Res ; 197: 111096, 2021 06.
Article in English | MEDLINE | ID: covidwho-1163738

ABSTRACT

This study is motivated by the amplified transmission rates of the SAR-CoV-2 virus in areas with high concentrations of fine particulates (PM2.5) as reported in northern Italy and Mexico. To develop a deeper understanding of the contribution of PM2.5 in the propagation of the SAR-CoV-2 virus in the population, the deposition patterns and efficiencies (DEs) of PM2.5 laced with the virus in healthy and asthmatic airways are studied. Physiologically correct 3-D models for generations 10-12 of the human airways are applied to carry out a numerical analysis of two-phase flow for full breathing cycles. Two concentrations of PM2.5 are applied for the simulation, i.e., 30 µg⋅m-3 and 80 µg⋅m-3 for three breathing statuses, i.e., rest, light exercise, and moderate activity. All the PM2.5 injected into the control volume is assumed to be 100% contaminated with the SAR-CoV-2 virus. Skewed air-flow phenomena at the bifurcations are proportional to the Reynolds number at the inlet, and their intensity in the asthmatic airway exceeded that of the healthy one. Upon exhalation, two peak air-flow vectors from daughter branches combine to form one big vector in the parent generation. Asthmatic airway models has higher deposition efficiencies (DEs) for contaminated PM2.5 as compared to the healthy one. Higher DEs arise in the asthmatic airway model due to complex secondary flows which increase the impaction of contaminated PM2.5 on airways' walls.


Subject(s)
Asthma , Lung , Computer Simulation , Humans , Italy , Mexico , Models, Biological , Particulate Matter/toxicity
7.
Environ Res ; 197: 110975, 2021 06.
Article in English | MEDLINE | ID: covidwho-1118425

ABSTRACT

The deposition phenomenon of microparticle and SAR-CoV-2 laced bioaerosol in human airways is studied by Taguchi methods and response surface methodology (RSM). The data used herein is obtained from simulations of airflow dynamics and deposition fractions of drug particle aerosols in the downstream airways of asthma patients using computational fluid dynamics (CFD) and discrete particle motion (DPM). Three main parameters, including airflow rate, drug dose, and particle size, affecting aerosol deposition in the lungs of asthma patients are examined. The highest deposition fraction (DF) is obtained at the flow rate of 45 L min-1, the drug dose of 200 µg·puff-1, and the particle diameter of 5 µm. The optimized combination of levels for the three parameters for maximum drug deposition is performed via the Taguchi method. The importance of the influencing factors rank as particle size > drug dose > flow rate. RSM reveals that the combination of 30 L min-1, 5 µm, 200 µg·puff- has the highest deposition fraction. In part, this research also studied the deposition of bioaerosols contaminated with the SAR-CoV-2 virus, and their lowest DF is 1.15%. The low DF of bioaerosols reduces the probability of the SAR-CoV-2 virus transmission.


Subject(s)
Hydrodynamics , Lung , Administration, Inhalation , Aerosols , Computer Simulation , Humans , Models, Biological , Particle Size
8.
Chemosphere ; 275: 130092, 2021 Jul.
Article in English | MEDLINE | ID: covidwho-1095908

ABSTRACT

COVID-19 has led to the enormous rise of medical wastes throughout the world, and these have mainly been generated from hospitals, clinics, and other healthcare establishments. This creates an additional challenge in medical waste management, particularly in developing countries. Improper managing of medical waste may have serious public health issues and a significant impact on the environment. There are currently three disinfection technologies, namely incineration, chemical and physical processes, that are available to treat COVID-19 medical waste (CMW). This study focuses on thermochemical process, particularly pyrolysis process to treat the medical waste. Pyrolysis is a process that utilizes the thermal instability of organic components in medical waste to convert them into valuable products. Besides, the technique is environmentally friendly, more efficient and cost-effective, requires less landfill capacity, and causes lower pollution. The current pandemic situation generates a large amount of plastic medical wastes, which mainly consists of polyethylene, polypropylene, polystyrene, polyethylene terephthalate, and nylon. These plastic wastes can be converted into valuable energy products like oil, gas and char through pyrolysis process. This review provides detailed information about CMW handling, treatment, valuable product generation, and proper discharge into the open environment.


Subject(s)
COVID-19 , Medical Waste , Humans , Incineration , Pyrolysis , SARS-CoV-2
9.
Aerosol and Air Quality Research ; 20(6):1172-1196, 2020.
Article | WHO COVID | ID: covidwho-601230

ABSTRACT

Determining the hotspots and deposition efficiencies (DEs) for aerosols in human airways is important for both research and medical purposes. The complexity of the human airways and the breathing process limit the application of in vitro measurements to only two consecutive branches of the human airway. Herein, in-depth information on in vitro experiments and state-of-the-art review on various computational fluid dynamics (CFD) applications and finite element methods on airflow and aerosol motion in both healthy and obstructed human airways are provided. A brief introduction of the application of one-dimensional and two-dimensional mathematical models to investigate airflow and particle motion in the lungs are further discussed. As evident in this review, aerosol deposition in the upper and central human airway regions has been extensively studied under different inhalation statuses and conditions such as humidity as well as different aerosol sizes, shapes, and properties. However, there is little literature on the lower sections of the human airways. Herein, a detailed review of the fundamentals for both in vitro experiments and numerical simulation at different sections of human airways is done. Exceptional features and essential developments in numerical methods for aerosol motion in healthy and diseased human airways are also discussed. Challenges and limitations associated with the applications of in vitro experiments and CFD methods on both human-specific and idealized models are highlighted. The possibility of airborne transmission pathways for COVID-19 has been discussed. Overall, this review provides the most useful approach for carrying out two-phase flow investigations at different sections of the human lungs and under different inhalation statuses. Additionally, new research gaps that have developed recently on the role of bioaerosols motion in COVID-19 transmission, as well as the deposition of aerosols in impaired human airways due to coronavirus (COVID-19) are underlined.

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