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Number of results: 13
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Abstract

Here One important aspect of the process of anaerobic stabilisation of sewage sludge in medium and large sewage treatment plants, in addition to sludge mineralisation, is the acquisition of a valuable source of energy, which is biogas. There are well-known methods of intensifying the process of methane fermentation by subjecting sludge to disintegration using physical factors, i.e. ultrasonic field. Acetate production is the ratelimiting step in the acetate consumption pathway and affects the efficiency of the anaerobic stabilisation process. The product of the first stage of the process is also the substrate for the next stage. Therefore, it is advisable to subject sewage sludge to disintegration, which increases its susceptibility to biodegradation. Sludge modification with the above-mentioned method causes a significant increase in the concentration of organic substances in the supernatant liquid. The reflection of the physical and chemical transformations of sludge in the disintegration processes is the change in their structure expressed by the increase in the degree of particle dispersion. The disintegration of sludge using sonolysis is an effective process solution, both in terms of technology and energy, in terms of obtaining biogas, which is a valuable source of energy.
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Authors and Affiliations

Iwona Zawieja
1
ORCID: ORCID

  1. Faculty of Infrastructure and Environment, Czestochowa University of Technology,Dąbrowskiego 73, 42-201, Czestochowa, Poland, ORCID 0000-0002-4480-8736
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Abstract

The two aims of this study were to obtain stable thyme-oil loaded nanoemulsions using the statistical design of experiment method (DOE) and to confirm their antimicrobial and disinfecting properties. Thyme oil was used as the oil phase, ECO Tween ® 80 acted as an emulsifier, and the rest of the formulation was deionized water. Ultrasonication was chosen as the method of obtaining the nanoemulsions. It was checked whether the input parameters (oil concentration, emulsifier concentration, amplitude, and sonication time) had a significant impact on the output parameters (nanoemulsion particle size, polydispersity index, viscosity, and stability over time). For the formulations selected on the basis of the statistical data analysis, the values of minimum inhibitory concentrations (MIC) and minimum biocidal concentrations (MBC/MFC) were determined in relation to 10 bacterial strains and 10 strains fungi (filamentous fungi, yeast-like fungi). The results obtained from the statistical analysis showed that the optimal concentration of the thyme oil in nanoemulsion should amount up to 2%. Biological studies proved that the obtained formulation had stronger antibacterial and antifungal activity compared to pure oil. Moreover, it was shown that the nanoemulsion caused the required for disinfectants reduction of > 5 log of bacterial strains ( S. aureus, P. aeruginosa) and > 4 log of fungal strains ( C. albicans) after 30 minutes.
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Authors and Affiliations

Małgorzata Miastkowska
1
ORCID: ORCID
Anna Łętocha
1
Alicja Michalczyk
2
ORCID: ORCID

  1. Department of Chemical Engineering and Technology, Cracow University of Technology,Cracow, Poland
  2. Lukasiewicz - Research Network-Institute of Industrial Organic Chemistry, Warsaw, Poland
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Abstract

Life Cycle Assessment (LCA) is an important tool of Circular Economy (CE), which performs the analysis in a closed loop (“cradle-to-cradle”) of any product, process or technology. LCA assesses the environmental threats (climate change, ozone layer depletion, eutrophication, biodiversity loss, etc.), searches for solutions to minimize environmental burdens and together with CE contributes to reducing greenhouse gas emission, counteracts global climate crisis. The CE is a strategy for creating value for the economy, society and business while minimizing resource use and environmental impacts through reducing, re-using and recycling. In contrast, life cycle assessment is a robust and science-based tool to measure the environmental impacts of products, services and business models. Combining both the robustness of the LCA methodology and the principles of circular economy one will get a holistic approach for innovation. After a presentation of the LCA framework and methods used, 27 examples of case studies of comparative LCA analysis for replacement materials to reduce environmental load and their challenges as assessment methods for CE strategies are presented. It was concluded that there is a need for improvement of existing solutions, developing the intersection between the CE and LCA. Suggestions for developing a sustainable future were also made.
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Authors and Affiliations

Stanisław Ledakowicz
1
ORCID: ORCID
Aleksandra Ziemińska-Stolarska
1
ORCID: ORCID

  1. Faculty of Process and Environmental Engineering, Lodz University of Technology, 213 Wólczańska Street, 90-924 Lodz, Poland
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Abstract

This work presents results of investigations on biotrickling filtration of air polluted with cyclohexane co-treated in binary, ternary and quaternary volatile organic compounds (VOCs) mixtures, including vapors of hexane, toluene and ethanol. The removal of cyclohexane from a gas mixture depends on the physicochemical properties of the co-treated VOCs and the lower the hydrophobicity of the VOC, the higher the removal efficiency of cyclohexane. In this work, the performance of biotrickling filters treating VOCs mixtures is discussed based on surface tension of trickling liquid for the first time. A mixed natural – synthetic packing for biotrickling filters was utilized, showing promising performance and limited maintenance requirements. Maximum elimination capacity of about 95 g/(m 3·h) of cyclohexane was reached for the total VOCs inlet loading of about 450 g/(m 3·h). This work presents also a novel approach of combining biological air treatment with management of a spent trickling liquid in the perspective of circular economy assumptions. The waste liquid phase was applied to the plant cultivation, showing a potential for e.g. enhanced production of energetic biomass or polluted soil phytoremediation.
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Authors and Affiliations

Piotr Rybarczyk
1
ORCID: ORCID
Bartosz Szulczyński
1
ORCID: ORCID
Dominik Dobrzyniewski
1
ORCID: ORCID
Karolina Kucharska
1
ORCID: ORCID
Jacek Gębicki
1
ORCID: ORCID

  1. Gdańsk University of Technology, Faculty of Chemistry, Department of Process Engineering and Chemical Technology, 80-233 Gdańsk, Narutowicza 11/12, Poland
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Abstract

Chemical and process engineering offers scientific tools for solving problems in the biomedical field, including drug delivery systems. This paper presents examples of analyzing the dynamics of dispersed systems (aerosols) in medical inhalers to establish a better relationship between the test evaluation results of these devices and the actual delivery of drugs to the lungs. This relationship is referred to as in vitro-in vivo correlation (IVIVC). It has been shown that in dry powder inhalers (DPls), the aerosolization process and drug release times are determined by the inhalation profile produced by the patient. It has also been shown that inspiratory flow affects the size distribution of aerosols generated in other inhalation devices (vibrating mesh nebulizers, VMNs), which is due to the evaporation of droplets after the aerosol is mixed witha dditional air taken in by the patient. The effects demonstrated in this work are overlooked in standard inhaler testing methods, leading to inaccurate information about the health benefits of aerosol therapy, thus limiting the development of improved drug delivery systems.
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Authors and Affiliations

Agata Dorosz
1
ORCID: ORCID
Arkadiusz Moskal
1
ORCID: ORCID
Tomasz R. Sosnowski
1
ORCID: ORCID

  1. Warsaw University of Technology, Faculty of Chemical and Process Engineering, Waryńskiego 1, 00-645 Warsaw, Poland
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Abstract

The paper discusses the application possibilities of ceramic foam in a thermal combustion process of a lean methane-air mixture. The experiments were done in a ceramic foam bed. The foam (Vukopor ® A) was made mainly of Al 2O 3. The foam samples were packed in a tubular reactor symmetrically placed in a laboratory furnace. It was assumed that the tested foam should have a surface close to the monolith surface area which was tested in a previous work (Pawlaczyk and Gosiewski, 2015). Pore density of the tested foam was 10 PPI. The tested air mixture contained 0.51 - 0.76 vol. % of methane. The results show that thermal methane oxidation in foam is possible in the acceptable range of temperatures. The combustion process in foam is characterized by similar ignition temperature to tests carried out in monolith, a more intense course, and better methane conversion at lower temperatures.
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Authors and Affiliations

Anna Pawlaczyk-Kurek
1
ORCID: ORCID
Aleksandra Janusz-Cygan
1
ORCID: ORCID

  1. Polish Academy of Sciences, Institute of Chemical Engineering, Baltycka 5, 44-100 Gliwice, Poland
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Abstract

In the presented work, the conditions of the high-temperature and mechanochemical method for the synthesis of compound Sm 5VO 10 and their influence on its physicochemical properties were studied. The following methods were used for the study: X-ray powder diffraction (XRD), differential thermal analysis (DTA), infrared spectroscopy (FTIR), ultraviolet and visible light spectroscopy (UV–VIS–DRS), scanning electron microscopy (SEM-EDX), and laser beam diffraction spectrometry (LDS). Based on the results, it was determined that the compound Sm 5VO 10 is thermally stable in air atmospheres up to 1475 °C, crystallises in a monoclinic system, and its structure is made up of oxygen VO 4 and SmO 8 polyhedra. The estimated energy gap value for nanometric, mechanochemically obtained Sm 5VO 10 was about 3.20 eV, and for the microcrystalline, obtained with the high-temperature method, was about 2.75 eV. The established physicochemical characterisation of Sm 5VO 10 initially showed that the compound could find potential applications, e.g. as a photocatalyst for water purification or as a component of new optoelectronic materials.
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Authors and Affiliations

Kamil Kwiatkowski
1
ORCID: ORCID
Mateusz Piz
1
ORCID: ORCID
Elżbieta Filipek
1
ORCID: ORCID

  1. West Pomeranian University of Technology in Szczecin, Faculty of Chemical Technology and Engineering, Piastów 42, 71-065 Szczecin, Poland
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Abstract

Simplified optimization method using the MATLAB function fminbnd was adopted to determine the optimal feed temperature (OFT) for an isothermal packed-bed reactor (PBR) performing hydrogen peroxide decomposition (HPD) by immobilized Terminox Ultra catalase (TUC). The feed temperature was determined to maximize (minimize) the average reactant conversion (reactant concentration) over a fixed period time at the reactor outlet. The optimization was based on material balance and rate equation for enzyme action and decay and considered the effect of mass-transfer limitations on the system behavior. In order to highlight the relevance and applicability of the work reported here, the case of optimality under isothermal operating conditions is considered and the practical example is worked out. Optimisation method under consideration shows that inappropriate selection of the feed temperature may lead to a decrease in the bioreactor productivity.
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Authors and Affiliations

Ireneusz Grubecki
1
ORCID: ORCID
Wirginia Tomczak
2
ORCID: ORCID

  1. Cracow University of Technology, Faculty of Chemical Engineering and Technology, Warszawska 24, 31-155 Cracow, Poland
  2. Bydgoszcz University of Science and Technology, Seminaryjna 3, 85-326 Bydgoszcz, Poland
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Abstract

Cosmetic emulsion bases containing extracts from natural plants were produced. The emulsifier was an aqueous solution of self-emulsifying base made from apricot kernel oil and soy lecithin, while the oil phase was based on coconut, almond or grape seed oils. In addition, mixtures enriched with vegetable glycerine were produced. It was found that for the emulsions with almond oil as the concentration of the oil phase increased, the value of the average Sauter diameter increased. In comparison, results for emulsions with coconut oil and emulsions with grapeseed oil did not give such a clear relationship. It was also shown that for stable emulsions, the self-emulsifying base of apricot kernel oil performed much better than soy lecithin. The addition of vegetable glycerine to the mixture resulted in a reduction of the average droplet diameter. Produced emulsions were also visually observed for 60 days to assess their stability and possible aging processes. In order to exclude the formation of microorganisms, periodic density control and microscopic examinations were carried out. The presence of microorganisms 30 in the analysed emulsion was evaluated using microscopic and culture techniques. No tarnish waso bserved on the surface of the samples, indicating the formation of mould, which can lead to poisoning and the development of allergies, respiratory diseases, liver diseases, ulcers, or bleeding in the intestines.
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Authors and Affiliations

Waldemar Szaferski
1
ORCID: ORCID
Piotr T. Mitkowski
1
ORCID: ORCID
Marcin Janczarek
1
ORCID: ORCID

  1. Poznan University of Technology, Institute of Chemical Technology and Engineering, Berdychowo 4, 60-965 Poznan, Poland
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Abstract

In recent years, European countries have experienced a noteworthy surge in the interest surrounding renewable energy sources, particularly the integration of photovoltaic (PV) panels with various types of heat pumps. This study aims to evaluate the energy performance of a grid19 connected hybrid installation, combining a PV array with an air-source heat pump (AHP), for domestic hot water preparation in a residential building located in Cracow, Poland. The primary focus of this evaluation is to assess the extent to which self-consumption (SC) of energy can be increased. The study utilizes Transient System Simulation Tool 18 software to construct and simulate various system models under different scenarios. These scenarios include building electricity consumption profiles, PV power systems, and the specified management of AHP. Analyses were conducted over a period of 1 year to assess the operational performance of the systems. In the considered installations, the differences in SC values between PV installation ranged from 9 to 25%. Notably, the highest SC values were observed during the winter months. AHP with operation control allows to obtain in some months of the year up to 35% higher value the SC parameter compared to systems without AHP. The highest annual 29 SC value recorded reached 83.9%. These findings highlight the crucial role of selecting an appropriate PV system size to maximize the SC parameter.
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Authors and Affiliations

Sebastian Pater
1
ORCID: ORCID

  1. Cracow University of Technology, Faculty of Chemical Engineering and Technology, Warszawska 24, 31-155 Cracow, Poland
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Abstract

The work motivation was to investigate in vitro system simulating drug release from Drug Eluting Stent (DES). The experiments were conducted in a custom designed unit simulating drug release from polymer covering DES in a simplified way. The active substance diffuses from a thin, internal annular layer of hydrogel (imitating “stent”) to the outer cylindrical layer of hydrogel (“artery wall”) and is at once drifted away by coaxially flowing solution (“blood”). The conducted research proved functionality of the experimental unit. The rate of mass transfer depends considerably on the mass driving force and on the affinity of substance-hydrogel. The volumetric flow rate and liquid viscosity did not affect the process significantly. The effective diffusion coefficient was calculated as a process parameter and then used in the other variants. Diffusion in hydrogel is the mechanism limiting the mass transfer in the examined system. For the first attempt, the diffusive model used in literature was employed. The provided calculations are consistent with experimental data and therefore show that despite its simplifications the model allows to estimate the amount of released substance.
In conclusion, the relative substance mass, changing over time, was estimated in the respective parts of the unit. The prospect of determining the relative mass of the substance appearing in the subsequent parts of the system over time provides the opportunity to adjust the respective process parameters, which will facilitate control over the rate of mass release.
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Authors and Affiliations

Anna Adach-Maciejewska
1
ORCID: ORCID
Klaudia Kopka
1

  1. Warsaw University of Technology, Faculty of Chemical and Process Engineering, Waryńskiego 1, 00-645 Warsaw, Poland
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Abstract

The influence of a fixed adsorption bed height on the adsorption process was studied using acetone, ethyl acetate, toluene, and n-butyl acetate as a gaseous adsorbate mixture. All experiments were conducted under the same gas flow and temperature conditions. Concentrations of adsorbates were monitored using gas chromatography with a flame ionization detector. Activated carbon WG-12 (Grand Activated Sp. z o.o) was selected as the adsorbent, and the following heights of the fixed adsorption bed were used: 0.8, 1.6, 3.2, and 4.8 cm. The results of the study allowed to deduce that as the height of the fixed adsorption bed increased, the degree of displacement of adsorbate molecules from the bed strengthened. In addition, it was found that both the bed breakthrough time increased linearly with a height rise of the fixed adsorption bed. The process carried out on a fixed adsorption bed with a height of 0.8 cm was characterized by an undeveloped mass transfer zone, as well as the complete displacement of the most volatile components (acetone and ethyl acetate). The utilization rate of the fixed adsorption bed also increased as the height of the adsorption bed went up. However, at a certain bed height, the bed breakthrough curves were formed and the adsorption capacity did not change significantly, solely the bed breakthrough time increased.
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Authors and Affiliations

Martyna Jurkiewicz
1
ORCID: ORCID
Marlena Musik
1
ORCID: ORCID
Robert Pełech
1
ORCID: ORCID

  1. West Pomeranian University of Technology in Szczecin, Faculty of Chemical Technology and Engineering, Department of Chemical Organic Technology and Polymeric Materials, Pułaskiego 10, 70-322 Szczecin, Poland
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Abstract

The paper aims to show a search method for optimal conditions of 3A, 13X, ZSM-5 zeolite thermal regeneration after adsorption from a liquid water-isopropanol mixture. Comparative TGA-DTG results for heating of wet zeolites with different structure and hydrophobicity showed characteristic effects corresponding to the optimal temperature of zeolite regeneration. The consequences of overheating and collapse of the 3A, 13X, ZSM-5 zeolite structure at temperatures of 850, 900, 1000 °C, respectively, were recorded with XRD method. Moreover, XRD and NIR/DRS tests of loaded and regenerated zeolite samples showed interaction of adsorbate and co-adsorbed water with adsorbent and revealed influence of adsorption and regeneration processes on the adsorbent structure. Investigations of the regeneration of the zeolite 3A bed after adsorption of water from the isopropanol solution in the temperature swing adsorption (TSA) process were carried out by heating the bed with inert gas at 250 °C and different purge gas streams in the range of 1.68–2.40 kg/h. Four stages of wet bed regeneration were distinguished, which corresponded to the effect observed during TGA-DTG tests. For each stage, the specific demand for purge gas and energy was determined depending on the gas stream and its minimum value of 2.16 kg/h was indicated.
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Authors and Affiliations

Piotr Tabero
1
ORCID: ORCID
Elżbieta Gabruś
2

  1. West Pomeranian University of Technology in Szczecin, Faculty of Chemical Technologyand Engineering, Department of Inorganic and Analytical Chemistry, Piastów 42, 71-065 Szczecin, Poland
  2. West Pomeranian University of Technology in Szczecin, Faculty of Chemical Technology and Engineering, Department of Chemicaland Process Engineering, Piastów 42, 71-065 Szczecin, Poland

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