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EN
Atmospheric water harvesting (AWH) devices represent a fruitful hope to cope with the water shortage problem throughout the world. The vast development in AWH technology and the wide spread of various AWH techniques will largely contribute to the implementation of AWH machines in different household, agricultural and industrial applications. In the last decades, a huge amount of research has been done on AWH methods with amazing differences in results that mislead readers and even researchers. In this study, the AWH theoretical technology developments, various AWH methods and various AWH machines in the market were reviewed. A comparison between the different theoretical methods was presented, concentration on unifying results based on area and energy consumption per harvested amount was performed for clear judgment on the different published data. The gaps between theory and market available devices were stated with recommendations for further development in AWH technology.
EN
Hot storage tanks (HST) are known for their high energy consumption, attributed to variations in usage, heat dissipation within the tank, and heat losses to the surroundings. This study proposes a chimney-type electrically heated HST, which is investigated under static mode to enhance its thermal performance. Different natural circulation areas (chimney areas) with large (9.5 cm diameter), medium (2.5 cm diameter), and small (1.5 cm diameter) sizes were utilized to examine the effect of natural circulation on the HST performance. Additionally, the influence of chimney insulation on the HST performance was also studied. The experiments revealed that the chimney significantly affected the thermal stratification within the tank. Different chimney contact diameters (9.5 cm, 2.5 cm, and 1.5 cm) were tested, showing varying degrees of thermal stratification. The results indicated that smaller chimney contact diameters led to higher thermal stratification and more rapid heating of the top layer temperatures. However, the impact of insulation on thermal performance was inconclusive, suggesting the need for more effective insulation and further investigation into the dynamic mode of operation. The findings also highlighted the faster heating of the top outer layer compared to the larger diameter, emphasizing the significance of the chimney type electrical heater in the hot storage tank.
EN
The industrial development and economic growth have provided a conducive environment for manufacturing process improvements. However, this progress also poses several challenges to remain competitive and improve efficiency and productivity. Failure mode and effect analysis is a systematic approach that is used extensively in the field of risk management to enhance quality and efficiency in different sectors including manufacturing and healthcare sectors. In this paper, novel approach to enhance the failure mode and effects analysis is proposed. The approach can address the inherent uncertainty involved in assigning numerical values to represent the severity, occurrence and detection of each failure. A case study from a small-scale factor was assessed to ensure the applicability and effectiveness of the proposed approach.
EN
Nowadays, sulfur is considered one of the primary resources of the chemical industry, most of which is produced as a refinery by-product during the processing of oil and natural gas. Sulfur production volumes are increasing every year, while the demand for it does not always match the growing supply, which leads to a serious problem of sulfur surplus in the world market. Granulated sulfur – the main commercial type of elemental sulfur – is transported in large quantities both by land and sea and can have a negative impact on the environment. At the moment, the issue of the negative impact of granulated sulfur on the environment has not been fully studied, which determines the relevance of this research. This review article presents the global market of granulated sulfur, paying attention to its safe transport – from the producer to the consumer. The potentially harmful factors of the impact of sulfur handling on elements of the natural environment, such as atmospheric air, water reservoirs, soil and vegetation, were also taken into account.
EN
The worldwide transition to a future with net-zero emissions depends heavily on solar energy. However, when land prices rise, and population density rises, the need for large land expanses to develop solar farms poses difficulties. Floating Photovoltaics (FPV) has come to light as a viable remedy to this problem. FPV, which includes mounting solar panels on bodies of water, is gaining popularity as a practical choice in many nations worldwide. A significant capacity of 404 GWp for producing clean energy might be attained by using FPV to cover only 1% of the world’s reservoirs. This review shows that FPV has several benefits over conventional ground-mounted PV systems. On the other hand, there is a large study void regarding the effects of FPV on water quality and aquatic ecosystems. This review looks at the most recent FPV research, including its advantages, disadvantages, and potential. It looks into the compatibility of various bodies of water, worldwide potential, system effectiveness, and the possibility of integrating different technologies with FPV.
EN
Many particle accelerators rely on maintaining low pressures to ensure efficient operation, minimize beam losses, and reduce radiation background. To ensure a beam lifetime of 1–20 hours for the Synchrotron-light for Experimental Science and Applications in the Middle East (SESAME) vacuum system, an ideal average dynamic pressure of 1×10-9 mbar was targeted. This pressure was intended to be maintained while running the accelerator at a current of 400 mA after a cumulative dose of 100 Ah. In this study, a MATLAB code was employed to develop a series of one-dimensional equations that simulate the behavior of the vacuum system within the SESAME storage ring. The proposed model was then compared with the results generated by the VACCALC software and the Particle Monte Carlo (TPMC) MOLFLOW code, establishing a comprehensive assessment framework. The collected data from the model was subsequently compared with the recorded static and dynamic pressure measurements obtained during more than 1000 Ah of beam conditioning at 2.5 GeV. In results, the projected and actual values of dynamic pressures exhibited a satisfactory degree of agreement across the investigated range of beam conditioning doses, with a consistency factor exceeding 2 after a 100 Ah dose.
EN
The objective of this study is to compare the performance of diesel engines, fuelled with biofuel blends extracted from corn, sunflower, and palm oils, against pure diesel. The experiments were performed using Lister LVI, single-cylinder, direct injection, four-stroke engines, with a compression ratio of 17:1. The following parameters were analysed: brake torque, brake mean effective pressure (BMEP), brake specific fuel consumption (BSFC), brake thermal efficiency (BTE), and exhaust gas temperature (EGT). The findings indicate that the characteristics of biodiesels are close to diesel fuel. Therefore, biodiesel becomes a viable alternative to diesel fuel without any modifications. Pure diesel has higher brake thermal efficiency and lower BSFC than all the biodiesel blends tested in this study. In addition, the engine consumes less fuel for biodiesel blends than pure diesel. High exhaust temperatures are conducive to nitrogen oxides (NOx) generation; hence, this study reveals that the exhaust temperature is reduced when utilizing biodiesel compared to pure diesel. According to several tests, palm biodiesel provides greater torque and BMEP than the rest of the biodiesel blends, and pure diesel due to emitting less NOx. Therefore, it stands to reason that it would be utilized in a diesel engine.
EN
The aim of this study was to improve the residential photovoltaic systems (RPVS) sector, using surveys as the research method. The research was carried out in four selected districts in Jordan, taking into account the largest population. The prepared sets of questionnaires covered a wide range of topics, divided into three parts and seven sections. The results showed that the highest use of solar energy for heating was in the Amman district, while in the Irbid and Zarqa districts photovoltaic (PV) system installations can potentially be more prospective because of high electricity and thermal energy usage. This study found the willingness of people to have a combined on-grid/off-grid PV systems, made by European and American manufacturers. However, those respondents were afraid of the high maintenance cost, the unclear lifespan of the system, doubtful reliability, and unclear warrantee of the PV systems.
EN
In this paper, an simulated investigations for the modified lithium-ion battery thermal management system using PID, as well Null-Space-based Behavioral (NSB) controllers were presented. This work sought to keep the battery life at its optimum temperature using low power. We used thermoelectric modules with collaborating controllers to minimize the electricity consumed during the cooling process. Comparing to PID, NSB controller achieved the reduction of consumed power of 20%, faster temperature return to the set point, and a more uniform controlling the temperature of the battery cells.
PL
W niniejszym artykule przedstawiono wyniki symulacyjnych badań nad zmodyfikowaniem systemu zarządzania temperaturą akumulatora litowo-jonowego z wykorzystaniem regulatora PID oraz regulatora behawioralnego typu Null-Space (NSB). Celem pracy było utrzymanie żywotności baterii w optymalnej temperaturze przy niskim poborze mocy. Wykorzystano moduły termoelektryczne z dedykowanym sterownikiem dla zmniejszenia zużycia energii elektrycznej podczas procesu chłodzenia. W porównaniu do PID, zastosowanie regulatora NSB umożliwia redukcję pobieranej mocy o 20%, szybszy powrót temperatury do wartości zadanej oraz bardziej równomierne sterowanie temperaturą ogniw akumulatora
EN
The purpose of the study was to assess the impact of industrial wastewater on the concentration of methanol in the considered section of the Ob River basin, present proposals for the implementation of a new treatment system and analyse the implementation results. On the basis of the results of the analysis of the known methods for reducing the concentration of methanol in water, a new technological scheme for post-treatment of effluents using biological treatment with methylotrophic Methylomonas methanica Dg bacteria was proposed. The calculation of the dilution of treated wastewater using the “NDS Ecolog” program was carried out on the basis of the detailed calculation method of Karaushev, the results of which showed a decrease in the concentration of methanol in the control section to 0.0954 mg∙dm-3 (permissible concentration is 0.1 mg∙dm-3). During the period of the flood of the Glukhaya channel, it ceases to be a separate water body and, in fact, becomes part of the flood channel of the Ob River. Certain parts of the flooded areas, due to elevation changes, communicate with the channel only during a short period of time when the water level rises, i.e. 3-5 weeks during the flood period, and in fact remain isolated reservoirs for the rest of the time, potentially acting as zones of accumulation and concentration of pollutants.
EN
The results of X-ray diffraction, thermogravimetric and FTIR spectroscopy analyses of mineral composition indicated that the El-Lajjun oil shale is principally composed of calcite, quartz with minor amounts of kaolinite), gypsum, and apatite. The obtained oil shale ash products at 830 °C and 1030 °C are dominated by lime, quartz, anhydrite, portlandite, gehlenite, and amorphous phases. The TGA weight loss curves clearly indicate that it occurred in the temperature range from 310 to 650 °C. The decomposition of oil shale carbonates was detected above 750°C. The functional groups in the organic material of oil shale are dominated by the aliphatic hydrocarbons, the semi-ash of which had diverse structures of polycyclic aromatic hydrocarbons. The most intensive of combustion occurred in the temperature range of 400–750 °C. In this temperature range, about 75 wt.% was accounted for the total mass loss.
EN
This research proposed an integrated eco-system for conditioning an outdoor public area (park or sport) in a hothumid environment. It is accomplished by the use of a dehumidifier control machine driven by renewable solar power; after which air is distributed throughout a ducting system. The system will harvest moisture from the air, utilize it for drinking water production and plants irrigation as well as deliver low temperature, low humidity ratio air for controlling the outdoor air, which results in a comfortable outdoor relative humidity and temperature (24 °C, 50% RH). The Integrated Eco-Friendly Cooling System (IEFCS) is a sustainable self-dependent in energy and water sources. It provides a positive impact on the microclimate of the site, assists in night illumination, supplies water for drinking, plant irrigation, and allows people to enjoy a thermally comfortable atmosphere. The advantages include low maintaining cost as well as the possibility to be scaled and implemented anywhere according to the selected location.
EN
Low-temperature heat sources have become increasingly popular in recent years, particularly for energy generation. The majority of thermal devices in the market (including devices using solar energy, geothermal energy, waste energy, and so on) transform heat into electricity indirectly, requiring mechanical work before producing power. Through the Seebeck effect, the technology that employs a thermoelectric generator (TEG) may directly transform heat energy into electricity. The TEG technology provides several advantages, including compactness, quietness, and the absence of moving components. TEGs have a low thermal and electrical efficiency, which is one of their main drawbacks. Therefore, the performance of a thermoelectric generator is improved by employing liquid evaporation heat transfer in this manuscript. The performance of the thermoelectric was examined experimentally and compared to the liquid evaporation mode under varied heat flux values and different modes of heat transfer in terms of free and forced convection with and without fins. The experimental results revealed that when compared to free convection without fins, adopting forced liquid evaporation convection would improve TEG voltage variation by 435.9%.
EN
Recently, hydropower energy resources become an attractive means of generating electricity for, off-grid networks, especially in rural areas. This work aims to design a suitable prototype of an energy-storing system, which is called a Potential Steam Hydro Capacitor. This system gives a manageable source of electricity, and partially provides drinkable water, at a low cost, as an alternative to comparatively high-cost electrical batteries. The system is composed of two solar collectors, connected in series. The working fluid in the first collector is Dead Sea water, and in the second fresh water, a heat exchanger, a thermosiphon solar water heater connected to a high column to pass the vapor to high altitude, and a condensation unit on the roof of the building. The system succeeds in producing a considerable amount of fresh water at a height of 3.4 m. The potential energy produced, can operate a small turbine. The capability of the system, to convert thermal energy in the freshwater, to potential energy, was high, with an efficiency of 66.7%. adding solar concentrators to the system would increase the water collected.
EN
This review presents the usage of adhesives and binders for agglomeration of particle materials, including waste, in order to obtain strong bodies. The binding materials were classified into three categories: inorganic binders, organic binders, and compound binders. Many examples of the agglomeration effect of binders in view of their adhesive and thickening reveal that they have a significant impact on the qualities and use of waste lumps. Binders for fine waste granulation, briquetting, and pelletizing were demonstrated in-depth. In all cases, the mechanical strength of the agglomerates produced was increased. It was observed that the majority of the additives may be easily obtained from waste resources, posing a minimal environmental risk.
EN
Particulate materials and waste from industrial processes are troublesome in storage, transport and utilization, mainly due to their large volume and dusting. Therefore, originally the main reason for developing the agglomeration processes was to eliminate the afore-mentioned disadvantages. However, the modifications introduced to the merging processes of materials enabled obtaining a new type of products widely used in various applications. For the agglomeration of the inorganic materials, often containing hazardous substances, the disposal and transformation technologies are available for the safe products that can be used, for example, in civil engineering and construction. In turn, the agglomeration of the materials containing organic substances or fine coal, producing alternative fuels for energy recovery. Obviously, the combustion of these fuels results in a subsequent generation of waste in the form of bottom and fly ash, but they can be successfully further agglomerated to produce more valuable products. The numerous examples of the use of various agglomeration techniques to complete utilization of fine grains was shown. An additional effect of the agglomeration processes was also the fulfilment of the economy criteria, which matches with the principles of sustainable development of the environment. Supporting by worldwide literature, the selected agglomeration techniques were discussed, such as: solidification, granulation, extrusion, briquetting, as well as post-agglomeration high-temperature processing.
EN
This is a scoping review of agglomeration techniques to obtain of solid bodies from particle waste-materials for their utilization. For this purpose, the granulation and briquetting of fine coal and fly ash were presented in detail. Many successful works on solid fuels production, with coal only, and also with the addition of biomass, were presented. During the solid fuel combustion in power boilers, significant amounts of ash are generated. The properties of fly ashes were taken into consideration, and different methods of their utilization were proposed to obtain a wide range of useful products. Con-sequently, the waste resources of coal and ash were fully utilized. In final remarks, it was concluded, that the agglomeration techniques play an important role in waste management, but particularly in the circular economy.
PL
Przedstawiono sylwetkę profesora Jan Siuty, założyciela i długoletniego Redaktora Naczelnego czasopisma „Inżynieria Ekologiczna”. Zarysowano jego życiorys i dorobek, ale głównie skupiono się na jego pasji w propagowaniu inżynierii ekologicznej jako dziedziny wiedzy. Na tle jego licznych działań i osiągnięć, starano się pokazać jakim był człowiekiem i jak duży wpływ wywarł na wielu swoich uczniów i współpracowników. Był inspiratorem wielu pomysłów, bezinteresownym opiniodawcą, jednocześnie krytycznym i życzliwym, w pełni zaangażowany i niezwykle pracowity dla uzyskania założonych celów. Pozostawił wielu kontynuatorów swojego życiowego dorobku; dumnych, że mieli zaszczyt być jego przyjaciółmi.
EN
The profile of Professor Jan Siuta, the founder and long-time Editor-in-Chief of the “Inżynieria Ekologiczna” journal, was presented. His biography and legacy are outlined, but the main focus is on his passion for promoting ecological engineering as a field of knowledge. Against the background of his numerous activities and achievements, efforts were made to show what human he was and how much influence he had on many of his students and colleagues. He was the inspirer of many ideas, a disinterested opinion-maker, at the same time critical and favorably, fully committed, and extremely diligent in achieving the set goals. He left many followers of his life achievements; proud that they had the honor of being his friends.
EN
The research was intended to develop a biocomposite as an alternative biodegradable material, for the production of, e.g., disposable utensils. The author’s tested thermoplastic maize starch, both without additives and with the addition of crumbled flax fiber in the share of 10, 20 and 30 wt%. The plasticizer added was technical glycerin and the samples were produced by a single-screw extruder. The mechanical strength tests were performed, including the impact tensile test and three-point bending flexural test. Afterwards, the samples were tested for biodegradability under anaerobic conditions. The methane fermentation process was carried in a laboratory bioreactor under thermophilic conditions with constant mixing of the batch. All samples proved to be highly susceptible to biodegradation during the experiment, regardless of the flax fiber share. The biogas potential was about 600 ml·g-1, and the methane concentration in biogas ranged from 66.8 to 69.6%. It was found, that the biocomposites can be almost completely utilized in bioreactors during the biodegradation process. The energy recovery in the decomposition process with the generation of significant amount of methane constitutes an additional benefit.
EN
In this study, the adsorption behavior of natural and activated zeolites with respect to Cd2+, Cr3+, Pb2+and Zn2+, was studied in order to consider theirabilityto remove hazardousmetals fromdrilling mud. The batch method was employed, using initial metal concentrations in solution in the range of0.1 to 2.5 mg/dm3. It was determined that independently of the concentration, the adsorption ratios of zeolite towardsmetal cations match the Langmuir and Freundlich isotherms. The results of the research on the reduction of concentration of hazardousmetals from drilling mud wastewater by means of natural and activated zeoliteswere presented in the further part of this work. Natural and activated zeolites were introduced in portions (from 0.2to 10 g) to 100 cm3of wastewater; then, the content of metalions was determined using an inductively coupled plasma spectrometer. The experimental data showed that the applicationof activated zeolite enabled the removal rate of Cr3+, Pb2+, Zn2+and Cd2+close to 93%, 45%, 56% and 84%, respectively. In the case of the natural zeolite, the degree of hazardousmetals removal was lower by only a few percent, but still high enough to beinteresting from the practical point of view. Satisfactory effects of hazardousmetal ionsremoval from drilling muds were achieved using 2 to 5 g of zeolite. The obtained results proved that the natural zeolite constitutes an important material for efficient removal of hazardousmetalionsfrom drilling mud wastewater.
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