Design and Costs Analysis of Hydrogen Refuelling Stations Based on Different Hydrogen Sources and Plant Configurations

In this study, the authors present a techno-economic assessment of on-site hydrogen refuelling stations (450 kg/day of H2) based on different hydrogen sources and production technologies. Green ammonia, biogas, and water have been considered as hydrogen sources while cracking, autothermal reforming, and electrolysis have been selected as the hydrogen production technologies. The electric energy requirements of the hydrogen refuelling stations (HRSs) are internally satisfied using the fuel cell technology as power units for ammonia and biogas-based configurations and the PV grid-connected power plant for the water-based one. The hydrogen purification, where necessary, is performed by means of a Palladium-based membrane unit. Finally, the same hydrogen compression, storage, and distribution section are considered for all configurations. The sizing and the energy analysis of the proposed configurations have been carried out by simulation models adequately developed. Moreover, the economic feasibility has been performed by applying the life cycle cost analysis. The ammonia-based configurations are the best solutions in terms of hydrogen production energy efficiency (>71%, LHV) as well as from the economic point of view, showing a levelized cost of hydrogen (LCOH) in the range of 6.28 EUR/kg to 6.89 EUR/kg, a profitability index greater than 3.5, and a Discounted Pay Back Time less than five years.

A Methodology for Flexible Implementation of Collaborative Robots in Smart Manufacturing Systems

Small-scale production is relying more and more on personalization and flexibility as an innovation key for success in response to market needs such as diversification of consumer preferences and/or greater regulatory pressure. This can be possible thanks to assembly lines dynamically adaptable to new production requirements, easily reconfigurable and reprogrammable to any change in the production line. In such new automated production lines, where traditional automation is not applicable, human and robot collaboration can be established, giving birth to a kind of industrial craftsmanship. The idea at the base of this work is to take advantage of collaborative robotics by using the robots as other generic industrial tools. To overcome the need of complex programming, identified in the literature as one of the main issues preventing cobot diffusion into industrial environments, the paper proposes an approach for simplifying the programming process while still maintaining high flexibility through a pyramidal parametrized approach exploiting cobot collaborative features. An Interactive Refinement Programming procedure is described and validated through a real test case performed as a pilot in the Building Automation department of ABB in Vittuone (Milan, Italy). The key novel ingredients in this approach are a first translation phase, carried out by engineers of production processes who convert the sequence of assembly operations into a preliminary code built as a sequence of robot operations, followed by an on-line correction carried out by non-expert users who can interact with the machine to define the input parameters to make the robotic code runnable. The users in this second step do not need any competence in programming robotic code. Moreover, from an economic point of view, a standardized way of assessing the convenience of the robotic investment is proposed. Both economic and technical results highlight improvements in comparison to the traditional automation approach, demonstrating the possibility to open new further opportunities for collaborative robots when small/medium batch sizes are involved.

Development of Cave Tourism in the Domica Area in Slovakia

The purpose of the study. The main goal of the study is to determine the most effective solutions for the development of cave tourism and medical tourism, as well as the standard of living and infrastructure of the region, based on the used literature and the questionnaire research on tourism development. Applied methods. The study starts with information about the natural and geological heritage found in the Domica region in Slovakia. It continues with the discovery, construction and characterization of the most significant caves from a tourist and economic point of view. Following the professional characterization, the questionnaire research developed and evaluated in the last stage of the study analyzes the possibility of the development of cave tourism and health tourism in the immediate vicinity of the Domica Cave based on the opinions, remarks and experiences of the service providers in the area. Outcomes. Caves are called natural underground cavities that have formed as a result of geomorphological and geophysical processes under different natural conditions. The caves in the karst are dissolved or are created by the weathering of the bedrock, while after the leakage of gases, caves form as cavities in the volcanic rocks. Few countries have as many different underground karst formations as Slovakia, with 7,014 known caves, of which only 18 can be visited. Discovering these underground wonders is a new challenge for hikers. Interest in caves peaked in the 20th century, when the desire to return to nature and improve the health of patients with respiratory diseases (speleotherapy) became the leading motivation. Today, caves are most often used for recreation. Nevertheless, within geotourism a popular way to explore caves is caving and the associated extreme or less extreme sports that only came to the fore in the 21st century. The results of the research of this study are sufficient evidence that the region is suitable for the development of cave tourism and medical tourism, for which the most obvious solution is to create an international geopark.

Electric or Internal Combustion Engines for Passenger Cars? – Environmental and Economic Aspects

The paper is focused on fuels, their users - engines and the end-user, the vehicles, from an environmental and economic point of view. The basic characteristics of potential fuels for internal combustion engines, as well as possible sources of electricity, are analysed. A comparative analysis of characteristics of vehicle propulsion with gasoline, diesel fuel, compressed natural gas, liquefied petroleum gas and electricity was performed. The research has shown that the application of vehicles with an electric motor is ecologically justified only in cases of obtaining electricity in an environmentally friendly way and that in other cases there is no profit in an ecological sense. From an economic point of view, if there were no subsidies to manufacturers and buyers of electric cars, they would not be competitive with internal combustion engines now. Within the research, potential solutions for reducing air pollution and improving the quality of life in cities have been proposed.

Liquid-liquid extraction of Pt(IV) from hydrochloric acid solutions using PPG 425 – NaCl – H2O system

Today, metal extraction from e-waste is beneficial from both an environmental and economic point of view. Natural resources of metals, especially platinum group metals, are limited. At the same time, the amount of waste containing many valuable elements continues to grow. In this work, we studied the extraction of Pt (IV) from hydrochloric acid solutions using polypropylene glycol 425 (PPG 425). In the course of the experimental work, the dependence of the platinum extraction degree on the influence of hydrochloric acid concentration and medium pH in the polypropylene glycol 425 - sodium chloride - water system have been established. The maximum recovery (distribution coefficient > 3,5) has been achieved in the presence of 2 M HCl in an aqueous two-phase system (ATPS), which allows the use of the proposed system for the extraction of platinum from leaching solutions.

Green methods that are used to ensure the sustainable development of the environment and the society

Nowadays, pollution is one of the biggest challenges for human society. Many types of research are directed toward finding sustainable solutions with minimum or no environmental impact. The contaminants affect the ecosystem components and the people's health equally. Cardiovascular and cancer are only two examples of diseases for which air and food adulteration are directly influenced. For each situation, the conditions need to be evaluated. Environmental accidents or rehearsal ones can determine the risk sources. Regardless of the case, prevention measures are always recommended. Different organic wastes recovery represents a possible solution ensuring an endurable process. Such an approach has to be also looked at from an economic point of view. Renewable natural raw materials usually have lower costs. Independent of the considered strategies, they all have to be based on two pilings. One acts by the authority’s involvement using legislation and standards, and the other refers to society through awareness and implication. The paper highlights some of the most recent and significant findings regarding eco-friendly and sustainable techniques newly developed that were presented in recently published articles. The topics considered essential for this approach regarded the improvements made to increase the city life, the industrial environment, and the laboratory techniques.

Restart tourism | build the future

PurposeThis viewpoint aims to explore the question: How can we restart and monitor the path towards the tourism of the future?Design/methodology/approachThis paper identifies the progress made at scientific, institutional, political and technological levels, and how it is possible to foresee that we will enter in a new era of tourism indicators.FindingsA significant body of literature clearly demonstrates that tourism cannot be viewed simply from an economic point of view as it has a great influence on sociocultural and environmental dimensions. The impact of tourism and how to ensure its long-term success has been invoked for the last few decades, leading to the direct consideration of sustainability indicators in a wide array of scientific publications. However, despite significant advances, the lack of funding, lack of support or interest from the political community, bureaucracies or lack of methodological guidance and of technical skills along the entire value chain pose clear challenges to the development and adoption of wide data systems to support sustainable tourism policies.Originality/valueThe paper sheds light on the Portuguese position regarding the recovery of the tourism sector in the aftermath of the COVID-19 pandemic. It also highlights the commitment to knowledge and monitoring of sustainability in tourism, articulated at international level, and how this is essential in order to make progress and to overcome the challenges facing the sector. At the same time, it demonstrates how fundamental it is to identify solutions to boost the potential of tourism as an economic, social, environmental and cultural phenomenon.

Mechanical Properties and Chemical Stability of Bathroom Wall Composites Manufactured from Recycled Polyethylene Terephthalate (PET) Mixed with Cocoa Hulls Powder

The need to protect our environment by eliminating plastic waste as much as possible and by recycling waste from agricultural residue, has led us to formulate composites based on polyethylene terephthalate (PET) loaded with powder from the cocoa shell. The cocoa hulls were prior treated with organosolv process to improve the fiber-matrix interaction. This research is aimed at manufacturing composite wall tiles from recycled PET reinforced with cocoa hull powder (CCP). The composites were manufactured by the melt-mixing method followed by compression molding. The mechanical, physico-chemical properties and the stability to environmental conditions were evaluated. The results showed that the incorporation of cocoa powder at a content of 20-30% in the matrix consisting of PET gave rise to a composite material with good physico-mechanical and chemical properties suitable for use in several sectors. In the construction industry, in particular as wall covering as a replacement for tiles, these x from an economic point of view cost less and compared to clays which consumes enormous amount of energy for the elaboration of ceramics. The study showed that the optimum powder weight proportion for the optimal properties of the composite were achieved at 30% powder weight proportion. The maximum tensile strength of 60.3 MPa, flexural strength of 19.5 MPa, impact strength of 10.3 MPa and water absorption 1.34% were obtained. Water absorption of the tiles increased with the cocoa powder weight. Compare to the ceramic tile this value of water absorption test is in range and show that this composite tile is suitable for use as bathroom tile.

The Use of Digitization in Small and Medium-Sized Agricultural Enterprises: Evidence from the Czech Republic

This paper presents the results of the research focused on the issues of digitization of agriculture in the context of current global developments and on the need to increase the amount of food produced in order to feed the continuously growing world population. The paper aims to analyze the use of the selected digitization tools in the crop production in the Czech Republic by small and medium-sized enterprises and to evaluate that from the economic point of view. To achieve the objectives, the desk research, the analysis and evaluation of secondary sources, and the method of directed interviews with managers and employees of the selected business entity were used. The research results evidence the positives and negatives of the use of the selected digitization tools within the crop primary production and represent the basis for further research aimed at the development of economic and financial management of small and medium-sized agricultural enterprises in the context of Agriculture 4.0 concept.

Effect of transplanting dates on yield attributing characters of tomato (Lycopersicon esculentum Mill.) variety

The research was conducted on the field of Chagunarayan municipality (Tathali) from 23rd March to 17th June 2020 to observe the effect date of transplanting on attributing character of tomato Genotype. 23rd March, 6th April, 21st April, and 6th May are the four sowing dates laid out in the RCBD design with three replications. And the data were observed in 10 days intervals for each planting time. The attributing character like plant height, leaf number, no of branches shows positive impact for early shown plant species, and development for later sowing date shows decreasing result. Therefore, the species planted before the planting time is beneficial from an economic point of view where the plant shows a positive growth rate on attributing character, and it can be considered for further research programs as well.