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In the last 20 years, with the liberalization of the economy, and the trend of industrial globalization, people have gradually paid more attention to environmental protection. With the tremendous advances in information technology, enterprises facing such a severe impact on the business operations, business administrative models must be innovative and adaptable in order to survive and flourish. The paper industry is not only a highly polluting industry, but in the case of long-term overcapacity, the price of paper products is often suppressed, which lowers profitability. The purpose of this study, which is based on the production data of a paper company, is to pose a mathematical programming decision model which integrates green manufacturing technologies, activity-based costing (ABC), and the theory of constraint (TOC), this model should assist in preparing the best production plans, and achieve the optimal profitable product mix. In addition, this study also proposes that the most popular related technologies developed by Industry 4.0 be applied to production control in recent years in order to enhance production efficiency and quality. The findings of this study should contribute to the improvement of the competitiveness of the paper industry, and provide insights into the value of an integrated mathematical programming model applied for product-mix decision. At the same time, we have also applied the related technologies developed by Industry 4.0 to machine maintenance and quality control in manufacturing workshops. With its tremendous benefits, we can actively arouse the industry&rsquo, s understanding of, and attention to, Industry 4.0, thereby increasing the interest in industrial 4.0-related technology investments.

This study analyses how Spanish universities are communicating their commitment to sustainability to society. That entailed analysing the content of their websites and their scientific papers in sustainability science and technologies and measuring the impact of such research in social media. Results obtained from bibliometric approaches and institutional document analysis attest to intensified interest in sustainability among Spanish universities in recent years. The findings revealed an increase in the number of universities using terms associated with sustainability to designate the governing bodies. The present study also uses an activity index to identify universities that devote high effort to research on sustainability and seven Spanish universities were identified with output greater than 3% of the total. Mentions in social media were observed to have grown significantly in the last 10 years, with 38% of the sustainability papers receiving such attention, compared to 21% in 2010. Publications in open access journals have had a greater impact on social media, especially on Twitter and Facebook. The analysis of university websites showed that only 30% had social media accounts and only 6% blogs specifically designed to disseminate their sustainability activities, This research was funded by the Madrid Regional Government and the European Social Fund, Project “Towards the Consolidation of Inclusive Cities: A Challenge for Madrid” (H2019/HUM-5744)

The number of elderly people as a proportion of the world’s population is growing significantly. Special attention to the accessibility and mobility requirements of this group is needed. The contribution of this paper is a review of travel patterns, mode preferences, infrastructure solutions, accessibility indices, mode choice models and datasets as they relate to elderly mobility. Key findings highlight the role of residential location characteristics in shaping elderly travel patterns, helping to explain why research on elderly travel has largely relied on case studies to date. The review also summarizes a range of indices that have been developed to measure public transport and walking accessibility among the elderly, including distance and time-based methods. Future research should consider the dominance of private transport in facilitating elderly mobility and its implications for cities experiencing an aging population.

Sustainability is instituting annual awards to recognize the most outstanding papers in the areas of environmental, cultural, economic, technical and social sustainability of human beings published in Sustainability. [...]

In addition to the traditional so-called Arctic states, non-Artic states and some other international organisations are now showing a growing interest in this area. China, for example, has achieved some progress, since becoming an Arctic Council permanent observer, through participation in resource development in the region and strengthening its bilateral relations with the Arctic states. The present study examines China’s Arctic policy and its implications for the governance of the Arctic Ocean. It also provides an insight into the existing relevant international legal instruments and examines China’s interest in the participation, governance, and resource protection activities in the Arctic Ocean region, to successfully implement Chinese Arctic policy. To this end, the study examines the connection between the “white paper” and “China’s Arctic Policy”, in the context of executing the “Belt and Road Initiative”, in particular the “Arctic Silk Road”. The study concludes that China intends to perform a dynamic role in governing the Arctic Ocean, as a less challenging but cooperative partner in this region.

This article investigates the potential environmental impacts of four-layer printed circuit board (PCB) production from cradle to grave. The study starts with a lifecycle assessment of conventional PCB production. Then, the alternative materials of polyethylene terephthalate (PET), polylactic acid (PLA)/glass fiber composite and paper are investigated for the substrate. A conventional PCB adopts copper as the conductive material and requires an etching process. The environmental impacts of changing the conductive deposition method to an additive method by printing silver nanoparticles is studied. In a conventional PCB, electricity generation contributes 41% of the global warming potential (GWP) and 38% of the abiotic resource depletion (ADP), in the fossil category. By applying an additive manufacturing method, the GWP of PCB manufacturing can be reduced to 14% of that of the conventional method. A sensitivity analysis of silver recycling illustrates that a 40% higher silver recycling rate would decrease the GWP of silver material by about 48–60%. Uncertainty in the energy consumption of PCB production would alter the environmental impacts, however, even with the most conservative energy consumption in a conventional PCB production method, the environmental impacts of the additive method are about five times lower than those of conventional PCB production.

The fertilizer framework in the European Union has recently been reviewed by EU Regulation 1009/2019 that excluded sewage sludge from the list of the possible constituents of organic fertilizers relying on their origin, not on their quality. This paper aimed to carry out a complete characterization of sewage sludge obtained from a pharmaceutical manufacturing process (PDSS) to demonstrate that sewage sludge obtained from a standardized and controlled manufacturing process can be safely recycled as organic fertilizer. The agronomic and environmental characteristics of the PDSS product were analyzed and compared to other organic fertilizers. Its fertilizing potential was also evaluated through plant growth trials. PDSS was characterized by a high concentration of total N (6.6% w/w), which was all present in organic form. PDSS also showed a low concentration of heavy metals, an absence of pathogens and low concentrations of organic contaminants. Plant growth trials showed that the PDSS was able to improve lettuce and carrot growth (+25 and +46% of dry weight compared to the unfertilized control), as well as their physiological status. Considering all the results, the exclusion of sewage sludge relying only on its origin and not on its quality appears to conflict with the principles of the circular bioeconomy.

The potential of agroforestry to improve livelihoods and mitigate climate change and environmental degradation has been widely recognized, especially within the context of climate-smart agriculture. However, agroforestry opportunities have not been fully exploited because of several reasons, among which are adverse policies and legislations. However, many countries do not have a full understanding of how their policy and institutional environment may affect agroforestry development. We aim to fill this gap by looking at the particular case of Chad. The method used included examining data from: (i) literature reviews of important national and international polices, strategies, and legislation governing access to land and trees, among which are ‘La Loi 14’, Chad’s 2010 poverty reduction strategy paper, draft zero of the National Environmental Policy, (ii) interviews and focus group discussions with NGOs, government officials, and farmers, and (iii) surveys with 100 households. Results show that Chad has no specific agroforestry policy but opportunities for agroforestry can be found in some of the above-mentioned policy documents and government strategies. Most stakeholders interviewed had positive attitudes towards agroforestry, but uptake of the practice is handicapped by poor understanding of the forestry law by farmers and forestry officials. Gaps in existing laws give room for rent-seekers to collect individual (USD 272–909) and collective (USD 36–1818) access fees to trees on both forest and farmland. We propose that the government of Chad should unmask elements of agroforestry in existing policies and policy instruments to demonstrate its importance in responding to livelihood and environmental challenges in the country.

Due to their properties, silver nanoparticles (AgNPs) are widely used in consumer products. The widespread use of these products leads to the release of such nanoparticles into the environment, during manufacturing, use, and disposal stages. Currently there is a high margin of uncertainty about the impacts of nano products on the environment and human health. Therefore, different approaches including life cycle assessment (LCA) are being used to evaluate the environmental and health impacts of these products. In this paper, a comparison between four different AgNP synthesis methods was conducted. In addition, four textile products that contain AgNPs were subjected to comparison using LCA analysis to assess their environmental and public health impacts using SimaPro modeling platform. Study results indicate that using alternative methods (green) to AgNPs synthesis will not necessarily reduce the environmental impacts of the synthesizing process. To the best of our knowledge, this is the first study that has compared and assessed the environmental burdens associated with different nanosilver-based textile products at different disposal scenarios. The synthesis of 1 kg of AgNPs using modified Tollens’ method resulted in 580 kg CO2 eq, while 531 kg CO2 eq resulted from the chemical approach. Furthermore, the manufacturing stage had the highest overall impacts as compared to other processes during the life cycle of the product, while the product utilization and disposal stages had the highest impacts on ecotoxicity. Sensitivity analysis revealed that under the two disposal scenarios of incineration and landfilling, the impacts were sensitive to the amount of AgNPs.

This work addresses the joint management of residual microalgae and pine wood waste through pyrolysis to obtain a solid product for its use as soil amendment and two other by-products (liquid and gaseous) that can be used for energy purposes. Two management routes have been followed. The first route is through the co-pyrolysis of mixtures of both residual materials in several proportions and the later use of their solid fraction for soil amendment. The second route is the pyrolysis of pine wood waste and its direct combination with dried residual microalgae, also using it as soil amendment. The solid fraction assessment shows that from seven solid products (biochar) three stand out for their positive applicability in agriculture as soil amendment. In addition, they also present the benefit of serving as carbon sink, giving a negative balance of CO2 emissions. However, caution is suggested due to biochar applicability being subject to soil characteristics. To ensure the sustainability of the overall process, the energy available in liquid and gaseous fractions has been assessed for covering the drying needs of the residual microalgae in both cases. These results suggest that the pyrolysis process is a sustainable way to manage specific evaluated residues and their products.

Environmental concern for our planet has changed significantly over time due to climate change, caused by an increasing population and the subsequent demand for electricity, and thus increased power generation. Considering that natural gas is regarded as a promising fuel for such a purpose, the need to integrate carbon capture technologies in such plants is becoming a necessity, if gas power plants are to be aligned with the reduction of CO2 in the atmosphere, through understanding the capturing efficacy of different absorbents under different operating conditions. Therefore, this study provided for the first time the comparison of available absorbents in relation to amine solvents (MEA, DEA, and DEA) CO2 removal efficiency, cost, and recirculation rate to achieve Climate change action through caron capture without causing absorbent disintegration. The study analyzed Flue under different amine-based solvent solutions (monoethanolamine (MEA), diethanolamine (DEA), and methyldiethanolamine (MDEA)), in order to compare their potential for CO2 reduction under different operating conditions and costs. This was simulated using ProMax 5.0 software modeled as a simple absorber tower to absorb CO2 from flue gas. Furthermore, MEA, DEA, and MDEA adsorbents were used with a temperature of 38 &deg, C and their concentration varied from 10 to 15%. Circulation rates of 200&ndash, 300 m3/h were used for each concentration and solvent. The findings deduced that MEA is a promising solvent compared to DEA and MDEA in terms of the highest CO2 captured, however, it is limited at the top outlet for clean flue gas, which contained 3.6295% of CO2 and less than half a percent of DEA and MDEA, but this can be addressed either by increasing the concentration to 15% or increasing the MEA circulation rate to 300 m3/h.

Synthetic gas generated from the gasification of biomass feedstocks is one of the clean and sustainable energy sources. In this work, a fixed-bed downdraft gasifier was used to perform the gasification on a lab-scale of rice husk, sawdust, and coconut shell. The aim of this work is to find and compare the synthetic gas generation characteristics and prospects of sawdust and coconut shell with rice husk. A temperature range of 650–900 °C was used to conduct gasification of these three biomass feedstocks. The feed rate of rice husk, sawdust, and coconut shell was 3–5 kg/h, while the airflow rate was 2–3 m3/h. Experimental results show that the highest generated quantity of methane (vol.%) in synthetic gas was achieved by using coconut shell than sawdust and rice husk. It also shows that hydrogen production was higher in the gasification of coconut shell than sawdust and rice husk. In addition, emission generations in coconut shell gasification are lower than rice husk although emissions of rice husk gasification are even lower than fossil fuel. Rice husk, sawdust, and coconut shell are cost-effective biomass sources in Bangladesh. Therefore, the outcomes of this paper can be used to provide clean and economic energy sources for the near future.

In the whole process of cement production, the electricity consumption of a raw material mill accounts for about 24% of the total. Based on the statistics of the electricity consumption of the raw material mill system of 1005 production lines in China between 2014 and 2019, it is found that the average electricity consumption of the raw material preparation process of all clinker production lines between 2014 and 2019 was 25.2 kWh/t. The average electricity consumption of different-tonnage production lines varies with time. In comparison with high-tonnage ones, the electricity consumption of low-tonnage production lines has wider distribution. The average electricity consumption of raw material mill dropped from 30.88 kWh/t in 2014 to 16.13 kWh/t in 2019, with a drop of more than half. At present, the raw material preparation process of new drying-process cement production enterprises mainly includes middle unloading drying tube mill raw material preparation system, vertical mill raw material final grinding system, and roller press raw material final grinding system. This paper compares the characteristics of several grinding systems and summarizes their influence on the electricity consumption.

The composting of green waste (GW) proceeds slowly due to the presence of slowly degradable compounds in that substrate. The introduction of amendments and bulking materials can improve organic matter degradation and end-product quality. However, additional strategies such as two-stage composting, can deal with the slow degradation of green waste. This paper evaluates the effect of two-stage composting on the process and end-product quality of the co-composting of green waste and food waste amended with sawdust and phosphate rock. A pilot-scale study was developed using two treatments (in triplicate each), one being a two-stage composting and the other being a traditional composting. The two treatments used the same mixture (wet weight): 46% green waste, 19% unprocessed food waste, 18% processed food waste, 13% sawdust, and 4% phosphate rock. The traditional composting observed a higher degradation rate of organic matter during the mesophilic and thermophilic phases and observed thermophilic temperatures were maintained for longer periods during these two phases compared to two-stage composting (i.e., six days). Nonetheless, during the cooling and maturation phases, the two treatments had similar behaviors with regard to temperature, pH, and electrical conductivity, and the end-products resulting from both treatments did not statistically differ. Therefore, from this study, it is concluded that other additional complementary strategies must be evaluated to further improve GW composting.

Cheese whey is a waste produced in the dairy industry which generates problems if it is dumped directly into the sewer due to its high organic load. An alternative for cheese whey management is anaerobic digestion, a biological process that transforms organic matter into biogas and digestate, two products with significant energy and agricultural potential. This work was aimed at contributing to the building of knowledge about the anaerobic degradation of cheese whey, developing a bibliometric analysis, and tracing trends in related research from 2010 up to the present, using PRISMA® to develop a systematic review based on Scopus® and using Excel® and bibliometric software (VosViewer® and RefViz®) for the identification of information. Our results show that the research around cheese whey is relatively recent and that the highest percentage of publications is from 2018 onwards. Twelve variables of the anaerobic cheese whey degradation process were identified and grouped into five factors: substrate, reactor configuration, digestate analysis, microbiological analysis, and inoculum. Likewise, it was identified that most of the anaerobic processes allow the implementation of the circular economy into the dairy sector. In conclusion, the application of anaerobic digestion in the dairy sector can help to close the productive cycles, produce biofuels, and reduce pollution.

The use of food additives (such as dyes, which improve the appearance of the products) has become more prominent, due to the rapid population growth and the increase in demand for beverages and processed foods. The dyes are usually found in effluents that are discharged into the environment without previous treatment; this promotes mass contamination and alters the aquatic environment. In recent years, advanced oxidation processes (AOPs) have proven to be effective technologies used for wastewater treatment through the destruction of the total organic content of toxic contaminants, including food dyes. Studies have shown that the introduction of catalysts in AOPs improve treatment efficiency (i.e., complete decomposition without secondary contamination). The present review offers a quick reference for researchers, regarding the treatment of wastewater containing food dyes and the different types of AOPs, with different catalyst and nanocatalyst materials obtained from traditional and green chemical syntheses.

Granular organic fertilizers have been increasingly used in agriculture due to the longer delivery of nutrients to plants and the milder impact on the environment. The aim of this study was to determine the energy, environmental and economic efficiency of granular and non-granular organic fertilizers. Four technological scenarios of organic fertilizer use were used for comparative assessment: (1) manure fertilization (16.0 t ha−1), (2) manure fertilization (30.0 t ha−1), (3) manure pellet fertilization (2.0 t ha−1), and (4) fertilization with meat and bone meal pellets (0.7 t ha−1). Experimental studies using the mass flow method of laser spectroscopy were performed to evaluate the comparative environmental impact of granular and non-granular organic fertilizers. Economic assessment was performed for mechanized technological operations of loading, transportation and distribution of organic fertilizers, estimating the price of aggregates used and fuel consumed, the costs of individual technological operations and other indirect costs. The results showed that for mechanized technological operations, when fertilizing with granular organic manure and meat and bone meal fertilizer, energy consumption is 3.2 to 4.0 times lower compared to fertilization with manure. The average ammonia (NH3) emissions from granular organic fertilizers were found to be six times lower than from non-granular organic fertilizers. The lowest costs for mechanized works were incurred when using meat and bone meal pellets, the highest economic benefits of organic fertilizers by elements was when using manure 30 t ha−1, and the highest costs for organic fertilizers were incurred when using manure pellets.

Microalgae biofuel is expected to be an ideal alternative to fossil fuels to mitigate the effects of climate change and the energy crisis. However, the production process of microalgae biofuel is sometimes considered to be energy intensive and uneconomical, which limits its large-scale production. Several cultivation systems are used to acquire feedstock for microalgal biofuels production. The energy consumption of different cultivation systems is different, and the concentration of culture medium (microalgae cells contained in the unit volume of medium) and other properties of microalgae vary with the culture methods, which affects the energy consumption of subsequent processes. This review compared the energy consumption of different cultivation systems, including the open pond system, four types of closed photobioreactor (PBR) systems, and the hybrid cultivation system, and the energy consumption of the subsequent harvesting process. The biomass concentration and areal biomass production of every cultivation system were also analyzed. The results show that the flat-panel PBRs and the column PBRs are both preferred for large-scale biofuel production for high biomass productivity.

More than 124 million tons of oranges are consumed in the world annually. Transformation of orange fruit generates a huge quantity of waste, largely composed of peels. Some attempts to reuse by-products derived from citrus waste have been proposed for energy production, nutrient source or pharmaceutical, food and cosmetic industries. However, their use in the building sector had not been researched. In this study, orange peels, in five different ratios, from 100% of wet peels to 75% and from 0% of dry peels to 25%, were submitted to a thermo-compression procedure. They were evaluated according to their physical (bulk density, water absorption, thickness swelling, surface soundness and thermal conductivity) and mechanical properties (bending strength and modulus of elasticity). The results showed that orange peels can be used as thermal insulation material. The addition of dried peels makes the structure of the board heterogeneous and thus increases its porosity and causes the loss of strength. Hence, the board with the sole use of wet peel, whose thermal conductivity is 0.065 W/mK while flexural strength is 0.09 MPa, is recommended.

Solid sago waste is a potential source of producing renewable energy in the form of biogas. This study investigated the effects of solid sago waste particle size, biological pretreatment using a microbial consortium of lignocelluloses, pretreatment with NaOH, and the ratio between solid sago waste and cow rumen based on the biogas production rate. Several variations of these conditions were used to achieve this. The anaerobic digestion process was conducted over two months at 30.42 °C ± 0.05 °C, and the biogas production rate was measured every two days. The 1:1 ratio showed better results compared to the 2:1, because it allows the bacteria to achieve metabolic balance. The highest cumulative biogas production (27.91 mL/g TS) was generated when the sago waste underwent milling (±1 mm), pretreatment with 4% NaOH g/g TS, and treatment with microbial consortium 5% v/v at a 1:1 ratio of solid sago waste to the rumen.

Leak detection and repair (LDAR) plays an important role in controlling the fugitive emission of volatile organic compound (VOC) from chemical enterprises. At present, many policies and standards issued in China have set clear requirements for implementing LDAR in the pharmaceutical industry. In this study, the LDAR work of nine typical pharmaceutical enterprises was selected for analysis to allow investigation of the characteristics of VOC emissions from leaking equipment components. Some suggestions for controlling VOC are proposed to provide a reference for managing the fugitive emissions of VOC from pharmaceutical enterprises. The results showed that the number of equipment components used by the pharmaceutical enterprises ranged from several thousand to more than 20,000, which is lower than that in oil refining and coal chemical enterprises. The predominant leaky component was the flange, which accounted for 56.31% of the total, followed by connectors (21.51%) and valves (18.53%). Light liquid medium components accounted for the largest proportion of equipment (52.83%) on average, followed by gas medium components (45.52%, on average). Heavy liquid medium components, which are rarely used in pharmaceuticals, accounted for only 1.65%. The average leak ratio of the components in the pharmaceutical industry was approximately 0.99%. The leak ratio of the open-ended line was much higher than that of other types of components, reaching an average of 5.00%, while that value was only 0.92% for the flange, despite the numbers and proportion of them that were in use. The total annual VOC leakage from the nine pharmaceutical enterprises studied in this work was 20.11 tons, with an average of 2.23 tons per enterprise and an average of 0.22 kg/a per equipment component. Flanges, connectors, and valves were the top three contributors to leakage, generating 39.17%, 38.72%, and 16.79% of the total, respectively, and a total proportion of 94.68%. Although the number of pumps accounted for only 0.15% of the components, it generated 1.94% of the leakage. In terms of different production processes, the greatest unit product leakage came from the bulk production of chemicals used for pharmaceuticals, reaching 0.085 t/a. The production from traditional Chinese medicine enterprises was the lowest (0.011 t/a), which was only 12.80% of the leakage from the bulk production of chemicals for drugs. The leakage of VOC from the equipment components in the nine enterprises was reduced, to varying degrees, using LDAR. The overall reduction ratio was between 23.55% and 67.72%, with an average of 44.02%. The reduction in leakage was relatively significant after the implementation of LDAR, however, there is still room for improvement. Pharmaceutical enterprises should improve their implementation of LDAR and reduce VOC leakage by reducing the number of inaccessible components used and increasing the repair ratio of leaky components. Controlling the source of component leakage, which should be emphasized, can be realized by cutting down the number of components used, adopting low-leakage equipment, and putting anti-leakage measures in place.

Small-scale anaerobic digestion (AD) can be an effective organic waste management system that also provides energy for small businesses and rural communities. This study measured fuel production from digestions of single and mixed feedstocks using an unheated, 2 m3 digester operated continuously in a temperate climate for over three years. Using local food waste, brewery waste, grease waste, and agricultural residues, this study determined that small-scale AD co-digestions were almost always higher yielding than single feedstocks during psychrophilic operation and seasonal temperature transitions. Agricultural residues from Miscanthus&nbsp, x&nbsp, giganteus had the greatest impact on biomethane production during co-digestion (4.7-fold greater average biogas %CH4), while mesophilic digestion of brewery waste alone produced the most biogas (0.76 gCH4 gVS−1 d−1). Biogas production during the transition from mesophilic to psychrophilic was temporarily maintained at levels similar to mesophilic digestions, particularly during co-digestions, but biogas quality declined during these temperature shifts. Full-time operation of small-scale, unheated AD systems could be feasible in temperate climates if feedstock is intentionally amended to stabilize carbon content.

Lignin is one of the wood and plant cell wall components that is available in large quantities in nature. Its polyphenolic chemical structure has been of interest for valorization and industrial application studies. Lignin can be obtained from wood by various delignification chemical processes, which give it a structure and specific properties that will depend on the plant species. Due to the versatility and chemical diversity of lignin, the chemical industry has focused on its use as a viable alternative of renewable raw material for the synthesis of new and sustainable biomaterials. However, its structure is complex and difficult to characterize, presenting some obstacles to be integrated into mixtures for the development of polymers, fibers, and other materials. The objective of this review is to present a background of the structure, biosynthesis, and the main mechanisms of lignin recovery from chemical processes (sulfite and kraft) and sulfur-free processes (organosolv) and describe the different forms of integration of this biopolymer in the synthesis of sustainable materials. Among these applications are phenolic adhesive resins, formaldehyde-free resins, epoxy resins, polyurethane foams, carbon fibers, hydrogels, and 3D printed composites.

The current study presents a detailed evaluation and comparison between two integrated anaerobic–aerobic systems for biological wastewater treatment under equal conditions in all aspects (wastewater characteristics, climatic conditions, reactor sizing, and even the measurement methods). The two examined systems are (i) a hybrid upflow anaerobic sludge blanket (hybrid UASB) coupled with integrated fixed-film activated sludge (IFAS) and (ii) a conventional UASB coupled with activated sludge (AS). The present comparative study aims to evaluate and assess the effect of adding carrier-filling media on the performance of the classical integrated UASB-AS. The two parallel pilot-scale systems, hybrid UASB-IFAS and UASB-AS, were installed and operated at a wastewater treatment plant. Three sets of experiments were conducted to examine the influence of the hydraulic retention time (HRT) on the consequent organic and hydraulic loads, temperature, and recirculation rate of the proposed systems. The main results showed that the two investigated systems had a comparably high efficiency for the removal of organic matters and ammonia. Moreover, a paired sample t-test indicated there was a statistically significant effect of the filling media, and the performance of the hybrid UASB-IFAS increased significantly compared with that of the UASB-AS system. An additional benefit of the filling media on the hybrid system was its high stability when changing the organic and hydraulic loads. The optimum HRT was 6 h, with a total chemical oxygen demand (TCOD) percentage removal of approximately 95% in both examined systems. Treatment of sewage under high and low temperatures indicated that increasing the temperature improved the efficiency of the overall process for both systems significantly.

Freeze-drying is one of the most expensive and most energy intensive processes applied in food technology. Therefore, there have been significant efforts to reduce the freeze-drying time and decrease its energy consumption. The aim of this work was to analyze the effect of pulsed electric field (PEF), ultrasound (US), and hybrid treatment (PEF-US) and compare them with the effect of blanching (BL) on the freeze-drying kinetics, energy consumption, greenhouse gasses emission, and physical quality of the product. The freeze-drying process was applied to red bell peppers after pretreatment operations. Results showed that application of BL, PEF, US, or PEF-US reduces freeze-drying time and decreases energy consumption. Among the tested methods, the combination of PEF performed at 1 kJ/kg and US was the most effective in reduction of greenhouse gas emission. BL samples exhibited the highest porosity, but from a statistical point of view, most of the PEF-US treated materials did not differ from it. The smallest color changes were noted for US pre-treated bell peppers (ΔE = 9.4), whereas BL, PEF, and PEF-US material was characterized by ΔE of 15.2–28.5. Performed research indicates the application of pre-treatment may improve the sustainability of freeze-drying process and quality of freeze-dried bell pepper.

Research approaches on the use of ecotechnologies like ozone assisted processes for the decolorization of textiles are being explored as against the conventional alkaline reductive process for the color stripping of the cotton textiles. The evaluation of these ecotechnologies must be performed to assess the environmental impacts. Partial &ldquo, gate to gate&rdquo, Life Cycle Assessment (LCA) was implemented to study the ozone based decolorization process of the reactive dyed cotton textiles. Experiments were performed to determine input and output data flows for decolorization treatment of reactive dyed cotton textile using the ozonation process. The functional unit was defined as &ldquo, treatment of 40 g of reactive dyed cotton fabric to achieve more than 94% color stripping&rdquo, Generic and specific data bases were also used to determine flows, and International Life Cycle Data system (ILCD) method was selected to convert all flows into environmental impacts. The impact category &ldquo, Water resource depletion&rdquo, is the highest for all the ozonation processes as it has the greatest relative value after normalization amongst all the impact indicators. Electricity and Oxygen formation were found to be the major contributors to the environmental impacts. New experimental conditions have been studied to optimize the impacts.

Each year, about 730 million tons of bottom ash is generated in coal fired power plants worldwide. This by-product can be used as partial replacement for Portland cement, favoring resource conservation and sustainability. Substantial research has explored treated and processed coal bottom ash (CBA) for possible use in the construction industry. The present research explores using local untreated and raw CBA in mitigating the alkali&ndash, silica reaction (ASR) of reactive aggregates in concrete. Mortar bar specimens incorporating various proportions of untreated CBA were tested in accordance with ASTM C1260 up to 150 days. Strength activity index (SAI) and thermal analysis were used to assess the pozzolanic activity of CBA. Specimens incorporating 20% CBA achieved SAI greater than 75%, indicating pozzolanic activity. Mixtures incorporating CBA had decreased ASR expansion. Incorporating 20% CBA in mixtures yielded 28-day ASR expansion of less than the ASTM C1260 limit value of 0.20%. Scanning electron microscopy depicted ASR induced microcracks in control specimens, while specimens incorporating CBA exhibited no microcracking. Moreover, low calcium-to-silica ratio and reduced alkali content were observed in specimens incorporating CBA owing to alkali dilution and absorption, consequently decreasing ASR expansion. The toxicity characteristics of CBA indicated the presence of heavy metals below the US-EPA limits. Therefore, using local untreated CBA in concrete as partial replacement for Portland cement can be a non-hazardous alternative for reducing the environmental overburden of cement production and CBA disposal, with the added benefit of mitigating ASR expansion and its associated costly damage, leading to sustainable infrastructure.

The purpose of this work was to determine the optimal percentage of wastewater from cesspool in the mixture of wastes subjected to treatment processes, which will not have a negative impact on the functioning of the collective treatment plant. The study was carried out over a period of two years, with 48 samples of wastewater flowing in from the sewage network and delivered with the slurry tanker collected and subjected to physical and chemical analysis. The analysis included: Biochemical Oxygen Demand (BOD5), Chemical Oxygen Demand (COD), and Total Nitrogen (TN). In addition, the study defined the daily balance of the amount of inflowing and transported wastewater. Based on the analysis carried out, it was found that the unit loads of BOD5, COD and TN in the mixture of wastewater subjected to the treatment process will be at the level of loads assumed in the project, when the share of supplied wastewater, i.e., from cesspool, will be at the level of 5% of the total amount of wastewater. Considering that in the analysed period the total average daily amount of wastewater subjected to the treatment process was 253.5 m3&middot, d&minus, 1, the optimal amount of wastewater delivered should be 12.7 m3 in each day of the week.

Dry anaerobic digestion technology (DADT) is considered a highly feasible way to treat agricultural straw waste; however, most practical operations are always in low efficiency, due to the poor fluidity behavior and complex lignocellulosic structure of straw, which is not easily decomposed by anaerobic bacteria. Hence, it is necessary to further investigate the operation boundary, in order to increase biogas production efficiency for effective applications. In this paper, typical DADTs are reviewed and their suitability for application in China is analyzed. The advantages and disadvantages of different anaerobic digestion processes are evaluated considering pretreatment, organic loading rate, anaerobic digestion temperature, and homogenization of the feedstock and inoculate. The suitability of the DADTs is evaluated considering the accessibility of straw resources and the convenience of biogas use. It is concluded that batch anaerobic digestion processes would be more suitable for the development of southern China due to the prevalence of small-scale agriculture, while continuous anaerobic digestion would be preferable in the north where large-scale agriculture is common. However, the DADTs discussed here need to broad application in China.

The abandonment of coal energy plants in the near future will result in a substantially reduced availability of the coal fly ash broadly used as an efficient supplementary material. In line with the growth of alternative and renewable energy resources, the amount of biomass-based ash rises substantially. Nevertheless, a diverse chemical composition prevents a broader utilization of biomass-based fly ash compared to coal ash on an industrial scale. On this account, the present work is aimed at investigating the basic physical and mechanical properties of concrete mortars modified by a high volume of biomass fly ash (BFA) from wood combustion. Delivered results confirm a significant potential of BFA in the building industry. Experimental analysis of concrete mortars with BFA reveals preservation or even improvement of compressive and bending strength up to 30 wt.% cement replacement. On the contrary, higher dosages induce a gradual decrease in mechanical performance. The performed Life Cycle Assessment analysis reveals the perspective of BFA incorporation taking into account environmental issues considering the ratio between preservation of mechanical performance per normalized endpoint environmental score that allows a direct comparison with other alternatives.

Compared with conventionally collected sewage, source-diverted greywater has a higher potential for on-site treatment and reuse due to its lower contaminant levels and large volume. A new design of granular activated carbon (GAC) biofilters was developed by incorporating unsaturated and saturated zones in a single stage to introduce an efficient, passive, and easy-to-operate technology for greywater on-site treatment at the household scale. The design was customized for its intended application considering various aspects including the reactor&rsquo, s configuration, packing media, and feeding strategy. With the highest hydraulic and organic loadings of 1.2 m3 m&minus, 2 d&minus, 1 and 3.5 kg COD m&minus, 1, respectively, and the shortest retention time of 2.4 h, the system maintained an average total chemical oxygen demand removal rate of 94% with almost complete removal of nutrients throughout its 253 days of operation. The system showed a range of reduction efficacy towards five surrogates representing viruses, bacteria, and Cryptosporidium and Giardia (oo)cysts. A well-functioning biofilm was successfully developed, and its mass and activity increased over time with the highest values observed at the top layers. The key microbes within the biofilter were revealed. Feasibility of the proposed technology was investigated, and implications for design and operation were discussed.

The mechanical harvesting of hemp is a key step toward a profitable use of the product. Various fractions (fiber, seeds, residual biomass) may be recovered, and their correct management is fundamental for complying with the requirements of processors/end users. In the light of the renewed interest for its industrial use (panels and insulators), this work proposes the use of modified commercial machines to implement a field separation of the fibrous fraction of stand-retted hemp, a practice that would be profitable if realized with the systems adopted for textile use. The present work was conducted to test the efficiency of harvesting partially macerated plants by using a modified self-propelled forage harvester (SPFH). In Northern Italy, a hemp crop was stand-retted for four months. Then, an SPFH&mdash, with rotor knives reduced in number from 24 to 12&mdash, was used. Stand-retting made it possible to separate cortical fibers from the inner stem cylinder during harvesting, 53.3% of the material (fibers and shives) was separated automatically by the SPFH together with the chopped bast fiber, while the remaining 46.7% was separated on exiting the launch tube. More than 50% of the fibers were shorter than 5 cm in length, while almost 15% were longer than 10 cm. The SPFH had an effective operating speed of 3.48 km h&minus, 1, and no clogging occurred during the test. Therefore, the combination of stand-retting with harvesting using a modified SPFH could be helpful in obtaining an early separation of fibers from shives, thus facilitating the product treatment during its subsequent processing, e.g., by enhancing the defibration.

The development of textile recycling solutions is an area of intense research and commercialization. Chemical recycling solutions are becoming increasingly popular due to their ability to separate complex blends and retain or improve the value of the original fiber. The chemical recycling of cotton requires a pre-treatment step to reduce the degree of polymerization (DP). The DP can be reduced in a variety of ways, and here, the environmental footprints of two different pre-treatment approaches are examined using life cycle assessment (LCA), sodium hydroxide pre-treatment and sulfuric acid pre-treatment. We find that the acid pre-treatment has a significantly lower environmental footprint across all impact categories calculated. This is attributed to the lower treatment times required and the lower material and energy requirements for the manufacture of chemicals. The results were normalized to show the most significant impact categories for each pre-treatment, and further environmental implications of the pre-treatments are discussed. The findings will aid academia and industry in implementing the most environmentally benign processes in chemical cotton recycling.

The brewing industry generates, as the primary coproduct, brewers&rsquo, spent grain (BSG). In Mexicali, Baja California, Mexico, there are 17 companies that generated 282 tons of BSG by 2016. Cattle feeding is the most common type of disposal for this waste. However, it can be valorized for the production of bioenergy or as a source of added-value products. Therefore, the objective of the present work was to assess the physicochemical properties of the brewers&rsquo, spent grain from a local craft brewery, to choose the most appropriate exploitation route. Chemical and morphological analyses were carried out by energy dispersive X-ray fluorescence spectroscopy (EDX), scanning electron microscopy, and the higher heating value determination. The results of the proximate analyses were 72.32% moisture, 78.47% volatile matter, 17.48% fixed carbon, and 4.05% ash. The results of the chemical analysis for extractables were 5.23% using organic solvent and 50.25% using hot water. The content determination were 17.13% lignin, 26.80% cellulose, and 37.17% hemicellulose. The results of the ultimate analysis were 43.59% C, 6.18% H, 3.46% N, and 37.22% O. The higher heating value experimentally obtained was 18.70 MJ/kg. Moreover, in the EDX analysis, Ca, P, K, and S were mainly found. It is recommendable to valorize the BSG through the xylitol, bioethanol or biogas production, because of its high moisture, hemicellulose and cellulose content.

Rapid depletion in fossil fuels, inflation in petroleum prices, and rising energy demand have forced towards alternative transport fuels. Among these alternative fuels, diesel-ethanol and diesel-biodiesel blends gain the most attention due to their quality characteristics and environmentally friendly nature. The viscosity and density of these biodiesel blends are slightly higher than diesel, which is a significant barrier to the commercialization of biodiesel. In this study, the density and viscosity of 30 different ternary biodiesel blends was investigated at 15 &deg, С and 40 &deg, С, respectively. Different density and viscosity models were developed and tested on biodiesel blends soured from different feedstock&rsquo, s including palm, coconut, soybean, mustard, and calophyllum oils. The prognostic ability and precisions of these developed models was assessed statistically using Absolute Percentage Error (APE) and Mean Absolute Percentage Error (MAPE). The MAPE of 0.045% and 0.085% for density model and 1.85%, 1.41%, 3.48% and 2.27%, 1.85%, 3.50% for viscosity models were obtained on % volume and % mass basis. These developed correlations are useful for ternary biodiesel blends where alcohols are the part of biodiesel blends. The modeled values of densities and viscosities of ternary blends were significantly comparable with the measured densities and viscosities, which are feasible to avoid the harm of vehicles&rsquo, operability.

Antioxidants are a wide group of chemical compounds characterized by high bioactivity. They affect human health by inhibiting the activity of reactive oxygen species. Thus, they limit their harmful effect and reduce the risk of many diseases, including cardiovascular diseases, cancers, and neurodegenerative diseases. Antioxidants are also widely used in the food industry. They prevent the occurrence of unfavourable changes in food products during storage. They inhibit fat oxidation and limit the loss of colour. For this reason, they are often added to meat products. Many diet components exhibit an antioxidative activity. A high antioxidative capacity is attributed to fruit, vegetables, spices, herbs, tea, and red wine. So far, the antioxidative properties of various plant materials have been tested. However, the antioxidative activity of some products has not been thoroughly investigated yet. To date, there have been only a few studies on the antioxidative activity of the pumpkin, including pumpkin seeds, flowers, and leaves, but not the pulp. The main focus of our experiment was to optimize the extraction so as to increase the antioxidative activity of the pumpkin pulp. Variable extraction conditions were used for this purpose, i.e., the type and concentration of the solvent, as well as the time and temperature of the process. In addition, the experiment involved a comparative analysis of the antioxidative potential of 14 pumpkin cultivars of the Cucurbita maxima species. The study showed considerable diversification of the antioxidative activity of different pumpkin cultivars.

Wine production is one of the most important agricultural activities around the world. The production of wine involves the use of a large number of valuable resources, such as water, fertilizers, and other organic products. Moreover, it produces a large amount of wastewater and organic waste that must be treated adequately to avoid contaminating the areas of production. The nature of the waste produced depends very closely on the specific vinification procedures, which also affect the physical–chemical properties of the residual material generated, whose characteristics determine its subsequent use and even condition the subsequent specific recovery circuit in which can be integrated.

Biowastes from the food industry can be applied as a usable material after appropriate treatment (i.e., agglomeration). Biowastes are materials that could have better properties if they are mixed. Brewery and oilseed wastes were compressed and evaluated by their quality and microstructure. This article presents the influence of food wastes&rsquo, type on their biodegradable composite properties. Rapeseed cake and brewer&rsquo, s threshing were used separately and mixed in three different proportions: 30:70, 50:50, 70:30. The data were obtained by mechanical testing on the Instron machine with different pressure forces of 30,000 N and 50,000 N. Strength and elasticity parameters, expansion after the test and in 24 h were estimated. The characteristics such as density, relaxation and compaction after the agglomeration process of biomass allows the selection of the best material and method for optimal composite quality. The results show an upward trend in composite density with decreasing content of brewery waste in a sample. Rapeseed cake can be considered as the material more susceptible to the compaction process. In addition to material properties and its lower density, the reason may be due to the granulometric composition of particles, density and particle size which was confirmed by SEM structure observations. Images of composites were analyzed on the basis of morphological plant tissue structures.

The most important advances in sustainability in the water industry are focused on the reuse of water treatment sludge. The Antaviliai Water Supply Plant, which is located in Lithuania, treats groundwater by removing iron and manganese from it. This technology does not produce water waste, as the iron sludge is used for recycling. In this study, iron sludge received from groundwater treatment is used to remove natural organic matter from river Neris water, which can be used as drinking water. Twelve doses (from 1 to 6 g/L and from 0.1 g/L to 0.9 g/L) of iron sludge powder, with acid and without it, were used. The most effective removal of organic compounds (55.51%) and reduction in water colour (53.12%) were observed when 0.3 g of iron sludge powder and 8 ml of 0.95% H2SO4 solution were added to the tested water. It was found that the use of a conventional coagulant (Al2(SO4)3*17H2O), with and without iron sludge powder, decreased the concentration of organic compounds and water colour from 2.8 to 28.2% compared with the use of a pure coagulant (Al2(SO4)3*17H2O) alone., This article belongs to the Special Issue Water-Energy Sustainable Urban Development

The article evaluates the effectiveness of the removal of organic pollutants&mdash, nitrogen and phosphorus&mdash, from household sewage in a hybrid bioreactor with a submerged fixed bed. The experiment was carried out in two exploitation variants that were both conducted in a laboratory model of the hybrid bioreactor: (I) cycles of 120 min of aeration and 60 min of no aeration with a constant sewage dosage, and (II) cycles 60 min of aeration and 60 min of no aeration, with a periodic sewage dosage in the no-aeration phase. The experiment was carried out on real sewage primarily treated in a septic tank. The amount of pollution removal was calculated and compared with the mandatory standards according to Polish law. Moreover, the susceptibility of the sewage to the biological treatment, nitrification, and denitrification activity was determined. The research shows a higher effectiveness for the 60/60 model in comparison to the 120/60 model. High operation efficiency was observed regarding the removal of organic pollution and nitrate nitrogen. The tested structure showed very low nitrification activity combined with intense denitrification. These processes were observed in the 60/60 variant. The structure was often overloaded with the nitrate nitrogen, which was considered to be the nitrification process inhibitor. It was suggested that phosphorus was also removed by the denitrifying bacteria.

Common wheat is currently the most widely grown cereal and its grains are mainly used to produce white bread. Contrary to plant seeds, the plant itself may be considered an agricultural waste which is used as an animal feed, soil fertilizer, or pelletized solid fuel to produce heat energy. While wheat straw is used widely in sustainable building construction, mostly as straw bales, the use of the thin dry husk around the grain, the wheat chaff, remained unexplored. An insulation panel made of a medium-density fiberboard (MDF) envelope and wooden studs was manufactured. The 150-mm gap between the MDFs was filled with dry wheat chaff. The thermal transmittance of the panel was determined under static and dynamic thermal conditions using a modified guarded hot box method. The results were compared to an insulation panel of the same construction that was filled with mineral wool. The thermal transmittance of wheat chaff under steady-state and dynamic conditions was 0.307 W m&minus, 2 K&minus, 1 and 0.298 W m&minus, 1, respectively. While in steady-state conditions the mineral wool outperforms the wheat chaff insulation, after a period of dynamic thermal loading, the ability of both insulations to resist heat-energy dissipation becomes similar. In conclusion, wheat chaff agrowaste seems to be a promising environmentally friendly alternative to artificial thermal insulation. Moreover, the determination of the thermal transmittance of bio-based materials with relatively high specific heat capacities under dynamic thermal loading, provides more accurate results, compared to steady-state conditions.

Like many other industries, the sugar and sugar-bioproduct industries are facing important sustainability issues and opportunities. The relatively low and fluctuating profit for sugar, surpluses of sugar, world-wide trend to produce alternative, renewable bio-based fuels and chemicals to those derived from petroleum and reduce greenhouse gases, water- and energy-intensive factories and refineries, and increased consumer demands for sustainably manufactured products are putting pressure on the industries to diversify for sustainability. Sugar crops, including sugar and energy cane (Saccharum officinarum), sugar and energy beets (Beta vulgaris), and sweet sorghum (Sorghum bicolor L. Moench), are excellent, renewable biomass feedstocks because of their availability, their being amongst the plants that give the highest yields of carbohydrates per hectare, and high sugar contents. While much research has been focused on conversion technologies for advanced biofuels and bioproducts, attention is now focused on developing sustainable supply chains of sugar feedstocks for the new, flexible biorefineries, with customers wanting maximum feedstock reliability and quality, while minimizing cost. All biomass from sugar crops are potential feedstocks. The cogeneration of bioelectricity from bagasse and leaf residues is being increasingly manufactured in more countries and, due to the high carbon content of bagasse and leaves, can also be converted into value-added products such as biochar. Sugar crops are superior feedstocks for the production of platform chemicals for the manufacture of a range of end-products, e.g., bioplastics, chemicals, and biomaterials. In several countries and regions, green sustainability criteria are now in place and have to be met to count against national biofuel targets. Processes to convert high-fiber sugar crop biomass into biofuel have been developed but there has only been limited commercialization at the large-scale.

Substantial progress has been made in algal technologies in past few decades. Initially, microalgae drew the attention of the scientific community as a renewable source of biofuels due to its high productivity over a short period of time and potential of significant lipid accumulation. As of now, a technological upsurge has elaborated its scope in phycoremediation of both organic and inorganic pollutants. The dual role of microalgae—i.e., phycoremediation coupled with energy production—is well established, however, commercially, algal biofuel production is not yet sustainable due to high energy inputs. Efforts are being made to make the algal biofuel economy through modification in the cultivation conditions, harvesting, and extraction of value added products. Recent studies have demonstrated algal biomass production with various types of wastewater and industrial effluents. Similarly, the recent advent of eco-friendly harvesting technologies—such as low-cost green coagulants, electrochemical harvesting, etc.—are energy efficient and economical. Contemporary improvement in efficient lipid extraction from biomass will make algal biodiesel economical. The absolute extraction of all the value added products from algal biomass, either whole cell or lipid extracted biomass, in a complete biorefinery approach will be more economical and eco-friendly.

This study analyzed the direct and indirect CO2 emissions of the energy-intensive basic metals industry, in particular steels, using the distributions of various energy sources, including coal/peat, oil, and electricity, from an input-output table. An analysis of five major steel producing countries indicated that direct CO2 emissions increased 1.4-fold and that indirect CO2 emissions increased by more than two-fold between 1995 and 2010. The elasticity of the CO2 emissions and the total energy costs indicated that Korea, Japan, and Germany are sensitive to energy sources from the electric power industry, whereas China and the US are more sensitive to energy sources pertaining to the coal and oil industry. Using the available forest area and photosynthesis, the potential neutralization ability of CO2 was estimated using the eco-CO2 index. The US yielded the highest CO2 neutralization ability of 66.1%, whereas Korea yielded a CO2 neutralization ability of 15%. Future trends of the 2030 eco-CO2 index revealed China and Korea will rapidly lose their neutralization ability resulting in a net negative neutralization ability if left unabated. The significant decline in the eco-CO2 index for the basic metals industry may be inhibited by utilizing bamboo wood charcoal for pulverized coal injection (PCI) in the steelmaking process.

This case study shows results of a calculation of carbon footprint (CFP) resulting from the production of nuts added value products for a large consumer market. Nuts consumption is increasing in the world and so is the consumer awareness of the environmental impact of goods, hence the calculation of greenhouse gas (GHG) emissions of food production is of growing importance for producers. Calculation of CO2eq emissions was performed for all stages of the production chain to the final retail point for flour, grains, paste, chocolate covered nuts and spreadable cream produced from almonds, pistachios and hazelnuts grown and transformed in Italy and for peanuts grown in Argentina and transformed in Italy. Data from literature was used to evaluate CFP of raw materials, emissions from transport and packing were calculated using existing models, while emissions deriving from transformation were calculated empirically by multiplying the power of production lines (electrical and/or thermal) by its productivity. All values were reported in kg of CO2 equivalent for each kg of packed product (net weight). Resulting values ranged between 1.2 g of CO2/kg for a 100 g bag of almond to 4.8 g of CO2/kg for the 100 g bag of chocolate covered almond. The calculation procedure can be well used for similar cases of large consumer food productions.

Evaluation of the sustainability of biomass pyrolysis requires a thorough assessment of the product yields and energy densities. With this purpose, a laboratory scale fixed bed reactor (FBR) was adapted from the standard Gray-King (GK) assay test on coal to conduct fixed bed pyrolysis experiments on agricultural and agro-industrial by-products. The present study provides results on the pyrolysis of two types of biomass: chipped olive tree trimmings (OT) and olive pomace (OP). Solid (char) and liquid (tar) product yields are reported. Mass yields are determined and compared with values obtained in similar works. Results indicate that char yield decreases from 49% (OT-db) and 50% (OP-db) at 325 °C to 26% (OT db) and 30% (OP-db) at 650 °C. Tar yield is almost constant (42%) at different reaction temperatures for OT, while it decreases slightly from 42% to 35% for OP. Energy density of the products at different peak temperatures is almost constant for OT (1.2), but slightly increases for OP (from a value of 1.3 to a value of 1.4).

Global warming and climate change are becoming a global concern. In this regard, international agreements and initiatives have been launched to accelerate the use of renewable energy and to mitigate greenhouse gas (GHG) emissions. Yemen is one of the countries signed on these agreements. However, Yemen is facing the problem that the structure of the power grid is fragile and the power shortage is serious. Accordingly, this paper aims to study the potential for renewable energy in Yemen and assess the technical and economic feasibility of hybrid energy systems. Firstly, this paper introduces the status and challenges of Yemen&rsquo, s electricity sector, the status of renewable energy, and the status of GHG emission. Secondly, this study proposes the method of optimizing different configurations of off-grid hybrid (solar/wind/diesel engine) energy systems for electrifying various consumers in Taiz province, Yemen under three scenarios of energy strategies. The objective function is to seek the most optimal hybrid energy system that achieves the least cost and most advantageous technical performance, while instigating the best economic scenario of energy strategies. Finally, Homer pro software is used for simulation, optimization, and sensitivity analysis of the designed energy systems. The results found the best economically feasible scenario, the hybrid PV/wind/diesel energy system, among the other scenarios. A photovoltaic (PV)/wind energy system achieved the best technical performances of 100% CO2 reduction, with a 54.82% reduction in the net present cost (NPC) and cost of energy (COE), while the hybrid energy system (PV/wind/diesel engine) achieved the best economic cost of 61.95% reduction in NPC and COE, with a 97.44% reduction of CO2 emission.

Air pollution is a common problem for many countries around the world in the process of industrialization as well as a challenge to sustainable development. This paper has selected Chengdu-Chongqing region of China as the research object, which suffers from severe air pollution and has been actively involved in air pollution control in recent years to achieve sustainable development. Based on the historical data of 16 cities in this region from January 2015 to November 2019 on six major air pollutants, this paper has first conducted evaluation on the monthly air quality of these cities within the research period by using Principal Component Analysis and the Technique for Order Preference by Similarity to an Ideal Solution. Based on that, this paper has adopted the Long Short-Term Memory neural network model in deep learning to forecast the monthly air quality of various cities from December 2019 to November 2020. The aims of this paper are to enrich existing literature on air pollution control, and provide a novel scientific tool for design and formulation of air pollution control policies by innovatively integrating commonly used evaluation models and deep learning forecast methods. According to the research results, in terms of historical evaluation, the air quality of cities in the Chengdu-Chongqing region was generally moving in the same trend in the research period, with distinct characteristics of cyclicity and convergence. Year- on-year speaking, the effectiveness of air pollution control in various cities has shown a visible improvement trend. For example, Ya&rsquo, an&rsquo, s lowest air quality evaluation score has improved from 0.3494 in 2015 to 0.4504 in 2019, Zigong&rsquo, s lowest air quality score has also risen from 0.4160 in 2015 to 0.6429 in 2019. Based on the above historical evaluation and deep learning forecast results, this paper has proposed relevant policy recommendations for air pollution control in the Chengdu-Chongqing region.

The main aim of this paper is to analyze the influence of service companies&rsquo, corporate social responsibility (CSR) actions on final customer&rsquo, s loyalty. A theoretical model of loyalty formation based on CSR was proposed and a sample of 1125 final customers of financial services in Spain was studied. Structural equation models were used to verify the hypothesized relationships. Based on the CSR theory oriented to stakeholders, this work justifies the direct and positive relationship between the perception of CSR actions in the shopping experience and customer trust. We also verified a positive indirect influence on loyalty. The services industry was chosen to conduct this research due to its own particularities (intangibility, inseparability, heterogeneity and perishability). As it is impossible to evaluate a service before its consumption, a high level of trust in the supplier will be necessary to motivate the purchase decision. We conclude that CSR becomes a key strategic asset for determining trust and loyalty among consumers. As major findings, we have verified the special importance of CSR in the services market. CSR improves customer trust in the service provider. Thus, this paper has significant managerial implications. Through CSR strategies, both the perception of the customer&rsquo, s purchasing experience and trust can be enhanced, resulting in more loyal customers. As a limitation, this research was carried out among financial services. Further research should test the model across different industries and countries in order to determine the generalizability and consistency of the findings of this study.

Innovation systems are increasingly oriented towards the solution of societal and environmental problems. Social entrepreneurship can be regarded as a market-based actor, inherently aimed at finding solutions for these problems. The development of technologically advanced social entrepreneurship represents an outcome of problem-oriented innovation systems, requiring a closer link between social and technological innovation. Nonetheless, the literature has not yet explored a key element of these innovation systems: the technology transfer processes, which may enable social entrepreneurial organizations to act as innovation actors leveraging on technology. This paper investigates the relationship between the technology transfer processes targeting social entrepreneurship and different models of problem-oriented innovation ecosystems. The paper relies on a multiple-case-study design, including two problem-oriented innovation ecosystems in the Italian context, namely, MIND and Torino Social Impact, which are technology transfer projects designed to target social entrepreneurship. Drawing from content analysis of interviews, documents and direct observations, the results stress that the different objectives and contents of technology transfer, coupled with different perceptions of the idiosyncratic features of social entrepreneurship compared to commercial entrepreneurship, fit different ecosystem models in terms of the participating actors, governance and primary orientation to social or economic value generation.