This work aims to systematically investigate the influence of process temperature, biomass-to-water ratio, and production scales (laboratory and pilot) on the chemical composition of aqueous and gaseous phases and mass production of chemicals by hydrothermal processing of Açaí (Euterpe oleraceae, Mart.) seeds. The hydrothermal carbonization was carried out at 175, 200, 225, and 250 °C at 2 °C/min and a biomass-to-water ratio of 1:10; at 250 °C at 2 °C/min and biomass-to-water ratios of 1:10, 1:15, and 1:20 in technical scale; and at 200, 225, and 250 °C at 2 °C/min and a biomass-to-water ratio of 1:10 in laboratory scale. The elemental composition (C, H, N, S) in the solid phase was determined to compute the HHV. The chemical composition of the aqueous phase was determined by GC and HPLC and the volumetric composition of the gaseous phase using an infrared gas analyzer. For the experiments in the pilot test scale with a constant biomass-to-water ratio of 1:10, the yields of solid, liqu... [more]

In this study, coffee waste (CW) and empty fruit bunches (EFB) were employed as precursors for the production of activated carbons by a chemical activation method. KOH, ZnCl2, and H3PO4 were used as activating agents along with their three mixing ratios of 1:0, 1:1, 1:3, w/w, and carbonization temperatures of 600 °C, 700 °C, and 800 °C were used to prepare these activated carbons. The highest yields of produced activated carbons were observed at 600 °C with a value of 45.20% for coffee waste and 48.20% for empty fruit bunch, with a 1:3 w/w (H3PO4) ratio. However, the maximum specific surface area was 3068 m2 g−1, and 2147 m2 g−1 obtained at 800 °C for coffee waste and empty fruit bunch activated carbons, respectively. The surface features of these products exhibited acute morphological changes, as were clearly noticed via SEM studies. Moreover, in the Van Krevelen diagram, it was also observed that both the H/C and O/C ratios were dramatically decreased to 0.0019 and 0.0759, and 0.0066... [more]

The influence of moisture content on substrate thermal conductivity at different temperatures was investigated for four different commercially available substrates for green roofs. In the unfrozen state, as moisture content increased, thermal conductivity increased linearly. In the phase transition zone between +5 and −10 °C, as temperature decreased, thermal conductivity increased sharply during the transition from water to ice. When the substrate was frozen, thermal conductivity varied exponentially with substrate moisture content prior to freezing. Power functions were found between thermal conductivity and temperature. Two equally sized, green roof test cells were constructed and tested to compare various roof configurations including a bare roof, varying media thickness for a green roof, and vegetation. The results show that compared with the bare roof, there is a 75% reduction in the interior temperature’s amplitude for the green roof with 150 mm thick substrate. When a sedum mat... [more]

Yeasts were isolated from four potential sources, sweet sorghum juice, sugar cane juice, grapes and rambutan. The 27 yeast isolates were tested for their ethanol tolerance (15% v/v of ethanol) and ethanol fermentation performance in a synthetic ethanol production medium (200 g/L of total sugar). Only five isolates, SCJ04KKU, SCJ07KKU, SCJ09KKU, SCJ14KKU and SSJ01KKU could tolerate 15% ethanol and produce ethanol at levels higher than 55 g/L. The ethanol production efficiency from sweet sorghum juice under high gravity (HG, 200 and 240 g/L of total sugar) and very high gravity (VHG, 280 g/L of total sugar) conditions of the five isolates was tested. Saccharomyces cerevisiae NP01 and S. cerevisiae ATCC4132 were used as reference strains. The results showed that the SSJ01KKU isolate gave the highest ethanol production efficiency under all conditions. Ethanol concentration (PE), yield (YP/S) and productivity (QP) values were 98.89 g/L, 0.50 and 1.18 g/L·h, respectively, with sugar consumpt... [more]

The paper presents the results of the pelletization (agglomeration) tests of post-harvest tobacco waste as a feedstock for fuel pellet production. The experiment was conducted on a prototype pelleting−briquetting device with a flat matrix. The influence of the tobacco waste moisture content (17, 21 and 25wt.%) and the rotational speed of the agglomerating rolls (120, 170 and 220 rpm) on the power demand and on the pellet’s kinetic durability and density were determined. It was found that the moisture content has a significant impact on the pellet’s density but slightly affects its kinetic durability. The obtained pellets were characterized by a high density above 1000 kg·m−3 and kinetic durability above 97%. In order to examine the exhaust composition, the obtained pellets were combusted in a 25 kW fixed great boiler. High amounts of CO, SOx, NO and HCl were obtained, which suggests that the selection of a different technology for tobacco waste pellet combustion should be made.

Sicily is characterized by rural buildings, Palmenti, destined to wine production, which are scattered along the countryside and part of the local historical heritage. There are different types of rural buildings, but all have in common the use of ancient and well-established bioclimatic techniques for wine conservation and aging. Most of them were built with the double function of living space for the owner and productive spaces for all the activities correlated to the cultivations. Indeed, many rural houses, destined to the wine production, are characterized by wineries and wine cellars (the first for the wine production, the second to store the wine for the aging process). The growing production of high-quality Sicilian wines, very appreciated all over the world, leads to upgrade the ancient Palmenti to seek optimal hygrothermal conditions and, therefore, to guarantee high performance of the produced and stored wines. The purpose of this study is to investigate how the retrofit meas... [more]

With the recent increase in biomass pellet consumption, the mechanical degradation of pellets during transport and handling has become more important. ISO standard 17831-1 is an accepted global standard that is commonly used amongst researchers and industries to determine the mechanical durability of pellets. However, the measured mechanical durability sometimes fails to match the certificate accompanying the shipment. In such cases, pellet length specifications are suspected to play a role. This paper studies the effect of pellet length on mechanical durability for various types of commercially produced biomass pellets. In addition, the effect of test conditions and torrefaction on the mechanical durability of biomass pellets has been investigated. To study the effect of pellet length, pellets were classified into three groups: shorter than 15 mm, 15 to 30 mm, and longer than 30 mm, and their length distributions were measured using an in-house image processing tool. Then, the mechani... [more]

Upgrading biomass waste streams can improve economics in wood industries by adding value to the process. This work considers use of a hydrothermal carbonization (HTC) process for the residual feedstock after lignin and hemicelluloses extraction. Batch experiments were performed at 200−240 °C temperatures and three hours residence time with an 8:1 biomass to water ratio for two feedstocks: Raw spruce and spruce after lignin extraction. The proximate analysis and heating value showed similar results for both feedstocks, indicating that the thermochemical conversion is not impacted by the removal of lignin and hemicelluloses; the pretreatment processing slightly increases the heating value of the treated feedstock, but the HTC conversion process produces a consistent upgrading trend for both the treated and untreated feedstocks. The energy yield was 9.7 percentage points higher for the treated wood on average across the range temperatures due to the higher mass yield in the treated experi... [more]

spp. are among the most suitable species for biomass production, even for the firewood derived from medium-rotation coppice (MRC). The general problem of wood is that it cannot be utilized immediately because of the high moisture content, which in the combustion process would reduce remarkably the yield of energy. In this context, outdoor storage of whole stems without branches (WS), outdoor storage of whole stems with branches (WSB), open shed storage of firewood logs in mesh bags (OSF), and outdoor firewood logs in mesh bags (ODF) of Eucalyptus spp woody biomass were compared in term of moisture and dry matter loss to evaluate the most convenient form of storing biomass deriving from a medium-rotation coppice. During the storage period, ODF showed higher moisture values than OSF, WSB, and WS, underlining that moisture reduction is related to local climatic conditions, pile size and permeability (compaction). However, at the end of the storage period, the four options reached a simila... [more]

The present study considers evaporative cooling and desiccant unit-based air-conditioning (AC) options for livestock AC application. In this regard, proposed systems are investigated by means of experiments and thermodynamic investigations. Air-conditioning requirements for animals are theoretically investigated and temperature-humidity index (THI) is estimated. A lab-scale heat mass exchanger based on the Maisotsenko-cycle evaporative cooling conception (MEC) is set up and its performance is evaluated at different ambient air conditions. In addition, a desiccant-based air-conditioning (DAC) unit is thermodynamically evaluated using a steady-state model available in the literature. The study focuses on the ambient conditions of Multan which is the 5th largest city of Pakistan and is assumed to be a typical hot city of southern Punjab. The study proposed three kinds of AC combination i.e., (i) stand-alone MEC, (ii) stand-alone desiccant AC, and (iii) M-cycle based desiccant AC systems.... [more]

Economies have begun to shift from linear to circular, adopting, among others, waste-to-energy approaches. Waste management is known to be a paramount challenge, and food waste (FW) in particular, has gained the interest of several actors due to its potential impacts and energy recovery opportunities. However, the selection of alternative valorization scenarios can pose several queries in certain contexts. This paper evaluates four FW valorization scenarios based on anaerobic digestion and composting, in comparison to landfilling, by applying a consistent decision-making framework through a combination of linear programming, Life Cycle Thinking (LCT), and Analytic Hierarchy Process (AHP). The evaluation was built upon a case study of five universities in Costa Rica and portrayed the trade-offs between environmental impacts and cost categories from the scenarios and their side flows. Results indicate that the landfill scenario entails higher Global Warming Potential and Fresh Water Eutr... [more]

The aim of this study was to compare the aromatic profile of plum spirits, obtained from the Požegača and Stanley varieties, as affected by different combinations of pre-distillation steps used in traditional and six modified production methods that are common in Serbian distilleries. Traditional plum spirits (produced from spontaneously fermented mashes of crushed plums with stones distilled after two months of storage) had the highest contents of ethyl acetate, benzaldehyde, and total acids, which resulted in the occurrence of an unpleasant solvent-like and stone-like odour and acidic taste. These sensory defects were overcome by the distillation of fermented mashes immediately after the completion of alcoholic fermentation. Depending on the combination of the pre-distillation steps, plum spirits from mashes distilled immediately after alcoholic fermentation were characterized by different aromatic profiles: closer to traditional (from spontaneously fermented crushed plums with/witho... [more]

Chinese tea has a long history, and the development level of tea mechanization in this country is in the leading position internationally. Equipment for the tea processing craft is one of the most widely used types in China; indispensable technology is used for high-quality tea in the relevant tea processing equipment. The performance of tea processing equipment is always a focus when it is being used. Meanwhile, research evaluating the performance of tea processing equipment has been rarely reported. Thus, it is important to find a methodology to evaluate the performance of equipment for the tea processing craft. In this paper, a new method of rough set theory, as well as a radar chart for quality evaluation of tea processed by different tea processing crafts, is created. Firstly, the important indexes of processed tea are presented, including moisture, tea polyphenols, free amino acids, caffeine, and vitamin C. Then, these indexes for nine different types of processed tea based on di... [more]

This empirical study assesses the effect of CO2 emissions, urbanization, energy consumption, and agriculture on Thailand’s economic growth using a dataset between 1970 and 2018. The ARDL and the frequency domain causality (FDC) approaches were applied to assess these interconnections. The outcome of the bounds test suggested a long-term association among the variables of investigation. The ARDL outcomes reveal that urbanization, agriculture, energy consumption, and CO2 emissions positively trigger Thailand’s economic growth. Additionally, the frequency domain causality test was used to detect a causal connection between the series. The main benefit of this technique is that it can detect a causal connection between series at different frequencies. To the understanding of the authors, this is the first study in the case of Thailand that will apply the FDC approach to capture the causal linkage between GDP and the regressors. The outcomes of the causality test suggested that CO2 emission... [more]

Food security (FS) is influenced by primarily financial but also sociodemographic factors. Identification of correlates of food insecurity (FI) is a crucial issue in the context of achieving sustainable development goals. The aims of the study were: (1) to recognize FI in the selected Central and Eastern European (CEE) countries, (2) to examine common socioeconomic and demographic characteristics for FI. The analysis used the set of eight-item FI indicators adopted by the Food and Agriculture Organization, applying the Gallup World Poll survey data from 2017 to 2019. Multinomial logistic regressions were used to examine FI at mild and moderate or severe levels compared with FS. Differences in the profiles of FI were observed in analyzed countries: Poland, Lithuania and Slovakia. Lithuanians experienced the lowest FS, and Slovaks the highest. The FI status was associated with education, gender, age, household composition and income. It was found that the impact of these factors was not... [more]

The negative impact of agricultural production on the environment is manifested, above all, in the emission of greenhouse gases (GHG). The goals of this study were to estimate methane and nitrous oxide emissions at the level of individual farms and indicate differences in emissions depending on the type of production, and to investigate dependencies between greenhouse gas emissions and economic indicators. Methane and nitrous oxide emissions were estimated at three types of farms in Poland, based on FADN data: field crops, milk, and mixed. Data were from 2004−2018. Statistical analysis confirmed the relationship between greenhouse gas emissions and economic performance. On milk farms, the value of methane and nitrous oxide emissions increased with increased net value added and farm income. Milk farms reached the highest land productivity and the highest level of income per 1 ha of farmland. On field crops farms, the relationship between net value added and farm income and methane and n... [more]

The calculation method commonly used in the industry takes into consideration mainly fuel consumption (excluding electricity) and the amount of removed moisture which is reflected in the unit MJ·(Mg·%)−1. This is not a scientific approach because the result will change if the basic moisture is different (drying from 21% to 18% will consume less energy than drying from 18% to 15%). This paper aims to compare the energy consumption of two industrial continuous flow grain dryers powered by LPG and hard coal based on a comprehensive approach to energy efficiency calculation enriched with electricity consumption, flow measurements, and control of grain moisture. It could be useful for manufacturers who could use this method to generate more reliable data in their product datasheets, and it could also be legally regulated as an appropriate tool for calculating the energy consumption of agricultural grain dryers. According to the approach presented in this paper, the S428.CS construction powe... [more]

Microwave torrefaction of oat hull was conducted to enhance its physicochemical properties. A bench-top reactor with an internal stirrer was used for oat hull pretreatment at temperatures of 225 °C, 255 °C, and 285 °C, and residence times of 3, 6, and 9 min, respectively. Results showed that a high temperature level at 3 min residence time or severe torrefaction increased calorific values by up to 35% of its original value, while decreasing mass yield down to 60.77%. Severe torrefaction further decreased moisture absorption, moisture content, and grinding energy consumption but decreased energy yield and bulk density. Residence time had no significant effect on biomass physicochemical changes; however, production cost may be significantly increased by longer residence times. It was also concluded that increased microwave power levels from 400 to 650 W decreased energy consumption by shortening processing times, resulting in a positive economic impact of the process. Moderate and severe... [more]

In recent studies, various reports reveal that stubble burning of crop residues in India generates nearly 150 million tons of carbon dioxide (CO2), more than 9 million tons of carbon monoxide (CO), a quarter-million tons of sulphur oxides (SOX), 1 million tons of particulate matter and more than half a million tons of black carbon. These contribute directly to environmental pollution, as well as the haze in the Indian capital, New Delhi, and the diminishing glaciers of the Himalayas. Although stubble burning crop residue is a crime under Section 188 of the Indian Penal Code (IPC) and the Air and Pollution Control Act (APCA) of 1981, a lack of implementation of these government acts has been witnessed across the country. Instead of burning, crop residues can be utilized in various alternative ways, including use as cattle feed, compost with manure, rural roofing, bioenergy, beverage production, packaging materials, wood, paper, and bioethanol, etc. This review article aims to present th... [more]

Globally, millions of people suffer from poverty. This paper discusses the problem of poverty especially in relation to food waste. The prevention of food waste can also contribute to global poverty reduction, and the reduction of food waste is a tool for sustainable growth and competitiveness. At present, the number of people at risk of poverty and the amount of food waste are increasing at unsustainable rates. An integrated and efficient tool for the management of food, energy, and water (FEW) resources to improve FEW security via an interdisciplinary approach could help address several of the most significant global challenges, such as climate change, and economic, environmental, and social security. The aim of this study was to examine the relationship between the existence of poverty and the treatment of food for sustainable growth. The analysis focused on the EU countries and the main data source was the Eurostat database. Households generally create the largest proportion of foo... [more]

In this study, the densification of three agriculture waste biomasses (corn cobs, cotton stalks, and sunflower) is investigated using the torrefaction technique. The samples were pyrolyzed under mild temperature conditions (200−320 °C) and at different residence times (10 min−60 min). The thermal properties of the obtained bio-char samples were analyzed via thermo-gravimetric analysis (TGA). Compositional analysis of the torrefied samples was also carried out to determine the presence of hemicellulose, cellulose, and lignin contents. According to the results of this study, optimum temperature conditions were found to be 260 °C−300 °C along with a residence time of 20 min−30 min. Based on the composition analysis, it was found that biochar contains more lignin and celluloses and lower hemicellulose contents than do the original samples. The removal of volatile hemicelluloses broke the interlocking of biomass building blocks, rendering biochar brittle, grindable, and less reactive. The r... [more]

This paper aims to reveal the causal relationship between energy prices and food prices and whether this relationship is similar in the food sub-groups forming the food price index used. As food prices more than doubled during the 2008 economic crisis, this relationship has received considerable attention from researchers. Many researches have been conducted to determine the causes and consequences of the 2008 food price crisis. Researches are mainly focused on crude oil and bio-energy in terms of “energy”. This research is not only differentiated by the data used but also by the methodology employed. The study attempts to add new findings to the empirical food price literature by utilizing relatively newly developed methods, namely Toda−Yamamoto causality, Fourier Toda−Yamamoto causality, and spectral BC causality tests. The spectral BC causality test clearly reveals that there is bidirectional causality between the energy price index and food price indexes (grains, other food, and oi... [more]

The aim of this study was to identify and assess the factors influencing the increase in the financial energy of a farm through the use of external capital, taking into account the farmer’s and farm characteristics. For its implementation, a logistic regression model and a classification-regression tree analysis (CRT) were used. The study was conducted on a group of farms in Central Pomerania (Poland) participating in the system of collecting and using data from farms (Farm Accountancy Data Network—FADN). Data on 348 farms were used for the analyses, obtained through a survey conducted in 2020 with the use of a questionnaire. Based on the analysis of the research results presented in the literature to date, it was established that the use of external capital in a farm as a factor increasing financial energy is determined, on the one hand, by the socio-demographic characteristics of the farmer and the characteristics of the farm, and on the other hand, by the availability of external fi... [more]

This research looked at the state of soils faced with urbanization processes in the Arctic region of the Yamal-Nenets Autonomous District (YANAO). Soils recently used in agriculture, which are now included in the infrastructure of the cities of Salekhard, Labytnangi, Kharsaim, and Aksarka in the form of various parks and public gardens were studied. Morphological, physico-chemical, and agrochemical studies of selected soils were conducted. Significant differences in fertility parameters between urbanized abandoned agricultural soils and mature soils of the region were revealed. The quality of soil resources was also evaluated in terms of their ecotoxicology condition, namely, the concentrations of trace metals in soils were determined and their current condition was assessed using calculations of various individual and complex soil quality indices.

In many countries, energy security is treated as a priority for the coming decades, and at the same time energy production from the vast majority conventional energy sources does not meet environmental protection criteria. Hence, the need to use renewable energy sources (RES), which can largely satisfy energy needs. The aim of the study was to identify possibilities of creating autonomous energy regions (ARE) in Poland, based on renewable energy sources. Attention was paid to the role and significance of the potential of rural areas in this respect, taking into account the possibilities of increasing energy production from these sources in individual regions of Poland. The research was conducted on a regional level (division into voivodships) and on a local level (division into powiats, which form voivodships). When assessing the potential for constructing ARE based on RES, the following energy sources were taken into account: water, wind, sun, biogas and biomass. It was found that the... [more]