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This study investigates the combustion of agricultural biomass rich in alkali elements in the fluidized bed. The experiments were performed with smashed corn cob in a 500 kW fluidized bed combustor which was designed for work under low bed temperatures (650–700 °C). During the experiments, the formed compounds from corn cob combustion were measured by sampling particulate matter, and mineral compositions were determined. Also, the temperature profile of the FBC was established. It was determined that the emissions of K and Na elements from the FBC increased from 4 to 7.3% and from 1.69 to 3%, respectively, changing the bed temperature from 650 to 700 °C. Though alkali emissions are reduced at a 650 °C bed temperature, CO emissions are higher by about 50% compared to the case of 700 °C. The addition of 3% of dolomite reduced the pollutant emissions and alkali emissions as well. Potassium content decreased by about 1% and 4%, respectively, at the bed temperatures of 650 °C and 700 °C. The NOx emissions were less than 300 mg/m3 and did not exceed the limit for medium plants regarding DIRECTIVE (EU) 2015/2193. During extended experiments lasting 8 h, no agglomeration of the fluidized bed was observed. Moreover, the proposed configuration of the FBC and its operational parameters prove suitable for facilitating the efficient combustion of agricultural biomass. [ABSTRACT FROM AUTHOR]

Contamination of shooting range soil with trace metal(loid)s, especially Pb, is an important issue due to its potential environmental hazards. The aim of the study was to evaluate the bioavailability and toxicity of Sb, Fe, and Ni to lettuce (Lactuca sativa L.) grown in highly contaminated soil (Pb 0.4—55 g kg−1, Sb < 0.5 g kg−1) of a civilian shooting range. Lettuce growth was negatively affected, especially of plants grown in the most highly contaminated soil, which was near the target lines, where roots accumulated Pb up to 40 g kg−1 (max 56 g kg−1), 10 times higher than in the shoots. Sb, Fe, and Ni were also accumulated in the roots, but their translocation to the shoots was low. [ABSTRACT FROM AUTHOR]

Shooting range soil is one of the most heavily contaminated sites in the world with heavy metals from shooting activities. The aim of the study was to evaluate remediation efficiency of contaminated shooting range soil using three plant species – Festuca arundinacea Schreb., Trifolium pratense L., and Medicago sativa L. assessing the impact of contamination on the development of plant species and the capacity of plants to accumulate potentially toxic elements from polluted soil. The field study was conducted in a Lithuanian civilian shooting range operating 65 years where lead (Pb) concentration in the shooting range soil was extremely high – 17,890 mg kg−1 and the elevated levels of antimony (Sb) was found in soil of berm. F. arundinacea had the highest biomass. The shoot height of all species grown in the contaminated shooting range soil was significantly lower than that of those grown in the uncontaminated soil. The shoot height of M. sativa and T. pratense was 30% lower compared to the control group, while the height reduction of F. arundinacea was only 10%. The same trend of the effect of contaminated soil on root length was observed - the roots were statistically significantly shorter than the control, while the mean root length of F. arundinacea did not differ from the control plants. The content of photosynthetic pigments in all three species tested was also significantly lower as that of the control plants due to contaminated shooting range soil. Shoots of T. pratense plants grown in the shooting range soil accumulated 10 times higher concentrations of Pb and 3 times higher concentrations of Sb in M. sativa compared to the control. Among all studied plants, F. arundinacea was the plant capable of accumulating significantly higher amounts of Pb, nickel (Ni) and Sb in roots than in shoots. The roots of all treated plants accumulated significantly higher concentrations of Pb compared to the control. The highest concentrations of Pb were determined in the shoots of F. arundinacea and T. pratense. Only the roots of M. sativa and F. arundinacea , accumulated higher concentrations of Ni and Sb, compared to controls. The significantly higher bioconcentration factor of Pb (BCF Pb) was determined in F. arundinacea but it still was lower than 1.0. The Pb accumulation capacity of the different plant species was in the following order: F. arundinacea > T. pratense > M. sativa showing phytostabilization potential of plants. T. pratense had the highest translocation factor (TF) values, being able to translocate a high proportion of Pb and Sb from roots to shoots, while F. arundinacea had the lowest efficiency. • Contaminated shooting range soil is a long-term source of Pb and Sb. • Determination of Pb, Sb and Ni plant uptake by three plant species. • Roots growth was impaired with the highest trace element accumulation in roots. • The highest phytoremediation efficiency was observed in T. pratense. • Higher accumulation of Pb in roots of the plants indicate of their phytostabilising properties. [ABSTRACT FROM AUTHOR]

Contamination at shooting ranges is a growing concern due to the accumulation of potentially toxic elements in the soil. The aim of the study was to determine the level of soil contamination in different types of Lithuanian shooting ranges (clay-target, practical, small-bore) and assess the potential ecological risks. Soil samples were taken in two soil layer depths (0–10 cm and 10–30 cm) and locations (range floor and berm/target line) of different types of shooting ranges. The soils of the practical and small-bore shooting ranges were neutral, clay target – slightly alkaline. The soil of the clay-target firing range floor had a significantly lower organic matter, than small-bore and practical firing ranges. Lead contamination was significantly higher in the floor and berm surface soil and subsoil (about 1000 mg kg−1 and 360–527 mg kg−1, respectively) of the practice range compared to the others and controls. The Cd concentrations in the surface soil of the practical range and the small-bore firing ranges and in the soil of the berm were considerably higher than in the soil of the clay target. There was a significant negative correlation between soil pH and Pb and Cd concentrations. Pb content was positively correlated with organic matter content. The soils of the practical range floor and berm indicated high ecological risk. The research showed that heavy metal contamination is specific in different types of shooting ranges, therefore various management practices should be applied to prevent pollution in particular shooting range. [ABSTRACT FROM AUTHOR]

Complex effectiveness and emission studies were carried out for heating boilers of low heat output, fired with wood fuel. The studies were completed in a series of stages. The first step was directed at the investigation of properties of currently used biofuel made of biomass and potentially perspective biofuel made of agromass in order to determine specific properties and how fuel should be prepared so that it could be efficiently burned in heating boilers. The second stage included numerical and experimental studies of various combustion chambers of heating boilers and air/flue gas canals in order to improve air/combustion product mixing and assuring proper combustion products' presence time in the hot zone and their temperature. During the last stage, the distribution of the particulate matter concentration in combustion products depending on their size and reduction methods of the concentration were analyzed. [ABSTRACT FROM AUTHOR]

Wood chips and logging residues currently comprise the largest share of biomass fuels used for heat generation in district heating plants and are provided by a variety of suppliers. Ash and moisture contents, as well as the calorific value, may vary considerably depending on the composition of the fuel, seasonality, location, and other factors. This paper provides the summarized results of the main characteristics of wood chip moisture and ash content and calorific value, experimentally tested for a significant range of samples. Chip samples were collected from two district heating companies and tested for a significant range of samples. Chip samples were collected from two district heating companies and tested for a 3-year period. The data on fuel chip prices were taken from the electronic wood chip trading platform. The tests were performed using standard express methods, where two sub-samples were taken and analyzed from every chip sample. It was determined that the moisture content of the wood chips varied from 35% to 45%, the calorific value from 18.4 to 19.6 MJ/kg, and the ash content from 0.5% to 4.5%. The calculated relative expanded uncertainty of the moisture content measurement was ±2.1%, of calorific value—±1.5%, and of ash—±1.0%. The repeatability of the results was estimated as the pooled standard deviation. [ABSTRACT FROM AUTHOR]

The aim of this study was to further increase the amount of straw that can be used to produce solid biofuels, as currently only about 130–140 thousand of the 3 million tonnes of straw collected annually in Lithuania are used for solid biofuel production. Therefore, the use of buckwheat hulls as an additive in solid biofuel production was investigated. Mixtures of wheat straw and buckwheat hulls were used for this research, with an increase in buckwheat hulls from 25% to 75% of the total weight of the mixture. Results of the analysis of the chemical composition, moisture, ash, and volatile matter content of the mixtures, as well as their ash properties, were compared with the corresponding results obtained with pure buckwheat hulls, wheat straw, and wood chips. It is observed an increase in all ash melting temperatures by increasing the portion of buckwheat hulls in the mixture. Additionally, the ash shrinkage starting temperature was shown to increase as the total content of buckwheat hulls also increased in the mixture. This increase ranged from 90 °C to 210 °C. Furthermore, the Cl concentration in fuel mixtures and the corrosion risk of equipment are accordingly reduced by using buckwheat hulls, as an addition that does not contain Cl. [ABSTRACT FROM AUTHOR]

• Hemp biomass production on clay loam soil on average latitudes. • Heavy metal, alkaline earth-alkali metals and non metals distribution in hemp parts. • Bioconcentration factor impact to soil remediation of heavy metals. • Alkaline earth-alkaline metals and non metals impact to slagging process in combustion. Industrial hemp (Cannabis sativa L.) has emerged as a potential multipiurpose crop: fibre crop, energy crop, and phytoextractor of pollutants from the soil. However, the multipurpise grwoth of hemp was restricted as its cultivation in EU was legalized only in the past two decades. Most scientific researches of sewage sludge (SS) describe it at relatively low application levels for cultivation of different crops. Such lack of information requires a wide range of practices for fertilizing hemp with high level of sewage sludge or sewage sludge char (SSCh) doses. At this moment there are no guidelines for sewage sludge char fertilization of energetic plants, depending on soil type. The aim of the study was to analyze and compare SS and SSCh soil application effect on industrial hemp (Cannabis sativa L.) growth performance, and heavy metals accumulation to determine optimum SS or SSCh application rates for the growth of hemp. The experimental design consisted of four treatments: 1–25; 2–50; 3–100; 4–200 of sewage sludge and sewage sludge char Mg ha−1, and control soil (clay loam). It was determined that hemp ability to accumulate heavy metals depending on fertilisation intensity of sewage sludge and sewage sludge char decreased in all parts. Heavy metal distribution of hemp was selective; therefore their contents were decreasing in the following order: roots > stems > leaves. The study has confirmed the nutritional value of SS and SSCh. The potential of using the sewage sludge and its char as a source of organic matter for improvement of clay loam soil and a reasonable production of bioenergy crop like hemp without the use of inorganic fertilizers was shown. [ABSTRACT FROM AUTHOR]

The recovery of short fibre and epoxy resin from glass fibre-reinforced epoxy resin composites (GFRP) poses a major challenge to the waste recycling sector. These challenges grow when GFRP is mixed with other additives such as carbon nanotubes (CNTs), graphene (GA), and carbon black particles (CB). However, the complexity in terms of activation energy (Ea) can be decreased through involvement of ZSM-5 zeolite catalyst in the pyrolysis process to convert resin component into chemical and energy products. Within this context, this research aims to study the catalytic pyrolysis of GFRP mixed with three fillers with different structures and dimensions (nanofillers "CNTs, GA" and micro-filler "CB") over zeolite catalyst, where these fillers can be used alongside zeolite particles as hybrid catalysts during the thermal conversion process. The GFRP mixed with different filler panels were prepared in the laboratory using a vacuum-assisted resin transfer method, then they were ground to fine particles and mixed with 200 mass% of ZSM-5 catalyst to prepare them for thermochemical experiments using thermogravimetry (TGA) at 5–30 °C min−1. The effect of various hybrids on the formulated pyrolysis vapours was studied using TG-FTIR and GC–Ms measurements. The kinetic Ea of each batch was studied using three linear isoconversional methods and two nonlinear isoconversional methods to investigate their effect on the decomposition mechanism. Besides, their thermochemical decomposition curves (TGA-DTG) were numerically simulated using DAEM and IPR models. The FTIR and GC analyses revealed that the hybrid catalyst had enhanced formation of aliphatic compounds and phenol compound in case of nanofillers up to 54% (CNTs) and 57% (GA), hence improving them by 17 and 54%, respectively. Meanwhile, the kinetic analysis showed that hybrid catalysts can contribute to a significant reduction in Ea up to 158 kJ mol−1 (CNTs), 127 kJ mol−1 (GA), and 124 kJ mol−1 (CB), which means that the decomposition of GFRP, becomes easier and requires less energy. Also, the simulated and experimental results showed big consistency in terms of smaller reaction complexity and higher generation of volatile compounds with increasing heating rates and addition of hybrid catalysts. [ABSTRACT FROM AUTHOR]

Changes in soil moisture content accompanying ongoing climate change are expected to affect plant growth and contaminants behaviour in the soil. The study was aimed at investigating soil water content impact on the energy crop oilseed rape (Brassica napus L.) efficiency to remediate Cd contaminated soil (1–250 mg kg−1). B. napus growth, Cd accumulation and removal efficiency were evaluated under optimal, reduced and elevated soil water content (SWC). B. napus showed good tolerance to Cd contamination and ability to phytoextract Cd from the soil. Cd accumulation in oilseed rape increased with Cd soil concentration, whereas removal efficiency was regulated by rape growth and Cd soil concentrations. B. napus has demonstrated good efficiency to cope with low and moderate Cd pollution (with tolerance index TI > 0.69), while high Cd soil pollution had a highly significant adverse impact on plant growth (growth was reduced up to 90%) resulting in low Cd removal efficiency. SWC governed plant growth, Cd accumulation and removal from the soil. Oilseed rapes grown under elevated SWC were of higher biomass (18%) compared to those grown under reduced SWC though the detrimental effect of Cd was more severe at elevated SWC. Reduced SWC led to decreased Cd uptake, conversely elevated SWC promoted Cd uptake. The optimal SWC ensures the highest Cd removal efficiency, whereas soil water deficit or excess restricts B. napus potential to remove Cd from the soil and prolongs remediation. • B. napus had a good tolerance to Cd and the ability to phytoextract Cd from soil. • Non optimal SWC restricts Cd phytoremediation potential and prolongs the process. • The optimal SWC ensures the most efficient Cd removal from the soil. [ABSTRACT FROM AUTHOR]

The remarkable properties of polysulfone (PSF) membranes have contributed to their use in many ultrafiltration applications. Meanwhile, this huge usage of PSF films and its short service life have generated a huge amount of waste PSF films that need to be managed carefully. Within this framework, this is the first research specifically developed to valorize the end-of-life of PSF membranes and convert them into high-value chemical and energy products using pyrolysis treatment. The treatment was performed using a thermogravimetric analyzer (TGA), while the structure and abundance of the phenol and benzoic acid compounds in the generated vapor were determined using Fourier-transform infrared (FTIR) spectroscopy and Gas chromatography-mass spectrometry (GC-MS). Thermogravimetric recorded data at different conditions (5–30°C/min) was subjected to linear and nonlinear models including KAS, FWO, Friedman, Vyazovkin, and Cai to assess the pyrolytic kinetic behavior of PSF films. The films showed higher content of volatile matter (57%), lower NOx emissions (0.321%), and a little bit more SOX emission (6.909%). The GC-MS showed that the pyrolytic gaseous products are rich in phenol (24.3%) and benzoic acid (52.4%) compounds and the highest abundance was achieved at 30°C/min. Whereas activation energies were estimated in the range of 193–240 kJ/mol based on linear kinetic criteria versus 161–163 kJ/mol in the case of nonlinear models, where R2 values (>0.91) indicated perfection. Also, distributed activation energy and independent parallel reaction kinetic models showed a good fit with the TGA-DTG experimental data with the minimum deviation. The study confirmed the potential of pyrolysis treatment in converting wasted PSF films into a new source for the recovery of phenolic and benzoic acid. [ABSTRACT FROM AUTHOR]

Global climate change leads to increasing frequency of droughts, threatening the productivity and quality of forage plants. Therefore, this glasshouse experiment was conducted to investigate the effects of reoccurring droughts on productivity and nutritive value of alfalfa and hybrid fescue plants. Starting from 63 days after sowing, seedlings of plants were exposed to double drought‐recovery treatments, each separate period lasting for 1 week. At the end of each treatment, growth of above‐ and below‐ground dry weight, lipid peroxidation, total antioxidative capacity, content of polyphenols, soluble and insoluble carbohydrates and proteins, as well as elemental composition of shoots were investigated. The findings confirmed our hypothesis, as growth of both plant species were mostly insignificantly affected by subsequent drought events. Whereas effect on leave redox homeostasis and plant nutritive value was much stronger, highly depending on both plant species and the order of stress event. We found significant drought‐induced increase in the content of water‐soluble carbohydrates (WSCs), starch, soluble and insoluble proteins, and polyphenols. Water shortage tended to decrease and increase the content of most macro‐ and microelements in alfalfa and fescue, respectively. These effects were reversed by re‐watering with several exceptions, such as constant reduction of Ca content in alfalfa. To conclude, alfalfa was found to be more sensitive than fescue to the first drought, but able to recover after both stress events. The second drought‐initiated prolonged accumulation of WSC implies a shift in plants metabolism towards increased resistance and herewith nutritive value with respect to soluble sugars. [ABSTRACT FROM AUTHOR]

Sewage sludge reuse in agriculture is increasing, however it can be an important route for contaminants to enter the environment. The aim of this study was to evaluate earthworm Eisenia fetida capability to reduce heavy metal content in the sewage sludge (SS) amended soil and increase soil fertility in terms of soil nutrients content. Adult earthworms were introduced into aged SS amended soil (0–200 Mg ha-1) and left for 65 days. Earthworms have stabilized soil pH and accelerated organic matter mineralization. The concentrations of most heavy metals during the vermiremediation sharply decreased, K and Mg decreased to a moderate extent, whereas Ca content has increased. The highest removal efficiency was detected for Ni, Co and Mn (> 80%), bioconcentration factors were as follows Zn > Co > Cu > Ni > Mn > Cr. The content of major nutrients (S, P) was substantially higher compared to the initial values. The most efficient remediation and soil quality improvement was achieved under the doses of 25–50 Mg ha-1. Higher (≥ 100 Mg ha-1) doses might restrict this technique application because of earthworm mortality and retarded growth. Overall, the study shows that vermiremediation might be a sustainable technique for ecological stabilization of SS amended soil and converting to usable for agricultural needs. [Display omitted] • Earthworms reduced toxic metals soil content and increased soil fertility. • Highest vermiremediation efficiency was in soils of low-moderate SS fertilization. • Vermiremediation is limited under high SS load due to impaired earthworm performance. [ABSTRACT FROM AUTHOR]

Sewage sludge reuse in agriculture is increasing, however it can be an important route for contaminants to enter the environment. The aim of this study was to evaluate earthworm Eisenia fetida capability to reduce heavy metal content in the sewage sludge (SS) amended soil and increase soil fertility in terms of soil nutrients content. Adult earthworms were introduced into aged SS amended soil (0–200 Mg ha-1) and left for 65 days. Earthworms have stabilized soil pH and accelerated organic matter mineralization. The concentrations of most heavy metals during the vermiremediation sharply decreased, K and Mg decreased to a moderate extent, whereas Ca content has increased. The highest removal efficiency was detected for Ni, Co and Mn (> 80%), bioconcentration factors were as follows Zn > Co > Cu > Ni > Mn > Cr. The content of major nutrients (S, P) was substantially higher compared to the initial values. The most efficient remediation and soil quality improvement was achieved under the doses of 25–50 Mg ha-1. Higher (≥ 100 Mg ha-1) doses might restrict this technique application because of earthworm mortality and retarded growth. Overall, the study shows that vermiremediation might be a sustainable technique for ecological stabilization of SS amended soil and converting to usable for agricultural needs. [Display omitted] • Earthworms reduced toxic metals soil content and increased soil fertility. • Highest vermiremediation efficiency was in soils of low-moderate SS fertilization. • Vermiremediation is limited under high SS load due to impaired earthworm performance. [ABSTRACT FROM AUTHOR]

Intensity and frequency of heat waves (HW) accompanied by drought are increasing, however, still little is known about its effect on forage plants. A pot experiment was carried out in growth chambers in order to elucidate the multiple response of forage rape to combined HW and drought (HD) under current and elevated CO2 (HD + CO2). Forage rape was proved to be relatively HD‐resistant plant, with no significant and long‐term effects on shoot growth and photosynthetic performance, and effective stimulation of antioxidative system, especially in the case of HD + CO2 exposure. Activities of enzymes of ascorbate–glutathione cycle were further stimulated by elevated CO2 even after the termination of HD treatment. Nutritive value of forage rape was also positively affected, as was shown by elevated content of water‐soluble carbohydrates after exposure and starch after the period of recovery (up to 80% and 92%, respectively). Concentrations of most macro‐ and microelements were increased, and stabilized higher or equalized to control level after the period of recovery in a similar pattern for HD and HD + CO2 exposure. However, content of Ca was reduced and remained significantly lower (~20%). One of the most important negative and lagged HD effects was reduction of dry root biomass (~30%), most possibly induced by accumulation of non‐structural carbohydrates in shoot and was not mitigated by elevated CO2. To conclude, forage rape was proved to be a promising forage crop for the future climate with increased frequency of HWs; however, a special attention should be paid to the lagged effects, such as inhibition of root growth. [ABSTRACT FROM AUTHOR]

Olive mill wastewater (OMWW) management is recognized as the major defy that olive oil industry is facing. Recently, we have established an eco-friendly strategy for the OMWW conversion into irrigation water sources, green biofuels and biofertilizers. This work is a part of a series of papers detailing the different steps established in this environmental friendly strategy for OMWW management. It deals with the bio-oil production and characterization during the pyrolysis of OMWW impregnated on olive pomace (OP) in a pyrolyzer pilot. Results show a bio-oil production yield of 36 wt% during the pyrolysis test. This yield could be attributed to the recovery of organic compounds from OMWW through OP impregnation and their conversion to bio-oil. The bio-oil properties show that viscosity and flash point values could reach the European standards. However, the lower heating values (26 MJ/kg) and the acidic character limit its direct use. These values are attributed to the higher water and oxygen contents. The GC/MS analysis confirms these properties showing the presence of phenolic molecules and long chain organic acids. Therefore, OMWW impregnation on OP and pyrolysis could be considered as a promising issue for bio-oil production. However, this bio-oil requires an upgrading step for a better valorization. • A strategy for olive mill wastes recovery is established using pyrolysis technique. • A bio-oil production yield of 36% confirms the OMWW organic matter valorization. • Bio-oil viscosity and flash point properties could reach biofuels Standards. • Bio-oil contains many components as phenolic molecules and long chain organic acids. • Oxygen and water contents, acidic pH require improvement before bio-oil direct use. [ABSTRACT FROM AUTHOR]

Due to the increasing demand for glass fibre-reinforced epoxy resin composites (GFRC), huge amounts of GFRC waste are produced annually in different sizes and shapes, which may affect its thermal and chemical decomposition using pyrolysis technology. In this context, this research aims to study the effect of mechanical pre-treatment on the pyrolysis behaviour of GFRC and its pyrolysis kinetic. The experiments were started with the fabrication of GFRC panels using the vacuum-assisted resin transfer method followed by crushing the prepared panels using ball milling, thus preparing the milled GFRC with uniform shape and size. The elemental, proximate, and morphology properties of the panels and milled GFRC were studied. The thermal and chemical decomposition of the milled GFRC was studied using thermogravimetric coupled with Fourier-transform infrared spectroscopy (TG-FTIR) at different heating rates. Meanwhile, the volatile products were examined using TG coupled with gas chromatography–mass spectrometry (GC-MS). The TG-FTIR and TG-GC-MS experiments were performed separately. Linear (Kissinger–Akahira–Sunose (KAS), Flynn–Wall–Ozawa (FWO), and Friedman) and nonlinear (Vyazovkin and Cai) isoconversional methods were used to determine the pyrolysis kinetic of the milled GFRC based on thermogravimetry and differential thermal gravimetry (TG/DTG). In addition, the TG/DTG data of the milled GFRC were fitting using the distributed activation energy model and the independent parallel reactions kinetic model. The TG results showed that GFRC can decompose in three stages, and the main decomposition is located in the range 256–500 °C. On the other hand, aromatic benzene and a C-H bond were the major functional groups in the released volatile components in FTIR spectra, while phenol (27%), phenol,4-(1-methylethyl) (40%), and p-isopropenylphenol (34%) were the major compounds in GC-MS analysis. Whereas, the kinetic results showed that both isoconversional methods can be used to determine activation energies, which were estimated 165 KJ/mol (KAS), 193 KJ/mol (FWO), 180 KJ/mol (Friedman), 177 KJ/mol (Vyazovkin), and 174 KJ/mol (Cai). [ABSTRACT FROM AUTHOR]

Metallised food packaging plastics waste (MFPW) is the most complex fraction of plastic waste ever. Pyrolysis treatment is one of the most promising technologies that could be used to convert the plastic fraction of MFPW into energy products and to recover aluminum fraction mixed with char. Within this frame, this research aims to study the volatile products released from pyrolysis of MFPW and their kinetics by using the TG-FTIR/GC–MS system. The experiments were performed on six different types of MFPW (potato chips, chocolate, bakery, coffee, and biscuits) and its mixture. The developed strategy started with analysis of the selected MFPW samples and the proximate analysis showed that the samples were rich with volatile matter content (till 99.5 wt%). In parallel, DMCHA dissolution treatment was used for preliminary experiments to determine the total number and types of plastic layers in MFPW confined to EVA, PET, and LDPE. Afterwards, the TG-FTIR system was used to investigate the thermal and chemical degradation of the MFPW samples up to 900 °C at different heating rates (5-30˚C/min), while the GC/MS system was used to study the volatile products generated from MFPW samples at the maximum decomposition temperatures (467-485˚C). Finally, the model-free methods (Kissinger, Kissinger–Akahira–Sunose, Flynn–Wall–Ozawa, and Friedman) were used to develop the kinetic model of pyrolysis of the MFPW samples. The results showed that the main decomposition of the MFPW samples happened in the range 360-500˚C with mass loss of 67–96%, while the kinetic models indicated that the mean activation energies for the mixture sample were estimated at 288.8 kJ/mol (Kissinger), 287.8 KJ/mol (KAS), 314.5 KJ/mol (FWO), and 307.9 KJ/mol (Friedman). Finally, the FTIR spectra and GC–MS results showed that Propene and Furan (7.6%), 2,4-Dimethyl-1-heptene and Isopropylcyclobutane (43.16%), etc. compounds were strongly present in the released volatile products. [ABSTRACT FROM AUTHOR]

• Heat induces stress in growth and physiology of B. napus only under drought conditions. • Drought + heat accelerates soil drying resulting in more damage than do drought alone. • Nutrient deficiency, by itself, evoke strong stress under control conditions. • Under stress conditions, plant C/N ratio negatively correlates with plant N dynamics. • Drought + heat + nutrient deficit results in badly disturbed PSII and C/N balance. Extreme climatic conditions with extended drought periods and heatwaves are predicted to increase in frequency and severity in many regions of the world. Aside from this, other abiotic stress factors such as nutrient deficiency could pose a serious problem to plants when combined with other stressors resulting in more complex underpinning mechanisms. In the present study, we evaluated the response of Brassica napus to single and combined impacts of drought and heatwave (HW) under adequate or deprived (N-A and N-D) soil nutrient conditions. In addition, to get better insights in the plant response to combined stress, a post-stress period, pointing out a degree of the recovery after the cessation of stress, was also included. The results showed a different manner of single drought and heatwave action. The adverse effect of drought on leaf gas exchange was lagged on the growth and became more apparent only after recovery period with no obvious difference between different nutrient levels. Contrary, the growth response of nutrient-deprived plants to single HW was weak and in most cases, insignificant. Heatwave applied simultaneously with drought highly exacerbated the adverse effect of drought both under N-A and N-D conditions. Combined drought and heatwave stress resulted in the sharper decline of A sat and it was attributed to both stomatal and non-stomatal limitations. Interestingly, plants underwent combined drought and HW treatment under N-D conditions showed better aboveground growth recovery, compared to those grown under N-A conditions, while displayed far more diminished photochemistry of photosystem II and badly disturbed the C/N balance. This discrepancy came from the fact that soil nutrient deficiency, by itself, evoked strong stress under control climate conditions resulting in a dramatically slower aboveground growth of nutrient-deprived plant. In turn, although combined drought and HW stress had similar effect on the aboveground growth either under N-A or N-D conditions, the recovery of later one was better. These results highlight the necessity to look at plants' performance under unfavorable environmental conditions beyond the actual event, since it can be depended not only on the duration of exposure but also on the legacy effect after treatment. [ABSTRACT FROM AUTHOR]

The depletion and usage of fossil fuels causes environmental issues and alternative fuels and technologies are urgently required. Therefore, thermal arc water vapor plasma for a fast and robust waste/biomass treatment is an alternative to the syngas method. Waste cooking oil (WCO) can be used as an alternative potential feedstock for syngas production. The goal of this experimental study was to conduct experiments gasifying waste cooking oil to syngas. The WCO was characterized in order to examine its properties and composition in the conversion process. The WCO gasification system was quantified in terms of the produced gas concentration, the H2/CO ratio, the lower heating value (LHV), the carbon conversion efficiency (CCE), the energy conversion efficiency (ECE), the specific energy requirements (SER), and the tar content in the syngas. The best gasification process efficiency was obtained at the gasifying agent-to-feedstock (S/WCO) ratio of 2.33. At this ratio, the highest concentration of hydrogen and carbon monoxide, the H2/CO ratio, the LHV, the CCE, the ECE, the SER, and the tar content were 47.9%, 22.42%, 2.14, 12.7 MJ/Nm3, 41.3% 85.42%, 196.2 kJ/mol (or 1.8 kWh/kg), and 0.18 g/Nm3, respectively. As a general conclusion, it can be stated that the thermal arc-plasma method used in this study can be effectively used for waste cooking oil gasification to high quality syngas with a rather low content of tars. [ABSTRACT FROM AUTHOR]