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Greenhouse gases from the propulsion systems of road transportations constitute a significant obstacle to achieve the Paris Agreement objectives. Nowadays, the substitution of conventional internal combustion engines with electric motors, along with electrochemical storage systems are the leading efforts to reduce the use of fossil fuels in road transportations. However, their limited driving range and the long charging times are the main technical factors that hinder the development of electromobility. Thus, energy harvesters and regeneration systems are increasingly incorporated in road vehicles, in order to increase their driving range. In this context, Vehicle Integrated and Applied Photovoltaics (VIAPVs) constitute an attractive prospect. The electricity yield for VIAPVs depends strongly on the route, the shadings due to the urban environment, the applied Maximum Power Point (MPPT) algorithm and the traffic conditions. In this paper, four commonly used commercial MPPT algorithms are experimentally evaluated, regarding their ability to extract the maximum available power simulating realistic city routes. The results show notable discrepancies in the performance of the studied algorithms, between terrestrial and VIAPV applications, highlighting the impact of poor MPPT performance in terms of power generation in moving vehicles. • MPPTs experimental evaluation, emulating real life scenarios for on-vehicle PVs. • Four commercial MPPT algorithms are considered in this study. • In an urban environment, MPPT dynamic performance is crucial for on-vehicle PVs. • Energy yield of on-vehicle PVs depends on urban environment, MPPTs and traffic. [ABSTRACT FROM AUTHOR]

System simulation is necessary to investigate the feasibility of Solar PV system at a given location. This study is done to evaluate the feasibility of grid connected rooftop solar photovoltaic system for a residential Hostel building at MANIT, Bhopal, India (Latitude: 23° 16′ N, Longitude: 77° 36′ E). The study focuses on the use of Solargis PV Planner software as a tool to analyze the performance a 110 kWp solar photovoltaic rooftop plant and also compares the performances of different PV technologies based on simulated energy yield and performance ratio. Solargis proves to easy, fast, accurate and reliable software tool for the simulation of solar PV system.

Fossil fuels (Natural gas, heavy and light oil) are considered the main sources for electricity generation in Libya. Libya’s electricity demand is growing at a rapid rate and the country will require significant additional capacity in the coming years due to the development of all sectors of life and the improvement of individuals’ life quality, without taking into account the rationalization of electricity consumption. Th main reason for this is that Libya has a very high energy subsidy, especially the tariff set by the Libyan state for the price per kilowatt-hour for electricity sector. Th heavily subsidized electricity price for household currently stands at (20 dirham’s/kilowatt-hour) compared to (100 dirham’s/kilowatt-hour), as the domestic price of fuel cost, and in return (450 dirham’s/kilowatt-hour) as the electricity cost of fuel in international prices. In order to reduce the deficit and the ongoing balancing in energy demand with the amount of generation of available capacity it is necessary to study all electrical systems for the future, the most important of which are wind energy and solar energy projects to meet a significant part of this demand, and to reduce, as much as possible, the carbon dioxide emissions. This paper deals with the wind data processing at the site coupled with the city and its relationship to electricity generation. It presents long term wind data analysis, in terms of averages of ten minute values of wind speed were used to get yearly mean values for a period of 1 year, between 04/11/2002 and 30/12/2003. Most frequent wind directions are NW, N, NNW and WNW. Thy represent about 50%, followed by E, ESE and SE. In general, East and SE winds are relatively frequent but weak at the same time. The most powerful directions are NW, WNW, W and NNW which by far - represent about 46% of the expected power, followed by N. It should be noted that the high frequency of north direction winds that come from the desert can cause a high frequency of dust episodes. This fact should be taken into consideration in order to take appropriate measures to prevent wind turbine deterioration. The annual energy yield and wind direction were evaluated for AL-Magrun town, considering wind turbines ranging between 1.65 MW and 2 MW (power curve considering air density 1.225 kg/m3). Th wind turbine (Gamesa 90/2000) recorded the highest values, equaling (6.05GWh,3023Eqh) and (M. Torres TWT 1.65-82 ) equalling (4.39 GWh, 2660 Eqh) compared to the rest of the turbines studied. These values encouraged us to take advantage of wind power to achieve economic benefits.

In Poland, existing barrages are characterized by relatively high flow and low head, which is challenging for the effective utilization of theoretical watercourse power. The paper presents the impact of the minimum head of the hydro sets on the annual electricity production of small hydropower plants at low-head locations for two types of water turbines: Archimedes and Kaplan turbines. A developed mathematical model was used to simulate energy yield from Archimedes and Kaplan turbines for a given value of the minimum technical head, depending on the number of installed hydro sets. For economic analysis purposes, the levelized cost of electricity (LCOE) and net present value (NPV) indicators were calculated. The conducted research allowed for comparing Archimedes and Kaplan’s turbine operating conditions and how the minimum head parameter influences their electricity production and utilization time. As concluded in the results, the influence of minimum head in energy production is more distinct for the Archimedes screw technology than for the Kaplan turbine. The research shows that the decrease in energy production associated with the hydro unit’s minimum head parameter is from 0% to 30% for Kaplan, and it is 6% to 52% for Archimedes turbines.

The present pilot study examined the potential of tobacco (Nicotiana tabacum L.) as an energy source. The fresh matter of whole tobacco plants, the yield of dry matter of stems and leaves, as well as the higher heating value and methane production potential from tobacco biomass were determined. The yield of tobacco leaves was on average 4.69 Mg ha−1 (dry matter) and 76.90 GJ ha−1 yr−1 (biomass energy yield). Tobacco stems yielded on average 8.55 Mg ha−1 and 150.69 GJ ha−1 yr−1, while yields of whole tobacco crops were (on average) 13.24 Mg ha−1 and 227.59 GJ ha−1 yr−1. Methane potential of tobacco plants was (on average) 248 Nm3 Mg−1 VS (volatile solids). The tobacco plants tested in the study could be used as energy crops as their dry matter and energy yields are similar to those of the most popular energy crops being currently used in biomass production in Poland and the European Union. Nevertheless, further studies to choose the Nicotiana species and varieties most suitable for energy production and to assess the cost-effectiveness of tobacco biomass production are needed.

To achieve clean and high-quality spinach production, the effects of daily light integral (DLI) and light spectrum on growth, nutritional quality, and energy yield of hydroponic spinach (Spinacia oleracea L.) were investigated in a closed plant factory under light-emitting diode (LED) lighting. The hydroponic spinach plants were grown under 16 combinations of four levels of DLI (11.5, 14.4, 17.3, and 20.2 mol m−2 day−1) with four light spectra: LED lamps with ratio of red light to blue light (R:B ratio) of 0.9, 1.2, and 2.2 and fluorescent lamps with R:B ratio of 1.8 as control. The results show that total fresh and dry weights, energy yield, and light energy use efficiency (LUE) of harvested spinach were higher under D17.3-L1.2 treatment compared to other treatments. The higher net photosynthetic rates were shown at DLI of 17.3 mol m−2 day−1 regardless of light quality. Higher vitamin C contents of spinach in all LED treatments were obtained compared with the control. L1.2 treatments with higher fraction of blue light led to more vitamin C content, lower nitrate content, and higher LUE independent of DLI. L2.2 treatment with more fraction of red light was beneficial to reduce oxalate accumulation. Power consumption based on increased total fresh weight under LED lamps with R:B ratio of 1.2 in different DLIs was over 38% lower than that under the fluorescent lamps and 1.73 kWh per 100 g FW at DLI of 17.3 mol m−2 day−1. In conclusion, lighting environment in DLI of 17.3 mol m−2 day−1 using LED lamps with R:B ratio of 1.2 is suggested for the design of a LED plant factory for hydroponic spinach production.

The aim of this research is to perform an in-depth performance comparison of ground-mounted and rooftop photovoltaic (PV) systems. The PV modules are tilted to receive maximum solar irradiance. The efficiency of the PV system decreases due to the mutual shading impact of parallel tilted PV modules. The mutual shading decreases with the increasing interrow distance of parallel PV modules, but a distance that is too large causes an increase in land cost in the case of ground-mounted configuration and a decrease in roof surface shading in the case of rooftop configuration, because larger sections of roof are exposed to sun radiation. Therefore, an optimized interrow distance for the two PV configurations is determined with the aim being to minimize the levelized cost of energy (LCoE) and maximize the energy yield. The model of the building is simulated in EnergyPlus software to determine the cooling load requirement and roof surface temperatures under different shading scenarios. The layout of the rooftop PV system is designed in Helioscope software. A detailed comparison of the two systems is carried out based on energy output, performance ratio, capacity utilization factor (CUF), energy yield, and LCoE. Compared to ground-mounted configuration, the rooftop PV configuration results in a 2.9% increase in CUF, and up to a 23.7% decrease in LCoE. The results of this research show that installing a PV system on a roof has many distinct advantages over ground-mounted PV systems such as the shading of the roof, which leads to the curtailment of the cooling energy requirements of the buildings in hot regions and land cost savings, especially for urban environments.

The main objective of this paper is to experimentally assess the real-life outdoor performance of a photovoltaic-thermal (PVT) module against a conventional photovoltaic (PV) system in a hot humid tropical climate in Ghana. An experimental setup comprising a water-based mono-crystalline silicon PVT and an ordinary mono-crystalline silicon PV was installed on a rooftop at the Kwame Nkrumah University of Science and Technology in Kumasi and results evaluated for the entire year of 2019. It was observed that the annual total output energy of PV module was 194.79 kWh/m2 whereas that of the PVT for electrical and thermal outputs were 149.92 kWh/m2 and 1087.79 kWh/m2, respectively. The yearly average daily electrical energy yield for the PV and PVT were 3.21 kWh/kWp/day and 2.72 kWh/kWp/day, respectively. The annual performance ratios for the PV and PVT (based on electrical energy output only) were 79.2% and 51.6%, respectively, whilst their capacity factors were, respectively, 13.4% and 11.3%. Whereas the highest monthly mean efficiency recorded for the PV was 12.7%, the highest combined measured monthly mean electrical/thermal efficiency of the PVT was 56.1%. It is also concluded that the PVT is a worthy prospective alternative energy source in off-grid situations.

In the present study, the possibility of improving the higher heating value (HHV) of lignocellulosic biomass, especially barley straw, was examined. The research deals with the treatment of barley straw by acid-catalyzed wet torrefaction (ACWT), also called acid hydrolysis, in a batch reactor (autoclave) Parr 4553 3.75 L. In this case, two different simulation approaches were applied: (i) combined severity factor (CSF) and (ii) response surface methodology (RSM) based on Box–Behnken design of experiments (DoE). Sulfuric acid (SA) concentration, temperature and time were the ACWT parameters examined herein. An oxygen bomb calorimeter was used for the HHV measurement. The findings indicated that the composition changes of the straw due to ACWT had a significant effect on the HHV of the pretreated material. In this study, treatment conditions were 10–35 mM SA, 160–200 °C and an isothermal reaction time 0–40 min (preheating period not included in these values). In conclusion, there was a significant increase in the HHV up to 24.3 MJ/kg for the ACWT barley straw, compared to 17.5 MJ/kg for the untreated straw, at optimal conditions of 200 °C for 25 min (isothermal period) and 35 mM SA. This resulted in a 1.39 enhancement factor (EF) and 68% energy yield (EY).

Many recent studies focused on the research of thermal treated biomass in order to replace fossil fuels. These studies improved the knowledge about pretreated lignocellulosics contribution to achieve the goal of renewable energy sources, reducing CO2 emissions and limiting climate change. They participate in renewable energy production so that sustainable consumption and production patterns can by ensured by meeting Goals 7 and 12 of the 2030 Agenda for Sustainable Development. To this end, the subject of the present study relates to the enhancement of the thermal energy content of barley straw through torrefaction. At the same time, the impact of the torrefaction process parameters, i.e., time and temperature, was investigated and kinetic models were applied in order to fit the experimental data using the severity factor, R0, which combines the effect of the temperature and the time of the torrefaction process into a single reaction ordinate. According to the results presented herein, the maximum heating value was achieved at the most severe torrefaction conditions. Consequently, torrefied barley straw could be an alternative renewable energy source as a coal substitute or an activated carbon low cost substitute (with/without activation treatment) within the biorefinery and the circular economy concept.

Abstract The cost of creating an inert atmosphere is one of the main expenses associated with torrefaction. For reducing the operating cost, torrefaction of poplar sawdust is conducted in a semi-closed system without an inert atmosphere. The effect of self-generated volatiles from torrefaction in a semi-closed system on mass and energy yields, HHV, elemental analysis, thermal properties, chemical structures, grindability and hydrophobicity of torrefied biomass was investigated, and then compared with torrefaction in nitrogen medium. Results show that properties of torrified biomass in a semi-closed system are almost the same as those in nitrogen medium. However, the thermal performance of torrefied biomass obtained from a semi-closed system is superior to that from nitrogen medium because of the relatively easy accessed thermal reactions, as indicated by low peak temperature in DTG. The decreased peak temperature is related to oxidized cellulose and lignin with increased contents of carboxyl, carbonyl, and ether groups in torrefied biomass obtained in the presence of generated volatiles. Highlights • Torrefaction of poplar sawdust in generated volatiles and nitrogen medium. • Similar weight loss and heating value were obtained at less severe conditions. • Differences in peak temperatures in DTG were found. • Higher intensity of C O and C O bonds in biochar results in less thermal stability. • High volatiles concentration leads to more oxygen-containing and aromatic groups. [ABSTRACT FROM AUTHOR]

Abstract Oxidative torrefaction of briquetted birch shavings inside the quiescent layer of bentonite clay was investigated in a muffle furnace. In the considered process the briquettes are buried under the layer of bentonite clay and the reactor is heated at atmospheric conditions without the use of inert gas. The main role of the bentonite clay is to limit the oxygen access to the torrified biomass from the environment. The paper considers the effects of briquette thickness, bentonite layer height, temperature and torrefaction duration on the mass yield and energy yield of the biomass. It is shown that to increase the enhancement factor of HHV of the biomass it is necessary to reduce both the height of bentonite clay and the briquette thickness. As well the torrefaction temperature and duration should be increased. It is also established that the height of bentonite layer affects negligibly on the energy yield. • Torrefaction of wooden briquettes in the layer of bentonite clay. • Bentonite limits the oxygen access to the biomass. • Mass yield increases with the briquette thickness. • Height of bentonite layer affects insignificantly the energy yield. • Increase in torrefaction temperature and duration leads to the decrease in mass yield. [ABSTRACT FROM AUTHOR]

Abstract Torrefaction is a mild pyrolysis, which is used for biomass pretreatment aimed to increase the heating value and hydrophobicity. Nowadays there are a lot of various torrefaction techniques. The heating of the wood pellets or briquettes inside the layer of mineral particles under atmospheric conditions can represent one of the prospective torrefaction techniques. Significant diffusion resistance of the mineral layer can favor substantial reduction in the oxygen flux to the biomass from the environment. Due to this one can carry out torrefaction without the use of inert gas. The paper analyzes experimentally the torrefaction of pine pellets inside the layer of bentonite clay or microcalcite. It is established experimentally that the height of mineral layer does not affect significantly on the mass yield at 230°C. However, under the conditions of severe torrefaction (290°C) the increase in mass yield with height of mineral layer is observed. The calorific properties of torrefied biomass are estimated on the basis of elemental analysis. It is shown that the value of energy yield increases together with the mass yield. Graphical abstract Unlabelled Image Highlights • Torrefaction of wood pellets inside the layer of bentonite or microcalcit • Torrefaction is carried out without the use of inert gas. • Mineral layer limits the oxygen access to the biomass. • At high temperatures the mass yield depends on the height of mineral layer. • Energy yield of biomass increases together with a mass yield. [ABSTRACT FROM AUTHOR]

Abstract Solar Photovoltaic systems are widely accepted as alternate energy sources across the world. Grid Tied PV (GTPV) and Grid Interactive (GIPV) PV systems are the two configurations in which PV generation is integrated with Grid. Later is more complex due to inclusion of battery as storage and connected load, along with Grid import/export. In this paper, performance of a 40 kWp GIPV system, installed in India, is presented. The system under study comprises of PV, Grid, and Battery bank and connected load. Performance parameters like reference yield, array yield, final yield, performance ratio, and capacity factor are derived using standards IEC 61724. Also presented is Annual energy yield of the plant and Annual efficiencies of PV array, inverter and system. The effect of temperature on PV array and inverter performance is also evaluated. All these parameters are evaluated from real time annual data. [ABSTRACT FROM AUTHOR]

Bifacial silicon Photovoltaic (PV) technology has the advantage of generating more energy output as compared with the conventional mono-facial technology. In this paper, a comparison is made between the performances of two bifacial silicon heterojunction modules mounted at two configurations under Qatar's climatic conditions: a tilt angle of 22° facing south and a tilt angle of 90° (vertical) facing east-west. The bifacial module mounted under standard tilt showed a 14% higher energy yield over the vertically tilted bifacial module. This is mainly due to higher irradiance received by the 22° tilted module relative to the vertically tilted module. On the other hand, a thermal model has been developed using COMSOL Multiphysics to calculate the theoretical power output, energy yield and module temperature. A gain in the short circuit current is found to increase linearly with the ratio of the diffuse irradiance to plane of array irradiance. [ABSTRACT FROM AUTHOR]

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In this study, the effect of pre-treatments including alkaline, acid and hydrogen peroxide on continuous hydrogen and methane production was investigated. Two different substrates as potatoes and bean wastes were used. Pre-treatment showed positive effect on bio-hydrogen and bio-methane production; higher bio-hydrogen and bio-methane production results using pre-treated samples than the control bioreactors (without pre-treatment), were recorded. In case of potatoes wastes, the hydrogen yield ranged between 126.4 and 252.7 mL-H 2 /g-TVS using pre-treated samples compared to 58.7 mL-H 2 /g-TVS observed in the reference test. Pre-treated bean wastes showed hydrogen yield of 93.0–152.1 mL-H 2 /g-TVS higher than 53.3 mL-H 2 /g-TVS measured in the control test. In the second stage, average methane yield results of 322.9–507.1 and 284.3–462.6 mL-CH 4 /g-TVS higher than 198.6 and 124.3 mL-CH 4 /g-TVS measured for potatoes and bean wastes control bioreactors, respectively. The best results were observed using H 2 O 2 pre-treatment. The energy production efficiency was improved by combining H 2 and CH 4 bioreactors. [ABSTRACT FROM AUTHOR]

The work is devoted to substantiating the use of metallic hafnium as the emitter of the Compton (prompt-response) in-core detector of thermal and resonant neutrons. The main trends in the development of nuclear power engineering, which raise the interest in the use of hafnium, are considered. The known data on the behavior of both Compton and β- emission self-powered neutron detectors (SPND) are generalized. The Compton SPND signal formation mechanism for the case of the irradiation by reactor-type fluxes of neutrons and gamma quanta is considered. The paper presents the calculation result of the hafnium burning-out degree for the conditions of WWER and RBMK reactors. The influence of the gamma radiation “sources”, which provide the largest contribution to the electrons production in the detector is considered. [ABSTRACT FROM AUTHOR]

Torrefaction of biomass is a thermochemical process to enhance its fuel characteristics such as energy density and hydrophobicity. In this study, oil palm frond, a highly abundant agricultural waste in Malaysia is the feedstock of interest to investigate the influence of torrefaction temperature on its thermochemical properties. A single holding time of 30 min is used, with temperatures in the range of 200°C to 300°C (25°C increments). The mass and energy yields, as well as energy densification ratio are investigated, along with proximate analysis. Both mass and energy yield decreased with increasing torrefaction temperatures. The higher heating value (HHV) of torrefied oil palm fronds increased with increasing torrefaction temperature. Mild torrefaction temperatures (200°C - 225°C) showed insignificant improvements to HHV and slight reductions in mass and energy yields. Moderate and high torrefaction temperatures increased HHV significantly, while mass and energy yields continued to decrease. The optimum torrefaction temperature is determined to be at 250°C, giving the torrefied oil palm frond a respectable HHV of 26.62 MJ/kg, while maintaining an energy yield of 92.70%. This is within the range of HHV of coal, thus positioning torrefied oil palm frond as a suitable co-firing fuel for coal power plants. [ABSTRACT FROM AUTHOR]

This study presents a new formulation for real‐time active network management (ANM) control of distribution networks to maximise energy yield from distributed generation (DG). Coordinated scheduling of renewable DG and distribution network control assets can limit DG curtailment and significantly increase energy yield and economic performance of DG in weak or congested networks. Optimal power flow (OPF) has been employed in the literature for this purpose. However, single time frame snapshot formulations are limited by their narrow interpretation of temporal constraints. Here a formulation is presented for a new receding‐horizon OPF technique to better control real‐time ANM in distribution networks with high levels of temporally and spatially variable renewable DG. It is shown to improve the coordination between time sequences of system dispatch and improve voltage performance. [ABSTRACT FROM AUTHOR]

Human activities have contaminated water sources with pharmaceutical compounds by the improper disposal of unwanted medicine or through sewage waste. The search for the most effective water treatment processes has been ongoing for decades. In the current paper, by exposing water to non-thermal plasma in a floating electrode streamer corona discharge (FESCD) system, both the antidepressant compound fluoxetine and the antihypertensive compound propranolol are eliminated. After 3 h of plasma treatment, more than 99% of each contaminant was degraded. The energy yield, which is the amount of contaminants degraded using 1 kWh of energy, was in the range of 0.12–0.13 g/kWh. The degree of mineralization calculated from total organic carbon (TOC) measurements was 60% and 17% for fluoxetine and propranolol, respectively. Reaction with hydroxyl radicals was the only degradation pathway for fluoxetine and its byproducts. For propranolol, hydroxyl radicals primarily caused the degradation butoxidation of secondary alcohols to ketones suggested the possible role of ozone molecules. [ABSTRACT FROM AUTHOR]

Co-location of wind and tidal stream turbines provides opportunity for improved economic viability of electricity generation from these resources relative to projects exploiting each resource separately. Here co-deployment is assessed in terms of energy generation and loading of support structures. Energy yield is modelled using an eddy viscosity wake model for wind turbines and superposition of self-similar wakes for tidal turbines. A case-study of the Inner Sound of the Pentland Firth is considered. For 3.5 years of coincident resource data, 12 MW wind capacity co-located with a 20 MW tidal array results in a 70% increase in energy yield, compared to operating the tidal turbines alone. Environmental loads are modelled for a braced monopile structure supporting both a wind and tidal turbine, as well as for each system in isolation. Peak loading of the combined system is found to be driven by wind loads with greatest overturning moment occurring with the wind turbine operating at close to rated-speed and the tidal turbine close to its shutdown speed. Mean loads vary across the tidal array by 6% indicating no significant shielding effects are gained by co-locating in more sheltered regions of the array. [ABSTRACT FROM AUTHOR]

The rapid growth of electricity demand due to the increase in population has put the burden on the power stations of India to enhance their generation. With the serious drop in prices of solar photovoltaic (SPV) generated electricity and rising tariffs on conventional electricity have drawn attention to generate electricity through the solar photovoltaic plant. Therefore, it is important to assess accurately and precisely the annual and monthly yield of SPV plant to help in designing and installation of new plants. Performance analysis of a 5 kWp roof-top photovoltaic plant has carried out, and the effect of temperature analyzed. The annual average daily reference yield, array yield, and final yield found 5.23 kWh/kWp/day, 4.51 kWh/kWp/day and 3.99 kWh/kWp/day respectively. The annual average daily array efficiency, inverter efficiency and system efficiency found to be 11.34%, 88.38%, and 10.02% respectively. The annual average daily performance ratio and capacity utilization factor measured 76.97% and 16.39%. The annual energy yield of the plant recorded 7175.4 kWh. Results show that energy loss is maximum during May when the temperature is highest. The performance of the plant compared with PV plants installed all over in India and found comparable. [ABSTRACT FROM AUTHOR]

This paper presents a methodology to evaluate the influence of downtime on the long-term energy yield of a floating wind farm. It is based on the definition and integration of three models: a discrete event model, which simulates failures and reparation times, a floating wind turbine model, which simulates platform motions and operational stops, and a wind farm model, which models wake effects between turbines. The methodology is applied to a wind farm composed by ten floating turbines and located off the coast of Cantabria, Spain. Results indicate that downtime affects significantly the mean energy yield of the farm, which decreases linearly with the mean failure rate, mean reparation time and probability of exceedance of the operational thresholds for the considered case studies. [ABSTRACT FROM AUTHOR]

The study was conducted in the period 2014-2016 in the experimental field of the Institute of Maize - Knezha. The subject of the study are the hybrids: Kn- 517 group 500-600 per FAO and density 5500-6000 p/da and Kn-613 group over 600 per FAO and density 5200-5700 p/da. The maize was grown in a control variant without fertilization (T0) and two fertilizing levels: N8,5P5,4K6,4 (T1) and N17P10,8K12,8 (T2). The agrotechnics adopted for the region was applied. For hybrid Kn-517 and density 5500 p/da and at both fertilization levels T1 and T2 yields increased by 26%. For a density of 6000 p/da this increase is 30% for fertilization N8,5P5,4K6,4 and 27% for N17P10,8K12,8. For hybrid Kn-613 and density 5200 p/da the difference in energy yield relative to the control (T0) is 33% for the single dose of the (T1) and 31% for the double – T2). For a density of 5700 p/da the effect of fertilization is 34% and 31%, respective for the variants T1 and T2. For hybrid Kn-517 and 5500 p/da bioenergy coefficient was changed from 3.2 for T1 to 1.6 for variant T2. For a density of 6000 p/da those values are 3.9 and 1.7 for fertilizing with N8,5P5,4K6,4 and 27% for N17P10,8K12,8. By year the bioenergetics coefficient was with the lowest value of 0.7 for T2 variant and 5500 p/da for the first year and the highest of 5.6 for the T1 and 6000 p/da for the third year. For hybrid Kn-613 and 5200 p/da research indicator changed from a range of 3.5 for the single to 1.6 for a doubled fertilizer and for a density of 5700 p/da values were 3.7 and 1.6. For densities this value has the lowest value of 0.6 at the double fertilizer norm T2 for 2014. The highest result was calculated in the second year and variant T1 respective by 4.5 for 5200 p/da and 5.0 for 5700 p/da. [ABSTRACT FROM AUTHOR]

Corncob (CC) was converted to renewable fuel resource by hydrothermal carbonization (HTC). HTC was performed by varying process temperature (160–200 °C), residence time (1–3 h), and biomass to water ratio (BTW) (1:5 to 1:15). The properties of hydrochar were significantly enhanced where the fixed carbon and carbon content of hydrochar increased at about 24.9 and 83.7% from original contents in CC, respectively. The calorific values and yield of hydrochar were between 19.3–23.5 MJ/kg and 50.1–58.6%. The optimal condition for the production of hydrochar as solid fuel was determined at 200 °C, 3 h residence time, and BTW of 1:5 with maximum energy yield of 68.74%. In addition, hydrothermal liquid was characterized where volatile fatty acid, furfural, furfuryl alcohol, and hydroxymethylfurfural were the most abundant compositions with their highest yields of 17.3, 11.5, 7.9, and 5.1%, respectively. Process temperature was the most influencing variable on product properties and characteristics. The results suggested that corncob has high potential as a source for solid fuel and valuable platform chemicals. [ABSTRACT FROM AUTHOR]

Ozonation and advanced oxidation processes based on photocatalysis (P.C.) and non-thermal plasma generated in a dielectric barrier discharge (DBD) in different gas atmospheres were compared for the degradation and mineralization of 2,4-dichlorophenoxy acetic acid (2,4-D) and 2,4-dichlorophenol (2,4-DCP) in aqueous solutions, using a planar falling film reactor with comparable design. The energetic yields (G 50 ) as measure of the efficiencies of the different methods are for 2,4-D in the order DBD/Ar-Fenton > ozonation > DBD/Ar > P.C.ozonation > DBD/Ar:O 2 ≫ DBD/Air > P.C.oxidation. For 2,4-DCP the order is ozonation ≫ DBD/Ar-Fenton > P.C.ozonation > DBD/Ar > DBD/Ar:O 2 ≫ P.C.oxidation > DBD/Air. The degradation by using ozone is very effective, but it should be noted that the mineralization measured by the total organic carbon (TOC) removal is low. The reason is the formation of stable towards ozone intermediates, especially low chain carboxylic acids. The fate of these intermediates during the degradation with the different methods has been followed and discussed. [ABSTRACT FROM AUTHOR]

Textile waste torrefaction was investigated as a novel means to assist in waste valorization and energy management practices. This study analyzed the thermal behavior and fuel properties of textile waste subjected to torrefaction at 225, 250, 275 and 300 °C for 1 and 3 h at a constant heating rate of 15 °C/min. The energy and carbon contents of torrefied textiles were greatly enhanced whilst unusually high energy yields above 100% were recorded due to the energy densification process. Reduced atomic H/C and O/C ratios revealed that the fuel characteristics and reactivity of torrefied textiles converged towards those of coal. FTIR analysis indicated that torrefaction altered the chemical structure of textile waste with respect to its hemicellulose and cellulose contents. A strong linear correlation was observed between mass loss and the energy properties of torrefied textile biochar. This demonstrated the effectiveness of mass loss as a synthetic indicator of the degree of torrefaction. The analytical expressions derived experimentally represent essential tools that can be used in the optimization of the torrefaction process. Torrefied textiles can eventually assist in the displacement of important fractions of coal in thermal conversion systems in the long run. [ABSTRACT FROM AUTHOR]

The efficiencies of ozonation and different advanced oxidation processes (AOPs) including photocatalytic ozonation, Fenton, photo-Fenton, photocatalytic oxidation, UVA/Ti02/H202, and non-thermal plasma generated by a dielectric barrier discharge (DBD) were compared in terms of the energy yield (G50) for decolorization of MB and total organic carbon (TOC) removal using a planar falling film reactor. Fenton oxidation and ozonation were found to be the most efficient methods for the decolorization of MB, although these techniques attained rather low mineralization. A combination treatment of the ozonation with the photocatalysis demonstrates a synergistic effect on the mineralization efficiency. The photocatalytic oxidation and UVA/Ti02/H202 provide only a moderate MB decolorization. The degradation efficiency of the DBD plasma is significantly dependent on the composition of gas atmosphere. The addition of Fe2+ to the solution in the DBD plasma under argon atmosphere improves the degradation efficiency due to the occurrence of Fenton reaction. The energy yield for 50% conversion of MB is calculated between 0.13 and 20.5 g/kWh, and the maximum and minimum values were obtained by the ozonation and photocatalytic oxidation, respectively. Ozonation with the highest energy yield provided a moderate mineralization by only 19%, while the DBD plasma obtained the highest TOC removal by 88%. [ABSTRACT FROM AUTHOR]

The efficiencies of ozonation and different advanced oxidation processes (AOPs) including photocatalytic ozonation, Fenton, photo-Fenton, photocatalytic oxidation, UVA/TiCVPčb, and non-thermal plasma generated by a dielectric barrier discharge (DBD) were compared in terms of the energy yield (G50) for decolorization of MB and total organic carbon (TOC) removal using a planar falling film reactor. Fenton oxidation and ozonation were found to be the most efficient methods for the decolorization of MB, although these techniques attained rather low mineralization. A combination treatment of the ozonation with the photocatalysis demonstrates a synergistic effect on the mineralization efficiency. The photocatalytic oxidation and UVA/TIO2/H2O2 provide only a moderate MB decolorization. The degradation efficiency of the DBD plasma is significantly dependent on the composition of gas atmosphere. The addition of Fe2+ to the solution in the DBD plasma under argon atmosphere improves the degradation efficiency due to the occurrence of Fenton reaction. The energy yield for 50% conversion of MB is calculated between 0.13 and 20.5 g/kWh, and the maximum and minimum values were obtained by the ozonation and photocatalytic oxidation, respectively. Ozonation with the highest energy yield provided a moderate mineralization by only 19%, while the DBD plasma obtained the highest TOC removal by 88%. [ABSTRACT FROM AUTHOR]

The study was done in the period 2014-2016 in the experimental field of the Institute of Maize - Knezha. The subject of the study are hybrids: Kn-307 group 200-400 per FAO and a density of 6500- 7000 p/da and Kn-435 group 400-500 per FAO and density of 6000-6500 p/da. The maize was grown under control without fertilization (T0) and two fertilization levels: N8,5Р5,4К6,4 (T1) and N17P10,8K12,8(T2). The agrotechnics adapted for the region was applied. For Kn-307 hybrid and density of 6500 p/da, mineral fertilization increased the yield of energy by 27-26% for variants T1 and T2 and by 33% respectively about two doses of fertilizer T1 and T2 and density of 7000 p/da. At both fertilization levels T1 and T2 and the two densities 6000-6500 p/da for the hybrid Kn-435, the yield of energy was 30-33% more than the control (T0). Average for period, the fertilization with N8,5Р5,4К6,4 the bioenergetic coefficient for the hybrid Kn-307 was changed from 3.6 to 4.2. For doubled fertilizer N17P10,8K12,8this indicator ranged from 1.8 to 2.1. For years, the bioenergy coefficient was with the lowest value of 0.8 for T2 variant and 6500 p/da for the first year and the highest of 5.6 for the T1 and 7000 p/da for the third year. For Kn-435 and 6000 p/da the survey indicator changed from 4.2 to 2.3 for the single T1 and the double dose of fertilizerT2, and for the density of 6500 p/da these values were 4.3 and 2.2. [ABSTRACT FROM AUTHOR]

Trichloroethylene is carcinogenic and poorly degraded by microorganisms in the environment. Advanced Oxidation Technology is considered to be an effective treatment technology for TCE degradation. In this study, a double dielectric barrier discharge (DDBD) reactor was established to decompose TCE. The influence of different condition parameters on DDBD treatment of TCE was investigated to determine the appropriate working conditions. The chemical composition and biotoxicity of TCE degradation products were also investigated. Results showed that when SIE was 300 J L−1, the removal efficiency could reach more than 90%. The energy yield could reach 72.99 g kWh−1 at low SIE and gradually decreased with the increase of SIE. The k of the Non-thermal plasma (NTP) treatment of TCE was about 0.01 L J−1. DDBD degradation products were mainly polychlorinated organic compounds and produced more than 373 mg m−3 ozone. Moreover, a plausible TCE degradation mechanism in the DDBD reactors was proposed. Lastly, the ecological safety and biotoxicity were evaluated, indicating that the generation of chlorinated organic products was the main cause of elevated acute biotoxicity. [Display omitted] • Effects of some operational conditions on TCE removal by DDBD were evaluated. • Energy yield and kinetics of TCE degradation by DDBD were calculated. • The possible decomposition pathways of DDBD in this system were proposed. • Residual toxicity after DDBD decomposition was significantly increased. [ABSTRACT FROM AUTHOR]