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In this experiment, oxygen bomb calorimetry was used to optimize the determination conditions of gross energy of feed fat and oil. Soybean oil and blended oil were selected as experimental materials to study the effect of matrix addition on the results of gross energy determination and optimize the detection method. Eleven types of feed fats and oils were selected as experimental materials to verify the influence of different sample masses (0.4, 0.6, 0.8, 1.0, 1.2 g) on the determination results, while five types of fats and oils were selected to compare the influence of different instruments on the determination results. The results showed that matrix addition resulted in a large coefficient of variation and poor repeatability when determining the gross energy of soybean oil (P<0.05), while no matrix group showed good repeatability (P>0.05). The intra-day and inter-day measurement with no matrix showed insignificant differences in determination results, which indicated good stability of the results (P>0.05). The different sample masses had no significant effect on the determination results of nine types of feed fats and oils, such as soybean oil, blended oil, coconut oil, lauric acid, fish oil, chicken fat 1#, chicken fat 2#, lard 1#, and lard 2# (P>0.05). However, there was a significant difference in gross energy determination results for palm oil (P<0.05) and for lecithin (P<0.001). The suitable sample mass range was 0.6 g to 0.8 g. No significant differences were observed in the gross energy determination results of coconut oil, palm oil, soybean oil, lauric acid, and lecithin when using two different oxygen bomb calorimeters with the same sample mass (P>0.05). Under the conditions of this experiment, there is no need to add a matrix for oil gross energy determination experiments. The method used in this experiment has a stable gross energy determination result and good repeatability. The influence of different sample masses on gross energy results is insignificant for nine types of fats and oils (such as soybean), and the suitable sample mass range was 0.4 g to 1.0 g. Meanwhile, palm oil shows significant difference and lecithin shows extremely difference while the suitable sample mass range was 0.8 g to 1.0 g. There are no significant differences in gross energy results between two different oxygen bomb calorimeters. [ABSTRACT FROM AUTHOR]

Among renewable energy sources, hydrogen and methane are gaseous fuels that have a higher energy density than petroleum-derived gasoline and diesel. In recent years, there has been increasing interest in converting existing anaerobic digestion systems to a two-stage process that produces hydrogen in the first stage and then methane in the second stage and is characterized by increased recovery of biofuels and bioenergy. In this study, an assessment of the energy recovery from two-stage mesophilic-thermophilic anaerobic digestion of cheese whey (CW) was carried out. After appropriate dilution, CW was fed at three COD levels of 6.8, 9.2 and 13.8 g O 2 /L to a mesophilic acidogenic reactor with a hydraulic retention time (HRT) of 10 h. The acidogenic reactor effluent was then fed to three thermophilic methanogenic reactors, which operated at different HRTs: 72, 48, and 24 h. Polyurethane foam was used to immobilize the anaerobic acidogenic and methanogenic sludge. The heating value (HV) was determined according to the experimental method using a bomb calorimeter for modes with the highest methane content and with the highest hydrogen content, as well as a calculation method based on the content of combustible gases in biohythane. The obtained deviations of the calculated from the experimentally determined HV of biohythane (4.84–7.60%) may be due to the fact that the HV of biohythane is probably not equal to the sum of the HV of pure hydrogen and methane. While an increase in the hydrogen content in biohythane leads to a decrease in the deviation of the calculated HV of biohythane from the experimental one. The maximum energy production rate was 53.2 kJ/(L d) at a COD level of 13.8 g O 2 /L, HRT in an acidogenic reactor of 10 h, and HRT in a methanogenic reactor of 48 h. The maximum energy yield of 14.42 kJ/g COD was obtained at a COD level of 9.2 g O 2 /L, HRT in an acidogenic reactor of 10 h and HRT in a methanogenic reactor of 72 h. [ABSTRACT FROM AUTHOR]

Biomass solid waste (BSW) generation in Malaysia is rapidly increasing as a result of nation’s industrialization, urbanization, and population growth. Thermochemical conversion of BSW to produce energy is not straightforward due to fuel’s high moisture content, low heating value, and poor grindability. Accessing different combinatorial scheme of BSW may help to mitigate above-mentioned issues while maintaining attractively high energy outputs. In this work, calorific values and ultimate analyses of a wide variety of BSW reported in literature were compiled. Based on the collected data, two empirical correlations to predict high heating value (HHV) of BSW were developed using a multiple regression method. The developed correlations were (i) HHV = 908.37C + 2942.94H + 4439.73S + 518.92O − 63558.52(municipal solid waste) and (ii) HHV = 382.62C − 368.16H + 2788.24S − 37.83O + 926.26(biomass/biochar) where, C, H, O, N, and S represent biomass content in a form of elemental carbon, hydrogen, oxygen, nitrogen, and sulfur, respectively. The accuracies of the correlations were verified by comparing the predicted values with those experimentally determined. Thermogravimetric analysis was used to analyze BSW combustion behavior and retrieve important combustion parameters. The best-fit correlations obtained in this work had R2 values of 0.98 (MAPE of 3.2%) and 0.92 (MAPE of 7.1%) for municipal solid waste and biomass/biochar samples, respectively. Moreover, the correlations were fairly accurate in predicting HHV of different BSW combination with prediction error of less than 15%. The correlations developed in this work could be instrumental for a precise determination of different combination of solid biomass.

A precise and accurate energy production quantification, particularly at the individual tree level is needed to understand the potential contribution of eucalyptus plantations to renewable energy development. However, measuring energy storage with a destructive method is inefficient because it requires a large amount of resources. The development of allometric equations is a realistic solution to solve this problem as it facilitates the efficient estimation of energy production from trees. Therefore, this study aims to develop an allometric equation for estimating the energy production of Eucalyptus urophylla in dryland ecosystems in East Nusa Tenggara. The destructive sampling was carried out on 25 sample trees which are evenly distributed from small to large dimensions, while the calorific value of each tree component was analyzed using the bomb calorimeter method. Furthermore, the energy production of each tree was counted by multiplying the calorific value with the total biomass accumulation. To develop an allometric equation, the analysis of regression was applied using several independent variables, such as diameter at breast height (D), combined squared diameter of breast and tree height (D2H), as well as D and H separately. The results showed that the energy production of E. urophylla at the study site varied from 252.56 to 7,813.30 MJ tree-1 with more than 90% accumulated in the stem, followed by foliage (4.62%) and branches (4.05%). The higher the tree dimension, the greater the energy production. Moreover, the equation lnŶ = lna + b.lnD + c.lnH was the best allometric model to estimate energy production with an accuracy of 95.2%. Based on the results, the allometric equation provides an accurate estimation of energy production in E. urophylla.

Following recent developments in micro-scale energy systems, such as microthruster and igniters among others, there is now considerable interest in using tertiary nanothermites to meet the increasing demand in high energy density propulsion systems. The first objective of this research is to compare and analyze the thermal behaviour of different nanothermite tertiary compositions based on nano-aluminium (n-Al), graphene oxide (GO), various salt and metallic oxidizers. The second objective is to identify the thermite reaction mechanism through correlations with the activation energy and exothermic peaks. Thermogravimetry analysis coupled with a differential scanning calorimeter (TGA/DSC) was employed to elucidate the reaction process of these nanothermite compositions, while bomb calorimetry was used to measure their heat of combustion. The apparent kinetics parameters were calculated using Kissinger and Ozawa approaches. The results demonstrate that the addition of GO enhances the reactivity of nanothermites with both salt and metallic oxidizers by reducing the reaction onset temperature, activation energy and increasing the heat release. For nanothermites with oxidizing salts, the heterogeneous solid–gas reaction mechanism plays a more important role than the condensed phase reactions. In general, nanothermites based on oxidizing salts are more reactive than those with metallic ones, as indicated in both theoretical and experimental data. Among them, the GO/Al/KClO4 nanothermite exhibits the highest heat release (9614 J g−1), while the GO/Al/K2S2O8 nanothermite shows the lowest onset temperature and activation energy (380 °C and 105 kJ mol−1). This study provides benchmark information for optimizing the tertiary nanothermites design, use, storage and handling. [ABSTRACT FROM AUTHOR]

In order to promote the use of biomass, we derived an equation for estimating the calorific value of biomass solid fuel with varying water content, taking into account the presence or absence of ash and its amount. The usefulness of the derived estimation equation of calorific value was verified using sugi sawdust and fermented poultry manure samples. As a result, the estimated gross calorific value obtained from the estimation equation of calorific value derived using the measurement results of sawdust and poultry manure in the initial condition agrees very well with the gross calorific value of the samples with and without ash, whose water content was changed by drying sawdust or pelletizing poultry manure. From the above results, the usefulness of the derived estimation equation of calorific value was demonstrated, and using this equation, it was clarified that the gross calorific value of the biomass solid fuel at any water content could be estimated. In addition, by using the derived estimation equation of calorific value for the gross calorific value of the sawdust sample on a dry/ash-free basis and the ash content ratio of the poultry manure sample on a dry basis, the gross calorific value of the fermented poultry manure at any water content could be estimated to some extent. [ABSTRACT FROM AUTHOR]

Thermal processing of aluminum (Al) particles such as annealing followed by rapid quenching had been previously shown to affect single metal particle burning rates. This study extends single particle combustion to a global material-based energy exchange model. Experiments were designed to investigate the global energy exchange resulting from Al powder suspensions processed to induce different (fast and slow) burning regimes. Thermally processed and untreated Al particles were reacted as suspended powder in a closed bomb calorimeter. The calorimeter monitored the transient temperature changes resulting from energy release upon powder combustion. The product residue was analyzed for species concentration using X-ray diffraction. Results link the phase fractions of the aluminum oxide combustion products with global radiant fluxes in the calorimeter system. Metastable alumina associated with nano-oxide formation is in substantially higher concentration for thermally processed powder reactions and also produces greater energy transfer rates. The increased energy transfer rates correspond to higher radiant energy emission which may result from condensation energy associated with nano-oxide particle formation. This study qualifies condense-luminescence as a means for increasing the energy release rates of aluminum particles. By strategically altering metal fuels to control formation of nano-oxide particles upon combustion, appreciable increases in the radiant energy flux can transform energy release rates.

A precise and accurate energy production quantification, particularly at the individual tree level is needed to understand the potential contribution of eucalyptus plantations to renewable energy development. However, measuring energy storage with a destructive method is inefficient because it requires a large amount of resources. The development of allometric equations is a realistic solution to solve this problem as it facilitates the efficient estimation of energy production from trees. Therefore, this study aims to develop an allometric equation for estimating the energy production of Eucalyptus urophylla in dryland ecosystems in East Nusa Tenggara. The destructive sampling was carried out on 25 sample trees which are evenly distributed from small to large dimensions, while the calorific value of each tree component was analyzed using the bomb calorimeter method. Furthermore, the energy production of each tree was counted by multiplying the calorific value with the total biomass accumulation. To develop an allometric equation, the analysis of regression was applied using several independent variables, such as diameter at breast height (D), combined squared diameter of breast and tree height (D2H), as well as D and H separately. The results showed that the energy production of E. urophylla at the study site varied from 252.56 to 7,813.30 MJ tree-1 with more than 90% accumulated in the stem, followed by foliage (4.62%) and branches (4.05%). The higher the tree dimension, the greater the energy production. Moreover, the equation lnŶ = lna + b.lnD + c.lnH was the best allometric model to estimate energy production with an accuracy of 95.2%. Based on the results, the allometric equation provides an accurate estimation of energy production in E. urophylla. [ABSTRACT FROM AUTHOR]

Much attention has been directed toward the development of new energetic materials to achieve the increasingly demanding performance of high‐speed propulsion systems. Nanothermite is one of the main approaches for the development of new energetic materials by the close integration of oxidizer and metal fuel. This study is devoted to evaluating the impact of different carbon nanomaterials (graphene oxide, reduced graphene oxide, carbon nanotubes, and carbon nanofibers) on the thermal behavior of nanothermites based on potassium perchlorate and nano aluminium powder. Nanothermite compositions were prepared using a conventional sonication method. The morphology of nanothermites was characterized by a scanning electron microscope (SEM) coupled with energy dispersive spectroscopy (EDS), which confirmed that the nanoparticles are homogeneously dispersed without agglomeration. The structure of nanothermite was also characterized by Fourier Transform Infrared Spectroscopy (FTIR), X‐ray diffraction (XRD), and Raman spectroscopy. The impact of carbon nanomaterials on the combustion behavior of nanothermite was evaluated by thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), and bomb calorimetry. There was good agreement between results from DSC and bomb calorimetry. In general, the total heat released improved with the addition of carbon nanomaterials and particularly graphene oxide, which generated the highest increase in the heat of combustion. In addition, the maximum decomposition temperature shifted to a lower temperature, which indicates enhanced ignition characteristics. This is the first time reporting on the synthesis and characterization of tertiary nanothermites based on nano‐aluminum, potassium perchlorate, and carbon nanosize materials. It can be concluded that these novel nanothermite compositions exhibit dramatically improved properties as demonstrated by a 200 % increase in the heat of combustion with only a 5 % addition of graphene oxide. Moreover, the ignition temperature decreased from 545.1 °C to 508.7 °C enhancing the overall combustion characteristics. [ABSTRACT FROM AUTHOR]

This study seeks to evaluate the flame-retardant characteristics of experimental particleboard manufactured from coconut fibre using modified potato starch as a green binder. The coconut fibre was used as a replacement for the wood as a raw material in particleboard production. The adhesives used in the process were made by modifying potato starch with citric acid and glutardialdehyde. No flame-retardant additive was added during the processing, and this was done to evaluate the flame-retardant potential of the experimental coconut fibre-based particleboards. The limited oxygen index (LOI) test, the bomb calorimetry, the differential scanning calorimetry (DSC) and the dynamic mechanical analysis (DMA) were used to evaluate the thermal properties and flame retardancy rate of such particleboards. The result of the DMA showed that the coconut fibre-based particleboards had good storage modulus with heat. The bomb calorimeter and LOI results also supported the flame-retardant performance of the panels. Based on the evaluations, it could be prescribed that the coconut fibre particleboard made with citric acid modified potato starch (CAMPS) exhibited the best flame-retardant properties. [ABSTRACT FROM AUTHOR]

In The Present Study, Heat Of Combustion (A He) Values Are Calculated For Energetic Matc.Rials (Em'S) Pellets Based On Ammonium Perchlorate (Ap), Ammonium Dinitramide (Adn) And Potassium Dinitramide (Kdn) Using Abombcalorimeter Unit. Adn, Kdn, And Ap Were Mixed With Carbon Black (Cb) In Various Ratios For Preparing Em'S Pellets. Two Set Of Experiments Were Performed For Evaluating A He For Prepared Pellets. In The First Set Of Experimentation, Pellets Made From The Mixtures Of Adn, Ap, And Cb In Different Ratios Were Used, While In The Second Set Of Experimentation, Pellets Made From The Mixtures Of Kdn, Ap, And Cb In Different Ratios Were Used. In All The Formulations, Cb Acts As An Organic Fuel And As A Catalyst, While The Ap, Adn, And Kdn Act As Oxidizer Entities. The Pellets Were Prepared Using A Pellet Maker Provided With The Bomb Calorimeter Unit. It Was Observed That Pure Adn/Cb Pellet Did Not Burn, While Pure Kdn/Cb Pellet Did Not Burn. Further, Pure Ap/Cb Pellet Produces The Highest Ah As Compared To Other Prepared Em Pellets. [ABSTRACT FROM AUTHOR]

Rice husk is biomass that can be utilized as fuel for biomass gasification as a renewable energy source. In this paper, thermochemical methods were used to determine the higher heating values, moisture content, bulk density, pellet density, microstructure, and elemental composition of Thai Rice Husk (Oryza Sativa Linn). The heating energy was analyzed using a bomb calorimeter, which showed a higher heating value of 15.46 MJ/kg. Determination of pellet density through rice husk powder pelletization exhibited a value of 1.028 g/cm3, while moisture content was 5.017 wt%. The heating value and moisture content revealed good agreement with the literature values, indicating the potentiality of rice hush for energy generation. Scanning electron microscopy (SEM) showed that the raw rice husk and its ash have similar porosity types but different bulk structure. Elemental analysis using energy dispersive X-ray (EDX) indicated that rice husk contains O, Si, C while O and C percentages were drastically decreased during combustion. The obtained heating value and moisture content proved that rice husk could be used as a bio-energy source in biomass gasification for power generation. [ABSTRACT FROM AUTHOR]

In order to improve the energy efficiency of composite nano-metal materials, the energetic intermolecular complexes Si@PVDF/CL-20 with different silicon content (20%, 30% and 40%)were prepared by electrostatic spray method. The heat of combustion of PVDF/CL-20 composites with different ratios was obtained by bomb calorimeter. The morphology of PVDF/CL-20 composite was clarified by using SEM. The effect of Si content on the morphology of Si@PVDF/CL-20 composite particles was also analyzed. The thermal behavior of energetic compounds with different silicon content was studied by DSC-TG, and the kinetic paramters of thermal decomposition were calculated. The thermal analyses indicate that when the PVDF/ CL-20 mass ratio is 1-6, the heat of combustion reaches a maximum value, which can be used as the optimal ratio incoating of nano-Si powder. The SEM results show that when the silicon content is 30%, the composite particles (Si-30% ©PVDF/CL-20) exhibite the best sphericity. The DSC results show that when the silicon content is 20%, a runaway chemical reaction was likely occurred. The effect of Si powder on the decomposition of PVDF/CL-20 composite plays less significant role with the increase of content. The apparent activation energies of Si@PVDF/CL-20 composites calculated by Friedman method are 470. 6, 182.1, 91.7kJ/mol, respectively. The complex decomposition process of Si-20% @PVDF/CL-20 cannot be described by a single kinetic model, whereas those of Si-30% ©PVDF/CL-20 and Si-40% ©PVDF/CL-20 can be well described by a nuclea-tion and growth model. [ABSTRACT FROM AUTHOR]

The current study analyzed the high heating values (HHVs) of various waste biomass materials intending to the effective management and more sustainable consumption of waste as clean energy source. Various biomass waste samples including date leaves, date branches, coconut leaves, grass, cooked macaroni, salad, fruit and vegetable peels, vegetable scraps, cooked food waste, paper waste, tea waste, and cardboard were characterized for proximate analysis. The results revealed that all the waste biomass were rich in organic matter (OM). The total OM for all waste biomass ranged from 79.39% to 98.17%. Likewise, the results showed that all the waste biomass resulted in lower ash content and high fixed carbon content associated with high fuel quality. Based on proximate analysis, various empirical equations (HHV=28.296-0.2887(A)-656.2/VM, HHV=18.297-0.4128(A)+35.8/FC and HHV=22.3418-0.1136(FC)-0.3983(A)) have been tested to predict HHVs. It was observed that the heterogeneous nature of various biomass waste considerably affects the HHVs and hence has different fuel characteristics. Similarly, the HHVs of waste biomass were also determined experimentally using the bomb calorimeter, and it was observed that among all the selected waste biomass, the highest HHVs (21.19 MJ kg−1) resulted in cooked food waste followed by cooked macaroni (20.25 MJ kg−1). The comparison revealed that experimental HHVs for the selected waste biomass were slightly deviated from the predicted HHVs. Based on HHVs, various thermochemical and biochemical technologies were critically overviewed to assess the suitability of waste biomass to energy products. It has been emphasized that valorizing waste-to-energy technologies provides the dual benefits of sustainable management and production of cleaner energy to reduce fossil fuels dependency. However, the key bottleneck in commercializing waste-to-energy systems requires proper waste collection, sorting, and continuous feedstock supply. Moreover, related stakeholders should be involved in designing and executing the decision-making process to facilitate the global recognition of waste biorefinery concept. [Display omitted] • The high heating values (HHVs) of biomass waste were assessed with the aim for the sustainable consumption of waste as a source of clean energy. • All the biomass waste were rich in organic matter and fixed carbon content that ranged from 79.39% to 98.17% and 50.64%–54.26% respectively. • The maximum HHVs (21.19 MJkg−1) were recorded for cooked food waste. • The heterogeneous nature of various biomass waste considerably affects the HHVs and hence serve as suitable feedstock for various energy conversion technologies. [ABSTRACT FROM AUTHOR]

[Display omitted] • Empirical models of heating values from literature lead to large errors for mixed garden waste. • Bomb calorimetry is the preferred method for accurately determining higher heating values (HHV). • Ash content (AC) can be measured directly as part of bomb calorimetry for mixed garden waste. • AC of mixed garden waste was a better predictor of HHV than parameters from elemental analysis. • AC and HHV can be measured accurately and simultaneously using bomb calorimetry. Two of the most important properties of a material to determine its suitability as a waste-to-energy feedstock are its calorific content and ash content (AC). In the literature, it has been widely suggested that using the results from ultimate and proximate analysis to determine the former through empirical models is an accurate method that saves time and reduces labor. In this work we evaluated the suitability of these models for mixed garden waste using samples collected from two geographical distinct municipal waste disposal sites. It was found that when the models, with parameters given in the literature, are used, the errors in the estimates of higher heating values (HHV) could be higher than acceptable limits. Using linear regression, we determined the model parameters for our specific feedstocks based on the measured elemental, AC and the HHV values from a bomb calorimeter that reduced this error, with AC being the best predictor. However, there were still points with errors over 15%, indicating that these empirical models may not be suitable for the highly varying biomass characteristics typical of mixed green waste feedstocks and that direct measurement through bomb calorimetry still provides the most accurate results. We did find though, that the residues from bomb calorimetry could be used to determine the ash content of mixed garden waste as a time-, labor- and energy-saving measure. Standards for ash content measurements involve the use of a furnace. Here we compared two standard procedures to each other and to the bomb calorimeter residue. Statistical analysis explicitly showed for the first time that we are aware of, that the residue of mixed garden waste from bomb calorimetry tests provided a reliable estimate of ash content over a large range with agreement within 10 % to standards and therefore can be used in place of the standards thereby significantly reducing the time and cost of the tests while getting more accurate results for HHV compared to the models suggested in the literature. [ABSTRACT FROM AUTHOR]

In order to obtain the chemical reaction mechanism of Al-rich Al/PTFE/TiH2 composites in argon and oxygen atmosphere, Al/PTFE, PTFE/TiH2, Al/TiH2 and Al-rich Al/PTFE/TiH2 with different contents of TiH2 composites were prepared by using the wet mixing method. The pyrolysis behavior of the above composites was investigated by thermogravimetric differential scanning calorimeter (TG-DSC). In addition, the calorific value of the above composite was measured by an oxygen bomb calorimeter. The compositions of TG-DSC residues at different peak temperatures and 1000 °C and the residues of oxygen bomb experiment were analyzed by X-ray diffraction (XRD), The results show that the pyrolytic products of Al-rich Al/PTFE/TiH2 materials under argon atmosphere can be divided into four stages. In the first stage (328.6–378.6 °C), the products are TiH1.924, (C2F4)n, (CF2)n, H2(g), Al and TiH2; in the second stage (510.8–534.3 °C), the products are Al, TiH1.924, (C2F4)n, (CF2)n, Ti, AlF3, TiF3, TiF4(g), C and H2(g). In the third stage (540.8–618.1 °C), the products are Al, C, Ti, (C2F4)n, (CF2)n, AlF3, TiF3, TiF4, CF4(g), C3F6(g), C4F8(g), C2F6(g), Al5Ti2 and H2(g); in the fourth stage (918.5–1000 °C), the products are AlCTi2, Al2Ti, AlTi, TiC, AlF3, Al, TiF3, TiC0.957, TiC0.981 and TiC0.95. The calorific value of the combustion of Al-rich Al/PTFE/TiH2 composite with 10% the content of TiH2 is the highest and is 19,899 J/g, which is 3.776% higher than that of Al-rich Al/PTFE composite. When TiH2 content is greater than zero and not more than 10%, the chemical reaction mechanism of Al-rich Al/PTFE/TiH2 is almost the same under oxygen atmosphere. When the content of TiH2 is higher than 10%, the mechanism of this material is different.

Increasing fuel and liquid gas prices make this energy source is no longer cheap. Therefore, it is necessary to create an alternative energy resource that can be used to replace the role of fuel and gas. Waste sawdust and coconut shell has a huge potential that can be used as raw material charcoal briquettes. The purpose of this research is to improve the quality of sawdust briquettes with the addition of coconut shell charcoal. To improve the quality of charcoal briquettes, the addition of coconut shell charcoal with a variation of 20%, 30%, 40%, 50% and 60% of the weight of sawdust briquette charcoal. Authoring process is done by burning coconut shells directly and roasting methods to sawdust. Adhesives are used as much as 50%. The calorific value generated in sawdust briquettes with materials: coconut shell at a concentration of 100% is 5622.7769 cal/gram, a concentration of 80: 20% is 6504.67785 cal/gram, the concentration of 70: 30% is 6624.09305 cal/gram, the concentration of 60: 40% is 7017.5178 cal/gram, a concentration of 50: 50% is 7288.7523 cal/gram and 40: 60% is 7386.4805 cal/gram. Overall, the quality of sawdust briquettes with palm shell charcoal is quite good, so it can be used as an alternative fuel

This scientific study deals with investigation of the heat of combustion and effective heat of combustion of selected electrical cables. Two different electrical cables for rated voltage of 0.6/1 kV were investigated. Both cables were power three-core with cross-section area of each core of 1.5 mm2. The cores of both cables were made of a bar cooper wire. Insulations of conductors of both cables were made of silane cross-linked polyethylene without any inorganic filler, while the bedding and outer sheath were made of polyethylene-based copolymer (the beddings were filled with two fillers - aluminium hydroxide and calcium carbonate, while the outer sheath were filled only with aluminium hydroxide). Reaction to fire class of both cables was B2ca, s1, d0, a1. The main difference in the investigated cables was that the core of one of them was wrapped in a glass mica tape (this cable showed circuit integrity maintenance under fire conditions during 180 minutes). The heat of combustion and effective heat of combustion were determined by the oxygen bomb calorimeter according to the ISO 1716:2018 standard. The highest effective heat of combustion showed the insulation of wires (for both cables 42.47 ± 0.03 MJ/kg), lower value showed outer sheath (interval form13.61 to 15.26 MJ/kg) and the lowest value was determined for bedding (interval from 4.69 to 6.39 MJ/kg). The effective heath of combustion per unit of length of both investigated cables lies in the interval from 1.37 to 1.38 MJ/m. Therefore, there is no significant difference in effective heats of combustion of the electrical cables investigated. [ABSTRACT FROM AUTHOR]

The investigation of the possibility to optimize ballistic behavior and consequently to obtain better performance without affecting the cost and safety aspect of plastisol propellants has been presented in this paper. Addition of specific additives and changes in particle size can be one of these solutions, which are continuously in research. The use of burn rate modifier and metallic fuel, with finer particle sizes, becomes mandatory, to enhance the catalytic effect on ammonium perchlorate and to offer additional high heat release. Moreover, the knowledge of the combustion characteristics and especially the burning rate depending on the combustion chamber pressure of the propellant are important conditions in the validation and successful design of a solid rocket motor. The first part of this work deals with the selection of the higher energetic catalyst among three of the most common of them, namely copper chromite, ferric oxide and ferrocene. The selection results in choosing copper chromite as the best burning catalyst. Then, we have studied the effect of its particle size on the thermoanalytical properties of poly(vinyl-chloride) plasticized propellants, by the determination of energetic and kinetic characteristics through the use of an adiabatic bomb calorimeter and a differential scanning calorimeter respectively. The kinetic parameters were determined by Ozawa and Kissinger methods and compared. Besides, the effect of particle size on the combustion properties has been also studied. The plot of the burning rate-pressure curves is used to determine the combustion laws using a strand burner in the typical Crawford bomb. Copper chromite and its particle size have been found to influence the decomposition and to enhance the burning rate of the plastisol propellants. In the second part, we have investigated the energetic effect of fine aluminum powder on the thermal decomposition of ammonium perchlorate and of plastisol propellant as a function of its concentration, both in the presence and the absence of 1 mass-% copper chromite in the basic propellant composition. Aluminum is chosen because of its effect to get high flame temperatures and increased performance. [ABSTRACT FROM AUTHOR]

Mathematical models for estimating the higher heating value of coals have constantly been developed and verified. Recently, models based on proximate analysis have gained much attention because of the relative ease in acquiring of such data. However, most models reported are focused solely in improving the accuracy of the estimates and oftentimes the realistic physical explanation and assumptions of the model are not looked into. Furthermore, most models found in literature are generated from coals of specific origin and thus limiting its applicability. In this work, a simple linear additive model with moisture, fixed carbon, volatile matter and ash as parameters was generated. In the generation of the model, proximate data sets (n > 8000) of coals form various origins was taken into consideration having higher heating values ranging from 0.09 to 36.26 MJ/kg. A plausible derivation of a model based on energy and material balance is also provided. The proposed improved model outperforms similar models reported in literature and has a comparable accuracy when compared to complex model previously established. Abbreviations: ar: as received db: dry basis daf: dry-ash-free basis FC: fixed-carbon HHV: higher heating value VM: volatile matter [ABSTRACT FROM AUTHOR]

We have first demonstrated the cooperation between an X-ray TES and a directly coupled microwave SQUID multiplexer (D-coup. MW-Mux) in which SQUIDs are directly coupled to resonators. Using D-coup. MW-Mux, we successfully detected the X-ray pulses from a single-pixel TES and evaluated the energy resolution of 11.8 eV FWHM at 5.9 keV. We found this preliminary energy resolution is attributed to non-optimum bias point of the present TES, which can be improved by the future reduction of readout noise. [ABSTRACT FROM AUTHOR]

We are developing transition edge sensor (TES) X-ray microcalorimeters for the future Japanese mission DIOS. It adopts microstrip readout wiring for low pixel-to-pixel crosstalk. In past samples, TES films composed of Ti and Au have not shown proper super-normal transition when it is deposited on the wiring. Assuming that surface roughness of the substrate can influence the transition, we reduced the surface roughness of the underneath layer before deposition of the TES film by using chemical mechanical polishing. We then found that the substrate becomes much smoother with a roughness of <1 nm rms and the TES film shows a proper transition. [ABSTRACT FROM AUTHOR]

We consider how to analyze microcalorimeter pulses for quantities that are nonlinear in the data, while preserving the signal-to-noise advantages of linear optimal filtering. We successfully apply our chosen approach to compute the electrothermal feedback energy deficit (the “Joule energy”) of a pulse, which has been proposed as a linear estimator of the deposited photon energy. [ABSTRACT FROM AUTHOR]

Energy used for domestic application are expensive and beyond the reach of the rural poor. An alternative energy source is therefore a welcome development. This research work was aimed at determining the calorific values of Corn cob, Rice husk and Sawdust agricultural wastes materials. Standard method of calorific value determination involving the use of Bomb Calorimeter was adopted. From the investigation, the calorific value of Rice husk, Sawdust and Corn cob are 2938.86 Kcal/kg, 3155.30 Kcal/kg and 3227.78 KcaI/kg respectively. The agricultural materials were further subjected to briquetting and the calorific values determined to be 2092.48Kcal/kg, 2379.76Kcal/kg and 2923.36Kcal.kg for Rice husk, Sawdust and Corn cob briquettes respectively. The agricultural wastes met the minimum standard calorific value which range from 1500cal/kg - 1670Kcal/kg. The selected wastes have calorific values in the following decreasing order: Corn cob> Sawdust> Rice husk; and the corresponding briquettes is in the order: Corn cob>Sawdust >Rice husk. The selected wastes however, have lesser calorific values when briquetted. If agricultural wastes are used in place of firewood, this development will minimize deforestation which leads to desert encroachment and soil degradation. [ABSTRACT FROM AUTHOR]

Dietary studies have long shown that insectivorous bats do not often consume mosquitoes, despite cosmopolitan distribution and occasional ubiquity of mosquitoes (Culicidae). The apparent avoidance of mosquitoes relative to availability may relate to their small size, as bats may have difficulties detecting and capturing mosquitoes or they may not return sufficient energy per unit effort of capture. We used bomb calorimetry to determine the energetic content of mosquitoes from Alaska and Illinois, USA, and compared resulting estimates to daily energy expenditure of several bat species. On a per gram basis, mosquitoes were energetically comparable with other insects (26.82 ± 2.40 kJ/g dry mass); however, an individual mosquito contains little energy. Some small insectivorous bats could theoretically meet daily energy needs by foraging exclusively on mosquitoes for <2 h, assuming maximal estimates of the rate of successful capture of mosquitoes. Larger, omnivorous bats may require >25 h of foraging on mosquitoes to meet daily energy needs. Wet mass of the mosquitoes required to balance energy budgets represent 18%-92% of body mass of bats and tends to be higher for smaller species. Thus, it appears that a mosquito-based diet may be constrained by different factors in small and large bat species. [ABSTRACT FROM AUTHOR]

Specific energy of combustion of vanillin was determined using the bomb calorimeter BIC 100 with high degree of thermal protection from environment impact. The standard deviation of mean for energy equivalent was 0.01%. Based on the specific energy of combustion −(25,072.1 ± 7.4) J g−1, the standard molar enthalpy of combustion and standard molar enthalpy of formation for vanillin in the crystalline state at 298.15 K were calculated to be −(3815.9 ± 1.1) and −(475.5 ± 1.5) kJ mol−1, respectively. Standard molar enthalpy of formation of vanillin in the gaseous state was determined to be −(375.8 ± 2.1) kJ mol−1 from ab initio calculations using density functional theory and G3 methods. The enthalpy of sublimation of vanillin at 298.15 K, determined as difference between standard molar enthalpies of formation of vanillin in crystalline and gaseous states, was found to be 100 ± 3 kJ mol−1. [ABSTRACT FROM AUTHOR]

• Magnesium particles show limited combustion completeness. • Vapor phase reactions condense oxide products on particle surface. • Condensation on surface encapsulates unreacted metal. • Unburnt and encapsulated metal core limits further oxidation. There is a natural abundance of carbon dioxide in the Martian atmosphere that can oxidize magnesium fuel. Combustion of magnesium carried from Earth is considered as a potential propulsion process for Mars Ascent Vehicles. Other space exploration missions would benefit from magnesium combustion and thus sparked motivation to resolve puzzles in existing models for metal combustion. Harnessing all the chemical potential energy available in a metal particle will optimize power generation capabilities and payload demands. Here we design experiments to quantify metal combustion completeness, an important parameter that characterizes propulsion performance. Results show reduced energetic performance of magnesium combustion is directly related to the unavoidable occurrence of unburnt metal encapsulated in the combustion products caused by condense-luminescence. The new data provide insight into the advanced physics controlling metal particle combustion. The analyses suggest a path to improve magnesium energetic output by controlling radiative loss. [Display omitted] [ABSTRACT FROM AUTHOR]

Currently there is a need for specialized pyrotechnic materials to combat the threat of biological weapons. Materials have been characterized based on their potential to produce heat and molecular iodine gas (I2) to kill spore-forming bacteria (e. g. anthrax). One formulation, already proven to kill anthrax simulants, is diiodine pentoxide with aluminum; however, it suffers from poor stability and storage problems. The heat and iodine gas output from this mixture and candidate replacement mixtures were measured with bomb calorimetry and extraction and analysis of I2 by UV-Vis. Of the mixtures analyzed, calcium iodate and aluminum was found to be the highest producer of I2. The heat output of this mixture and others can be tuned by adding more fuel, with the cost of some iodine. Products of combustion were analyzed by thermal analysis (SDT), XPS, XRD, and LC/MS. Evidence for various metal iodides and metal oxides was collected with these methods. [ABSTRACT FROM AUTHOR]

Bio-Methane Potential (BMP) tests are used to evaluate the suitability of a biomass for anaerobic digestion. BMP data are usually presented as the amount of methane produced from a kilogram of volatile solids (VS) or chemical oxygen demand (COD) of the substrate. However, the most used methods for determination of VS and COD are not always accurate. Oven drying may underestimate VS content due to loss of volatile organic compounds, and incomplete chemical oxidation may lead to underestimation of COD content. Bomb calorimetry is an attractive alternative to COD measurements, because the physical state of the biomass sample does not influence the measurement, and because sample preparation is limited. In this study, 11 biomass samples, wet and dry, were analyzed with different methods for organic content determination. COD (determined by bomb calorimetry and by wet chemistry) and VS (by Karl Fischer titration and loss on drying; LOD) were compared, and used for determination of BMP. In general, the BMP estimated on a VS basis were higher than those estimated on COD basis. For certain biomass samples the method for VS determination also greatly influenced the results; for fishery waste the BMP was estimated as 928 L kg −1 based on LOD-VS compared to 394 L kg −1 based on KF-LOD. Thus, this study shows that determination of organic content is not trivial and the method of choice strongly influences the estimation of bio-methane potentials. Bomb calorimetry offers a possibility to measure energy content directly, independent of biomass composition and physical state. [ABSTRACT FROM AUTHOR]

Thirty weaned Large White Yorkshire (LWY) piglets were randomly divided into three groups and were allotted to the three dietary treatments, T1 (control ration as per NRC, 1998), T2 (50 per cent of maize of control ration replaced by wheat bran) and T3 (100 per cent of maize of control ration replaced by wheat bran). Digestibility trial was conducted following total collection method and gross energy was estimated using bomb calorimeter. The estimation of gross energy of feed and faeces were reported. [ABSTRACT FROM AUTHOR]

Non-combustibility is discussed on the basis of experimental data for 66 commercial building materials obtained from two standard test methods: EN ISO 1716 oxygen bomb calorimeter and EN ISO 1182 cylindrical furnace. The sample materials are divided into five categories: concrete and ceramics, thermal/acoustic insulation materials, wall or ceiling boards, mortars and adhesives and thin coatings. To better distinguish between non-combustible and combustible materials, an effective modified heat of combustion is defined and calculated for all materials tested in both methods. The materials studied exhibited very different mass loss values and a low tendency to auto-ignite in the cylindrical furnace. Revised criteria for class A1 are proposed for better accuracy of reaction-to-fire assessment. It is proposed to use the oxygen bomb calorimeter with only one limit for the heat of combustion, that is, a value of 5 MJ/kg for all materials. The proposed approach is a very efficient tool for fast and inexpensive screening for non-combustibility of building products and is expected to be a more precise method to distinguish between non-combustible and combustible materials. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The energy released by failure of rechargeable 18-mm diameter by 65-mm long cylindrical (18650) lithium ion cells/batteries was measured in a bomb calorimeter for 4 different commercial cathode chemistries over the full range of charge using a method developed for this purpose. Thermal runaway was induced by electrical resistance (Joule) heating of the cell in the nitrogen-filled pressure vessel (bomb) to preclude combustion. The total energy released by cell failure, Δ H f , was assumed to be comprised of the stored electrical energy E (cell potential × charge) and the chemical energy of mixing, reaction and thermal decomposition of the cell components, Δ U rxn . The contribution of E and Δ U rxn to Δ H f was determined and the mass of volatile, combustible thermal decomposition products was measured in an effort to characterize the fire safety hazard of rechargeable lithium ion cells. [ABSTRACT FROM AUTHOR]