Calorific Energy Research Articles

Second law analysis of Al-Doura Pool Gasoline

A second law analysis for an engine using fuels produced by Al-Doura Oil Refinery. The fuels used were the enhanced pool formulae (called S1 to S4). The engine performance and emission characteristics were studied both from first and second law point of view. Results showed improvement in most of the fuel properties like calorific value, sulfur content, ON, gum content and energy density. On the engine side, the brake power, thermal efficiency (and specific fuel consumption) and sulfur dioxide levels improved, while heat loss and NOx emissions increased. From second law analysis, it is clear that S1 grade showed the highest fuel and indicated work availability compared with others but at the cost of exergy destroyed as heat and entropy generation.

‘Hot topic’ – combined energy and process modeling in thermal hydrolysis systems

The thermal hydrolysis process (THP) is applied to enhance biogas production in anaerobic digestion (AD), reduce viscosity for improved mixing and dewatering and to reduce and sterilize cake solids. Large heat demands for steam production rely on dynamic effects like sludge throughput, gas availability and THP process parameters. Here, we propose a combined energy and process model suitable to describe the dynamic behaviour of THP in a full-plant context. The process model addresses interactions of THP with operational conditions covered by the AD model obeying mass continuity. Energy conservation is considered in balancing and converting various energy species dominated by thermal heat and calorific energy. The combined energy and process model was then applied on the THP at Blue Plains advanced WWTP (DC Water) to analyse the process and assess potential energy optimizations. It was found that dynamic effects like mismatched steam production and consumption, temporary gas shortages and underloaded units are responsible for energy inefficiencies with losses in electricity-production up to 29%.

Термодинамический анализ плазменной газификации отходов сельского хозяйства

Most of the agricultural waste (AW) comes from poultry farms and livestock farms mainly in the form of bird droppings and cattle dung. Irrational use of large volumes of such waste negatively affects the environment. Modern technologies allow utilizing agricultural waste to produce energy gas. Plasma recycling of waste from the agro-industrial complex allows intensifying the process of obtaining energy gas consisting mainly of synthesis gas (СО+Н2) and a 150–200-fold increase in the gas productivity of the plasma gasifier compared with biogas generators. This article is devoted to the thermodynamic modelling of AW plasma-processing. The thermodynamic analysis of the waste plasma processing was performed using the universal program of thermodynamic calculations TERRA. In the work under the AW means the excrement of farm animals (manure). For research, dried mixed manure (dung with 30% moisture content) from cattle is used. Thermodynamic calculations showed that during plasma gasification and pyrolysis of AW, high-calorie combustible gas is produced with a synthesis gas yield of 65.2 and 68.5%, respectively. No harmful components were detected. Plasma gasifier will allow to effectively process various types of AW into high calorific energy gas, consisting mainly of synthesis gas, and into neutral slag. The technological scheme of AW plasma processing has been developed. Using proposed plasma plant that implements this scheme, depending on the composition of the AW, up to 1.7 m3 of dry energy gas can be obtained from 1 kg of AW. At the same time, its caloric content will vary from 8500 to 300 MJ/Nm3. The composition of the energy gas will be following, vol.%: H2 - 35-39, CO - 29-31, CO2 - 4-6, N2 - 10-14, H2O - 13-18. Such gas can be used as a working medium of highly efficient electric generators of a new generation, including solid oxide fuel cells or as a raw material for the production of synthetic motor fuels (methanol, dimethylether)

Agustín de Betancourt’s Double-Acting Steam Engine: Geometric Modeling and Virtual Reconstruction

In this paper, the geometric modeling and virtual reconstruction of the double-acting steam engine designed by Agustín de Betancourt in 1789 are shown. For this, the software Autodesk Inventor Professional is used, which has allowed us to obtain its geometric documentation. The material for the research is available on the website of the Betancourt Project of the Canary Orotava Foundation for the History of Science. Almost all parts of the steam engine are drawn on the sheets, but due to the absence of scale and space, it is insufficient to obtain an accurate and reliable 3D CAD (Computer-Aided Design) model. For this reason a graphic scale has been adopted so that the dimensions of the elements are coherent. Also, it has been necessary to make some dimensional and geometric hypotheses, as well as restrictions of movement (degrees of freedom). Geometric modeling has made it possible to know that the system is balanced with the geometric center of the rocker arm shaft, and presents an energetic symmetry whose axis is the support of the parallelogram where the shaft rests: calorific energy to the left and mechanical energy to the right, with the rocker arm acting as a transforming element from one to the other.

Pyrolysis kinetics of Hibiscus rosa sinensis and Nerium oleander

ABSTRACTPyrolysis is a thermal method in which volatile matter present in a biomass will be degraded to lower molecular substances. This study aims at evaluation of kinetics of lignocellulosic biomass of leaves and stems of Hibiscus rosa sinensis and Nerium oleander under pyrolytic conditions, their proximate and ultimate analyses and their calorific values. Pyrolysis experiments were carried out using a thermogravimetric balance, which combines heat flux type differential thermal analysis (DTA) with thermogravimetric analysis (TGA) at different heating rates under a nitrogen atmosphere. The results were analyzed using weight loss vs. temperature and derivative weight vs. temperature profiles obtained from DTA and TGA curves. Three kinetic stages apart from moisture evaporation were observed based on the type of biomass. Kinetic parameters such as the pre-exponential factor and activation energy for each degradation step were calculated using first-order kinetics. The assumption of first-order kinetics was also proved from the experimental data. The results showed that Nerium oleander leaves are more suitable for fuel production through pyrolysis due to their higher percentage of volatile matter, low sulfur content, lower ash content, higher calorific value and lower activation energy required to decompose constituents of biomass, namely hemicellulose, cellulose and lignin.

Socio-demographic characters, distribution and transformation of iodine in soil, plant and wheat grains at District Diamer, Gilgit-Baltistan, Pakistan.

Iodine deficiency in soils and plants is a common problem in the hilly areas and has still been ignored. The aim of the current study is to investigate associated health issues, socio-economic characteristics and people's perception regarding iodine deficiency. Furthermore, a follow-up study was conducted to determine iodine and nutrients concentration in soil and crops at District Diamer, Gilgit-Baltistan, Pakistan. A descriptive and empirical analysis was examined. Most importantly, male was significantly observed as more affected for iodine deficiency than female, as contrary to the literature, socio-economic factors such as households' income and awareness (education) are reported as negative and significant contributor to reduce the iodine deficiency among the people irrespective of the gender. Majority of people (84%) heard about the iodine, but about 51.6% people argue that iodine has no effect on the human body and 56% of the respondents do not know why iodine is necessary for human. It was found that 11.5% of the community was affected from the IDD and majority of them were females. Wheat crops were the principal crop since it supplies 75% of calorific energy in an average Pakistani diet. The concentrations of iodine in soil samples range from 4.21 to 5.45mgkg-1. The concentration of iodine in wheat crop plant sampled were considerably varied as Boner>Gais>Goher Abad with 1.12, 0.91 and 0.81mgkg-1. respectively. Likewise, grain iodine concentration was varied as Gais>Boner>Goher Abad with 0.126, 0.102 and 0.078mgkg-1, respectively. This study exposed that community using the cereal crops could face iodine deficiency in their diet which can cause endemic goiter among the population and control the iodine deficiency by empowering the rural community to raise the income level and providing the awareness to the people.

Determinants of arctic-alpine pasture resources: the need for a spatially and functionally fine-scaled perspective

ABSTRACTThe current greening of arctic-alpine landscapes poses the question about its underlying ecological mechanisms. Given its importance across various contexts and scales, it is vital to understand the drivers of contemporary patterns in phytomass and primary productivity to improve predictions under altered environmental conditions. Here, we analysed local patterns in above-ground phytomass, calorific energy contents, and primary productivity as important pasture resources in a complex arctic-alpine landscape along pronounced micro-topographical and elevational gradients. Using data from 110 sampling sites, of which 38 were equipped with on-site recordings of soil moisture and near-surface temperatures, we asked how the observed patterns in pasture resources are related to the environment and whether commonly used structural proxies or physiologically relevant, functional data were better suited for their explanation. Using partial least squares regression based on a set of structural plus functional explanatory variables, the latter revealed to be the best determinants. Our results suggest how the ecological mechanisms behind contemporary pasture resources and, likewise, the arctic-alpine greening are interactively driven by the near-surface thermal regime, associated snow coverage, and soil moisture availability. Moreover, they reveal an obvious decoupling of near-surface processes from the overall atmospheric and topographic constraints which are commonly used as proxies. We conclude that estimates of current and future pasture resources would be significantly improved if fine-scaled, functional data, rather than structural data, could be used. However, this implies further effort in providing such data, since appropriate regionalization techniques are still lacking.

Comparison of biochemical compositions of phytoplankton during spring and fall seasons in the northern East/Japan Sea

The East/Japan Sea (EJS) where is surrounded by the Korean peninsula, the Japanese islands, and the Russian coast has been experiencing a large change in physicochemical properties. Based on biochemical composition analysis (carbohydrates, proteins, and lipids), the current qualitative status of phytoplankton was identified in the northern EJS from two different sampling seasons (fall and spring in 2012 and 2015, respectively). The average chlorophyll-a (chl-a) concentration integrated from the euphotic depths was significantly higher in 2015 (99.3 ± 69.2mgm−2) than 2012 (21.5 ± 6.7mgm−2). Large phytoplankton (> 2µm) were predominant in 2015 accounting for 64.5 ± 19.7% whereas small-size phytoplankton (0.7–2µm) were dominant (49.1 ± 17.5%) in 2012. The biochemical compositions of phytoplankton were predominated by lipids (42.6 ± 7.8%) in 2012 whereas carbohydrate composition largely contributed (53.2 ± 11.7%) to the total biochemical composition in 2015, which is mainly due to different nutrient availabilities and growth stages. Interestingly, the averaged FM concentrations and calorific values for phytoplankton based on the biochemical compositions had similar values between the two years, although the integrated chl-a concentrations were substantially different between 2012 and 2015. In terms of different cell sizes of phytoplankton, we found that small phytoplankton assimilate more FM and calorific energy per unit of chl-a concentration than total phytoplankton. Our results are meaningful for the understanding of future marine ecosystems where small phytoplankton will become dominant at a scenario of ongoing warmer oceans.

Seawater provides energy for heating and cooling

France's first marine geothermal power station, the Thassalia project in Marseille, will use the calorific energy of the Mediterranean as a sustainable energy source. A French international pump manufacturer worked with project owner, ENGIE, from the start.

Comment on “The challenge of energy-efficient transportation” J. Hermans

It’s hard to beat the energy density and convenience of liquid hydrocarbons. The product of energy used and journey time is another way to compare transportation systems. It is more practical to power electric cars from batteries than photovoltaics. Solar can be used to supply some of the energy needed to recharge the batteries. The primary energy used to make food, the fuel for the human cyclist, can be many times the calorific energy derived from the food. Transportation is a major source of carbon dioxide emissions. Hermans makes some excellent points in his article “The challenge of energyefficient transportation.” However primary energy to produce fuel should also be considered. The embodied energy of liquid hydrocarbon fuels is much less than their energy content. For a cyclist the fuel is food, and, depending on diet, the primary energy can be many times the food’s calorific energy. The article is over optimistic on the prospect of cars directly powered by solar photovoltaics. It’s more realistic to use batteries in electric cars and generate the electricity from a number of sources. For anything other than trains that run on fixed tracks it’s hard to beat the energy density and convenience of liquid hydrocarbons.

Hot-Water Extraction Optimization of Sugar Maple (Acer saccharum Marsh.) and Red Maple (Acer rubrum L.) Bark Applying Principal Component Analysis

In the forest industry, bark is an abundant residue, predominantly converted into calorific energy. As the antioxidant potential of phenolic compounds from sugar maple (Acer saccharum Marsh.) and red maple (Acer rubrum L.) bark has previously been established, the present study focused on the hot-water extraction optimization of these barks. Several process parameters (maple species, temperature, duration, ratio bark/water, particle size) were thus studied and large disparities were found between the two species. Extraction yield, phenolic content, and antioxidant capacity of red maple extracts were several times higher than those of sugar maple extracts. Principal component analysis, applied to the selected best extraction conditions, identified 3–4 clusters depending on the maple species. These groups were sorted from the highest extraction yield and energy consumption combined with the lowest phenolic content and antioxidant capacity, to moderate extraction yield and energy consumption with the highest phenolic content and antioxidant capacity.

Nutritional profile and phytochemical composition of Gardenia sokotensis (Boscia of the rock)

Plant information are vital to assess and develop nutrition, food security policies, traditional medicine and its significance in the distribution of these chemical constituents, as a result, the nutritional and phytochemical composition of Gardenia sokotensis pulp and seeds were analyzed. The moisture content, ash content, crude lipid, crude protein, crude fibre, calorific energy value and available carbohydrate were analyzed on dry weight bases. All the determinants were carried out in triplicates. The pulp had high value of ash (17.88 ± 0.41%), moisture (21.71 ± 0.00%) and crude lipid (53.96 ± 1.59%) while the seeds had high value of crude protein (13.04 ± 0.47%), crude fibre (17.65 ± 0.14%), carbohydrate (9.67%) and energy value (1445.87Kcal). The anti-nutritional factors for pulp and seeds were phytate (0.14 ± 0.00), (2.30 ± 0.00), oxalate (1.10 ± 0.00), (1.10 ± 0.00), nitrate (0.04 ±0.00), (0.14 ± 0.00), cyanide (0.12 ± 0.00), (0.21 ± 0.00) and tannins (0.21 ± 0.00), (0.27 ± 0.00) respectively and all were within the tolerable level. The results of mineral analysis of the seeds and pulp showed different concentration of the element, Na (106.67 and 85.83), K (5700 and 7666.67), Ca (0.6833 and 0.4333), Mg (0.2500 and 0.8266), Fe (4.2914 and 6.7959), Zn (1.3639 and 0.1522), Cu (1.5298 and 2.1755), Cr (0.0096 and 0.0163), Mn (0.2615 and 0.3101), Pb (0.0594 and 0.0657), Co (0.0447 and 0.1195) and for phosphorus (3.4700 and 10.3000). Phytochemical screening indicated the presence of alkaloid, saponins, steroids, tannins, cardiac glycosides and flavonoids. Based on these results, seeds and pulp of Gardenia sokotensis contains appreciable amount of nutrients and secondary metabolite which could serve as a supplementary source of food and new drug discovery for the benefit of humans and livestock.

Paulownia Tomentosa, a Fast Growing Timber

Abstract The fast growing woody crops are a very important source for the generation of the bioenergetics biomass. Paulownia sp. Is a plant part of this group, and because of its fast growth, multiple values and high adaptability with climate conditions, is set recently in the centre of the intention. Paulownia is one of the fastest growing species in the world with low concentration of ash, sulphur and nitrogen and high calorific energy from its wood. It is considered as an energetic crop adequate for the production of the solid biocarburants and the bioethanol. The cultivation of the Paulownia because of the high absorption of CO2 from the air, to support the fast growth of the biomass, is considered as an effective mean to soften the climacteric changes. The plant is also considered as suitable to improve the abandoned lands when its cultivation is concentrated to the biomass production. The genus of Paulownia (Scrophulariaceae) is autochthones species of China and East Asia and as such is not found naturally in Albania. To study the regionalization possibilities of this species in the Korça climacteric conditions, aiming its cultivation according the fast growth coppice system were planted in 2014 in Cangonj (Devoll) 300 seedlings of P. tomentosa in a distance of 1 x 1 m. during the year 2015 were planted other 400 seedlings prepared with seeds. This article deals with the preliminary data of the regionalization performance of this high energetic value crop.

Measurement of Energy Expenditure on a Smartphone Using a Hand-held Breath Analyser

An indirect calorimeter is presented for measurement of Energy Expenditure (EE) in the free-living environment. A 1 minute breath sample is sufficient for EE calculation. A smartphone or laptop can display the EE data. The calorific energy required by the body is vital to healthcare (e.g. to ensure adequate feeding during physical exertion), and can provide dietary guidance for the general population. The availability of accurate calorimeters is limited, particularly for in- and out-patients. The novel analyser has been trialled against respiratory chambers. On average, resting EE was calculated to within 2.4% for 9 subjects. The prototype uses an innovative NDIR sensor and an electrochemical sensor to calculate the volumes of CO2 produced and O2 consumed, with errors of 5.4% and 3.4% found respectively compared to the chambers. Further work includes investigating the energy cost of food digestion.

Australian Aboriginal freshwater shell middens from late Quaternary northwest Victoria: Prey choice, economic variability and exploitation

Abstract The Central Murray River Valley in northwest Victoria contains a rich and diverse archaeological history spanning the last 20,000 years, which has the potential to help inform on past human behaviour and subsistence strategies. In particular, freshwater shell middens are important as they can provide information about the local aquatic economy, and the role of these molluscs in the diet of Aboriginal hunter–gatherers. Many of the middens in the region consist of thin temporal horizons while being laterally expansive in size (some measuring up to 400 m in length). These middens are dominated by two aquatic molluscs: the river mussel Alathyria jacksoni and the river snail Notopala sublineata. However whilst it is generally accepted that Alathyria jacksoni was a common human prey species, it is thought that the smaller gastropod Notopala sublineata was collected accidentally as by-catch and was not economically important. To investigate, two spatially and temporally distinct middens from different land-systems spanning the late Pleistocene to the late Holocene were studied to look at the variety and size of mollusc species. To supplement the archaeological record, the potential economic and nutritional quality of the bivalve Alathyria jacksoni was investigated. The nutritional results indicate that while Alathyria are low in fat (but are good sources of omega 3- and 6-fatty acids), they are high in protein and calorific energy (kj), and are excellent sources of magnesium (Mg), Iron (Fe), Sodium (Na) and Zinc (Zn). These results coupled with the modern behavioural ecology of these freshwater molluscs, as well as ethnographic and modern cooking experiments, help identify human foraging and subsistence strategies in this region. Results indicate that despite earlier ideas, the river snail Notopala sublineata was an important economic aquatic resource during the late Pleistocene and Holocene.

Ash Content and Calorific Energy of Corn Stover Components in Eastern Canada

Corn stover is an abundant agricultural residue that could be used on the farm for heating and crop drying. Ash content and calorific energy of corn grain and six stover components were measured from standing plants during the grain maturing period, between mid-September and mid-November. Ash of stover in standing corn averaged 4.8% in a cool crop heat unit zone (2300–2500 crop heat units (CHU)) and 7.3% in a warmer zone (2900–3100 CHU). The corn cob had the lowest ash content (average of 2.2%) while leaves had the highest content (from 7.7% to 12.6%). In the fall, ash content of mowed and raked stover varied between 5.5% and 11.7%. In the following spring, ash content of stover mowed, raked and baled in May averaged 3.6%. The cob and stalk located below the first ear contained the highest calorific energy with 17.72 MJ·kg−1. Leaves and grain had the lowest energy with an average of 16.99 MJ·kg−1. The stover heat of combustion was estimated at 17.47 MJ·kg−1 in the cool zone and 17.26 MJ·kg−1 in the warm zone. Based on presented results, a partial “cob and husk” harvest system would collect less energy per unit area than total stover harvest (44 vs. 156 GJ·ha−1) and less biomass (2.51 vs. 9.13 t·dry matter (DM)·ha−1) but the fuel quality would be considerably higher with a low ash-to-energy ratio (1.45 vs. 4.27 g·MJ−1).

Iodine status of soils, grain crops, and irrigation waters in Pakistan

A study was carried out across 86 locations of the country to investigate iodine supply potential of soils, grains and underground waters for onward design of an environmental intervention in Pakistan. Wheat crops were the principal crop in this study since it supplies 75 % of calorific energy in an average Pakistani diet. TMAH-extractable iodine in soils provided a geometric mean of 0.66 µg g−1, far lower than the worldwide mean of 3.0 µg g−1 for soil iodine. Bioavailable (water-extractable) iodine concentration had a geometric mean of 2.4 % (of TMAH-extractable iodine). Median iodine concentrations in tube well sourced waters were 7.3 µg L−1. Median wheat grain-iodine concentrations were 0.01 µg g−1. In most of the grain samples, TMAH-extractable iodine was below detection limit of 0.01 µg g−1. The highest wheat grain iodine was measured on a soil having highest TMAH-extractable iodine. An iodine intake of 25.4 µg a day has been estimated based on median wheat grain iodine measured and groundwater consumption compared to world health organisation (WHO) recommendations of iodine intake of 150 µg a day. This nominal intake of iodine is alarming since 60 % of Pakistani households do not consume iodised salt.

Potencial de energía calorífica de los residuos sólidos municipales para reemplazar el carbón mineral

El aprovechamiento material y energético del residuo sólido municipal para la fabricación industrial de combustible derivado de residuos (RDF, por su sigla en inglés), constituye, por una parte, una oportunidad para la gestión ambiental empresarial; por otra parte, sirve para apoyar en las regiones la gestión integral de residuos sólidos en el sector público. Este estudio analiza el potencial calorífico del residuo sólido municipal (RSM) de la provincia de Guanentá, como base para la producción de RDF en reemplazo del carbón mineral en la industria cementera para la producción de clínker. Se concluye que con el uso de RDF, como combustible renovable sustituto, se evita el 5,72% de emisiones de gases de efecto invernadero (GEI), se generan 12.300 Ton/año de carbono neutral y se evitan 1.128 Ton/año de GEI al reemplazar, con el potencial de RSU, el 5,4% del carbón mineral requerido.

Research on Calculation Method of Alternative Fuel Quantity for Natural Gas Bus

There is no more in-depth research in the amount of alternative between natural gas and tradition fuel. The paper consider two factors about gas calorific value and vehicle level and put forward the fuel calorific value correction coefficient and vehicle energy efficiency correction coefficient. On this basis, the coefficient table and calculation method was established. The paper proved that because of the influence of the factors, equivalent ratio in the range of 1.13~1.67. The method can indicate the gas replacement more scientific and real, because of consider of the actual situation of application of the enterprise.The research can guide the selection of natural gas vehicle reasonable and scientific.

Energy production of poplar clones and their energy use efficiency

The poplar clones of Robusta and I-214 (Populus × euramericana) are characterized by fast growth and high quality biomass production. The calorific values for these poplar clones were determined, and modelling of calorific production of the entire poplar clone stands was performed. This research, dependent on age and site indexes, was conducted in four localities in Eastern Slovakia and seven in the western region of this country. Samples of bark, wood and small-wood with bark were excised from three tree stem areas and from two parts of the crown. No significant difference was observed between the two clones, with regard to either the biomass fraction or the location of the excised sample on the tree. The average calorific capacity of all biomass fractions was approximately 6.86-8.73 GJ m-3, with the lowest bark values emanating from the stem base. The mean annual calorific energy production for site indexes 40-20 after 17-26 years growth was 320-80 GJ ha-1 a-1, and this was calculable 2-3 years earlier in the I-214 clone than in Robusta. The energy use efficiency of these poplar clones was estimated at a maximum of 0.4-1.6% solar radiation utilization.