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Pyrolysis of food waste using microwave irradiation was carried out in this study to produce quality biochar for heating applications. Optimum conditions for microwave-assisted pyrolysis of food wa...

Scarce of good quality water for processing especially in the surrounding area of the mining sites dictates searching for new water resources. One of the available solutions is saline water as a flotation medium particularly in the regions close to the sea. Using the saline water, the most likely, enhances the flotation of naturally hydrophobic coal particles. Therefore, in this study, MgCl2, NaCl, and CaCl2 were tested for coal flotation and for reducing its ash content. The coal sample was characterized by size analysis as well as proximate and ultimate analyses to determine the ash content, volatile matter, moisture, and fixed carbon. Flotation experiments were conducted using salts either separately or in a mixture. The statistical design was mainly used to study the main effect of each salt as well as the interactive effects of binary and tertiary mixtures. The results showed that the MgCl2, as a single salt, is the best among the used salts in decreasing the ash percentage. On the other hand...

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 mod...

This study was carried out to develop a correlation for the prediction of calorific values of high ash lignite coals. The multiple linear regression models were developed for estimation of calorific values of high ash Pakistani lignite coals. Three models were developed based on proximate components such volatile, ash, and fixed carbon, on as-received, moist free coal datasets from Khushab, Mianwali, Jhelum, and Chakwal regions. The linear regression models were developed, and tested using analysis of variance, an absolute error estimate, and compared with earlier studies available in the literature. According to the findings, all the three models predicted the response, within acceptable limits of error. The two models developed in this study involving i) ash, volatile matter, and fixed carbon and ii) ash and fixed carbon as independent variables were recommended for the prediction of high ash lignite coals from this study.

The element contents and organic matter-element relation between Lias-aged coals exposed in four fields in Gumushane and Bayburt were investigated. In general, fixed carbon and gross calorific values of the Edire and Balkaynak coals are higher than Guvercinlik and Cerci coals. The highest ash yields were observed in the Cerci coals. The concentrations of Mg, P, Ca, Mo, Y, Ni, U, Zn, Ga, Ba, W, Sr, Ta, and Be of the analysed coals are positively correlated with ash yield, indicating an organic affinity. The Lias-aged coals located in Gumushane and Bayburt are low-rank coals.

Utility and industrial steam generators in India are designed to burn coal for generating electricity, due to coal availability and economy. Rapid increase in coal-fired power projects increased the gap in demand and supply and therefore necessitated using available coals rather than plant design coal. Studies in different capacity boilers using coals of varying properties like gross calorific value, fixed carbon, volatile, moisture and mineral matter up to 100% in gross calorific value and 200% in mineral matter more than that of designed coal has been conducted. Performances of boilers were different than predicted due to variations in the fuel characteristics.

More than 50% of the gross reserves of Giral block, Barmer district, western Rajasthan are low grade having a calorific value less than 2,150 kcal/kg; therefore, it does not possess significant market values as a combustible fuel. The clay lignite inter-burden waste has been transformed into marketable high calorie carbonaceous fuel, fit for on the site power generation, manufacture of cement, manufacture of tiles and bricks, using a wet sieving technique. This material was transformed into a value-added product of CV (+) 2,754 kcal/kg. The separation was highly successful with more than 58% recovery. The separation technique involved the inherent self-disintegration behavior of the mineral in water followed by wet sieving and separating +1 mm fraction.

The inter clay lignite waste from lignite mining in Giral block of Barmer district of Western Rajasthan has been transformed into marketable high calorific carbonaceous fuel, using a selective breakage technique. The coal can be cleaned near the mine mouth without using water; it will avoid transportation of rocks to a distance and also avoid the water pollution problem associated with the slurry ponds. The dry process will be economical as it will not utilize water and, thus, no dewatering or drying of the product will be required. Experiments were conducted with a coal sample containing 9.07% fixed carbon, 33.43% ash, 22.50% volatile matter, and marginally lower calorific value 1,869 Kcal/kg. The preliminary data indicate that by decreasing the size of coal fraction, the energy contents increasing gradually. The highest result was obtained for the size fraction (−) 2.36 to (+) 1 mm of lignite sample.

The arbuscular mycorrhizal (AM) symbiosis, which forms between plant hosts and ubiquitous soil fungi of the phylum Glomeromycota, plays a key role for the nutrient uptake of the majority of land plants, including many economically important crop species. AM fungi take up nutrients from the soil and exchange them for photosynthetically fixed carbon from the host. While our understanding of the exact mechanisms controlling carbon and nutrient exchange is still limited, we recently demonstrated that (i) carbon acts as an important trigger for fungal N uptake and transport, (ii) the fungus changes its strategy in response to an exogenous supply of carbon, and that (iii) both plants and fungi reciprocally reward resources to those partners providing more benefit. Here, we summarize recent research findings and discuss the implications of these results for fungal and plant control of resource exchange in the AM symbiosis.

The experimental determination of heating values of vegetable oils and animal fats can be determined based on simple proximate analysis data including fixed carbon, volatile matter, yield of distilled liquid, and ash contents which can be obtained relatively easily by using common laboratory equipment. The higher heating value (HHV) (MJ/kg) of the triglyceride sample as a function of the yield of distilled liquid (D, wt%) can be calculated from: According to Eq. (2), higher heating value is a function of the yield of distilled liquid of the dry and ash-free basis. Equation (2) represents the correlation obtained by means of regression analysis. The correlation coefficient is 0.9568.

In this study, the proximate analyses, such as volatile materials (VM), fixed carbon (FC), and higher heating value (HHV), were determined for 20 lignite samples from different areas of Turkey. The...

Eight bamboo species of northeast India were carbonized in a laboratory-scale fixed bed reactor at temperature ranging from 300°C to 600°C with a heating rate of 5°C/min, and their mass balance experiments of decomposition products were done at 600°C. At this temperature, the yields of charcoal, tar, gas, and condensable liquid ranged from 23.35–28.25%, 6.46–8.85%, 6.93–10.05%, and 51.98–57.96%, respectively. Fixed carbon content of the charcoal samples varied from 62.10–67.52% indicating their suitability only for domestic use or as a fuel for gasification and not for metallurgical use.

The changes in chemical, physical, and mechanical properties of fully matured coconut shell chars in relation to carbonization temperature (range: 400–950°C) and time (range: zero–3 h) have been studied. These properties were found to be more susceptible to carbonization temperature than to time. The results indicated an increase in fixed carbon content and true specific gravity of shell chars with rise of carbonization temperature and soak time. The majority of volatilization occurred up to about 800°C. The calorific value of shell char increased sharply with rise of carbonization temperature up to 600°C, and thereafter it decreased to 800°C. The porosity of shell char increased with increase of carbonization temperature up to 600°C followed by a decrease with further rise of temperature up to the range studied. Prolonged soaking at carbonization temperatures of 600, 800, and 950°C, in general, led to slight increases in the porosity and calorific values of resulting shell chars. The results showed that ...

Biomass, with its energy-rich stores of fixed carbon and volatiles, is estimated to have a worldwide bioenergy potential ranging from nearly 10% to more than 60% of primary energy consumption [1]. ...

The higher heating value (HHV) at a constant pressure measures the enthalpy change of combustion with water condensed. The HHVs of 7 species of biomass shells were correlated with their lignin, fixed carbon, and volatile material contents. There was a highly significant correlation between the HHV of the fruit shells and the lignin, fixed carbon, and volatile material contents. The HHVs (MJ/kg) of the biomass shells as a function of lignin (LC), fixed carbon (FCC), and volatile material (VMC) contents were calculated using the following equations: HHV = 0.0864 (LC) + 16.6922, (2) HHV = −0.066 (FCC)2 + 0.5866 (FCC) + 8.752, (3) HHV = −0.0066 (VMC)2 + 0.7371 (VMC) + 1.2305 (4) for Equations (2)–(4), which in square of the correlation coefficients (r2) were 0.9734, 0.8281, and 0.8281, respectively.

To investigate the relations between assimilations of photosynthetically fixed carbon (C) and newly absorbed nitrate, 13CO2 and 15NO3 − were fed to five-week-old hydroponically grown spinach (Spinacia oleracea L. cv. Lead) plants, and the assimilation of 13C and 15N into biochemical fractions was followed at the whole plant level during six hours. After 75-min pulse feeding with 13CO2 and 90-min initial feeding with 15NO3 − (designated as 0 h), the photosynthetically fixed 13C was largely found as the form of sugars in leaf blades and the newly absorbed 15N as nitrate in roots. During a further six hours of chase feeding with non-labeled CO2 and continuous 15NO3 − supply, the amounts of 13C in sugars, organic acids, undefined C and amino acids gradually decreased in leaf blades while those in C compounds (except sugars and undefined C) increased in petioles and roots. 15N in the examined N compounds increased in all three organs. At 6 h, 13C in each organ was present as sugars (12–19%), undefined...

The physiological adaptation of the phosphate uptake behaviour of the cyanobacterium Anacystis nidulans (Synechococcus leopoliensis) has been studied under phosphate-deficient conditions. We show that, during additions of pulses of phosphate, the individual cells of a population potentially develop a coherent behaviour with respect to the kinetic and energetic properties of the high-affinity phosphate uptake system. These adaptive responses are independent of the amount of stored phosphate and the absolute external phosphate concentration, but depend on the exposure time to elevated phosphate concentrations. We demonstrate that the response to additions of pulses of phosphate triggers further metabolic alterations to CO2 fixation, and the flow of fixed carbon into the pool of low-molecular weight-compounds or glycogen. These alterations may also affect subsequent growth. The ecological relevance of the adaptive phosphate uptake behaviour is discussed with respect to the establishment and stability of natu...

Evaluation of the results of a carbonization process is usually carried out by means of indicators such as mass yield, energy yield, or balanced mass yield. However, these indicators have some limits or drawbacks. A new indicator, the reference mass yield, is defined, based on the results of a well-controlled laboratory experimentation. This reference mass yield combines the mass yield and the fixed carbon content of the charcoal. It is a constant independent of the fixed carbon content, hence of the carbonization temperature. Some carbonization results from the literature are evaluated by means of the reference mass yield.

Summary Intracellular symbiosis between invertebrates and microalgae occurs in a wide range of host species and probably involves an almost equally wide range of algal species. Despite this diversity, in almost every case these associations exhibit the following properties: symbiotic algae release photosynthetically fixed carbon to their hosts; symbiotic algae utilize ammonium excreted by hosts; and growth of symbionts is closely regulated to that of hosts. Interactions between host and symbiont are discussed in terms of these common properties. It is concluded that although the origins of these symbioses are unclear, development of mechanisms constraining algal cell division were crucial in the evolution of stable, sustain-able and intimate relationships between very different species.

A technique whereby substantial portions of bituminous coals are extracted, non-destructively using N-Methyl-2-Pyrrolidone under mild conditions (202° C and 1 atm pressure) was previously reported. Herein, a parametric study on the extraction step is presented and a possible mechanism on the extraction is proposed. The extent of extraction shows little dependence on the solvent-to-coal ratio, coal particle size and treatment time whereas coal type and treatment temperature significantly affect the extent of extraction. Extractions for 26 different coals are reported and the results show reasonable correlation with the ratio of the volatile matter to fixed carbon (VM/FC), i.e. the inverse of the fuel ratio of the coal. A postulated mechanism of extraction is based on the assumption of the two-phase structure of coal. Electron Paramagnetic Resonance (EPR) studies of the raw coal, and unextracted and extracted species support the proposed mechanism and lend support to the two-phase model of coal str...

Transmetatarsal amputation (TMA) can be due to diabetes, vascular insufficiency or trauma. Ankle kinematics and kinetics is modified during walking in people with TMA (Mueller et al. 1998; Dillon e...

The primary factor causing carbonization of pollen and spores during experimental metamorphism of Waimatua lignite is temperature in excess of 200°C. A secondary factor is the length of time the pollen and spores are subjected to high temperatures. Pressure, however, retards carbonization. Both experimental and field evidence indicate that significant palynomorph carbonization occurs in samples with fixed carbon of 60–65 % and greater.