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    RAPID EX SITU COLLECTION AND THERMAL BEHAVIOR ANALYSIS OF VOLATILE ORGANIC MATTERS BY THERMAL EXTRACTION CONE CHAMBER FOR HIGH UN-BURNT CARBON COAL FLY ASH

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    A thermal extraction cone chamber system has been modified to measure differential thermal functions and products where overall volatile organic matters are lost to the environment during heating. The aims of the research are to analyze and measure the thermal behavior of high un-burnt carbon coal fly ash derived from textile industrial power in Bandung. Efforts are being made to find the solution in large-scale utilization for alternative energy based on their by product. The sample analysis show that volatile organics matter exceed 30%, which means that others oxides element content are independently favorable. The modified cone chamber can collect the sample up to the total volumes of 30% of the chamber. In contrast to traditional chamber sample collectors, the modified cone extracts volatile organics matter from high un-burnt carbon coal ash divided in two treatments. Results show that the energy of pyrolisis, direct combustion or simple carbonization can be recovered (20%-42%) from wet or dry sample, with extraction efficiency compound-specific. During the direct combustion experimentation, resulted to the embedded energy is pushing up to 2790C for the average of volatile organic matters of 34% and for pyrolisis experimentation is 3300C for average volatile organic matters of 30%. The maximum thermal productivity values of 80 minutes for the direct combustion is 10220C and for pyrolisis is 10310C, and the contrary of 10 minutes, for the direct combustion is 7430C and for pyrolisis is 7010

    The Effect of Wood Tar and Molasses Composition on Calorific Value and Compressive Strength in Bio-coke Briquetting

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    Biomass-based materials have the potential to replace conventional cokes for blast furnaces in the steel manufacturing study. Biomass as a renewable energy source can reduce the consumption of coking coal. The current challenge is saving fossil energy and waste management. The steelmaking industry with environmentally friendly processes and high energy efficiency is expected today. Many researchers have partially developed biomass as an alternative renewable resource to replace fossil fuels. This study aimed to determine the effect of composition the blending ratio of wood tar and molasses as a binder on the calorific value and compressive strength of bio-coke. The carbonization of redwood waste to produce high-quality charcoal was carried out at 500 °C with a kiln rotation speed of 20 rpm and a slope of 5°. The resulting charcoal showed a promising result with a 23.87 MJ/kg calorific value. The carbonization process of the redwood increased the fixed carbon value by up to 130% and the calorific value by 40%. The second part of this study focuses on bio-coke production by blending coking coal with redwood charcoal at 90:10 wt%. The coking coal and the redwood charcoal particle sizes were 40 and 50 mesh, respectively. A 15 wt% binder was added to increase the compressive strength of the bio-coke. The binder composition ratios of molasses: wood tar were 15:0, (12.5:2.5), and 10:5 wt%. The briquette was pressed using a cylinder die with a height: diameter ratio of 2.7:5.0 cm, then compacted up to 20 MPa followed by heating at 1100 °C for four hours. The bio-coke with a binder composition of 2.5 wt% wood tar + 12.5 wt% molasses produced a compressive strength of up to 5.57 MPa with a sulfur content of 0.8 wt% and produced a calorific value of 31.25 MJ/kg with an ash content of 9.6%. The study showed that the bio-coke produced meets some requirements for steelmaking industry

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Variations on the Author

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    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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