The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Steam plays a vital role in the gasification process. This study aims to investigate the changes in char structure and reactivity during the gasification of Victorian brown coal. A Loy Yang brown coal sample was gasified at 800°C in a novel fluidised-bed/fixed-bed reactor in three different gasification atmospheres: 15% H 2 O balanced with argon, 4000ppm O 2 balanced with CO 2...
It is known that Victorian brown coal has higher reactivity for gasification because of catalysis of inherent AAEM species than high-rank coal. However, the experimental results of steam gasification of brown coal in a fluidised-bed/fixed-bed reactor at 800°C have suggested that the inhibitory effects of the volatile–char interactions on char gasification are not negligible. The mechanisms and kinetics...
Experimental investigation of the combustion of an air-dried Victorian brown coal in O 2 /N 2 and O 2 /CO 2 mixtures was conducted in a lab-scale drop-tube furnace (DTF). In situ diagnostics of coal burning transient phenomena were carried out with the use of high-speed camera and two-colour pyrometer for photographic observation and particle temperature measurement,...
The brown coal in the Latrobe Valley, Victoria, Australia, has many unique structural features and properties. The brown coal has a very low ash yield and contains highly dispersed alkali and alkaline earth metallic (AAEM) species, either as carboxylates forming part of its organic matter or as NaCl dissolved in its moisture. Owing to its unique structural features and properties, the brown coal behaves...
The purpose of this study is to investigate the major factors influencing the Na-catalysed and non-catalysed gasification reactivity of a Victorian brown coal in steam. An acid-washed (H-form) sample and a Na-exchanged (Na-form) sample prepared from the same Loy Yang brown coal were gasified in 15% steam in a novel two-stage fluidised-bed/fixed-bed reactor. All C-containing species in the gasification...
A wire-mesh reactor capable of multi-step heating/holding and minimising secondary reactions of volatiles was used to investigate the effects of thermal pretreatment in inert gas on the subsequent rapid pyrolysis behaviour of Loy Yang brown coal. Our results indicate that the presence of small amounts (<10wt%) of moisture in brown coal has little influence on the tar and char yields from the pyrolysis...
In a fluidised-bed gasifier, char particles are in constant contact with the volatiles and the products from the gasification and thermal cracking of volatiles. The highly reactive nature of volatiles as well as the vulnerable structure of char from brown coal means that there are strong interactions between volatiles and char. The purpose of this study is to investigate the effects of volatile–char...
The purpose of this study is to further investigate the effects of volatile-char interactions on the volatilisation and dispersion of alkali and alkaline metallic species and changes in char structure during pyrolysis. Ion-exchanged (H-form, Na-form and Ca-form) Loy Yang brown coal samples were pyrolysed in a novel two-stage fluidised-bed/fixed-bed reactor over a wide temperature range of 500-930...
An attempt was made for obtaining UV/VIS absorption and fluorescence spectra of a whole Victorian brown coal and then examining the presence of aromatic ring systems (ARSs) with poly-condensed rings in the coal. Loy Yang brown coal was subjected to an alkali-promoted depolymerization in an aqueous solution of sodium hydroxide at 473 K and then dissolved nearly completely into the solution. The solution...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.