Anthracite coal, mined from the planet's oldest geological formations, has spent the longest time underground. The coal has been subjected to the most pressure and heat, making it the most compressed and hardest coal available. Hard coal contains greater potential to produce heat energy than softer, geologically "newer" coal.
Mar 28, 2018· Ash fusion temperatures are determined by viewing a molded specimen of the coal ash through an observation window in a high-temperature furnace. The ash, in the form of a cone, pyramid or cube, is heated steadily past 1000 °C to as high a temperat...
5.1 The design of most coal combustion and coal conversion equipment anticipates that the ash either remain solid or assume some degree of fluidity, depending on the particular design. Ash fusibility temperatures help predict whether the ash will perform properly in the process for which the coal .
Coal sampling and analysis standards 8 4.4.1 Preparation of coal ash 58 4.4.2 Major and minor elements 59 4.4.3 Trace elements 61 4.5 Miscellaneous analysis 64 4.5.1 Chlorine 64 4.5.2 Mercury 65 4.5.3 Mineral matter in coal 66 4.5.4 Ash fusibility 66 4.5.5 Coal
Fuels with lower ash fusion temperatures require more precise combustion tuning and increased sootblowing to mitigate slag deposits. Let's take a look at the coal ash fusion D1857 analysis shown ...
Coal Specifications. We exclusively trade thermal coal of Indonesian origin and offer three main calorific values – GAR 4200 kcal/kg, NAR 4700 kcal/kg and NAR 5500 kcal/kg. The table below indicates the typical specifications of each category of coal under the .
ash of high melting-points would not increase the ash fusion temperatures above a certain blending ratio. The significant variation in the chemistry and mineralogy of the ash as a result of coal blending and mineralogical interactions was the main reason for the changes to the ash sintering and fusion .
Apr 08, 2011· Re: Ash fusion temperature. Dear Mr.Ted, As per my understanding the higher the ash fusion temperatures better will be its performance in terms of fouling and slagging in power plant boiler tubes. High alkali containing fly ashes generally do have low ash fusion temperatures.Indonesian coal which is largely used in power plants.
The extent of coal ash slag penetration and refractory brick dissolution depends on the slag viscosity, the gasification temperature, and the composition of slag and bricks. We measured the viscosity of several synthetic coal ash slags with a high-temperature rotary viscometer and their ash fusion temperatures through optical image analysis.
CORRELATING THE SLAGGING OF A UTILITY BOILER WITH COAL CHARACTERISTICS Rod Hatt Coal Combustion, Inc. Versailles, KY 859-873-0188 ABSTRACT This paper will describe how a utility was able to correlate intermittent slagging problems a boiler was experiencing with coal ash chemistry. The coal ash fusion temperatures alone were not sufficient to be
Aug 17, 2017· There are several coal boilers and gasifiers that operate with a flame temperature over the melting or fluid properties of the coal ash, commonly called ash fusion temperature, AFT.
Specific ash-fusion temperatures are determined in the laboratory by observing the temperatures at which successive characteristic stages of fusion occur in a specimen of ash when heated in a furnace under specified conditions. These temperatures are often used as indicators of the clinkering potential of coals during high-temperature processing.
Bituminous coal can be categorized further by the level of volatile matter; it contains high-volatile A, B, and C, medium-volatile, and low-volatile. Volatile matter includes any material that is liberated from the coal at high temperatures. In the case of coal, the volatile matter may include sulfur and hydrocarbons.
Ash fusion, also called fusibility, is a test to determine how the ash residue remaining from combustion of a coal will react in a furnace or boiler. In this test, coal ash is put into conical molds as specified in ASTM method D1857-04 guidelines and procedures (American Society .
Ash Fusion Temperature Ash fusion temperatures give an indication of the softening and melting behavior of fuel ash. These temperatures are widely cited in fuel specifications for boilers despite a relatively poor record of correlating with slogging or fouling behavior.
The coal ash fusion at a low temperature, encourages the formation of a clinker that gathers around the heat transfer pipes and thereby corrodes the furnace components. It is well-known that the ash clinkering may lead to channel burning, pressure drop, and an unstable gasifier operation (Van Dyk et al.
Ash Fusion Temperature ARCH CEN T THE CONCEPT The Energy Research Company (ERCo) and the Lehigh University Energy Research Center (ERC) team have developed a system for on-line, in-situ, real-time measurement of coal properties. The system includes artificial intelligence (AI) models to accurately predict the slagging propensity of coal and ...
Ash Fusibility. Fusion temperatures provide an indication of the temperature range over which portions of the ash will be a molten fluid or semi-molten, plastic state. High fusion temperatures indicate that ash released in the furnace will cool quickly to a nonsticky state resulting minimal potential for slagging.
Sep 09, 2014· In the present investigation, few Indonesian coal samples have been selected to find out the direct effect of ash chemical composition and ash fusion temperatures. Experimental: The composition of several coal ashes were determine by ASTM D6349-09 method using Perkin Elmers Optima 700 DV, ICP-OES. The sample digestion was carried out in a ...
• Fusion characteristics of Ash is estimated from the Initial Deformation Temperature, Hemispherical Temperature and Fusion Temperature of the ash • Ash oxide analysis is commonly used for analysis of ash composition. • Ash analysis is used to characterize the slagging and fouling potential of coal .
If the ash fusion temperature is low say 1000 degree celsius it may be helpful for binding of coal and coke. Higher ash fusion temperature also should help in binding whish is arequirement for ...
Bruce G. Miller, in Clean Coal Engineering Technology, 2011. Ash Fusion. The ash fusion temperature is a measure of when the ash will melt and transform from a solid to liquid state. This temperature is an important parameter for the design and operation of gasification systems, for those that operate below the ash fusion temperature so as not to incur fusion, sintering, or clinkering of the ...
Other properties. Low ash-fusion temperature: The mineral fraction of the Blue Gem is dominated by siderite, rather than silicates. This gives the coal a low ash-fusion temperature that is favorable in the production of silicon metal (Gardner and others, 2007; Hower and others, 2007).
A mechanistic study is detailed in which coal ash is heated with its shrinkage measured continuously up to a temperature of 1600°C. The temperatures corresponding to the rapid rate of shrinkage correspond to the formation of eutectics identified on phase diagrams.