Gasification Daily Question: 12/4/2016 – Process analysis question (5 points for participation, 10 points for a correct answer)
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This post was last edited by tfx511024 on 2016-12-5 at 21:06. Daily Vaporization Question: Process analysis question for 2016-12-4 (5 points for participation, 10 points for a correct answer). What are the common industrial analysis benchmarks for coal quality? Answer: Five common benchmarks: (1) receipt basis. Based on the coal in received condition, it is referred to as the received basis, denoted by ar. (2) Air-dry basis. Coal that has reached an air-dry state is used as the basis, referred to as the air-dry basis, denoted by ad. (3) Dry basis. Based on the hypothetical anhydrous state of coal, it is referred to as the dry basis, denoted by d. (4) Dry ash-free base. Based on the hypothetical coal in an anhydrous and ash-free state, it is referred to as the dry ash-free basis, denoted by DAF. (5) Dry, mineral-free base. The search is based on coal in an hypothetical anhydrous and mineral-free state, referred to as the dry mineral-free basis, denoted by dmmf.
On a basis of received material, air-dried basis, dried basis, dried ash-free basis
The commonly used bases for industrial coal analysis are as received, air-dried basis, dry basis, and dry ash-free basis.
On a basis of received material, on an air-dried basis, on a dried basis, on a dried ash-free basis
(1) Received base. Based on the coal in received condition, it is referred to as the received basis, denoted by ar. (2) Air-dry basis. Coal that has reached an air-dry state is used as the basis, referred to as the air-dry basis, denoted by ad. (3) Dry basis. Based on the hypothetical anhydrous state of coal, it is referred to as the dry basis, denoted by d. (4) Dry ash-free base. Based on the hypothetical coal in an anhydrous and ash-free state, it is referred to as the dry ash-free basis, denoted by DAF. (5) Dry, mineral-free base. Using coal in an imaginary anhydrous and mineral-free state as a reference is referred to as the dry mineral-free basis, denoted by dmmf.
On a basis of ash (ar), air-dried basis (ad), dried basis (d), dried ash-free basis (daf)
(1) Base on received value (2) Air-dried base (3) Dried base (4) Dried ash-free base (5) Dried mineral-free base
On a basis of received material, air-dried basis, dried basis, dried ash-free basis
Including air-dried basis, dried basis, received basis, dried ash-free basis, anhydrous and mineral-free basis, constant-humidity ash-free basis, etc
Parameters such as moisture, internal moisture, total moisture, moisture in the analyzed coal sample, ash, volatile matter, fixed carbon, total sulfur and various forms of sulfur, as well as calorific value. The carbon dioxide content in carbonates also falls within the scope of industrial analysis, as it is used to correct values such as volatile matter, calorific value, and elemental composition including carbon content. Generally, the moisture, ash, volatile matter, and fixed carbon of coal are referred to as the semi-industrial analysis of coal; analysis parameters such as sulfur content and calorific value are also included
Analysis bases: on a received basis, on an air-dried basis, on a dried basis, on a dried ash-free basis. 1. Received basis: It represents the percentage of various components in coal based on the coal in its received state. Denoted by the subscript ar, it takes into account the ash and total moisture content of the coal. Its composition can be expressed by the following equilibrium equation: Industrial analysis: Mar + Aar + Var + FCar = 100%, where M, A, V, and FCar represent the percentages of moisture, ash, volatile matter, and fixed carbon in the coal, respectively. 2. Air-dried basis: Due to the large variations in the external moisture content of coal, it is commonly dried naturally during analysis to remove this external moisture. The composition determined based on this state is referred to as the air-dried basis, denoted by the subscript ad. Its composition can be expressed by the following equilibrium equation: Industrial analysis: Mad + Aad + Vad + FCad = 100%. 3. On a dry basis, the various components of coal are expressed relative to coal in its anhydrous state, with the subscript d used to indicate this. Its composition can be expressed by the following equilibrium equation: Industrial analysis: Ad+Vd+FCd=100%. 4. Dry ash-free basis – The composition of coal after removal of ash and moisture; this is an imaginary state free of water and ash, and the composition based on this is denoted by the subscript daf. Its composition can be expressed by the following equilibrium equation: Industrial analysis: Vdaf + FCdaf = 100%