|
|
|
Coal Information
Accrue Minerals Inc
is the operating division within the Group that is responsible for the overall global Sourcing Supply, Trading, and Logistic services for various Bulk Minerals products that are supplied to our customers that include such items as; Coal, Iron, Chrome, Manganese, Nickel, Copper, also other Ores and Semi-Finished Products such as Copper Cathodes. As the Bulk Ore Market changes on a daily basis, the availability of Ore products can change in a matter of hours, so please forward your detailed Product Order request here. Accrue Ore Projects Inc, is the Division responsible for future ore Resource and Mining Developments, so if you have a Mine or Mineral Resource for sale or wish to purchase a Mine or future Mineral Resource please forward us your target profile for assistance here. COAL INQUIRY'S: If you have any Coal related demands or stock for sale please forward your full inquiry details to our London Office for our immediate attention here. COAL CONVERSION STATS - Link.  |
Coal Price Index's
Coal Prices such as the RBI Index on the left change on a daily basis so constant review of pricing is always advised...
For an updated Index please follow this link. Anthracite Coal InfoWhat is anthracite?
Anthracite is one of the highest rank coals, noted for its low volatile content (<10% on an air dry basis), its high fixed carbon content (>80% on an air dry basis) and its hardness (HGI is usually <40). In general, a coal is classified as 'anthracite' if it has volatile matter of less than 10% (air dry basis) although some regional definitions vary. Coals with lower fixed carbons than 80%, and volatiles of around 10-12% are most often described as "semi anthracites" and are marketable into low volatile PCI and/or power generation sectors. The largest anthracite resouces in the world are found in parts of the former USSE, China and Vietnam. However, Canada (British Columbia) and Australia (Bowen Basin) have areas of lower volatile coals which are considered to be anthracite. South Africa, also is one of several other countries that produce and market anthracite. Within a total global market estimated in excess of 110 million tonnes per annum, of which the seaborne market is comprised of some 14 M tonnes, anthracite has number of specific commercial applications including; • Graphitising material for electrode paste; • as a reductant for reducing metal oxide ores; and • as an efficient and clean fuel for heating There are a few other markets - most notably in the treatment of certain bulk chemicals such as soda ash manufacture, making calcium carbide, or certain cement making processes where anthracite has niche applications. |
Coal Basics
Coal is the world’s most plentiful fossil fuel. It is a mineral formed from the remains of land-based plants buried hundreds of millions of years ago and subjected to tremendous heat and pressure. -
The rank of coal is based on the degree to which the original plant material has been transformed into carbon and can be seen as a rough indication of how old the coal is: the older the coal the higher the carbon content (generally).
The ranks of coal (from most to least carbon content) are as follows: anthracite, bituminous coal, sub-bituminous coal, and lignite.
The coal with the highest carbon content is the best and cleanest type of coal to use. As you move down the coal rank the heat given out decreases and the dirtiness of the fuel and moisture content increases.
Types of Coal and Uses:
Coal is used mainly for two purposes, for steel-making and power generation. Coal is classified according to the degree of transformation of the original plant material into carbon, moisture content and composition. Coal is normally classified under the following four main categories: [worst to best]
Coal is the world’s most plentiful fossil fuel. It is a mineral formed from the remains of land-based plants buried hundreds of millions of years ago and subjected to tremendous heat and pressure. -
The rank of coal is based on the degree to which the original plant material has been transformed into carbon and can be seen as a rough indication of how old the coal is: the older the coal the higher the carbon content (generally).
The ranks of coal (from most to least carbon content) are as follows: anthracite, bituminous coal, sub-bituminous coal, and lignite.
The coal with the highest carbon content is the best and cleanest type of coal to use. As you move down the coal rank the heat given out decreases and the dirtiness of the fuel and moisture content increases.
Types of Coal and Uses:
Coal is used mainly for two purposes, for steel-making and power generation. Coal is classified according to the degree of transformation of the original plant material into carbon, moisture content and composition. Coal is normally classified under the following four main categories: [worst to best]
- Lignite: also referred to as brown coal, is the lowest rank of coal and used almost exclusively as fuel for electricity power generation. - Lignite has a calorific value of less than 5 kw/kg approximately. - Lignite is brownish black, has a high moisture content (up to 45 %), and a high suphur content.
- Sub-bituminous coal: whose properties range from those of lignite to those of bituminous coal is used primarily as fuel for electricity power generation. This coal generally has a lower sulfur content than other types, which makes it attractive for use because it is cleaner burning. - Sub-bituminous coal has calorific values ranging from 5 - 6.8 kW/kG approximately. -Sub-bituminous coal black and contains 20-30 % moisture.
- Bituminous coal: is black and sometimes dark brown, often with well-defined bands of bright and dull material. It is used primarily as fuel in electricity power generation, with substantial quantities also used for heat and power applications in manufacturing and to make coke for steel making. - Bituminous coal has calorific values ranging from 6.8 - 9 kW/kG approximately. - a moisture content less than 20 %.
- Anthracite coal: is a hard, glossy black coal that is used for home heating and steel making. - Anthracite has a calorific values of around 9 kW/kG or above. - moisture content generally is less than 15 %.
The C02 production cycle:
As you can see the picture left illustrates that sustainability sourced wood fuel has a relatively low effect on CO2 level in the atmosphere.
This is because for every tree that is burnt another takes it's place and by simply growing absorbs the CO2 that was released by burning the first tree - simple.
Obviously some CO2 is produced as a result of the processing and transport of the fuel.
If timber is of building quality, and would be used for building with otherwise, then it is better to use this wood for building with and other parts of the tree for burning.
Timber production is a little limited in the UK for a variety of reasons some historical, some to do with our climate, and in fact wood-fuel production and building timber production often go hand in hand.
As you can see the picture left illustrates that sustainability sourced wood fuel has a relatively low effect on CO2 level in the atmosphere.
This is because for every tree that is burnt another takes it's place and by simply growing absorbs the CO2 that was released by burning the first tree - simple.
Obviously some CO2 is produced as a result of the processing and transport of the fuel.
If timber is of building quality, and would be used for building with otherwise, then it is better to use this wood for building with and other parts of the tree for burning.
Timber production is a little limited in the UK for a variety of reasons some historical, some to do with our climate, and in fact wood-fuel production and building timber production often go hand in hand.
COAL GLOSSARY
ADB - Air-Dried Basis.
In coal sample analysis, ADB neglects the presence of moistures other than inherent moisture while DB (dry-basis) leaves out all moistures, including surface moisture, inherent moisture, and other moistures.
ARB - As-Received Basis.
In coal sample analysis, ARB puts all variables into consideration and uses the total weight as the basis of measurement. ARB is the most widely used basis in industrial applications.
Ash Content –
Ash content is the non-combustible residue that remains after coal is burnt. Ash reduces handling and burning capacity, affects combustion efficiency and boiler efficiency and therefore increases handling costs.
ASTM - American Society for Testing and Materials.
GAR & NAR -
Thermal coal is quoted on a GAR (Gross as Received) basis...... Except for Europe/ARA, Richards Bay 6,000 kcal/kg, and Japan and Korea West CIF, which are all quoted on a NAR (Net As Received) basis.
Fixed Carbon –
Fixed carbon is the solid combustible residue that remains in the furnace after volatile matter is distilled off, comprised mostly of carbon but also containing some hydrogen, oxygen, sulphur and nitrogen not driven off with the gases. It provides a rough estimate of the heating value of coal.
HGI –
The relative ease with which coal can be pulverised depends on the strength of the coal and is measured by the Hardgrove Grindability Index (HGI). This empirical test indicates how difficult it would be to grind a specific coal to the particle size necessary for effective combustion in a pulverized coal fired boiler
Inherent Moisture –
Inherent moisture (or bed moisture) means moisture that exists as an integral part of the coal seam in its natural state, including water in pores, but excluding that present in macroscopically visible fractures.
Sulphur –
Sulphur content in coal presents problems with utilization and resultant pollution, as it causes corrosion and fouling of boiler tubes, and atmospheric pollution when released in flue gases.
Total Moisture –
Total moisture in coal is represented by measuring weight loss from aggressive drying in an air atmosphere under rigidly controlled conditions of temperature, time and air flow. The presence of moisture is an important factor in both the storage and the utilization of coal, as it adds unnecessary weight during transportation, reduces the calorific value, and poses some handling problems.
Volatile matter –
Volatile matter is the material that is driven off when coal is heated to 950 °C in the absence of air under specified conditions. It consists of a mixture of gases, low-boiling-point organic compounds that condense into oils upon cooling, and tars. In general, coals with high volatile-matter content ignite easily and are highly reactive in combustion applications.
ADB - Air-Dried Basis.
In coal sample analysis, ADB neglects the presence of moistures other than inherent moisture while DB (dry-basis) leaves out all moistures, including surface moisture, inherent moisture, and other moistures.
ARB - As-Received Basis.
In coal sample analysis, ARB puts all variables into consideration and uses the total weight as the basis of measurement. ARB is the most widely used basis in industrial applications.
Ash Content –
Ash content is the non-combustible residue that remains after coal is burnt. Ash reduces handling and burning capacity, affects combustion efficiency and boiler efficiency and therefore increases handling costs.
ASTM - American Society for Testing and Materials.
GAR & NAR -
Thermal coal is quoted on a GAR (Gross as Received) basis...... Except for Europe/ARA, Richards Bay 6,000 kcal/kg, and Japan and Korea West CIF, which are all quoted on a NAR (Net As Received) basis.
Fixed Carbon –
Fixed carbon is the solid combustible residue that remains in the furnace after volatile matter is distilled off, comprised mostly of carbon but also containing some hydrogen, oxygen, sulphur and nitrogen not driven off with the gases. It provides a rough estimate of the heating value of coal.
HGI –
The relative ease with which coal can be pulverised depends on the strength of the coal and is measured by the Hardgrove Grindability Index (HGI). This empirical test indicates how difficult it would be to grind a specific coal to the particle size necessary for effective combustion in a pulverized coal fired boiler
Inherent Moisture –
Inherent moisture (or bed moisture) means moisture that exists as an integral part of the coal seam in its natural state, including water in pores, but excluding that present in macroscopically visible fractures.
Sulphur –
Sulphur content in coal presents problems with utilization and resultant pollution, as it causes corrosion and fouling of boiler tubes, and atmospheric pollution when released in flue gases.
Total Moisture –
Total moisture in coal is represented by measuring weight loss from aggressive drying in an air atmosphere under rigidly controlled conditions of temperature, time and air flow. The presence of moisture is an important factor in both the storage and the utilization of coal, as it adds unnecessary weight during transportation, reduces the calorific value, and poses some handling problems.
Volatile matter –
Volatile matter is the material that is driven off when coal is heated to 950 °C in the absence of air under specified conditions. It consists of a mixture of gases, low-boiling-point organic compounds that condense into oils upon cooling, and tars. In general, coals with high volatile-matter content ignite easily and are highly reactive in combustion applications.