Overview
SIST ISO 2950:1998 provides an internationally recognized system for the classification of brown coals and lignites. This standard, developed by the International Organization for Standardization (ISO), outlines a method to categorize these types of solid mineral fuels based on two key measurable properties: total moisture content (ash-free basis) and tar yield (dry, ash-free basis). The standard offers a concise and structured approach, using class numbers, group numbers, and code numbers to ensure consistency and clarity in the classification of brown coals across different regions and industries.
Key Topics
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Total Moisture Content (Ash-Free Basis):
- Brown coals are first divided based on their total moisture content, which is established on an ash-free basis. This parameter helps distinguish between different classes of coal.
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Tar Yield (Dry, Ash-Free Basis):
- Each class is further subdivided according to tar yield, calculated on a dry, ash-free basis. Tar yield is a crucial indicator in industrial processing and utilization.
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Classification System:
- The standard uses a two-digit code to express coal type:
- The first digit identifies the moisture class.
- The second digit specifies the tar-yield group.
- This system creates a clear taxonomy for brown coal types, aiding in standardized reporting and trade.
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Methodological References:
- The standard references analytical methods for determining total moisture (ISO/R 1015), tar yield (ISO/R 647), and ash content (ISO/R 1171).
Applications
The classification system detailed in SIST ISO 2950:1998 offers substantial practical value in several sectors:
Related Standards
For effective classification and analysis, SIST ISO 2950:1998 is commonly used in conjunction with other key international standards, including:
- ISO/R 647: Determination of tar, water, gas, and coke yields by low temperature distillation of brown coal and lignite.
- ISO/R 1015: Determination of moisture in brown coals and lignites by the direct volumetric method.
- ISO/R 1171: Determination of ash content in solid mineral fuels.
These related standards define the methods for measuring the core properties needed for the classification defined in SIST ISO 2950:1998.
Keywords: brown coal classification, lignite types, total moisture content, tar yield, coal quality standards, international coal standards, ISO 2950, SIST standards, coal trade compliance, coal analysis methods