Physical Address
304 North Cardinal St.
Dorchester Center, MA 02124
D5373-21 – Standard Test Method Technical Guide
🔬 Scope and Applicable Ranges
This standard, D5373-21, provides test methods for determining carbon, hydrogen, and nitrogen in analysis samples of coal and carbon in analysis samples of coke. Test Method A is used for carbon in the range of 54.9% to 84.7%, hydrogen from 3.26% to 5.08%, and nitrogen from 0.57% to 1.76% in coal, and carbon in coke from 86.6% to 97.9%. Test Method B covers carbon in coal (57.7% to 84.0%) and carbon in coke (86.3% to 95.4%). All percentages are mass fractions unless otherwise noted.
| 🟦 Method | 📏 Element | 🎯 Range (%) |
|---|---|---|
| Method A (Coal) | Carbon | 54.9 – 84.7 |
| Method A (Coal) | Hydrogen | 3.26 – 5.08 |
| Method A (Coal) | Nitrogen | 0.57 – 1.76 |
| Method A (Coke) | Carbon | 86.6 – 97.9 |
| Method B (Coal) | Carbon | 57.7 – 84.0 |
| Method B (Coke) | Carbon | 86.3 – 95.4 |
⚙️ Test Procedure and Conditions
In Method A, the determination involves combustion of the sample in a furnace operating at elevated temperatures. For coal, the temperature range is 900°C to 1050°C, ensuring conversion of carbon, hydrogen, and nitrogen to CO₂, H₂O, and NOₓ gases. For coke, the temperature range is 950°C to 1150°C. Method B provides an alternative procedure for carbon determination, with similar combustion principles. The standard emphasizes adherence to referenced practices for sample preparation, such as D2013 for coal and D346/D346M for coke.
| 🔧 Material | 🔥 Temperature Range (°C) |
|---|---|
| Coal (Method A) | 900 – 1050 |
| Coke (Method A) | 950 – 1150 |
📊 Key Measured Properties and Precision
The precision statements for these test methods are derived from interlaboratory studies using coals ranging from ASTM rank lignite A to low volatile bituminous, and various cokes including metallurgical and petroleum cokes. For Method A, the study included five metallurgical and seven petroleum cokes, while Method B included five each. All test results are reported in SI units, and the standard references ISO 5725-6 for accuracy practices.
Technical Note: The interlaboratory studies for precision covered a range of coal ranks and coke types. Refer to Annex A4 and A5 of the standard for detailed composition information and precision data.
❓ Frequently Asked Questions
🔍 What is the difference between Test Method A and B?
Test Method A determines carbon, hydrogen, and nitrogen in coal and carbon in coke in a single procedure, while Test Method B is specific for carbon determination in coal and coke. Method A uses temperature ranges of 900°C–1050°C for coal and 950°C–1150°C for coke, whereas Method B follows similar principles but with different validation data.
💡 What are the concentration ranges for the elements?
For Method A in coal: carbon 54.9%–84.7%, hydrogen 3.26%–5.08%, nitrogen 0.57%–1.76%. For coke in Method A: carbon 86.6%–97.9%. Method B covers carbon in coal (57.7%–84.0%) and coke (86.3%–95.4%).
⚡ Why are specific temperature ranges used?
The temperature ranges ensure complete combustion and quantitative conversion of elements to CO₂, H₂O, and NOₓ gases. Coal requires 900°C–1050°C due to its composition, while coke requires higher temperatures (950°C–1150°C) for complete combustion.
📌 What are the key referenced standards?
Important references include D121 (Terminology), D2013 (Coal Sample Preparation), D3173 (Moisture), D3176 (Ultimate Analysis), D3180 (Basis Calculations), and D5865 (Calorific Value). These support consistent testing and reporting.