Users who purchase charcoal machine equipment want to earn money by selling the charcoal produced with the equipment. However, if the charcoal produced does not meet standards, it cannot be sold on the market. Suote Hongfa charcoal experts teach you how to distinguish charcoal quality. Charcoal of different quality can be defined from the following aspects:

1. Carbon Content

The carbon content of charcoal varies with the type of raw material and carbonization temperature. Generally speaking, compared with low-density woods such as poplar and paulownia, hard miscellaneous wood has a higher carbon content under the same carbonization temperature. For the same raw material, high-temperature carbonization yields higher carbon content than low-temperature carbonization. Typically, charcoal has a carbon content of less than 75%. Taking pine wood as an example, when the carbonization temperature reaches 380°C, its carbon content is 76%; when the temperature reaches 500°C, the carbon content reaches 85%; and when the temperature reaches 600~700°C, the carbon content reaches 92%.

2. Moisture Content

Since charcoal is a highly absorbent substance, it will absorb moisture from the air, thereby increasing its own moisture content. Therefore, the moisture content of charcoal does not significantly affect its quality; it is simply that customers prefer charcoal with the lowest possible moisture content to improve its economic value. Generally speaking, freshly discharged charcoal has a moisture content of less than 3%.

3. Ash Content

Ash is the white or pinkish substance that remains after charcoal has completely burned, which is commonly referred to as ash. Its amount directly affects the use and economic value of charcoal. For example, substances such as straw and rice husk have high ash content that does not easily detach during combustion, resulting in low combustion temperatures, making such charcoal unsuitable for domestic and industrial use. The ash content of charcoal varies with different carbonization processes and temperatures. However, for wood or its offcuts, the differences in ash content after carbonization are not significant. Generally speaking, under the same conditions, charcoal made from broadleaf forest wood has higher ash content than that from coniferous forest wood, and raw materials with a higher bark proportion also produce charcoal with higher ash content. Typical charcoal ash content is 1~4%.

4. Volatile Matter Content

The volatile matter content depends on the carbonization temperature. Depending on different uses, we can produce low/medium-temperature charcoal or high-temperature charcoal. The former releases volatiles such as CO, CO2, H2, CH4, and gaseous carbohydrates during high-temperature calcination, with a content generally ranging from 12% to 20%. High-temperature charcoal releases fewer of the above volatiles, with a content generally below 5%.

5. Calorific Value

The energy released per kilogram of charcoal under specific conditions, expressed in calories. The calorific value of charcoal is directly related to the carbonization temperature and holding time. Under the same carbonization temperature and holding time conditions, the calorific value of charcoal varies with different raw materials. Generally speaking, the higher the carbonization temperature and the longer the holding time, the greater the carbon content, and naturally the higher the calorific value. When the carbonization temperature is below 450°C, the calorific value of charcoal made from wood and its offcuts is typically between 6,500 and 7,000 kilocalories per kilogram, while the calorific value of straw and rice husk charcoal is generally around 6,000 kilocalories per kilogram. When the carbonization temperature exceeds 600°C, the calorific value of charcoal made from the above materials can increase by 500~1,000 kilocalories.