What are the typical lignites in Inner Mongolia?

The Shilinhot Shengli coal field is located in the northwest of Shilinhot city. The raw coal produced there is lignite from the Late Jurassic-Cretaceous period, with geological reserves amounting to 22.4 billion tons. The analysis results for this lignite are as follows:

**Testing parameters | Unit | Value**
Total moisture | Mt:% | 34.1
Maximum inherent moisture | MHC:% |
Industrial analysis | % |
Moisture on air-dried basis | Mad: | 19.56
Ash on received basis | Aar: | 11.22
Ash on dry basis | Ad: | 17.03
Volatiles on dry basis | Vd: | 36.07
Volatiles on ash-free, dry basis | Vdaf: | 43.47
Fixed carbon on dry basis | FCd: | 46.93
Total sulfur | St,d: | 1.52
Sulfur in pyrite form | Sp,d: |
Sulfur in sulfate form | Ss,d: |
Organic sulfur | So,d: |
Calorific value | MJ/kg |
Lower calorific value on dry basis | Qgr,d: | 21.8
Lower calorific value on ash-free, dry basis | Qgr,daf: | 26.3
Lower calorific value on air-dried basis | Qnet,ad: | 17.9
Lower calorific value on received basis | Qnet,ar: | 14.4

**Elemental analysis | %**
Carbon content | Car | 39.71
Hydrogen content | Har | 2.59 | Hd: | 3.93 | Hdaf: | 4.74
Nitrogen content | Nar | 0.62 | Nd: | 0.94 | Ndaf: | 1.13
Sulfur content | St,ar: | 1 | St,d: | 1.52 | Sdaf: |
Oxygen content | Oar: | 10.79 | Od: | 16.37 | Odaf: |

**Milling properties** | HGI: | 50

**Coal ash fusion properties** | DT °C: | 1166 | ST °C: | 1214 | HT °C: | 1250 | FT °C: | 1287

**Ash composition** | Ash | SiO2 wt%: | 52.86 | Al2O3 wt%: | 20.16 | Fe2O3 wt%: | 7.74 | CaO wt%: | 4.89 | MgO wt%: | 2.13 | SO3 wt%: | 4.5 | TiO2 wt%: | 0.99 | P2O5 wt%: | 0.41 | Na2O wt%: | 2.53 | K2O wt%: | 1.59

Ash fusion temperature: DT ℃ 1166, ST ℃ 1214, HT ℃ 1250, FT ℃ 1287. Ash composition: Ash SiO2 weight% 52.86, Al2O3 weight% 20.16, Fe2O3 weight% 7.74, CaO weight% 4.89, MgO weight% 2.13, SO3 weight% 4.5, TiO2 weight% 0.99, P2O5 weight% 0.41, Na2O weight% 2.53, K2O weight% 1.59. The acid-base ratio is relatively high; why is then the ash fusion point low? Was it me who made a mistake? Please give me some advice

Reply 2# huchsh: What’s the activation energy?

It seems you have obtained some theory from somewhere, but coal is very complex; it’s best to conduct analyses

Where does the activation energy come from? Reactivity?

Reply to 5# rhinocao: It can’t really be called a theory yet, haha. I’m planning to conduct research in this area, so I can only say that I have a slight understanding of it. If there are any mistakes, please feel free to point them out; let’s learn together and improve together. As you said, coal is a complex substance, and its ash fusion behavior is influenced by many factors such as the atmosphere, the minerals present in the ash, and the composition of the ash. There is no instrument that can determine the changes in the mineral structure of coal ash during the melting process or the complex reactions that occur. At present, no theory can adequately explain the mechanism of coal ash melting; only empirical formulas can be derived through experiments to make some predictions.

Reply to 4# Lao Wu: I also want to ask, what do you mean by activation energy?

Reply 6# rhinocao The energy required for a molecule to change from its normal state to an active state in which it is prone to chemical reactions is called activation energy. The rate of a chemical reaction is closely related to the magnitude of its activation energy; the lower the activation energy, the faster the reaction rate. Therefore, reducing the activation energy effectively accelerates the reaction. For coal types with a relatively high activation energy, increasing the gasification temperature can more significantly boost their gasification reaction rate. Shenmu coal – the activation energy is 11.8 KJ/mol; the reaction rate constant K at 1250°C is 0.57077, while it is 0.62064 at 1350°C. Baigou coal – the activation energy is 110.4 KJ/mol; the reaction rate constant K at 1250°C is 0.12478, while it is 0.27416 at 1350°C. The high activation energy of Baigou coal results in the reaction rate doubling when the temperature is increased, whereas the increase in the reaction rate for Shenmu coal is much smaller.

Thank you for the explanation from floor 9. I noticed this issue while reading today as well. The question raised by the brother earlier about what the activation energy is actually relates to the reactivity of coal; it is generally evaluated by considering the interaction of coal with certain media such as carbon dioxide and water vapor, which is similar to the method used to assess the reactivity of coke