Investigation on coal types used for water-coal slurry gasification

Personal opinion: 1. Suitable coal types for pressurized gasification of coal slurry – Anthracite is not suitable for this process due to its low reactivity, low carbon conversion rate, and low grindability index. ·Lignite has a high content of internal moisture, large internal pore surfaces, and strong water absorption capacity; as a result, a large amount of water can be adsorbed onto the coal particles during slurry formation. Therefore, under the same concentration of coal slurry, the amount of water available for free flow is reduced, leading to poor fluidity. To achieve the same level of fluidity, the concentration of the coal slurry must be decreased. Hence, lignite has poor slurry-forming properties, and it is not suitable as a raw material for pressurized gasification using coal slurry at present. ·Bituminous coal is suitable for pressurized gasification of coal slurry, and among bituminous coals, long-flame coal and gas coal are the most appropriate. Therefore, pressurized gasification of coal slurry has certain requirements regarding the quality of bituminous coal: even long-flame coal and gas coal, if their ash fusion temperature is greater than 1400°C and the viscosity of their ash is high, are not suitable as coal for the Texaco gasification process. 2. Coal usage by some domestic coal chemical enterprises that employ the water-coal slurry gasification process · Shandong Lunan Fertilizer Factory uses Beisu and Luoling bituminous coals from Chongzhou Coal Mine. ·Shanghai Coking uses Shandong Beisu bituminous coal and Shaanxi Shenfu bituminous coal. ·The Weihe Fertilizer Factory uses bituminous coal from Huating, Gansu. ·The Yankuang Guotai plant uses a multi-nozzle opposed water-coal slurry gasifier with a daily processing capacity of 1,000 tons of coal; it employs mixed bituminous coal, that is, bituminous coal from Beisu/Tianzhuang/Inner Mongolia, mixed in certain proportions. ·Huainan Fertilizer Factory uses bituminous coal from Yima, Henan.

I’ve learned that to gasify lignite, dry gasification methods are better, such as the Endress furnace, Shell, or GSP!

As an additional point, Shenmu coal can also be used in combination with other coals. It has a high moisture content, low sulfur content, and high ash content, but it is inexpensive, which helps to reduce costs to some extent

Regardless of the gasification technology, there are specific requirements regarding the type of coal; the claim that any type of coal can be used is actually misleading. The better the quality of the coal, the more stable the gasification process, which is beneficial for economic operation.