Which is more suitable for chemical production: dry coal powder gasification or water coal slurry gasification?
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Which is more suitable for chemical production: dry coal powder gasification or water coal slurry gasification? Since the ratio of H2 to CO in the syngas produced by dry coal powder gasification differs slightly from that in the syngas produced by water-coal slurry gasification, especially due to the large difference in H2O(g) content, and since processes such as the Shell gasification method do not employ a quench chamber, what impact does this have on the subsequent shift reactions? It is mainly industries such as ammonia synthesis; how do industries make up for or deal with this?
Slurry coal gasification is a bit better; Shell still needs to add additional treatment equipment
They should all be suitable for chemical production; it’s just a matter of considering the initial investment and operating costs, comparing them with each other, choosing the option that fits the factory’s actual conditions, addressing energy consumption issues based on those conditions, and finally deciding on which process to use. .
Water-coal slurry is a suitable option; its moisture content meets the requirements of the chemical industry. Dry powder is suitable for the power generation industry in IGCC applications
From a process perspective, water-coal slurry is more suitable for chemical production, especially in ammonia synthesis and methanol synthesis projects.
The dry powder gasification shell operates in a waste-heat recovery mode, making it suitable for use with IGCC, GSP, and space furnaces that employ a quenching process; it is also well-suited for use in chemical manufacturing. The powder coal gasification technology using a quenching process sacrifices some thermal efficiency, but it reduces equipment investment and improves operational stability; meanwhile, the syngas contains a large amount of water vapor. Combining powder coal gasification with quenching is the most advantageous approach for producing syngas.
All are suitable; coal water slurry loses some heat, and additional steam is required for the conversion process.
Either of the two processes can be used; it mainly depends on the type of coal you have. If the slurry concentration is less than 60%, the water-coal slurry technique cannot be applied, as factors such as the water that evaporates and the additives used will result in high costs；
Therefore, based on the above discussions, both processes are viable; the key decision factor is the type of coal and cost. But in terms of the process itself, for companies like Shell, when the syngas moves upward, a waste heat exchanger is necessary; whereas when it moves downward, it can either use a waste heat exchanger or a quench chamber. Wouldn’t it be advantageous to have both the syngas and the slag move downward? !
It mainly comes down to the compatibility between coal types and gasification technologies. It’s possible that neither of the two is suitable for the local coal type.