Is a water-cooled wall made of water-coal slurry better or are refractory bricks better? Please give some advice
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Our company plans to use water-coal slurry gasification in the near future, but we are unsure whether to opt for the Tsinghua furnace’s water-cooled wall plus quenching system, or a conventional refractory brick setup combined with quenching – which option should we choose? What are the reasons for choosing them? Could you please give some advice? O(∩_∩)O Thank you
If firebrick can meet the requirements, why use complicated water walls?
In fact, the range of coal types suitable for hot-wall water-coal slurry in China is relatively narrow; water-cooled walls do expand the range of coal types that can be used with water-coal slurry, and this constitutes a significant contribution to the gasification of water-coal slurry. The advantages of the water wall over refractory bricks are quite obvious.
It is said that the water wall can last around 8 years without needing to be replaced, while refractory bricks need to be replaced every 2 years. What is the actual situation?
Refractory bricks are also divided into cone-bottom bricks and fire-facing bricks; replacing them every two years is a fairly optimistic timeframe! Hehe
Our facility thinks refractory bricks are better
It can be said that each has its advantages; it depends on your financial situation.
Could you share any practical operational summaries or something like that? Thank you
Considering the service life of the water-cooled wall in Tsinghua furnaces combined with the quenching mode burners, the operating cycle per furnace (around 150 days), and the brick replacement cycle for refractory brick-based water-coal slurry gasifiers (around 10,000 hours), it is recommended to use the water-cooled wall in Tsinghua furnaces along with the quenching mode.
First, one needs to consider the scale – that is, how large the gasification capacity is. For large-scale operations, it is recommended to use the multi-nozzle opposed water-coal slurry gasification technology. A single gasifier can handle a large amount of coal; units capable of processing 3,000 tons of coal per day are already in operation, while those capable of handling 4,000 tons per day are under development. The maximum amount of coal that can be processed per day using a single nozzle is 2,000 tons, yet the investment required remains roughly the same. Therefore, for large-scale projects, the multi-nozzle opposed water-coal slurry gasification technology is recommended. For smaller-scale operations, the water-wall gasification technology is suggested. The reason for this is that the water-wall technology utilizes coal with a high ash melting point, and it does not require refractory bricks. As a result, the maintenance time for each gasifier is short, and the gasifier can be started quickly without the need for pre-heating. However, the current water-wall technology in China still has some shortcomings and requires further improvement.