How to solve the ash accumulation in the SGC section of the shell gasification unit?
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Due to ash accumulation in the SGC section of the Shell gasification unit, it prevents the unit from operating for extended periods. Is there any effective solution?
Isn’t there any device like a soot blower? Gasification processes that use the waste boiler process are estimated to have this problem.
At present, there are over twenty Shell gasifiers in our country, with more than a dozen of them in operation. However, the problem of dust accumulation in the gasifier pipelines has become a key factor restricting the long-term stable operation of these systems. Apart from using coal as a blending material, it seems that there is no better solution available in China; moreover, using coal as a blending material is costly and involves a significant amount of work. Is it a problem with our operation, or is it an issue with Shell’s design? Has our country really become a testing ground for Shell? Let’s discuss how this problem can be completely solved Share our opinions, discuss together, and progress as a whole.
Manually control the striker and strike it several times. Before starting the machine, check that both the sealed nitrogen and the power gas used by the striker are in good condition. Ensure that the ratio of quenching gas is properly controlled; at the bend from the vaporization furnace to the SGC, the temperature should be maintained at an appropriate level (in other words, the quenching ratio needs to be well controlled)
3# hnaylhj: The waste boiler can be equipped with a certain number of pneumatic knocking ash removal devices as needed, to carry out vibration-based ash removal on a regular or irregular basis.
To mitigate the effects of ash accumulation, the role of controlling the quenching ratio seems to need to be reassessed; making optimal use of the capacity of the circulation pump is likely to be the key measure to prevent ash buildup and overheating in the SGC
There are many such posts in the forum: 1. Ensure an effective rapid cooling effect. 2. Ensure that the soot-blowing system of the distribution frame functions properly. 3. Control the furnace temperature. 4. The type of coal is crucial. 5. The shape of the ash particles also needs to be taken into account; it’s not necessary for them to be as small as possible – appropriately larger particles have a self-cleaning effect. 6. Metal content: High-temperature gasification occurs inside the furnace, while ash agglomeration takes place during the cooling phase
Since the operation of shell gasifiers began, it seems that the problem of ash accumulation in the SGC section still exists in some manufacturers and even affects long-term production. However, this is no longer an unsolvable issue; it merely introduces new problems, namely more severe wear of the ducts. It is necessary to consider various factors in order to optimize measures for preventing ash accumulation and duct wear. One cannot focus on solving production-related technical problems while neglecting other aspects, as that would lead to the continuous emergence of new problems as existing ones are resolved. . .
A certain device once attempted to reduce the water-oxygen ratio to 0 and operated continuously for 3 days, during which the temperature of the superheated steam increased from 360 degrees to 390 degrees. Give it a try; there might be a pleasant surprise.
A high quenching ratio contributes to increased wear of the conduits; based on the failure analysis of devices where wear was observed, this wear can be addressed through regular maintenance as well as drying or other methods to enhance strength in accordance with specified requirements. A relatively high quenching ratio within the range required by BDEP is not a major factor
For certain coal types, stopping the supply of steam to the gasifier can reduce SGC ash accumulation and lower the temperature at point 13Ti0018. Regarding this issue, discussions were held with relevant technical personnel, and the final conclusion seems to be that the addition of water vapor increases the reactivity of the coal powder and reduces the particle size of the coal ash, thereby reducing the self-cleaning ability of the coal ash. Here, everyone can continue the discussion on why not adding steam helps prevent ash buildup in SGC, and it seems that whether steam is added or not has little impact on the gasification temperature and composition.