The Venturi washing problem!
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If, during operation of the water-coal slurry gasifier, it is not possible to supply washing water to the venturi washer and the gasification section cannot be shut down for maintenance, what measures can be taken to minimize the problem of ash being carried in the semi-water gas?
The only option is to increase the load on the feed water pump of the scrubber in a short period of time, thereby increasing the amount of washing performed by the scrubber. Additionally, a large amount of washing is required for the shift condensate at the gasifier outlet to treat the syngas.
Control the ash content at the gasification outlet and increase the amount of water used for washing
I’m not sure whether the venturi scrubber mentioned by LZ is a combination of a venturi and a cyclone separator, or a combination of a venturi and a scrubbing tank
Increase the water supply to the scrubber tower as well as the external drainage flow, and increase the water added to the trays
Is this part of the water that important? I think it won’t affect production at least; at most, there will be a bit more ash in the process gas. This portion of water is responsible for the initial wetting and cleaning action. Ventricular water replenishment in scrubbers is hardly used by Shanxi Fengxi. Just as with the cyclone separator for venturi water replenishment, Shandong Guotai also stops feeding water into the venturi due to water present in the gasification furnace.
Increase the amount of water used for washing the exhaust gas; increase the drainage volume from the carbon scrubber tower; raise the amount of water used for washing
If the water supply is cut off, it is possible to increase the amount of water added to the trays and boost the drainage volume, thereby improving the water quality. Reduce the amount of ash. If it can’t be maintained, load reduction operations can also be carried out. The function of a Venturi is to humidify, remove dust, cool down, etc. However, some manufacturers do not use venturi tubes and still maintain the ash content of the syngas.
The comments on the 6th and 8th floors are correct. Eastman no longer uses venturi tubes.
If the process gas contains a high level of dust, it’s not good for the subsequent delivery pipelines and burners, right? In the case of a combination of a venturi and a cyclone separator, adding water helps to make it easier for dust in the process gas to be separated by the cyclone separator (the dust is attracted to the water droplets, allowing it to adhere more easily to the inner walls of the cyclone separator) ； In the case of a combination of a venturi and a wash tank, water replenishment is enabled only when the water in the wash tank needs to be replaced; most of the time, the water already in the tank is used in a circulation process to wash the process gas. This post was last edited by zhbb0206 on 2009-4-20 10:31.]
Generally, it has no impact. If you feel there is an effect, you can do the following: 1. Increase the amount of water used for cooling, as more water from the cooling chambers will still be returned to the scrubber tower, thereby serving to increase humidity； 2. The wash tower trays increase the water volume for washing, but it should not be increased too much to avoid affecting subsequent processes.
I thought: 1. The preferred option is to appropriately increase the water supply to the trays of the carbon scrubber tower. 2. The next step is to appropriately increase the amount of water used for quenching. 3. The last resort is to reduce the load! I think missing this water supply in the short term will likely have little impact.
Flushing water can be added at the syngas outlet of the gasifier, and the amount of water used for flushing the scrubber can be increased
Increase the water circulation in the system, as well as the amount of cooling water and the process condensate flowing through the wash tower trays.
Some manufacturers do not use venturi scrubbers, while others do; it is possible to remove ash without using a scrubber as well. If the scrubber becomes temporarily unusable, we can increase the water supply in other areas to control the ash content and the gas-to-water ratio; the specific procedures depend on the manufacturer’s design – some adjustments can be made at the scrubber tower, while others can be made at the gasification furnace