Problem of the heat blower in the WSA unit not generating sufficient airflow
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Recently, the WSA unit was overhauled because the hot air volume from its heat exchanger was insufficient; this overhaul included cleaning and screening of the burners, waste heat boilers, and catalysts. During the cooling process, it was observed that the hot air volume increased on its own, and there were also blockages in the burners and waste heat boilers. After the unit was restarted, the air volume was normal, but 48 hours after acidic gas was introduced, the air volume again dropped. However, the bearing temperatures did not rise, and the overall situation returned to what it was before the overhaul. Is there anyone who can help me determine which part is causing the problem?
Could you provide a detailed introduction to your WSA device?
Our WSA is used to treat methanol-containing acidic gas; it is designed to handle 3100 Nm3/h of acidic gas and 4100 Nm3/h of hot air. The hydrogen sulfide concentration varies considerably, with these fluctuations being periodic – ranging from a minimum of 6 mg/l to a maximum of 26 mg/l
Do you have any control parameters for the temperature and pressure of acidic gases in the methanol wash process? I think it might be because the hydrogen sulfide wasn’t burned properly, resulting in a high methanol content. System resistance increases. I’m very interested in learning about your process.
There are no control parameters for the temperature of the acidic gases derived from methanol; although there are parameters for pressure, it is generally below 0.05 Mpa due to large fluctuations in gas volume. I would like to know what relationship exists between the temperature of these acidic gases and the combustion process
Is it related to the operation of the condenser pressure difference control valve? There is a mutual influence between our cold and hot air fans.
The pressure difference control valves of the condenser are generally fixed, and the pressure difference is also 4 mbar. Currently, we have replaced the burners and the waste heat boiler (increasing the heat exchange area), and the system resistance is much better than before. However, new problems have arisen: the steam cannot be connected to the main network, and the entire incinerator experiences slight vibrations.
Do your fans have frequency control devices? How many cold fans and hot fans do you have?
I’m not sure whether what was said on the 7th floor about the steam not being connected to the network refers to the steam pressure in the system being lower than that in the pipeline network. If that’s the case, it might be due to insufficient thermal load in the incinerator; adding some additional fuel gas could help increase the thermal load. The vibration in the incinerator could be caused by insufficient hot air supply, valves that are not closed properly, or airflow erosion. We have encountered similar problems before, and they were resolved once the load was increased
An increase in the temperature of the combustion air leads to an increase in its viscosity, which in turn raises the resistance to air flow. Since the power of the fan remains constant, this results in a reduction in the fan’s capacity to move air; lowering the air temperature helps significantly. Give it a try.
There is also a very simple method: just add another fan to increase the air supply capacity. Haha!
What exactly is causing the heat blower not to produce enough airflow?