Is the exhaust fan in your workshop powered by electricity or generated power?

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This post was last edited by beyondbeiyang on 2017-3-16 at 17:50. The catalytic unit 3 consists of the flue gas fan, the main fan, and the motor/generator; since it can utilize the high-temperature flue gas generated during catalyst regeneration to perform work, it saves a large amount of electrical energy and is therefore widely used. High-quality smoke extractors can achieve a recovery efficiency of up to 130% (the ratio of the extractor’s power to that of the fan). However, due to issues in design and practical application, the efficiency of such extractors often deviates from this value, forcing the use of electric motors to compensate for the shaft power. In simple terms, the power of the flue gas extractor is related to the volume, temperature, and pressure of the flue gas; within a certain range, as temperature and pressure increase, the power of the extractor also increases. By focusing on these two aspects, the efficiency of the flue gas extractor can be improved through the following technical modifications: 1. The flue gas emerging from the regenerator has three main destinations: one is the flue gas extractor, another is it enters the chimney via double-acting slide valves, and the third is the amount of gas that leaks through the triple swirl mechanism. To allow the flue gas to flow through the ducts, it is necessary to reduce the opening degree of the double-acting slide valve as much as possible, while avoiding any fluctuations in pressure in both devices ； The increase or decrease in the leakage rate of the triple rotor depends on the separation efficiency of the rotor, and it is generally not taken into consideration. 2. Verification of flue gas inlet temperature: It is necessary to check whether the inlet temperature of the flue gas during actual operation meets the design value specified for the flue gas burner; if not, insulation measures such as an internal thermal insulation lining or external insulation fibers can be applied to the flue gas ducts. A petrochemical company installed an DN80 air pipeline in the flue gas duct to burn the carbon monoxide present in the flue gas, thereby increasing its temperature. (This entry belongs to the ‘the more skilled, the bolder’ series; use with caution.) ) 3. Pressure at the inlet and outlet of flue gas: The higher the inlet pressure of the flue gas, the lower the outlet pressure, and the higher the efficiency of the flue gas fan. Flue gas flows from the regenerator to the flue gas fan inlet; factors that affect the flue gas pressure include the regenerator pressure, cyclone separator, external heat exchanger, and high-temperature butterfly valve. Therefore, without causing fluctuations, opening the high-temperature butterfly valve wider can reduce the pressure drop at the flue gas inlet, thereby increasing the pressure at that inlet. The pressure of the smoke exiting the smoke extractor should be low, that is, the backpressure of the smoke extractor should be low. The main factors affecting the backpressure level include the water seal tank, flue gas waste heat boiler, and the operating pressure for flue gas desulfurization. Check whether the pressure drop in the water seal tank is excessive ； Preheating boilers can also experience pressure drops due to pipe scaling, and so soot blowing should be carried out promptly. If there are other valves or orifice plates on the flue gas pipeline, increase their opening size and the opening ratio as appropriate. I am not very knowledgeable, so I’m trying to contribute my humble insights. There are still some issues mentioned in this article for which no solutions have been found; if you have any good ideas or other questions, feel free to leave a comment and discuss them!