Can chemical industry waste gas be introduced into a circulating fluidized bed combustion system?
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Our plant generates about 10,000 m3/h of chemical waste gases, whose main components are H2 and CO, with a calorific value of over 10,000 KJ/Kg. Since it is a hydrogen-rich fuel, its diffusion rate is very fast, and hydrogen as well as CO are highly flammable; it is uncertain whether it can be used in circulating fluidized bed boilers for combustion in order to save coal. Do any of you sea friends have experience with modifications in this area? Waiting for good news! This post was last edited by Refiner on 2009-3-12 12:59.]
I think it can be utilized, but it cannot lead directly to the furnace. Could it be used to heat the air under the bed? It’s just my suggestion, for reference only! If there are any issues, please let me know!
Such waste gas emissions are not only a waste but also cause severe environmental pollution; it is recommended to carry out process improvements promptly! I’m not sure what production processes you use. If there are constraints due to factors such as concentration or temperature and pressure, or other economic or process-related limitations, is it possible to use separation and concentration methods to obtain gas with a higher concentration before feeding it back into the furnace?
Is it a methanol plant? This portion of gas can be used as fuel gas. As for whether it can be directly fed into a circulating fluidized bed, I’ve not seen any examples of this; theoretically, it should be possible. If not, simply build a new gas boiler – that’s all there is to it:lol
Yes, releasing such waste gas directly into the atmosphere is indeed a bit wasteful and pollutes the air. Our dry gas can be used directly for combustion in boilers; we haven’t come across this type of gas before, so I’d like to hear everyone’s opinions! !
I think it can be used as fuel for circulating fluidized bed boilers; I have seen drawings of boilers that burn blast furnace gas. To prevent explosions caused by boiler combustion, in addition to giving due consideration to the layout of the burners, the design should include explosion-proof doors, reliable ignition control procedures and flame-out protection devices. It should also be equipped with the following protective interlock devices: (1) In the event that all exhaust fans lose power, it should be possible to automatically cut off all air supply and fuel supply ； (2) When all the exhaust fans lose power, all fuel supply is automatically cut off ； (3) When these gas pressures fall below the specified values, the gas supply is automatically cut off. Thorough purging must also be carried out before igniting the boiler. When all the aforementioned safety hazards are properly taken into account, the operation of the boiler should be safe.
Thank you all for your suggestions, fellow sailors! Our company produces methanol and acetic acid; the chemical waste gases mainly consist of the off-gases from methanol synthesis and the high-pressure exhaust gases from acetic acid production. If anyone has relevant modification materials, could you send them to me? Thank you again! ! ! :victory:
Theoretically it is possible, but there are difficulties in practice, as both H2 and CO are explosive gases. It is challenging to control the amount of air entering the burner so that it remains within the explosion limits of these gases, and moreover the gas concentration fluctuates – how can this be controlled?
It is feasible both from an environmental protection and energy-saving perspective. For specific design options, one can consult various boiler manufacturers, as there are precedents for this.
Sure, there are existing fluidized-bed boilers that use phosphorus pentoxide exhaust gas; if you want, I can help you get in touch with them.
If this syngas is produced in large quantities, it can be fed into a gas turbine to generate electricity. It is not impossible to use it in a fluidized bed boiler, but at least modifications to the burner are required; it is mainly a matter of cost.
It is no problem to use it in boiler combustion; it can serve as an auxiliary fuel, and after normal ignition, it can gradually replace part of the traditional fuel without any issues. Safety issues are something that should be taken into consideration, mainly after ignition or shutdown; normal operation poses no problems.
Consider adding a waste heat boiler with combustion； It’s similar to a waste heat boiler that uses gas from blast furnaces; it doesn’t have to be a circulating fluidized bed as you mentioned
It can enter combustion, but burners need to be added; furthermore, it can only be introduced when the furnace temperature is above 780 degrees, otherwise it may cause an explosion； Furthermore, the gas supply must be turned off before cooling down to ensure safety ； Our factory has been using it for many years
Theoretically, this type of exhaust gas is feasible, but great care must be taken in practice. It is recommended to dilute it with cold air before introducing it into the boiler to prevent explosive combustion.
It can be fed into a fluidized bed boiler for combustion; the key lies in the quality and performance of the burner, as well as the implementation of safety measures to prevent backflow and explosions.
The high hydrogen content and carbon monoxide concentration allow it to be compressed into a liquid fuel; it would be a shame to waste it. It mainly depends on whether such manufacturing capabilities exist! !
The coal-fired boilers used in our plant incorporate a large amount of methanol off-gas in their fuel mixture. This system has been in use for three years now, and there have been no issues such as boiler shutdowns that were once a concern; merely the natural gas burners were replaced with the current type of burners. Therefore, it is technically feasible to burn the waste gas from your plant in a circulating fluidized bed, and there should be no engineering problems.
I think it would be better to arrange another furnace specifically for burning this waste gas. On the one hand, the main boiler does not need to be modified, so normal production is not affected; a new boiler can then be installed based on the amount of waste gas generated. The technical requirements for this are low. Additionally, the safety controls for the waste gas boiler can be operated independently, thereby reducing potential safety risks.
I think it would be better to use another waste gas furnace, as neither the induced draft fan nor the blower of the circulating fluidized bed boiler can meet the requirements for drawing in combustion exhaust gases and creating turbulence; moreover, the fluidized bed has a membrane wall structure, making modifications difficult.