How to better address the issue of afterburning
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What adjustment measures can be taken by the oxygen-enriched regeneration system to address the issues of afterburning and secondary combustion
The possibility of this occurring during oxygen-enriched regeneration is quite low; it’s possible to add CO as a combustion aid on a regular basis
Add CO as an oxidizing agent daily, and adjust the main air flow accordingly based on the levels of oxygen and carbon monoxide in the flue gas. A deviation in the flow within the bed can also lead to incomplete combustion at the end of the furnace. While ensuring an appropriate ratio of fuel to oil, try to increase the temperature of the bed or raise the system pressure in order to increase the partial pressure of oxygen and thus ensure complete combustion of CO.
I would like to ask how to address the issue of afterburning while using as few oxidizers as possible
Adjusting to oxygen-deficient regeneration without afterburning is possible, but it is difficult to operate at the boundary between oxygen-rich and oxygen-deficient conditions
For oxygen-enriched regeneration, apart from adding combustion aids, adjusting the main air flow is the most effective and direct method. Flue gas nitrogen oxides increase with the addition of oxidizers.
Since your regeneration system is an oxygen-enriched regeneration, the reason for secondary combustion or even afterburning is that carbon and the carbon monoxide formed from carbon and oxygen cannot burn fully in the dense phase, resulting in combustion that occurs in the dilute phase. There are many specific reasons for secondary combustion, which need to be analyzed individually. For example, main wind deviation, excessively low bed level, severe carbon contamination in the raw material, excessive external heat-extraction fluidization air, and entry of unpurified air, etc.
When adding carbon monoxide as a combustion accelerator, attention should also be paid to the concentration of nitrogen oxides. After all, environmental regulations are now very strict; it’s better to make improvements through operational adjustments
First of all, it is necessary to ensure that the properties of the crude oil remain stable, without fluctuations in density from time to time； Additionally, the operating conditions of the regenerator should not vary too much; dense-phase combustion should be maintained as much as possible. If tail combustion leads to overheating, adding an oxidizer will have an immediate effect
The fastest method is to add CO as an oxidizing agent, adjust the amount of slag added, raise the bed temperature, and ensure sufficient air supply for complete combustion