How to reduce the yield of dry gas and coke?
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How to reduce the yield of dry gas and coke? What are the methods?
1. Appropriate oil-to-agent ratio. 2. Appropriate catalyst activity. 3. Good atomization effect. 4. Low residual carbon and metal content in the raw materials. 5. The reaction temperature is appropriate (same as 1).
1. The appropriate addition of a terminator can reduce secondary reactions, thereby lowering the yield of dry gas and coke. 2. An appropriate amount of reactive stripping steam can be used to strip the oil and gas from the catalyst in the stripping section, thereby reducing coke production. 3. Properly operating the reabsorption oil can reduce dry gas production. 4. Optimize stable operating conditions to reduce the C3 and C4 content in dry gas.
1. Slightly reduce the reaction temperature. 2. Reduced catalyst activity. 3. Good atomization effect. 4. Use quench water, quench oil, etc. to terminate the secondary cracking reaction. 5. Reduce the reagent-to-oil ratio as well as the reprocessing ratio.
It’s not necessary to reduce the amount of coke to the minimum; the processing load of your entire plant is limited by the coking load in the regenerator. The residual carbon in the raw materials will also inevitably produce coke. Currently, the catalyzed coke content is generally 6-7%, while the dry gas content is generally 5-6%. The methods mentioned above are adjustment techniques for abnormal situations; once everything is running smoothly, there should be no issues with the yields of coke and dry gas. If it is truly necessary to reduce the dry gas production, the plant process can be changed, such as by adopting the TSRFCC process
In addition to what was mentioned by those upstairs, dry gas can be used as a pre-lifting medium.
Using deeply stabilized gasoline in the absorption section can also appropriately reduce the heavy components in the dry gas, thereby decreasing its volume; appropriate catalysts or additives can also be employed. Fundamentally, as someone mentioned above, change the process.
Increasing the reaction temperature, reducing the reaction pressure, and decreasing the circulation ratio can increase the yield of light products and reduce the carbon coke production. Reducing the amount of dry gas allows for a moderate reduction in the temperature at the bottom of the desorption tower; as the amount of rich gas changes, the absorption dose should be adjusted accordingly, and the reflux rates in the first and second sections of the absorption tower should be increased, while the temperature at the top of the absorption tower should be raised moderately
The key is to control the appropriate reaction temperature and reaction depth
Also, it is necessary to consider the heavy metal contamination of the catalyst.
Measures to reduce coking: 1. Use steam or dry gas to pre-raise the regenerated catalyst at the bottom of the riser. 2. Improve the atomization effect. 3. Slightly increase the regeneration temperature. 4. Improve stripping. 5. Install rapid separation facilities at the riser outlet; 6. Appropriately discard the oil slurry.