[Q&A Question 067] 2018.03.08
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【Q&A Question 067】March 08, 2018: How to prevent the bed pressure drop from rising too rapidly during production operations? In actual production operations, improper handling can also cause the pressure drop across the bed to rise too rapidly ； The main issue is overheating of the catalyst bed, which leads to an intensified coking reaction and results in significant carbon buildup. In severe cases, the catalyst breaks down and its porosity decreases, causing an increase in pressure drop. Therefore, in actual production, it is necessary to strictly control the maximum temperature of the catalyst bed. (Unless otherwise specified, all questions and answers are based on hydrogenation units.) ) Due to the limitations on the number of posts in the “One Question per Day” section, “One Image per Day” has been moved to the registered devices section; you can access it through the directory I posted. For management purposes, if you need to access content from a few days ago, please go to the summary post below to enter the “My Registration Season” event – (Note: This event is currently underway in the Chemical Engineering section). https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=18978 For the daily questions section related to chemical engineering technology training in 2018: https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=1888971 For the daily image summary section related to registration equipment in 2018: https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=1888970 For the Q&A section related to hydrogen production and hydrogenation technologies in 2018: https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=1888968 For the daily questions section related to LNG technology in 2018: https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=1888973 For the Q&A section from 2017 (updates have started): https://bbs.hcbbs.com/thread-1657793-1-1.html For the daily questions section from 2017 (updates have started): https://bbs.hcbbs.com/thread-1657794-1-1.html For the daily image summary section from 2017: https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=1875160 For the list of daily questions related to LNG technology in 2017: https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=1804162 For the Q&A section from 2016 (updates are complete): https://bbs.hcbbs.com/thread-1597792-1-1.html
In actual production operations, improper handling can also cause the pressure drop across the bed to rise too rapidly； The main issue is overheating of the bed layer, which exacerbates coking reactions and leads to significant carbon accumulation. In severe cases, the catalyst gets damaged and its porosity decreases, resulting in an increase in pressure drop. Therefore, in actual production, it is necessary to strictly control the maximum temperature of the bed layer. Large fluctuations in total pressure can also cause damage to the catalyst; therefore, the rate of pressure changes must be strictly controlled during operation. Unless in an emergency, large pressure changes should be avoided in order to protect the catalyst. The control of other operating conditions, such as the light hydrogen to oil ratio, fresh hydrogen, and the amount of recycled hydrogen, should be aimed at suppressing coking during normal production. Especially when the supply of recycled hydrogen is interrupted, prompt action must be taken to prevent excessive coking that could block the bed.
In actual production operations, improper handling can also cause the pressure drop across the bed to rise too rapidly； The main issue is overheating of the bed layer, which leads to an intensified coking reaction and results in significant carbon buildup. In severe cases, the catalyst gets damaged and its porosity decreases, causing an increase in pressure drop. Therefore, in actual production, it is necessary to strictly control the maximum temperature of the bed layer. Large fluctuations in total pressure can also cause damage to the catalyst; therefore, the rate of pressure changes must be strictly controlled during operation. Unless in an emergency, large pressure changes should be avoided in order to protect the catalyst. The control of other operating conditions, such as the light hydrogen to oil ratio, fresh hydrogen, and the amount of recycled hydrogen, should be aimed at preventing coking during normal production. Especially when the supply of recycled hydrogen is interrupted, prompt action must be taken to avoid excessive coking that could block the bed.
:①It is mainly due to the overheating of the bed layer, which intensifies the coking reaction and leads to the accumulation of a large amount of carbon deposits, thereby increasing the pressure drop; therefore, it is necessary to strictly control the maximum temperature of the bed layer. ②Large fluctuations in total pressure
In actual production operations, improper handling can also cause the pressure drop across the bed to rise too rapidly； The main issue is overheating of the bed layer, which exacerbates coking reactions and leads to significant carbon accumulation. In severe cases, the catalyst gets damaged and its porosity decreases, resulting in an increase in pressure drop. Therefore, in actual production, it is necessary to strictly control the maximum temperature of the bed layer. Large fluctuations in total pressure can also cause damage to the catalyst; therefore, the rate of pressure changes must be strictly controlled during operation. Unless in an emergency, large pressure changes should be avoided in order to protect the catalyst. The control of other operating conditions, such as the light hydrogen to oil ratio, fresh hydrogen, and the amount of recycled hydrogen, should be aimed at suppressing coking during normal production. Especially when the supply of recycled hydrogen is interrupted, prompt action must be taken to prevent excessive coking that could block the bed.
In actual production operations, improper handling can also cause the pressure drop across the bed to rise too rapidly； The main issue is overheating of the bed layer, which leads to coking. In the coking and hydrogen production unit of Changyi Petrochemical, this exacerbates the reaction process, resulting in significant carbon buildup. In severe cases, the catalysts get damaged and their porosity decreases, which in turn causes an increase in pressure drop. Therefore, in actual production, it is necessary to strictly control the maximum temperature of the bed layer. Large fluctuations in total pressure can also cause damage to the catalyst; therefore, the rate of pressure changes must be strictly controlled during operation. Unless in an emergency, large changes in pressure should not be made in order to protect the catalyst. The control of other operating conditions, such as the light hydrogen to oil ratio, fresh hydrogen, and the amount of recycled hydrogen, should be set in a way that helps to prevent coking during normal production. Especially when the supply of recycled hydrogen is interrupted, prompt action must be taken to avoid excessive coking that could block the bed.
In actual production operations, improper handling can also cause the pressure drop across the bed to rise too rapidly； The main issue is overheating of the bed layer, which exacerbates coking reactions and leads to significant carbon accumulation. In severe cases, the catalyst gets damaged and its porosity decreases, resulting in an increase in pressure drop. Therefore, in actual production, it is necessary to strictly control the maximum temperature of the bed layer.
Answer: In actual production operations, improper handling can also cause the pressure drop across the bed to rise too rapidly； The main issue is overheating of the bed layer, which exacerbates the coking reaction and leads to significant carbon buildup. In severe cases, the catalyst gets damaged and its porosity decreases, resulting in an increase in pressure drop. Therefore, in actual production, it is necessary to strictly control the maximum temperature of the bed layer
:①It is mainly due to the overheating of the bed layer, which intensifies the coking reaction and leads to the accumulation of a large amount of carbon deposits, thereby increasing the pressure drop; therefore, it is necessary to strictly control the maximum temperature of the bed layer. ②Large fluctuations in total pressure can also cause catalytic damage
In actual production operations, improper handling can also cause the pressure drop across the bed to rise too rapidly； The main issue is overheating of the bed layer, which exacerbates coking reactions and leads to significant carbon accumulation. In severe cases, the catalyst gets damaged and its porosity decreases, resulting in an increase in pressure drop. Therefore, in actual production, it is necessary to strictly control the maximum temperature of the bed layer. Large fluctuations in total pressure can also cause damage to the catalyst; therefore, the rate of pressure changes must be strictly controlled during operation. Unless in an emergency, large pressure changes should be avoided in order to protect the catalyst. The control of other operating conditions, such as the light hydrogen to oil ratio, fresh hydrogen, and the amount of recycled hydrogen, should be aimed at suppressing coking during normal production. Especially when the supply of recycled hydrogen is interrupted, prompt action must be taken to prevent excessive coking that could block the bed.
Answer: 1. It is mainly due to overheating of the bed layer, which leads to an intensified coking reaction and the accumulation of large amounts of carbon deposits, resulting in an increase in pressure drop; therefore, it is necessary to strictly control the maximum temperature of the bed layer. 2、Large fluctuations in total pressure can also cause damage to the catalyst; therefore, the rate of pressure increase or decrease must be strictly controlled. Under normal circumstances, large changes in pressure should not be made, unless it is an emergency, in order to protect the catalyst. 3. Control of other operating conditions such as the hydrogen-to-oil ratio, amount of fresh hydrogen, amount of recycled hydrogen, and other parameters. During normal production, it should be adjusted in a direction that suppresses coking. Especially when the circulating hydrogen is interrupted, it should be addressed promptly to prevent coking and blockage of the bed.