[Q&A Question 213] 2017.08.01
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【Q&A Question 213】August 01, 2017: What is the phenomenon of interruption in reaction injection water? How to operate it? The reference answers will be visible after responding; points are awarded by identifying the key points. (Unless otherwise specified, all questions and answers are based on hydrogenation units.) ) After the injection of reaction water is interrupted, the following situations occur: ① The inlet and outlet temperatures of the high-pressure air cooler increase ； ②External water supply interrupted; the liquid level indicator in the water injection tank drops ； Injection is interrupted, the injection volume decreases or returns to zero, and the high-level interface indicator drops ； ③The concentrations of NH3 and H2S in the recycled hydrogen increase ； ④The reaction temperature decreases ； ⑤Prolonged cessation of water supply can cause the air-cooled ammonium salts to precipitate and become clogged, increasing the system pressure drop. Handling: ① If the injection pump stops operating, immediately close the outlet valve of that pump to prevent high pressure from leaking into the low-pressure system, and start the backup pump right away while keeping the high-level cut-off point under control ； ②Water supply is interrupted; contact the upstream facility to supply water promptly ； ③If there is a long-term water outage, reduce the feed or stop feeding it. Scoring criteria: 2 Wealth points for incorrect responses; *incomplete* answers earn 3–8 points. 10 Wealth points are given for correct answers accompanied by detailed explanations; responses that are correct but lack sufficient details earn 15–20 Wealth points. Please score according to these criteria. Note: If there are editing records after answering, only points will be awarded to those who participated. For continuous malicious spamming, 2 points will be deducted each time, with no upper limit. Pure numbers, pure emojis, or random letters that have no relation to the answer are all considered malicious spamming; points will start to be deducted after three warnings. 2017 Q&A Summary Thread (updates have begun) http://bbs.hcbbs.com/thread-1657793-1-1.html 2017 Daily Question Summary Thread (updates have begun) http://bbs.hcbbs.com/thread-1657794-1-1.html 2016 Q&A Summary Thread (updates completed) http://bbs.hcbbs.com/thread-1597792-1-1.html Petrochemical Sector – “Creative Ideas for Energy Saving” Campaign (the second phase is in full swing) http://bbs.hcbbs.com/thread-1666758-1-1.html (Source: Haichuan Chemical Industry Forum Website)
①Increase in the inlet temperature of the high-pressure air cooler； ②Note: Due to the reduction in the flow rate of the medium inside the high-pressure air cooler following a disruption in the water supply, the outlet temperature of the high-pressure air cooler may decrease ； ③The water injection flow rate indicates zero ； ④The concentrations of NH and H2S in the recycled hydrogen increase ； ⑤The reaction temperature decreases ； ⑥Prolonged cessation of water supply can cause the air-cooled ammonium salts to precipitate and become clogged, resulting in an increase in system pressure drop
①Increased inlet and outlet temperatures of high-pressure air cooling； ②The water injection flow rate indicates zero ； ③The concentrations of NH3 and H2S in the circulating hydrogen increase ； ④The reaction temperature decreases ； ⑤Prolonged cessation of water supply can cause the air-cooled ammonium salts to precipitate and become clogged, increasing the system pressure drop. Handling: ① Pump failure – switch to the backup pump to maintain production ； ②Water supply interrupted; contact quickly for water supply ； ③If water supply is interrupted for an extended period, reduce the feed rate or stop feeding altogether ； ④During short-term water outages, the reaction temperature is appropriately increased by releasing waste hydrogen to maintain conversion rate and production. Generally, the stop time for water injection should not exceed 4 hours. After resuming water injection, the maximum injection volume should be maintained for a period of time. A device that allows for sequential branch injection can be used to flush each branch for 10 minutes.
After the injection of reaction water is interrupted, the following situations occur: 1. The temperatures at the inlet and outlet of the high-pressure air cooler increase； 2. The water injection flow rate indicates zero ； 3. Increased concentrations of ammonia and hydrogen sulfide in the circulating hydrogen ； 4. Reaction temperature decreases ； 5. Prolonged water outages can cause air-cooled ammonium salts to crystallize and accumulate, leading to increased system pressure drop. Methods for handling interruptions in reactive injection water: 1. In the event of a pump failure, switch to a backup pump to maintain production ； 2. Water supply interrupted; contact promptly for water supply ； 3. If water supply is interrupted for an extended period, reduce the feed rate or stop feeding altogether ； 4. During short-term water supply interruptions, increase the reaction temperature appropriately to maintain conversion rate and production ； Generally, the stop time for water injection should not exceed 4 hours. After resuming water injection, the maximum injection rate should be maintained for a period of time. Devices that allow separate branch injections can be used to flush each branch for 10 minutes.
: Phenomenon: ① Increased temperatures at the inlet and outlet of the high-pressure air cooler； ②The water injection flow rate indicates zero ； ③The concentrations of NH3 and H2S in the circulating hydrogen increase ； ④The reaction temperature decreases ； ⑤Prolonged cessation of water supply can cause the air-cooled ammonium salts to precipitate and become clogged, increasing the system pressure drop. Handling: ① Pump failure – switch to the backup pump to maintain production ； ②Water supply interrupted; contact quickly for water supply ； ③If water supply is interrupted for an extended period, reduce the feed rate or stop feeding altogether ； ④During short-term water outages, the reaction temperature is appropriately increased by releasing waste hydrogen to maintain conversion rate and production. Generally, the stop time for water injection should not exceed 4 hours. After resuming water injection, the maximum injection volume should be maintained for a period of time. A device that allows for sequential branch injection can be used to flush each branch for 10 minutes.
After the interruption of the reactive injection water, the following situations occur: ① The inlet and outlet temperatures of the high-pressure air cooler increase； ②The water injection flow rate indicates zero ； ③The concentrations of NH3 and H2S in the circulating hydrogen increase ； ④The reaction temperature decreases ； ⑤Prolonged cessation of water supply can cause the air-cooled ammonium salts to precipitate and become clogged, increasing the system pressure drop. Handling: ① Pump failure – switch to the backup pump to maintain production ； ②Water supply interrupted; contact quickly for water supply ； ③If water supply is interrupted for an extended period, reduce the feed rate or stop feeding altogether ； ④During short-term water outages, the reaction temperature is appropriately increased by releasing waste hydrogen to maintain conversion rate and production. Generally, the stop time for water injection should not exceed 4 hours. After resuming water injection, the maximum injection volume should be maintained for a period of time. A device that allows for sequential branch injection can be used to flush each branch for 10 minutes.
After the interruption of the reactive injection water, the following situations occur: ① The inlet and outlet temperatures of the high-pressure air cooler increase； ②The water injection flow rate indicates zero ； ③The concentrations of NH3 and H2S in the recycled hydrogen increase ； ④The reaction temperature decreases ； ⑤Prolonged cessation of water supply can cause the air-cooled ammonium salts to precipitate and become clogged, increasing the system pressure drop. Handling: ① Pump failure – switch to the backup pump to maintain production ； ②Water supply interrupted; contact quickly for water supply ； ③If water supply is interrupted for an extended period, reduce the feed rate or stop feeding altogether ； ④During short-term water outages, the reaction temperature is appropriately increased by releasing waste hydrogen to maintain conversion rate and production. Generally, the stop time for water injection should not exceed 4 hours. After resuming water injection, the maximum injection volume should be maintained for a period of time. A device that allows for sequential branch injection can be used to flush each branch for 10 minutes.
Phenomena: 1. The high-pressure cut-off value decreases. 2. The inlet temperature of the air cooler rises. 3. The flow rate of the external deionized water is zero. 4. The system pressure difference decreases. Action taken: 1. Immediately analyze the cause; if it is due to external factors, seek guidance from the dispatch team right away. If it is due to the water injection pump, immediately activate the backup pump. 2. If water injection cannot be restored temporarily, manually shut off the high-level control valve to prevent oil from entering the acidic water. 3. If recovery is not achieved after a long time, pay attention to the pressure drop in the reaction system. If the pressure drop continues to increase, stop the process by shutting off the feed.
After the interruption of the reactive injection water, the following situations occur: ① The inlet and outlet temperatures of the high-pressure air cooler increase； ②The water injection flow rate indicates zero ； ③The concentrations of NH3 and H2S in the circulating hydrogen increase ； ④The reaction temperature decreases ； ⑤Prolonged cessation of water supply can cause the air-cooled ammonium salts to precipitate and become clogged, increasing the system pressure drop. Handling: ① Pump failure – switch to the backup pump to maintain production ； ②Water supply interrupted; contact quickly for water supply ； ③If water supply is interrupted for an extended period, reduce the feed rate or stop feeding altogether ； ④During short-term water outages, the reaction temperature is appropriately increased by releasing waste hydrogen to maintain conversion rate and production. Generally, the stop time for water injection should not exceed 4 hours. After resuming water injection, the maximum injection volume should be maintained for a period of time. A device that allows for sequential branch injection can be used to flush each branch for 10 minutes.
Phenomenon: ① Increased temperatures at the inlet and outlet of the high-pressure air cooler； ②The water injection flow rate indicates zero ； ③The concentrations of NH3 and H2S in the circulating hydrogen increase ； ④The reaction temperature decreases ； ⑤Prolonged cessation of water supply can cause the air-cooled ammonium salts to precipitate and become clogged, increasing the system pressure drop. Handling method: ① If the pump fails, switch to the backup pump to maintain production ； ②Water supply interrupted; contact quickly for water supply ； ③If water supply is interrupted for an extended period, reduce the feed rate or stop feeding altogether ； ④During short-term water outages, the reaction temperature is appropriately increased by releasing waste hydrogen to maintain conversion rate and production. Generally, the stop time for water injection should not exceed 4 hours. After resuming water injection, the maximum injection volume should be maintained for a period of time. A device that allows for sequential branch injection can be used to flush each branch for 10 minutes.
After the interruption of the reactive injection water, the following situations occur: ① The inlet and outlet temperatures of the high-pressure air cooler increase； ②The water injection flow rate indicates zero ； ③The concentrations of NH3 and H2S in the circulating hydrogen increase ； ④The reaction temperature decreases ； ⑤Prolonged cessation of water supply can cause the air-cooled ammonium salts to precipitate and become clogged, increasing the system pressure drop.