One question per day: Coal-to-oil and olefins discussion forum, 2017.12.17
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This post was last edited by Xibei Guyan on 2017-12-17 at 16:36. 3.jpg Participation: Reward of 5 Wealth； Correct answer: Reward of 10 wealth points ； Note: This post is valid for 48 hours. Question: What is the purpose of nitrogen sealing in the cold box of the (DMTO) olefin separation unit? To prevent negative pressure! Nitrogen is used to maintain a positive pressure to prevent air from entering; air contains water, which condenses at the low temperatures in the cold box, thereby affecting heat transfer and leading to oxidation and corrosion of the heat exchanger! Note: The answer will be announced automatically in two days!
Prevent negative pressure! Nitrogen is used to maintain a positive pressure to prevent air from entering; air contains water, which condenses at the low temperatures in the cold box, thereby affecting heat transfer and leading to oxidative corrosion of the heat exchanger
The insulation material filled inside the cold box is packed with air, and at low temperatures, the drop in air pressure between the insulation materials creates a negative pressure inside the cold box. It causes the cold box to collapse. If the cold box is not properly sealed, allowing moist air to enter, the insulation material becomes damp, clumps together, and can damage the equipment pipelines; furthermore, the heat loss of the system increases. Therefore, a protective gas is introduced into the cryogenic box to maintain a slightly positive pressure inside it
Answer: The insulation material filled inside the cold box is packed with air, and at low temperatures, the drop in air pressure between the insulation layers creates a negative pressure inside the cold box. It causes the cold box to collapse. If the cold box is not properly sealed, allowing moist air to enter, the insulation material becomes damp, clumps together, and can damage the equipment pipelines; furthermore, the heat loss of the system increases. Therefore, a protective gas is introduced into the cryostat to maintain a slight positive pressure inside it.
Prevent negative pressure! Nitrogen is used to maintain a positive pressure to prevent air from entering; air contains water, which condenses at the low temperatures in the cold box, thereby affecting heat transfer and leading to oxidation and corrosion of the heat exchanger!
1. Isolate from air to prevent oxygen from entering the system. 2. Prevent the leakage of toxic, harmful substances or materials that could cause damage to the environment
Prevent negative pressure. Nitrogen is used to maintain a positive pressure to prevent air from entering; air contains water, which condenses at the low temperatures in the cold box, thereby affecting heat transfer and causing oxidation and corrosion of the heat exchanger.
Prevent negative pressure! Nitrogen is used to maintain a positive pressure to prevent air from entering; air contains water, which condenses at the low temperatures in the cold box, thereby affecting heat transfer and leading to oxidation and corrosion of the heat exchanger!
Ensure that the compressor outlet temperature remains below 90 degrees, thereby reducing the likelihood of polymerization and scaling inside the machine.
Prevent negative pressure! Nitrogen is used to maintain a positive pressure to prevent air from entering; air contains water, which condenses at the low temperatures in the cold box, thereby affecting heat transfer and leading to oxidation and corrosion of the heat exchanger!