Comparison of hydrogenation water injection volume, injection methods, and effects
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How to determine the water injection volume for hydrogenation units； Common injection points are found in vertical pipes and horizontal pipes; which water injection method is better? ； What type of structure is effective for the injection point: handshake
The amount of water injected during the reaction affects the content of impurity components in the circulating hydrogen. Ammonia in the gas phase is typically removed by adding 1% of the volume of feed oil as water, based on a nitrogen content of 20 ppm in the feed oil. A more common approach is to control the amount of condensate water added by ensuring that the mass content of hydrogen sulfide and ammonia in the acidic water, ranked by high scores, does not exceed 8%.
Our injection location is the horizontal pipe section.
We have water injection points in the horizontal pipe sections, as well as in the vertical pipe sections. Generally, reverse water injection is used to ensure thorough mixing.
The water injection volume is generally set at 6% to 10% of the reaction feed volume, and vertical injection is used; the water is injected separately at various points before entering the air cooler, which helps to ensure uniform water distribution. An adequate amount of water injection can reduce corrosion in the air-cooling system as well as tube bundle blockages. However, too much water injection will place a heavy load on the acidic gas treatment units downstream, and it is also detrimental to overall energy savings and consumption reduction. Therefore, the appropriate amount of water to inject must be determined through long-term practical experience.
According to the explanation on page P661 of \"Hydroprocessing Technology and Engineering\" (Sinopec Press, edited by Li Dadong), injecting water into the reaction process will more or less affect the content of impurity components in the circulating hydrogen. Ammonia in the gas phase is typically removed by adding 1% of the volume of the feed oil as water, based on a nitrogen content of 200 μg/g in the feed oil. A more common approach is to control the amount of condensate water added by ensuring that the mass content of hydrogen sulfide and ammonia in the acidic water, ranked by high scores, does not exceed 8%. ※200μg/g = 200ppm. I wonder which one makes sense? ? ? :Q
Sorry, it should be 200 ppm; I was careless just now
The water injection volume is 5–8% of the feed volume
We use horizontal pipe injection; in practice, the amount of water we inject is less than 1% of the mass of the raw material.
The location of the water injection points depends mainly on the temperature at which the ammonium salts crystallize. After heat exchange with the feed oil, the resulting oil enters the air cooler; generally, demineralized water is injected before it reaches the air cooler. If the temperature of the oil after heat exchange is below 160 degrees Celsius before it enters the air cooler, additional water injection points should be added at the inlet of the heat exchanger.
The location of the water injection points depends mainly on the temperature at which the ammonium salts crystallize. After heat exchange with the feed oil, the resulting oil enters the air cooler; generally, demineralized water is injected before it reaches the air cooler. If the temperature of the oil after heat exchange is below 160 degrees Celsius before it enters the air cooler, additional water injection points should be added at the inlet of the heat exchanger. The water injection volume mainly depends on the S and N contents of the raw material.