Hydrocracking stripping tower
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I would like to ask if your hydrocracking unit’s distillation system employs a design that involves stripping first and then distillation. If so, what are the operating conditions for your stripping towers? For the new unit we are installing, we plan to use low-pressure steam from the system for stripping (at a temperature of 250). Is this acceptable? Is there water in the bottom oil? How is the bottom temperature of your stripping tower regulated? Thank you!
Our unit employs the main stripping tower process; at a steam temperature of 250°C, water is generally not present in the steam. However, a large volume of steam injected may cause water to appear at the bottom of the tower. We use the feed to the stripping tower to control the temperature at the bottom of the tower, and steam is used to control the quality of the vapor extracted from the top of the tower. Our goal is to ensure the quality of the liquefied gas. Some other units use stripping steam to control the temperature at the bottom of the tower, but the principle remains the same: to ensure that the product at the top of the tower meets the required standards. If the conversion rate increases. The feed temperature also increases, and at the same time the content of light components rises; as a result, a large amount of stripping steam is required to lower the temperature at the bottom of the tower
Our unit is also designed with stripping followed by distillation; the heat source is a heating furnace, the top pressure of the tower is set at 0.7 MPa, and the temperature is 50 degrees.
Our plant uses a design that involves stripping first and then distillation. The design pressure of the tower is 0.68 MPa, while the operating pressure is 0.50 MPa. The temperature at the top of the tower is 77°C, and the temperature at the bottom is 202°C. Regarding the issue of water in the tower: there is a low-pressure separator before the stripping tower, which facilitates effective separation of oil from water. The temperature at the bottom of the tower is controlled by regulating the amount of hot steam supplied to it
In hydrocracking, a stripping tower is used first; its main function is to remove hydrogen sulfide. The pressure is 0.75 MP, the top temperature is 115 degrees, and the steam temperature at the bottom of the tower is 380 degrees – it is superheated steam. The distillation tower relies on a heating furnace to provide the necessary temperature, and it also uses stripping steam, which is as well superheated steam.
In our facility, pre-distillation is carried out using superheated steam stripping at a temperature of 380 degrees, with a top pressure of 14.7 Mpa. The use of superheated steam helps to reduce the amount of water contained in the oil products, and it also improves the processing capacity – with very good results
The process of stripping first and then distilling is quite common; temperature and pressure vary depending on the operations involved. The water issue can be resolved in the earlier stages of fractional separation
Our plant uses stripping followed by distillation; there is a low-pressure separator before the stripping tower, so no water ends up in the bottoms of the towers. Operating pressure of the towers: 0.75 MPa. Top temperature of the towers: 120°C. Bottom temperature of the towers: 210°C. The bottom temperature is maintained through superheated steam