Catalytic fractionation middle section system

Use it when absorption has stabilized and the reboiler is isolated

It is used at the start of operation. At the beginning, Line 1 is filled with diesel; since the fuel injection process occurs gradually, increasing the load step by step, the fractionation system only has oil slurry and cold reflux to establish a circulation. There is no reflux in the top circulation accumulation tank of Line 1, and liquid phase reflux to the extraction tank of Line 1 can occur only when there is contact between the vapor and liquid phases. This process takes some time. In order to shorten the startup period and establish circulation in Line 1 as soon as possible, a large-diameter pipeline is used, allowing heat exchange only within the fractionation unit to ensure stability and reduce the volume of circulation. Circulation is established as early as possible, and during the operation process, water stored in the top circulation of Line 1 is removed promptly to prevent problems at the pump extraction points

Is it a bypass line of the heat exchanger? There is also a three-way control valve on this bypass line, which is used to regulate and stabilize the heat level of gasoline or deethanized gasoline.

It’s obvious that this is a person who understands the situation: without a proper intermediate circulation, the compressor cannot be started; without stability, there can be no feeding. It’s all about following the correct sequence of operations.

That’s correct; at this time, the two bottom reboilers in the absorption system are stabilized using a steam heat source, which ensures that the rich gas produced by the compressor enters the absorption and stabilization system without having to be vented through a flare. The distillation tower can also establish a circulation reflux as early as possible; the next step is to send the intermediate oil to the absorption unit for stabilization and to switch off the steam.

This cross-line has never been used; only diesel is used to supply the middle line, while gasoline is used to supply the top circulation line. It enables rapid establishment of both the top circulation and the middle line circulation during operation

In practice, things work this way, but the design institute designed this line with the aim of establishing a cycle quickly; the idea was good after all

It is this cross-line that plays a crucial role when in use. At the beginning of operation, in order to get the distillation system up and running as quickly as possible, the stabilization system can be bypassed; at that time, the stabilization system can use steam as a heat source.

It must be that your processing volume is very high; generally, diesel is introduced before starting up to replenish the medium, and once the heat exchanger is in use, the production volume increases quickly