Feed method for coal tar hydrogenating unit

Abstract

The invention relates to a feed method for coal tar. After the pressure of a coal tar raw material is boosted by a hydrogenation reaction raw material booster pump, the coal tar raw material enters a hydrogenation reactor without any indirect heat exchange; and before the pressure of the coal tar raw material is boosted, the coal tar raw material can be hot stream from a fractionating tower. The method can avoid a high-pressure heat-exchange temperature-rise process of the coal tar, eliminate the problem of fouling of high-pressure coal tar heat exchangers, reduce the hydrogenation catalyst bed pressure drop, slow down the coking, and prolong the operation cycle.

Description

technical field [0001] The invention relates to a method for feeding a hydrocarbon hydrogenation unit that is easily deteriorated by heating; in particular, the invention relates to a method for feeding a coal tar hydrogenation unit; The feeding method of coal tar hydrogenation unit that is coked or easily scaled by heating. Background technique [0002] In the known coal tar hydrogenation device, after the raw material of coal tar at normal temperature or lower temperature is boosted by the hydrogenation reaction raw material pump, it passes through the high-pressure heat exchanger to indirect heat exchange with the hydrogenation reaction effluent to recover heat energy, and then enters the hydrogenation reaction. Reactor, and a variety of coal tar raw materials share the hydrogenation reaction raw material pump. [0003] It is well known that coal tar, especially coal tar containing heavy fractions (such as conventional boiling points higher than 250°C), and more particul...

AI Technical Summary

Problems solved by technology

[0006] ① In the heat exchange process before entering the hydrogenation catalyst bed, the coal tar high-pressure heat exchanger whose coal tar operating temperature is between the metamorphic temperature (such as 200-300°C) has serious fouling on the coal tar side and needs to be cleaned regularly, resulting in unplanned shutdown;

[0007] ②In the heat exchange process before entering the hydrogenation catalyst bed, the coal tar high-pressure heat exchanger whose operating temperature is between the metamorphic temperature (such as 200-300 ℃) will greatly reduce the heat exchange effect due to serious fouling, which will affect the subsequent heat exchange. The heater works normally;

[0010] ①Do not process or less process the scale-prone fraction, but this method reduces resource utilization and is uneconomical;

[0011] ② Coal tar heat exchangers use scale inhibitors, because the scale inhibitors cannot change the chemical properties of coal tar scaling components, the effect is very poor

[0012] There is no report on the feeding method of significantly or completely improving the fouling of high-pressure heat exchangers with coal tar