A delayed coking method

Abstract

The present invention relates to a coking delaying method, which comprises that a coking delaying raw material heated by a heating furnace radiation section is injected into a coke tower to react, the oil-gas produced from the reaction is subjected to cyclone separation, and the separated purified oil-gas is subjected to fractionation to obtain the coked distillate oil, wherein during the reaction process, cooling oil and / or cooling water is injected into the top portion of the coke tower through a pipeline, the pipeline for injecting the cooling oil and / or cooling water extends into the coke tower, and the length of the pipeline extending into the coke tower is 8-45% of the diameter of the coke tower, and during the cyclone separation process, the coked distillate oil and / or the additionally added distillate oil having the characteristic similar to the characteristics of the coked distillate oil is adopted as the washing oil, and the bottom oil separated in the cyclone separation process is adopted as the coking delaying raw material to return to the coke tower so as to react. With the coking delaying method of the present invention, the liquid yield can be improved, the coked wax oil quality can be improved, and the stable operation period of the single tower can be prolonged.

Description

technical field [0001] The invention relates to a delayed coking method. Background technique [0002] In recent years, due to the trend of crude oil becoming inferior and heavy, delayed coking has become one of the main processes for processing heavy oil in today's refineries due to its strong adaptability of raw materials and obvious economic benefits. Delayed coking is a thermal processing process of deep thermal cracking, which can convert heavy oil into dry gas, liquefied gas, coker gasoline, coker diesel, coker wax oil and coke and other products. Usually, the sum of the yields of coked gasoline, coked diesel oil and coked wax oil is taken as the liquid yield of delayed coking, and the liquid yield is the most important technical and economic index of the coking process. Currently, the most common delayed coking processes in industry include conventional processes and operating processes that can flexibly adjust the cycle ratio. The process of conventional delayed co...

AI Technical Summary

Problems solved by technology

Due to the high gas velocity during normal production of the coke tower, and some drop-shaped raw materials are easily carried directly to the large oil and gas pipeline without sufficient reaction. Long-term operation will cause coking and increase the top pressure of the coke tower, which is not conducive to improving liquid recovery.

On the other hand, after the distributor has been used for a period of time, a small amount of coke will be generated on the surface of the distributor, which will affect the effect of the distributor. If it is blocked, it will also bring certain operational risks; The operation of defocusing becomes complicated

[0006] CN102220166A discloses a delayed coking method for feeding materials on the coke tower. Fresh raw materials enter the coke tower from the top or side of the coke tower after being heated by the radiation section of the heating furnace. Blowing a certain amount of gaseous medium into the bottom of the coke tower is similar to the analysis of CN102220165A. Some drop-shaped raw materials are likely to cause coking in large oil and gas pipelines, which is not conducive to improving liquid recovery; coke generated on the surface of the distributor will affect the effect of the distributor. If Blockage will also bring certain operational risks; in addition, since the distributor extends from the cylinder into the tower, it will affect the operation of hydraulic decoking

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