Method for treating scorching gas of ethylene cracking furnace

Abstract

The invention belongs to the technical field of scorching gas treatment, and relates to a method for treating scorching gas of an ethylene cracking furnace. The method is carried out in a device for treating the scorching gas of the ethylene cracking furnace, and the device is characterized in that the outlet end of a gas inlet pipeline is communicated with a feeding port of a decoking tank, and a decoking valve is arranged on the gas inlet pipeline; a gas outlet of the decoking tank is communicated with a vent line, and a first valve is arranged on the vent line; and the gas outlet of the decoking tank is communicated with a scorching opening of a hearth of the cracking furnace through a hearth returning pipeline, and a second valve is arranged on the hearth returning pipeline. The method comprises the following steps of S1, opening the decoking valve, enabling the scorching gas to enter the decoking tank, and separating the scorching gas to remove coke particles in the scorching gas; S2, when the cracking furnace is in a baking state, a hot standby state after first-time starting or scorching or an emergency state, opening the first valve, closing the second valve, and discharging decoking gas to the atmosphere; and when the cracking furnace is in a hot standby state in a scorching period or before scorching, closing the first valve, opening the second valve, and returning the decoking gas to the hearth for combustion.

Description

technical field [0001] The invention belongs to the technical field of coke gas treatment, and more specifically relates to a method for treating coke gas of an ethylene cracking furnace. Background technique [0002] As the country and society have higher and higher requirements for environmental protection, the requirements for the exhaust gas discharged into the atmosphere by the petrochemical industry are becoming more and more stringent. [0003] Ethylene is an important chemical raw material. The mainstream process for producing ethylene is high-temperature cracking of hydrocarbon raw materials in a cracking furnace. The resulting cracked gas is quenched by a quenching system and then transported to the downstream processing system through pipelines. In a cracking furnace operation cycle, when hydrocarbons are thermally cracked at high temperature, catalytic coking, free radical coking and condensation coking will occur on the inner surface of the furnace tube in the r...

AI Technical Summary

Problems solved by technology

Not only that, because there are cracked gas and other hydrocarbons remaining in the furnace return pipeline, the residual cracked gas and other hydrocarbons will return to the furnace of the cracking furnace H along with the coke cleaning gas, which may cause the burner at the bottom of the furnace to go out

The inventor also found that the current common practice is to add a cut-off valve in the charring main pipe of the furnace return, but since the distance from the charred pipeline to the charred inlet of the furnace after the valve is relatively long, if the furnace pipeline is not physically cut off before the charred port Measures, then when the furnace is in normal operation or in other states without returning to the furnace, it is easy to form back-mixed gas in the charred pipeline and the furnace, resulting in overheating of the charred pipeline and affecting the combustion of the burner

Images