A process and device for reducing coke powder of delayed coking fractionation tower

Abstract

The invention provides a process and device for reducing the coke powder of the delayed coking fractionation tower. Before the reaction oil gas enters the fractionation tower, an oil gas wax oil heat exchange nozzle, an oil gas circulation oil washing nozzle, a gas-liquid separation distributor, and a gas-liquid separation tank are installed. , cyclone dehydrator, etc., the reaction oil gas is cooled, washed, coke powder capture, gas-liquid separation, deliquoring and decoking powder and other processes, so that most of the coke powder carried in the reaction oil gas is washed to the liquid phase circulating oil In the process, the coke powder in the circulating oil is removed through the filter, thereby reducing the coke powder content of the reaction oil gas entering the fractionation tower. By reducing the amount of oil and gas entering the fractionating tower and lowering the temperature of the oil and gas, the linear velocity of the oil and gas in the lower part of the fractionating tower is reduced. By saving the heat exchange plate in the lower part of the fractionating tower for adjusting the circulation ratio, the coke powder settlement space in the oil and gas is increased. By setting wax The under-oil backflow spray distributor supplements and washes oil and gas, further reducing the coke powder content in the side line of the fractionation tower and the top product. The invention can effectively reduce the amount of coke powder entering the fractionation tower with oil and gas and reduce the amount of coke powder entering sideline products with oil and gas, thereby improving the product quality of the delayed coking device, prolonging the operating cycle of the delayed coking device and downstream devices, and saving operating costs.

Description

technical field [0001] The invention relates to a delayed coking technology in the field of petroleum refining, in particular to a process and a device for reducing coke powder of a delayed coking fractionation tower. Background technique [0002] Delayed coking process is an important low-quality heavy oil processing technology. Residual oil or heavy oil similar to residual oil, dirty oil, fuel oil, and crude oil are used as raw materials, which are quickly heated to a certain temperature (about 500°C) by a heating furnace and then enter coke The tower is a process in which a series of reactions such as cracking and condensation occur under suitable temperature and pressure conditions in the tower to generate gas, naphtha, diesel oil, wax oil, cycle oil components and coke. As a process of continuous production and discontinuous operation, there are generally at least two coke towers. When one coke tower is on-line coke generation, the other coke tower performs coke removal...

AI Technical Summary

Problems solved by technology

The main hazards of coke powder entering the fractionation tower with oil and gas are: (1) causing coking and clogging of the C tray of the coking fractionation tower, affecting the fractionation effect and product quality; resulting in an increase in the pressure drop of the tray, reducing the processing capacity of the device, and shortening the operating cycle of the device (2) cause coke powder to be carried in each side line product of the fractionating tower, coker gasoline and diesel oil are usually used as products or raw materials for downstream devices after hydrotreating, coker wax oil is usually used as raw materials for catalytic devices through hydrotreating, coker gasoline 3, Diesel oil 4 and wax oil 5 carry coke powder, pollute the catalyst of the hydrogenation reactor, affect the service time of the catalyst, and then affect the operation cycle of the hydrogenation unit, increasing production costs

(3) Coking rich gas 2 carries coke powder, one is to block the absorption tower, desulfurization tower tray or packing of the rich gas treatment system, and the other is to pollute the desulfurization agent of dry gas and liquefied gas desulfurization, which affects the desulfurization effect and increases the operation cost

(4) Increase the coke powder in the circulating oil, and the coke powder will fall into the bottom of the tower with the circulating oil, causing a large amount of coke powder to accumulate at the bottom of the fractionation tower, causing coking at the bottom of the tower, and even blocking the outlet at the bottom of the tower, causing the device to be forced to shut down; fractionation The coking oil at the bottom of the tower is used as the feed material of the heating furnace, and the coke powder content is high, which will accelerate the coking speed of the heating furnace tube and affect the operation cycle of the delayed coking unit

[0012] In short, coking high-temperature oil and gas carry a large amount of coke powder into the coking fractionation tower, which will not only affect the stable operation and product quality of the coking unit, but also affect the stable and long-term operation of the downstream processing equipment

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