China Petroleum Chemical Corporation

Sinopec Engineering Incorporation

Beijing Research Institute of Chemical Industry, China Petroleum & Chemical Corporation

Nanjing Industrial Furnace Institute of Tianhua of Chemical Machinery & Automation

Sinopac Engineering Incorporation

China Petroleum & Chemical Corporation, Beijing Institute of Chemical Industry

Changli Li

Yuping Guo

Xiou He

Jingkun Liu

Hainü Shen

Chen Shao

Guoqing Wang

Guang Cheng Li

Zhaobin Zhang

Lijun Zhang

Cong Zhou

Yonghua Zhao

Jinke Li

Mujun Yuan

An ethylene cracking furnace is provided. The ethylene cracking furnace includes at least one radiant section. The at least one radiant section includes bottom burners and/or sidewall burners, and at least one radiant coil arranged in the radiant section. The radiant coil includes at least an upstream pass tube and a downstream pass tube, the upstream pass tube being configured as an inner tube, and the downstream pass tube being configured as an outer tube surrounding the inner tube and having a closed end. The inner tube defines an inner space forming an upstream flow path. A gap defined between the inner tube and the outer tube forms an downstream flow path.

Ethylene cracking furnace

The present disclosure provides an ethylene cracking furnace, comprising at least one radiant section provided with a bottom burner and/or a side burner, and at least one set of radiant coil arranged along a longitudinal direction of the radiant section. The radiant coil is an at least two-pass coil having an N&#x2212;1 structure, wherein N is preferably a natural number from 2 to 8. A manifold is arranged at an inlet end of a downstream tube of said at least two-pass coil, and an outlet end of each upstream tube of said at least two-pass coil is connected to the manifold through a curved connector. The arrangement according to the present disclosure can effectively reduce the expansion differences between the upstream tubes and the downstream tubes, and therefore reduce the stress caused thereby. Consequently, bending of the radiant coil can be avoided, thereby extending the service life of the radiant coil.

An ethylene cracking furnace comprising a high pressure steam drum (), a convection section (), a radiant section (), multiple groups of radiant coils () arranged vertically in the firebox of radiant section, burners () and transfer line exchangers (), each radiant coil comprising a first-pass tube (), a second-pass tube () and a connection member (); feedstocks being introduced into an inlet end of the first-pass tube and outflow from an outlet end of the second-pass tube, said first-pass tube () and said second-pass tube () are non-split coils, and the centerlines of the respective radiant tubes () are within a common plane; said connection member () is a tridimensional structural member comprising an inlet bending tube (), a return bending tube () and an outlet bending tube (); said inlet bending tubes () and said outlet bending tubes () are arranged at two sides of the plane containing the centerlines of said first-pass tubes () and said second-pass tubes (), respectively; the projections of the respective connection members () in a side view are the same curve line that is symmetrical, continuous and closed; the inner diameters of said radiant coils () is varied at least once along the length of the tubes.

The invention relates to an ethylene cracking furnace having a multi-pass radiant coil, comprising at least one radiant section. In the radiant section there are provided with bottom burners and/or sidewall burners, and at least one set of multi-pass radiant coil longitudinally arranged in the radiant section. The multi-pass radiant coil is a four- to ten-pass type radiant coil. At least one tube of the multi-pass radiant coil is arranged to be spatially adjacent to a tube which is not consecutive to said at least one tube. With this arrangement, the thermal radiation influence between tubes with high temperature can be reduced, so that the tubes with low temperature can absorb the radiation heat from the tubes with high temperature. Therefore, the surface temperature of the tubes with high temperature can be reduced, thus extending the lifetime of the radiant coil and the operational cycle of the cracking furnace.

Ethylene cracking furnace with multi-pass radiant coil

Growing community of inventors

Beijing, China

Changli Li