Abstract: An operation decision-making method for centralized cloud energy storage capable of participating in power grid auxiliary services. The method includes: establishing a model predictive control model; obtaining operating parameters of the current period t from a grid control center at a beginning of a current decision-making cycle; predicting operating parameters within the predetermined time range based on historical data; obtaining decision variables according to the model predictive control model, the operating parameters of the current period and the operating parameters within the predetermined time range; setting a charging power of the centralized energy storage facility in the current period t and a discharging power according to the decision variables; obtaining an actual power of the centralized energy storage facility at an end of the current period t through sensors installed on the centralized energy storage facility as a parameter for a next decision period.

Abstract: Disclosed is a centralized cloud energy storage system for massive and distributed users and a transaction settlement method thereof, a storage medium, and a terminal. The system includes: a centralized energy storage facility invested and operated by a cloud energy storage service provider; the massive and distributed users; and a power network and a user energy management system connecting the centralized energy storage facility with the massive and distributed users. A user sends a charging and discharging request to the cloud energy storage service provider through the user energy management system, and the cloud energy storage service provider issues a charging and discharging instruction to the centralized cloud energy storage system.

Abstract: An operation decision-making method for centralized cloud energy storage capable of participating in power grid auxiliary services. The method includes: establishing a model predictive control model; obtaining operating parameters of the current period t from a grid control center at a beginning of a current decision-making cycle; predicting operating parameters within the predetermined time range based on historical data; obtaining decision variables according to the model predictive control model, the operating parameters of the current period and the operating parameters within the predetermined time range; setting a charging power of the centralized energy storage facility in the current period t and a discharging power according to the decision variables; obtaining an actual power of the centralized energy storage facility at an end of the current period t through sensors installed on the centralized energy storage facility as a parameter for a next decision period.

Abstract: Disclosed is a centralized cloud energy storage system for massive and distributed users and a transaction settlement method thereof, a storage medium, and a terminal. The system includes: a centralized energy storage facility invested and operated by a cloud energy storage service provider; the massive and distributed users; and a power network and a user energy management system connecting the centralized energy storage facility with the massive and distributed users. A user sends a charging and discharging request to the cloud energy storage service provider through the user energy management system, and the cloud energy storage service provider issues a charging and discharging instruction to the centralized cloud energy storage system.

Abstract: 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.

Abstract: 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?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.

Abstract: 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?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.

Abstract: 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?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.

Abstract: 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.

Abstract: 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?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.

Abstract: 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.

Abstract: 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.