Abstract: The provided is a process for separating by absorption the pyrolysis gas from preparation of lower carbon olefins, wherein a primary absorbent and a secondary absorbent are introduced into the demethanizer to separate by absorption the feedstock of the demethanizer through countercurrent contact therewith at a moderate temperature and pressure, thereby to obtain a top fraction primarily comprising hydrogen and methane and a bottom fraction primarily comprising the absorbents and C2+ fraction, wherein the primary absorbent essentially is a mixed Cn or Cn+ fraction, the secondary absorbent essentially is a Cn? alkane fraction or mixed Cn? or Cn?+ fraction, and wherein n and n? are independently 3, 4 or 5 with the proviso when the secondary absorbent is a mixed fraction, n? is not 3.

Abstract: The present invention provides a fluidized bed reactor and its use for producing olefins from oxygenates, the fluidized bed reactor comprises: a reaction zone located in the lower portion of the fluidized bed reactor and comprising a lower dense phase zone and an upper riser, wherein the dense phase zone and the riser are connected with each other transitionally; a separation zone located in the upper portion of the fluidized bed reactor and comprising a settling chamber, a fast gas-solid separation means, a cyclone and a gas collecting chamber, wherein the riser extends upwardly into the separation zone and is connected at its outlet with the inlet of the fast gas-solid separation means, the fast gas-solid separation means is connected at its outlet with the inlet of the cyclone via a fast gas passage, the cyclone is connected at its outlet with the gas collecting chamber, and the gas collecting chamber is located below the reactor outlet and connected therewith; and a catalyst recycle line for recycling the

Abstract: The provided is a process for separating by absorption the pyrolysis gas from preparation of lower carbon olefins, wherein a primary absorbent and a secondary absorbent are introduced into the demethanizer to separate by absorption the feedstock of the demethanizer through countercurrent contact therewith at a moderate temperature and pressure, thereby to obtain a top fraction primarily comprising hydrogen and methane and a bottom fraction primarily comprising the absorbents and C2+ fraction, wherein the primary absorbent essentially is a mixed Cn or Cn+ fraction, the secondary absorbent essentially is a Cn? alkane fraction or mixed Cn? or Cn?+ fraction, and wherein n and n? are independently 3, 4 or 5 with the proviso when the secondary absorbent is a mixed fraction, n? is not 3.

Abstract: The present invention provides a fluidized bed reactor and its use for producing olefins from oxygenates, the fluidized bed reactor comprises: a reaction zone located in the lower portion of the fluidized bed reactor and comprising a lower dense phase zone and an upper riser, wherein the dense phase zone and the riser are connected with each other transitionally; a separation zone located in the upper portion of the fluidized bed reactor and comprising a settling chamber, a fast gas-solid separation means, a cyclone and a gas collecting chamber, wherein the riser extends upwardly into the separation zone and is connected at its outlet with the inlet of the fast gas-solid separation means, the fast gas-solid separation means is connected at its outlet with the inlet of the cyclone via a fast gas passage, the cyclone is connected at its outlet with the gas collecting chamber, and the gas collecting chamber is located below the reactor outlet and connected therewith; and a catalyst recycle line for recycling the

Abstract: Disclosed is a process for producing light olefins from methanol or dimethyl ether. In the process, the fresh catalyst or the regenerated catalyst is pretreated to deposit a certain amount of coke onto its interior pore surface in advance, to reduce the generation of alkane and heavy olefins, so as to increase the selectivities to ethylene and propylene; and during the production of the light olefins, the pretreated catalyst is used for catalyzing the methanol or the dimethyl ether to produce light olefins. The process can achieve higher yields of ethylene and propylene.

Abstract: A Multiservice Access Concentrator (MAC) provides traffic shaping by allocating at least one cell stream to at least one cell slot of a cell scheduling table. A cell slot and a corresponding cell stream are designated in response to a cell interrupt signal generated following cell transmission. At least one counter and at least one credit buffer are maintained, and a service class of the designated cell stream is determined. The size of the credit buffer is determined by a maximum burst cell size (MBC) of the corresponding cell stream and virtual circuit (VC). A cell of the designated cell stream is transmitted in response to the determined service class and a count of the at least one counter and contents of the at least one credit buffer. Therefore, cells are transmitted based on cell credits. A virtual circuit (VC) builds cell credit based on the sustained cell rate (SCR) of the VC. Cell credit is consumed as cells are transmitted.

Abstract: Disclosed is a catalytic promoter for fluid catalytic cracking of hydrocarbons, comprising a HZSM-5 zeolite in an amount of 5-65 wt % based on the total weight of the catalytic promoter, said zeolite being modified with Zn and at least one element selected from the group consisting of P, Ga, Al, Ni and rare earth elements, the combined amount of said modifying elements being 0.01-10.37 wt % based on total weight of said modified HZSM-5 zeolite. A reduced olefin content in gasoline from catalytic cracking process, an increased gasoline octane number and an increased lower olefin yield can be obtained using said catalytic promoter.

Abstract: A Multiservice Access Concentrator (MAC) provides traffic shaping by allocating at least one cell stream to at least one cell slot of a cell scheduling table. A cell slot and a corresponding cell stream are designated in response to a cell interrupt signal generated following cell transmission. At least one counter and at least one credit buffer are maintained, and a service class of the designated cell stream is determined. The size of the credit buffer is determined by a maximum burst cell size (MBC) of the corresponding cell stream and virtual circuit (VC). A cell of the designated cell stream is transmitted in response to the determined service class and a count of the at least one counter and contents of the at least one credit buffer. Therefore, cells are transmitted based on cell credits. A virtual circuit (VC) builds cell credit based on the sustained cell rate (SCR) of the VC. Cell credit is consumed as cells are transmitted.

Abstract: Disclosed is a catalytic promoter for fluid catalytic cracking of hydrocarbons, comprising a HZSM-5 zeolite in an amount of 5-65 wt % based on the total weight of the catalytic promoter, said zeolite being modified with Zn and at least one element selected from the group consisting of P, Ga, Al, Ni and rare earth elements, the combined amount of said modifying elements being 0.01-10.37 wt % based on total weight of said modified HZSM-5 zeolite. A reduced olefin content in gasoline from catalytic cracking process, an increased gasoline octane number and an increased lower olefin yield can be obtained using said catalytic promoter.