A system for preventing a catalyst from overheating is provided. The system includes: a first reactor filled with a catalyst at least in part and configured to receive reaction gas and produce product gas; and a second reactor configured to cool a catalyst discharged from the first reactor. The catalyst is circulated between the first reactor and the second reactor by injecting the catalyst cooled in the second reactor into the first rector.

The invention relates to a cyclone (10) for mechanical separation of particles in suspension in a gas, in particular intended for a fluid catalytic cracking unit, said cyclone comprising the following elements:

a separation chamber (101),

an inlet duct (102) that opens into the chamber (101),

a gas outlet duct (103) located in the upper portion of the chamber (101) and

a particle outlet duct (104) located in the lower portion of the chamber (101), characterized in that each element of the cyclone is made of a ceramic material.

The invention also relates to a fluid catalytic cracking unit equipped with at least one cyclone made of ceramic material.

This invention provides a fluidized catalytic cracking apparatus and process for converting a hydrocarbon feedstock containing higher concentrations of Conradson Carbon Residue (CCR), metal impurities, etc into lighter products by employing two riser reactors in which the feed impurities are removed using an adsorbent in a first riser reactor and cracking a portion of first riser reactor liquid product in a second riser reactor to lighter products using the active catalyst thus eliminating the catalyst deactivation due to metal, impurities and FCC catalyst activity dilution effect to achieve a better conversion and higher catalyst longevity.

One exemplary embodiment can be a process for fluid catalytic cracking. The process can include sending a first catalyst from a first riser reactor and a second catalyst from a second riser reactor to a regeneration vessel having a first stage and a second stage. The first catalyst may be sent to the first stage and the second catalyst may be sent to the second stage of the regeneration vessel. Generally, the first stage is positioned above the second stage.

A regeneration method for catalytic cracking reaction, the method is applied in a catalytic reaction process of petroleum hydrocarbon materials, and the method comprises: feeding the regenerated and semi-regenerated catalyst from a regenerator separately into different positions of a reactor for reaction. A part of the semi-regenerated catalyst is firstly processed in a purification cooler for removing carried nitrogen, oxygen, carbon dioxide and impurity gases before being fed into the reactor. Spent catalyst or the purified and cooled semi-regenerated catalyst is fed into a catalyst mixing section of the reactor for controlling the temperature of the catalyst being contact with the oil material to be gasified, thereby achieving a three stage cycle of the catalyst in the reactor and a three stage control for the reaction outlets of the oil material gasification zone and the cracking reaction zone and the catalyst taking part in the reaction.

The invention relates to a method and to a plant for chemical looping oxidation-reduction combustion (CLC) of a gaseous hydrocarbon feed, for example natural gas essentially containing methane. According to the invention, catalytic steam reforming of the feed is performed between two successive feed combustion steps on contact with an oxidation-reduction active mass in form of particles. The reforming catalyst is arranged in a fixed bed in an intermediate reforming zone (130) between the two reduction zones (120, 140) where the two combustion steps are conducted.

FIG. 2 to be published.

A process for producing black powder oxygen carriers for use in a chemical looping combustion unit includes the steps of: (a) removing and collecting the black powder waste material that was formed in a gas pipeline; (b) pre-treating the collected black powder to adjust its spherical shape to avoid attrition and fines production; and (c) activating the black powder to increase its reactivity rate and produce the black powder oxygen carrier that is suitable for use in the chemical looping combustion process as an oxygen carrier.

The method for catalytic methanation of synthesis gas includes the following steps: 1) feeding the synthesis gas into the bottom of a reactor of an upward concurrent flow transporting bed so as to adequately mix and preheat with methanation catalyst entering the bottom of the reactor until the activation temperature of the catalyst is reached and then the methanation reaction begins; and 2) after the methanation reaction, immediately passing the product gas and the catalyst grains outputted from the transporting bed into a gas-solid separator to perform a rapid separation so as to obtain the product gas.

Systems and methods for producing light olefins wherein a feed stream comprising naphtha is flowed into a reaction unit comprising a fast fluidized bed reactor coupled to and in fluid communication with a riser reactor. The fast fluidized bed reactor comprises baffles therein to minimize backmixing therein to maximize the production of light olefins. The effluent from the fast fluidized bed reactor is further flowed to the riser reactor. The lift gas, which can comprise nitrogen, methane, flue gas, or combinations thereof, is injected in the reaction united via a sparger. Effluent of the riser reactor is separated in a product separation unit to produce a product stream comprising light olefins and spent catalyst. Spent catalyst is further stripped by a stripping gas comprising methane, nitrogen, flue gas, or combinations thereof. Stripped spent catalyst is regenerated to produce regenerated catalyst, which is subsequently flowed to the fast fluidized bed reactor.

The present invention relates to the field of high polymer material manufacturing, and discloses an air-isolated continuous feeding system for synthesizing polylactic acid from lactide and a feeding method thereof. The continuous feeding system comprises a raw material bag/box and a raw material collector for collecting and outputting lactide, the raw material bag/box is connected with a shielding gas input pipeline, a discharge pipe is movably inserted into the raw material bag/box, a cyclone separator is connected downstream of the discharge pipe, and a solid substance outlet of the cyclone separator is connected with the raw material collector. According to the invention, deterioration of the lactide raw material incurred by moisture absorption and oxidation is avoided, and the reaction conversion ratio and final product purity are improved. The continuous feeding system is easy to operate, can save manpower and material resources, and is applicable to industrial application.