A method of carrying out direct thermal decomposition of a hydrocarbon compound into carbon and hydrogen comprises: introducing a gaseous feed stream comprising at least one hydrocarbon compound into a reactor; and removing at least hydrogen gas and particulate carbon formed by thermal decomposition from the reactor. The method includes providing in the reactor a layer permeable to the particulate carbon and comprising loose particles other than the particulate carbon in a gas phase and passing the gaseous feed stream through the layer. The loose particles other than the particulate carbon comprise particles comprising a catalyst on a carrier. The method includes removing at least part of the layer from the reactor, separating constituents of the removed part, the constituents including some of the particles comprising a catalyst on a carrier, and returning the separated particles comprising a catalyst on a carrier to the layer.

Methods of reducing heat exchanger fouling rate or of producing polyolefins may include providing a first gas stream comprising a gas and entrained fine polyolefin particles to a gas outlet line; removing a portion of the entrained fine polyolefin particles from the gas outlet line to form a bypass stream; and providing the bypass stream to a bypass line comprising a bypass line inlet and a bypass line outlet. The bypass line inlet and outlet are located upstream and downstream of a first heat exchanger. The methods may further include providing at least a portion of the first gas stream to the first heat exchanger; and combining the bypass stream and a second gas stream at the bypass line outlet to form a combined gas stream comprising one or more olefins or paraffins. A temperature of the combined gas stream is below the dew point of the combined gas stream.

Processes and apparatuses for alkylating aromatic hydrocarbons with an alkylating reagent to produce an alkylated aromatic product are described. The processes and apparatuses use a riser reactor operated at a superficial velocity of 10 m/s to 25 m/s to produce the alkylated aromatic product. In some embodiments, a combination of steam and aromatic hydrocarbon is used to lift the catalyst.

A fluid catalytic cracking (FCC) process for cracking multiple feedstocks in a FCC apparatus comprising a first set of feed distributors having first distributor tips and a second set of feed distributors having second distributor tips is provided. A first feed is injected into the riser from first distributor tips. A second feed is injected into the riser from second distributor tips. The first distributor tips and the second distributor tips are positioned at different radii in the riser. The first feed and the second feed are cracked in the riser in the presence of an FCC catalyst to provide a cracked effluent stream. The first distributor tips and the second distributor tips are located into a region of lower catalyst density and a region of higher catalyst density respectively in the riser.

A method of producing a composite product is provided. The method includes providing a fluidized bed of metal oxide particles in a fluidized bed reactor, providing a catalyst or catalyst precursor in the fluidized bed reactor, providing a carbon source in the fluidized bed reactor for growing carbon nanotubes, growing carbon nanotubes in a carbon nanotube growth zone of the fluidized bed reactor, and collecting a composite product comprising metal oxide particles and carbon nanotubes.

Apparatus and processes herein provide for converting hydrocarbon feeds to light olefins and other hydrocarbons. The processes and apparatus include, in some embodiments, feeding a hydrocarbon, a first catalyst and a second catalyst to a reactor, wherein the first catalyst has a smaller average particle size and is less dense than the second catalyst. A first portion of the second catalyst may be recovered as a bottoms product from the reactor, and a cracked hydrocarbon effluent, a second portion of the second catalyst, and the first catalyst may be recovered as an overhead product from the reactor. The second portion of the second catalyst may be separated from the overhead product, providing a first stream comprising the first catalyst and the hydrocarbon effluent and a second stream comprising the separated second catalyst, allowing return of the separated second catalyst in the second stream to the reactor.

Systems and methods of reducing heat exchanger fouling rate and of producing polyolefins are provide herein. In some aspects, the methods include providing a first gas stream comprising a gas and entrained fine polyolefin particles to a gas outlet line; preferentially removing a portion of the entrained fine polyolefin particles from the gas outlet line to form a bypass stream comprising a higher concentration of the entrained fine polyolefin particles than is present in the first gas stream; providing the bypass stream to a bypass line comprising a bypass line inlet and a bypass line outlet, wherein the bypass line inlet is located upstream of a first heat exchanger, and wherein the bypass line outlet is located downstream of the first heat exchanger; providing at least a portion of the first gas stream to the first heat exchanger, which produces a first cooled gas stream; and combining the bypass stream and a second gas stream at the bypass line outlet to form a combined gas stream comprising one or more olefins or paraffins, wherein a temperature of the combined gas stream is below the dew point of the combined gas stream.

Systems and methods of reducing heat exchanger fouling rate and of producing polyolefins are provide herein. In some aspects, the methods include providing a first gas stream comprising a gas and entrained fine polyolefin particles to a gas outlet line; preferentially removing a portion of the entrained fine polyolefin particles from the gas outlet line to form a bypass stream comprising a higher concentration of the entrained fine polyolefin particles than is present in the first gas stream; providing the bypass stream to a bypass line comprising a bypass line inlet and a bypass line outlet, wherein the bypass line inlet is located upstream of a first heat exchanger, and wherein the bypass line outlet is located downstream of the first heat exchanger; providing at least a portion of the first gas stream to the first heat exchanger, which produces a first cooled gas stream; and combining the bypass stream and a second gas stream at the bypass line outlet to form a combined gas stream comprising one or more olefins or paraffins, wherein a temperature of the combined gas stream is below the dew point of the combined gas stream.

A feed injector may have a body having an outer wall and an inner wall with a first conduit formed between the outer wall and the inner wall. The first conduit is configured to receive a atomizing gas. Additionally, a second conduit may be formed by the inner wall, and the second conduit is configured to receive a liquid. The first conduit and the second conduit are separated by the inner wall. Further, a mixing chamber may be provided at an outlet of the first conduit and an outlet of the second conduit. The atomizing gas from the first conduit and the liquid from the second conduit hit and/or mix together in the mixing chamber to form liquid droplets and a mixture of the atomizing gas and the liquid. Furthermore, a flow cone may have a first end in the second conduit and a second end in the mixing chamber.

This present disclosure relates to apparatuses for methylation of aromatics in an aromatics complex for producing a xylene isomer product. More specifically, the present disclosure relates to the use of riser slip reduction technology to improve the methanol feed and catalyst contacting which will improve the product yield rate.