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.

Disclosed are a catalyst pre-hydrocarbon-pooling method and a pre-hydrocarbon-pooling device, relating to the technical field of preparation of low carbon olefins. A regenerated catalyst enters a pre-hydrocarbon-pooling reactor, and a pre-hydrocarbon-pooling reaction occurs between the regenerated catalyst and an activation medium to form “hydrocarbon pool” active species. “Pre-hydrocarbon-pooling” treatment is performed on the regenerated catalyst by providing a pre-hydrocarbon-pooling device, so that the regenerated catalyst forms the “hydrocarbon pooled” active species and carbon deposition before entering into an oxygenate conversion reactor, by way of which “hydrocarbon pool” active species distribution and coke distribution of the catalyst in the conversion reactor are improved. This shortens or eliminates a reaction “induction period” and improves the catalytic activity and selectivity of the regenerated catalyst for a reaction of an oxygenate to low-carbon olefins.

A photoreactor having computer actuated input/output ports is operated by introducing reactant through an input port and collecting product through an output port, and upon closure of the input and output ports, treating photocatalyst within the photoreactor to remove intermediates limiting performance of the photocatalyst. Once the photocatalyst is regenerated, introduction of reactant to the photoreactor through the input port and collection of product from the output port can be resumed. The automated process does not require removal of catalyst from the photoreactor and significantly improves process economics.

The present disclosure provides systems and methods for processing ammonia. The system may comprise one or more reactor modules configured to generate hydrogen from a source material comprising ammonia. The hydrogen generated by the one or more reactor modules may be used to provide additional heating of the reactor modules (e.g., via combustion of the hydrogen), or may be provided to one or more fuel cells for the generation of electrical energy.

Techniques regarding the polymerization of polyurethanes are provided. For example, one or more embodiments described herein can comprise synthesizing, via a polymerization reaction performed within a flow reactor, a polyurethane. The polymerization reaction can polymerize a diol with a diisocyanate.

A method for starting a slurry bubble column reactor that includes a reactor vessel holding a settled or slumped bed of particles and a liquid phase from which the particles have settled includes introducing a flow of a re-suspension liquid into the settled or slumped bed to loosen the settled or slumped bed. The introduction of the re-suspension liquid takes place before the introduction of any gas into the settled or slumped bed, or together with feeding of gas into the settled or slumped bed, provided that, if gas is fed together with the re-suspension liquid into the settled or slumped bed before the settled or slumped bed has been loosened, the gas has a superficial gas velocity in the reactor below 10 cm/s. Once the settled or slumped bed has been loosened by at least the re-suspension liquid, gas is passed at a superficial gas velocity above 10 cm/s through the liquid phase.

An advanced regulatory controller for a converter of a catalytic olefins unit is disclosed. A Fluid Catalytic Cracking (FCC) type converter (i.e., reactor-regenerator) is combined with an ethylene style cold-end for product recovery. The regulatory controller operates using an Advanced Regulatory Control (ARC) application using variables, such as a controlled variable, four disturbance variables, associated variable, and a manipulated variable. The ARC application manipulates fuel oil or tail gas flow to a regenerator in response to an expected future steady state value of a regenerator bed temperature resulting from changes in the values of a selected set of the variables.

A fluidizing nozzle for introducing fluid into a fluidized bed reactor and a fluidized bed reactor. The fluidizing nozzle includes a nozzle tube limiting at least a part of a feed channel in which fluid is configured to flow, at least one fluid discharge opening arranged near a downstream end of the nozzle tube, and a pot-like hood, which sealingly closes the nozzle tube with a hood cover of the pot-like hood at the downstream end of the nozzle tube at which said at least one fluid discharge opening is provided. The feed channel is provided with a flow restriction element defining at least one flow restriction feed channel upstream of said at least one fluid discharge opening.

A system and method for producing dimethyl ether (DME) via dry reforming and DME synthesis in the same vessel, including converting methane and carbon dioxide in the vessel into syngas (including hydrogen and carbon monoxide) via dry reforming in the vessel, cooling the syngas via a heat exchanger in the vessel, and synthesizing DME from the syngas in the vessel.

An actuator is provided that includes a housing, a linear actuating shaft disposed within the housing, a piston coupled with the shaft, and a fluid barrier disposed on an end of the shaft and encircled by the piston. The piston is movable longitudinally between an extended configuration and a retracted configuration upon rotation of the shaft. The fluid barrier engages an inner surface of the piston preventing fluid communication across the fluid barrier. The fluid barrier has a shaft engaging side which receives the shaft and a fluid facing side. A cavity is formed between the piston and the fluid facing side and expands when the piston moves to the extended configuration and contracts when the piston moves to the retracted configuration. A port is disposed in the piston and extends from the cavity to external the piston thereby permitting fluid communication between the cavity and external the piston.