This invention relates to a self cleaning reactor and to a process for the oligomerization of ethylene that employs a self-cleaning reactor. The reactor includes a mass of inert, particulate cleaning bodies that are entrained by the liquid in the reactor and scour the internal surfaces of the reactor during normal operation. This scouring action reduces the level of fouling on the reactor surfaces. Foulant material (polyethylene) is removed from the process on a continuous basis but the cleaning bodies remain within the reactor.

A device for the descending flow of a hydrocarbon-containing liquid containing solid particles at the bottom of an item of equipment (1) and a process for the conversion of hydrocarbon-containing feedstocks implementing said device.

Provided is an apparatus for preparing oligomer including: a reactor for carrying out oligomerization reaction by supplying a monomer stream and a solvent stream; and line 1 and line 2 which are separately provided in a lower side of the reactor, wherein line 1 includes a first level control valve and line 2 includes a second level control valve, and the reactor is periodically alternately operated in first operation mode and second operation mode, thereby switching a pipe through which the product is discharged, so that a plugging phenomenon of the pipe through which the product is discharged and the valve can be prevented.

A liquid process assembly, the assembly including a length of pipework, and a reversible pump for selectively reciprocally moving liquid through the pipework.

A stripper for stripping a urea/carbamate mixture. The stripper comprises a shell and a plurality of tubes disposed within the shell. A shell-side space is provided between the tubes and the shell. A first heating fluid inlet, a second heating fluid inlet, and a heating fluid outlet are in fluid connection with the shell-side space. The second heating fluid inlet is disposed between the first heating fluid inlet and the heating fluid outlet. Related uses, systems, and methods are provided as well.

The present disclosure relates to an apparatus for preparing an oligomer, and more particularly, to an apparatus for preparing an oligomer including: a reactor including a gaseous area having a first gaseous reactant inlet provided at a lower portion thereof, and a reaction area in which a reaction medium reacts with the gaseous reactant above the gaseous area; a second gaseous reactant inlet provided on an inner wall of the reactor in the gaseous area and a third gaseous reactant inlet provided on an inner wall of the reactor facing the second gaseous reactant inlet; and a first injection nozzle connected to the second gaseous reactant inlet and a second injection nozzle connected to the third gaseous reactant inlet.

An aspect ratio flow metering device may comprise a concentrate inlet portion, one or more restricted flow portions of tubing fluidly connected to the concentrate inlet portion, and a metered concentrate outlet portion fluidly connected to the one or more restricted flow portion of tubing. The narrowest part of the one or more restricted flow portions of tubing may each have a length (R.sub.L): inner diameter (R.sub.ID) ratio of at least 10:1. The metered concentrate outlet portion may have an inner diameter (O.sub.ID) greater than R.sub.ID. The concentrate inlet portion may have an inner diameter (I.sub.ID) greater than R.sub.ID. The aspect ratio flow metering device may be structurally configured to limit flow of a concentrate into a hydrodynamic mixing apparatus. Also disclosed are methods for using the aspect ratio flow metering device to mix fluids.

The present invention relates to a plant for oligomerizing ethylene to produce oligomerized alpha-olefins, with production of a fouling by-product in the form of a deposit, said plant comprising a reaction section comprising: —a reactor (c) for two-phase gas/liquid or single-phase all-liquid oligomerization proceeding from an optional solvent, an oligomerization catalyst and ethylene, and —cooling means associated with said reactor in the form of at least one cooling circuit external to the reactor and/or in the form of a jacket of the walls of the reactor. Packings are disposed in the reaction section in order to increase the contact surface area per unit volume that is accessible to the deposition of the byproduct.

An easily polymerizable substance handling device is provided that can prevent generation of irregularities and steps between a pipeline and a cover member due to the cover member being installed at an opening part of the pipeline. A cover part 3 is formed to have a curved surface 3a on a side closer to inside of a pipeline 1. The shape of the surface 3a on the pipeline 1 side is preferably a concave shape when viewed from inside of the pipeline 1. The shape of the surface 3a of the cover part 3 on the pipeline 1 side is more preferably the shape of a curved surface having a curvature radius equal or approximate to that of the internal circumference of the pipeline 1. With this configuration, a polymer material is unlikely to be generated at the cover part 3 and around a gap 1b at an opening part 1a, and the frequency of cleaning can be reduced as compared to conventional cases.

Provided is a method of preparing a diester-based material, more particularly, a method of preparing a diester-based material, which is carried out by a continuous preparation process of a diester-based material including a reaction part in which a total of n reaction units from a first reaction unit to an nth reaction unit are connected in series, the reaction unit including a reactor which esterifies dicarboxylic acid and alcohol, including: esterifying dicarboxylic acid and alcohol in a reactor of the first reaction unit to produce a reaction product, and supplying a lower discharge stream including the reaction product to a reaction unit at a rear end through a lower discharge line; and supplying a liquid material through a liquid supply line connected to a lower discharge line of the reactor of the first reaction unit.