In an embodiment, a reactor for carrying out a melt transesterification reaction at a reactor temperature of 160 to 300° C. and a reactor pressure of 5 to 200 mbar, comprises a cylindrical tank comprising a top, a side, and a bottom, wherein the bottom is convex, extending away from the top; a stirring shaft disposed within the cylindrical tank along an axis thereof so that it is rotatable from outside of the cylindrical tank; a stirring blade extending from the stirring shaft in the cylindrical tank; a reactant solution inlet located on the bottom; and a reaction solution outlet located on the bottom. The reactor can be used for the polymerization of a polycarbonate oligomer.

The invention relates to a new biological fluidized bed process with high concentration powder carriers used for the treatment of municipal wastewater, which is a fluidized bed system based on the principle of sewage biochemical treatment, by adding a compound powder carrier to the biochemical tank, and forming a high concentration mixture after mixing and microbial attachment; the sludge mixture after the reaction is concentrated and separated, and then enters the compound powder carrier cyclone separation and recovery system, which can separate most of the compound powder carrier from the discharged excess sludge, and then return to the biochemical tank for recycling. The highly integrated municipal wastewater treatment process proposed in the invention has high treatment efficiency, small occupation area, low operation energy consumption, and can realize the doubling of sewage treatment capacity and the improvement of effluent water quality without adding additional occupancy.

A reactor system includes a support housing having an interior surface bounding a chamber, the chamber having a vertically extending central longitudinal axis. A flexible bag is disposed within the chamber of the support housing and has an interior surface bounding a compartment. A mixing element is disposed within the compartment of the flexible bag. A drive element, such as a drive shaft, is secured the mixing element, wherein the mixing element is laterally offset from and/or is angled relative to the vertically extending central longitudinal axis of the support housing.

A reactor system includes a support housing having an interior surface bounding a chamber, the chamber having a vertically extending central longitudinal axis. A flexible bag is disposed within the chamber of the support housing and has an interior surface bounding a compartment. A mixing element is disposed within the compartment of the flexible bag. A drive element, such as a drive shaft, is secured the mixing element, wherein the mixing element is laterally offset from and/or is angled relative to the vertically extending central longitudinal axis of the support housing.

Described herein is a method and a system for dispersing particles in a fluid. The method includes stirring a fluid including particles in a stirring container using stirring means. During stirring the fluid is recirculated by continuously retrieving an amount of fluid from a retrieving position. Further, the particles are milled, where during each pass through the milling means a size of particles in the retrieved fluid is reduced. The retrieved fluid having passed through the milling means is continuously reintroduced into the stirring container at a reintroduction position. The reintroduced fluid is mixed with the fluid in the stirring container in a mixing region defined by the stirring means, and the retrieving position is determined such that the retrieved fluid includes particles with an average particle size differing from the average particle size of particles in the mixing region.

Described herein is a method and a system for dispersing particles in a fluid. The method includes stirring a fluid including particles in a stirring container using stirring means. During stirring the fluid is recirculated by continuously retrieving an amount of fluid from a retrieving position. Further, the particles are milled, where during each pass through the milling means a size of particles in the retrieved fluid is reduced. The retrieved fluid having passed through the milling means is continuously reintroduced into the stirring container at a reintroduction position. The reintroduced fluid is mixed with the fluid in the stirring container in a mixing region defined by the stirring means, and the retrieving position is determined such that the retrieved fluid includes particles with an average particle size differing from the average particle size of particles in the mixing region.

Presented and described herein is a stroke system (1) for dosing a fluid from a container (3), comprising a piston pump (5) with a piston (7), so that a fluid can be dosed from a container (3) by displacement of the piston (7), and a temperature control device (29) for controlling the temperature of the fluid to be dosed by means of the stroke system (1).

Disclosed is direct ink write (DIW) print extrusion head for 3D printing of viscous elastomers. The disclosed print extrusion head comprises a mixer assembly, comprising a fluid distribution cap coupled to a carrier, an in-line mixer coupled to the fluid distribution cap. A cooling jacket surrounds the in-line mixer. A nozzle is coupled to the in-line mixer and protrudes below the cooling jacket over a work surface. The position of the nozzle relative to the work surface is changeable. At least one heat source is on the chassis and disposed adjacent to the fluid distribution cap. The at least one heat source comprises a heat guiding element to direct heat to a region onto the work surface below the nozzle.

Disclosed is direct ink write (DIW) print extrusion head for 3D printing of viscous elastomers. The disclosed print extrusion head comprises a mixer assembly, comprising a fluid distribution cap coupled to a carrier, an in-line mixer coupled to the fluid distribution cap. A cooling jacket surrounds the in-line mixer. A nozzle is coupled to the in-line mixer and protrudes below the cooling jacket over a work surface. The position of the nozzle relative to the work surface is changeable. At least one heat source is on the chassis and disposed adjacent to the fluid distribution cap. The at least one heat source comprises a heat guiding element to direct heat to a region onto the work surface below the nozzle.

An expanded particle producing apparatus includes a vessel and a blade stirrer that is located inside the vessel. The blade stirrer comprises a stirrer base and an impeller blade that is attached to the stirrer base. A distance from the bottom of the vessel to the center of the stirrer base (L1) and a depth of the vessel (L2) have a ratio (L1/L2) of 0.01 to 0.2. L1 is measured in a depth direction parallel to L2, and a central axis of the blade stirrer coincides with a central axis of the vessel. The apparatus is configured to produce expanded particles.