The present disclosure relates to a process for preparing polymers using a plug flow reactor. The process includes providing an aqueous monomer solution comprising amide monomers; evaporating the aqueous monomer solution to form a concentrated monomer solution; and polymerizing the concentrated monomer solution in a plug flow reactor comprising a shell side and a tube side to form a first process fluid comprising polymers. The concentrated monomer solution flows on the shell side from the inlet to the outlet.

A reaction chamber for a chemical reactor comprises a casing (100) of the reaction chamber, a floor (200) of the reaction chamber having an opening (300) located in the floor, an agitator shaft (400) located in the chamber and having at least one agitator element (500), connected thereto, wherein the agitator shaft (400), seen in the longitudinal direction, has a beginning (600) and an end (700). In the opening (300) of the floor (200) a removable sleeve (800) is provided, which projects out of the reaction chamber. The sleeve (800) is arranged in alignment with the axis of rotation of the agitator shaft (400). The internal diameter of the sleeve (800) is greater than the diameter of the agitator shaft (400) and the agitator shaft (400), at the beginning (600) thereof and/or at the end (700) thereof, is adapted to absorb reversibly a torque provided by means of a further shaft and/or to transmit a torque to a further shaft. Using such a reaction chamber, it is possible to build up modular chemical reactors having decreased backmixing.

Methods of generating performic acid by contacting aqueous oxidizing agent and aqueous formic acid source in liquid phase are disclosed. A system and apparatus for the in situ production of the performic acid chemistries is further disclosed. In particular, a continuous flow reactor is provided to generate performic acid at variable rates. Methods of employing the oxidizing biocide for various disinfection applications are also disclosed.

A method for producing a polyolefin is provided. The method includes steps of polymerizing an olefin in a first gas-phase polymerization tank to obtain polyolefin-containing particles, transferring the polyolefin-containing particles to a second gas-phase polymerization tank through a transfer pipe, and polymerizing an olefin in the presence of the transferred polyolefin-containing particles in the second gas-phase polymerization tank. A connection place between the first gas-phase polymerization tank and the transfer pipe is higher than a connection place between the second gas-phase polymerization tank and the transfer pipe. 130 kPaP.sub.1P.sub.20 is satisfied, where P.sub.1 represents the pressure in the first gas-phase polymerization tank and P.sub.2 represents the pressure in the second gas-phase polymerization tank.

A reaction chamber for a chemical reactor comprises a casing (100) of the reaction chamber, a floor (200) of the reaction chamber having an opening (300) located in the floor, an agitator shaft (400) located in the chamber and having at least one agitator element (500), connected thereto, wherein the agitator shaft (400), seen in the longitudinal direction, has a beginning (600) and an end (700). In the opening (300) of the floor (200) a removable sleeve (800) is provided, which projects out of the reaction chamber. The sleeve (800) is arranged in alignment with the axis of rotation of the agitator shaft (400). The internal diameter of the sleeve (800) is greater than the diameter of the agitator shaft (400) and the agitator shaft (400), at the beginning (600) thereof and/or at the end (700) thereof, is adapted to absorb reversibly a torque provided by means of a further shaft and/or to transmit a torque to a further shaft. Using such a reaction chamber, it is possible to build up modular chemical reactors having decreased backmixing.

Methods of generating performic acid by contacting aqueous oxidizing agent and aqueous formic acid source in liquid phase are disclosed. A system and apparatus for the in situ production of the performic acid chemistries is further disclosed. In particular, a continuous flow reactor is provided to generate performic acid at variable rates. Methods of employing the oxidizing biocide for various disinfection applications are also disclosed.

In a method for monitoring a chemical reaction in a continuously operated reactor with at least one tube section, wherein the reactor has an intake, an outlet and a main flow direction running between the intake and the outlet, substances are supplied to the reactor via the intake and a product mixture made up of these substances and the solidified products thereof is created in the reactor. The reaction is monitored and measures are taken to prevent an uncontrolled reaction process, wherein these measures comprise at least the following steps: interruption of the intake and outlet, active pressure relief of the reactor and flushing of the reactor with an inert substance. This facilitates a safe and efficient interruption of the chemical reaction.

A rotary feeder comprising a stationary, cylindrical housing having disposed therein a number of injection nozzles, and within which rotate a plurality of vanes about a central axis, wherein the housing extends a width along the central axis, wherein each of the vanes has a length along the central axis, and wherein the injection nozzles are positioned across the width of the housing, such that a spray pattern of a gas injected via the number of injection nozzles spans substantially the entire length of the vanes. A system comprising and a method utilizing such a rotary feeder are also provided herein.

The present invention relates to an optimized process for preparing methacrylic acid, wherein methacrolein is prepared in a first stage from propionaldehyde and formaldehyde by means of a Mannich reaction and oxidized in a second stage to methacrylic acid. More particularly, the present invention relates to the reduction in the amounts of catalyst to be used in the first stage, especially to the reduction in the amounts of acid to be used here, by virtue of the additional installation of recycling streams suitable for the purpose.

The purpose of the present invention is to provide a method for continuously producing a ketomalonic acid compound such as a ketomalonic acid diester or a hydrate thereof, which is an industrially useful compound, on an industrial scale and in a safe and steady manner. The present invention relates to: a method in which a malonic acid diester, a carboxylic acid compound and a chlorous acid compound are used as raw material compounds, and these raw material compounds are mixed together to prepare a mixture and the mixture is supplied to a flow reactor continuously, thereby continuously producing a corresponding ketomalonic acid diester or a hydrate thereof; and a continuous production apparatus for performing the method.