Abstract:
Disclosed is an optimized process and apparatus for more efficiently and economically carrying out the liquid-phase oxidation of an oxidizable compound. Such liquid-phase oxidation is carried out in a bubble column reactor that provides for a highly efficient reaction at relatively low temperatures. When the oxidized compound is para-xylene and the product from the oxidation reaction is crude terephthalic acid (CTA), such CTA product can be purified and separated by more economical techniques than could be employed if the CTA were formed by a conventional high-temperature oxidation process.
Abstract:
It is known that poorly-flowing solid materials can lead to an inhomogeneous mass flow of the solid across the discharge cross-section of a silo. If the solid in the silo is also heated or cooled the uneven mass flow can lead, for example, to local variations in temperature and/or hence to varying product properties. According to the invention, the above problem may be resolved, whereby a method and a discharge device for a solids silo and a solids silo are disclosed, permitting a controllable solids discharge evenly across the cross-section of the silo. The cross-section of the silo discharge is divided into several, preferably equivalent, partial cross-sections to which a continuously controllable discharge device is connected. The solid flow discharged from the controllable discharge devices can be collected on a continuous conveyor arranged therebelow and removed. The even solid mass discharge from the continuous discharge devices is controlled, depending on measured signals from several equivalent sensors, recording the local mass flow in the corresponding partial sections of the silo, by means of the conveyor power of the discharge device, relating to each sensor. Where electrically-conducting solids are used which are to be heated in the silo using electrodes by means of resistance heating, the control of the discharge devices is achieved with the measured current at the electrodes.
Abstract:
A device is provided for increasing the pH of an acidic aqueous stream, which may result from commercial activity in petroleum, mining, metal finishing and food processing sectors, among others. A container defines an upright reactor portion with a cross-section that increases upwardly, along with inlet and outlet conduits connected to an inlet and an outlet between which the reactor portion is located. The conical portion contains a bed of substantially water-insoluble alkaline salt particulate, such as MgSO, the bed being such that, when the pH of the inflowing aqueous stream is below 7, contact between the particulate and the aqueous stream will raise the pH of the outflowing stream to a level above that of the inflowing stream.
Abstract:
Disclosed is a method for the continuous production of crosslinked, particulate, gel-type polymers by copolymerizing a) water-soluble, monoethylenically unsaturated monomers, b) 0.001 to 5 molar percent of monomers containing at least two polymerizable groups, the percentage being relative to the monomers (a), in a mixer. The substances that are added at the beginning of the kneader are conveyed in an axial direction towards the end of the mixer. The inventive method is characterized in that at least one of the following conditions is met: i) the filling level in the kneader mixer is at least 71 percent; ii) the water-soluble, monoethylenically unsaturated monomers contain up to 150 ppm of a semicyclic ether of a hydroquinone; iii) the temperature in the polymerization zone exceeds 65° C.; iv) the kneader has a remixing rate of less than 0.33.
Abstract:
A catalyst withdrawal apparatus and method for regulating catalyst inventory in a fluid catalytic cracking catalyst (FCC) unit is provided. In one embodiment, a catalyst withdrawal apparatus for removing catalyst from a FCC unit includes a pressure vessel having a metering device coupled to a fill port. A heat dissipater is located adjacent the metering device and is adapted to cool catalyst entering the pressure vessel. A sensor is coupled to the pressure vessel arranged to provide a metric indicative of catalyst entering the pressure vessel through the metering device. In another embodiment, a method for regulating catalyst inventory in a FCC unit includes the steps of determining a change of catalyst present in a FCC unit, withdrawing catalyst from the FCC unit into an isolatable storage vessel coupled to the FCC unit, measuring the amount of catalyst disposed in the storage vessel, and removing the measured catalyst from the storage vessel.
Abstract:
Downflow catalytic reactor having a plurality of catalyst beds in which a mixture of gas and liquid are passed, the region in between subsequent catalyst beds being provided with a distributor system for the distribution and mixing of gas and liquid prior to contact with a subsequent catalyst bed, said region comprising: (a) gas injection line arranged below a catalyst support tray, (b) collector tray adapted to receive gas and liquid, (c) spillway collectors extending above the level of said collecting tray, (d) mixing chamber adapted to receive the gas and liquid descending from said spillway collectors, (e) impingement plate below said mixing chamber, (f) first distributor tray arranged below said impingement plate having a number of apertures throughout and a number chimneys, and (g) second distributor tray arranged below said first distributor tray for the redistribution of gas and liquid prior to contact with the subsequent catalyst bed, wherein the at least one chimney is provided with a distributor device that is able to divide the chimney chamber into at least two chambers.
Abstract:
Disclosed is an optimized process and apparatus for more efficiently and economically carrying out the liquid-phase oxidation of an oxidizable compound. Such liquid-phase oxidation is carried out in a bubble column reactor that provides for a highly efficient reaction at relatively low temperatures. When the oxidized compound is para-xylene and the product from the oxidation reaction is crude terephthalic acid (CTA), such CTA product can be purified and separated by more economical techniques than could be employed if the CTA were formed by a conventional high-temperature oxidation process.
Abstract:
A slurry phase reactor is designed to treat extra heavy petroleum crude in a combination of thermal-zone and catalytic-zone in a counterflow system where liquid feed is added to the top and hydrogen at the bottom. Feed enters the gas-phase thermal zone, where it passes to a liquid-phase thermal zone. In the liquid-phase thermal zone, the hydrocarbon is thermally cracked and the unreacted liquid is further passed to a catalytic-zone below in communication with the thermal-zone. Catalyst can be added or removed as required in a continuous mode without shutting down the system. The heat generated inside the catalytic cracking zone is distributed to the entire reactor as the gaseous product flows upward. Feed is brought to the reaction conditions by the heat recovered from the gas-phase zone. Reaction temperature could be controlled by feed temperature.
Abstract:
A hydrocarbon reformer system including a first reactor configured to generate hydrogen-rich reformate by carrying out at least one of a non-catalytic thermal partial oxidation, a catalytic partial oxidation, a steam reforming, and any combinations thereof, a second reactor in fluid communication with the first reactor to receive the hydrogen-rich reformate, and having a catalyst for promoting a water gas shift reaction in the hydrogen-rich reformate, and a heat exchanger having a first mass of two-phase water therein and configured to exchange heat between the two-phase water and the hydrogen-rich reformate in the second reactor, the heat exchanger being in fluid communication with the first reactor so as to supply steam to the first reactor as a reactant is disclosed. The disclosed reformer includes an auxiliary reactor configured to generate heated water/steam and being in fluid communication with the heat exchanger of the second reactor to supply the heated water/steam to the heat exchanger.
Abstract:
In a gas phase olefin polymerization process using a fluidized bed vessel, an apparatus is employed having a device for measuring temperature or temperature distribution on the external wall surface of the vessel and a controlling means which predicts the progressive state of reaction inside the vessel, calculates the difference between the measured value and a target value determined beforehand and modifies polymerization conditions in relation thereto.