The invention relates to a method and to a plant for chemical looping oxidation-reduction combustion (CLC) of a gaseous hydrocarbon feed, for example natural gas essentially containing methane. According to the invention, catalytic steam reforming of the feed is performed between two successive feed combustion steps on contact with an oxidation-reduction active mass in form of particles. The reforming catalyst is arranged in a fixed bed in an intermediate reforming zone (130) between the two reduction zones (120, 140) where the two combustion steps are conducted.

FIG. 2 to be published.

Assembly of a fluidized bed reactor for the preparation of polycrystalline silicon granules by chemical vapor deposition of silicon onto seed particles and removal of polycrystalline silicon granules is facilitated without breakage and with gas tightness by a specific assembly sequence.

A reactor comprises a reactor vessel defining a confined reactor volume, a support assembly extending about a periphery of the confined reactor volume, a basket positioned within the reactor vessel and supported by the support assembly, the basket having an interior surface and an exterior surface, a downflow zone being defined between the exterior surface of the basket and an interior surface of the confined reactor volume, an inlet screen positioned adjacent to one end of the interior surface and an outlet screen positioned adjacent to an opposite end of the interior surface, an upflow zone defined between the inlet screen and outlet screen, the inlet screen and the outlet screen containing a quantity of particulate catalyst, and a circulating device positioned above said upflow zone and configured to continuously circulate fluid upwardly though said upflow zone and downwardly through said downflow zone, the support assembly and the basket configured to promote the formation of a fluid vortex within a portion of the downflow zone.

A fluidized bed biogasifier is provided for gasifying biosolids. The biogasifier includes a reactor vessel and a feeder for feeding biosolids into the reactor vessel at a desired feed rate during steady-state operation of the biogasifier. A fluidized bed in the base of the reactor vessel has a cross-sectional area that is proportional to at least the fuel feed rate such that the superficial velocity of gas is in the range of 0.1 m/s (0.33 ft/s) to 3 m/s (9.84 ft/s). In a method for gasifying biosolids, biosolids are fed into a fluidized bed reactor. Oxidant gases are applied to the fluidized bed reactor to produce a superficial velocity of producer gas in the range of 0.1 m/s (0.33 ft/s) to 3 m/s (9.84 ft/s). The biosolids are heated inside the fluidized bed reactor to a temperature range between 900° F. (482.2° C.) and 1700° F. (926.7° C.) in an oxygen-starved environment having a sub-stoichiometric oxygen level, whereby the biosolids are gasified.

A method of producing a composite product is provided. The method includes providing a fluidized bed of metal oxide particles in a fluidized bed reactor, providing a catalyst or catalyst precursor in the fluidized bed reactor, providing a carbon source in the fluidized bed reactor for growing carbon nanotubes, growing carbon nanotubes in a carbon nanotube growth zone of the fluidized bed reactor, and collecting a composite product comprising metal oxide particles and carbon nanotubes.

The present invention discloses a continuous calcination vessel which can be used to prepare calcined chemically-treated solid oxides from solid oxides and chemically-treated solid oxides. A process for the continuous preparation of calcined chemically-treated solid oxides is also provided. Calcined chemically-treated solid oxides disclosed herein can be used in catalyst compositions for the polymerization of olefins.

Processes and systems are disclosed for improving the yield from reforming processes. Aromatic complex bottoms, or a heavy fraction thereof, are subjected to catalytic conversion to produce additional gasoline and higher-quality aromatic compounds.

A process for the production of polyolefins comprising: feeding a slurry comprising at least one polymerization catalyst, at least one carrier liquid, first olefin monomer(s) and optionally at least one first comonomer into at least one loop reactor; polymerizing the first olefin monomer(s) and optionally the at least one first comonomer yielding a first polyolefin; withdrawing the first polyolefin from the loop reactor; feeding the first polyolefin to a gas-solids olefin polymerization reactor, wherein the gas-solids olefin polymerization reactor comprises: a top zone; a middle zone, which comprises a top end in direct contact with said top zone and which is located below said top zone, the middle zone having a generally cylindrical shape; and a bottom zone, which is in direct contact with a bottom end of the middle zone and which is located below the middle zone; introducing a fluidization gas stream into the bottom zone of the gas-solids olefin polymerization reactor; polymerizing second olefin monomer(s) and optionally at least one second comonomer in the presence of the polymerization catalyst and the first polyolefin to a second polyolefin in a dense phase formed by particles of said second polyolefin suspended in an upwards flowing stream of the fluidization gas in the middle zone; introducing a jet gas stream through one or more jet gas feeding ports in a jet gas feeding area of the middle zone at the dense phase in the middle zone of the gas-solids olefin polymerization reactor; withdrawing the second polyolefin from the gas-solids olefin polymerization reactor.

An olefin polymerisation method and arrangement comprising polymerising at least one olefin in gas phase in a fluidised bed in the presence of an olefin polymerisation catalyst in a polymerisation reactor having a vertical body; a generally conical downwards tapering bottom zone; a generally cylindrical middle zone, above and connected to said bottom zone; and a generally conical upwards tapering top zone above and connected to said middle zone wherein (i) fluidisation gas is introduced to the bottom zone of the reactor from where it passes upwards through the reactor; (ii) the fluidisation gas is withdrawn from the top zone of the reactor; (iii) a fluidised bed is formed within the reactor where the growing polymer particles are suspended in the upwards rising gas stream; and wherein the polymerisation reactor has an operating temperature set point and which reactor comprises at least one temperature measurement sensor, wherein a temperature difference (DT) between the temperature measurement sensor (Tm), and the operating temperature set point (Ts) of the reactor is equal to or less than 10° C.

The invention relates to a method for converting a gas into methane (CH.sub.4) which includes: a step of activating a catalytic material including praseodymium oxide (Pr.sub.6O.sub.11) associated with nickel oxide (NiO) and alumina (Al.sub.2O.sub.3), the respective proportions of which are, relative to the total mass of these three compounds: Pr.sub.6O.sub.11: 1 wt % to 20 wt %, NiO: 1 wt % to 20 wt %, and Al.sub.2O.sub.3: 60 to 98 wt %; and a step of passing a gas including at least one carbon monoxide (CO) over the activated catalytic material.