A process for polymerizing olefin monomer(s) in a gas-solids olefin polymerization reactor comprising 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; comprising the following steps: introducing a fluidization gas stream into the bottom zone; polymerizing olefin monomer(s) in the presence of a polymerization catalyst in a dense phase formed by particles of a polymer of the olefin monomer(s) 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; wherein the kinetic energy (E.sub.JG) input in the reactor by the jet stream is between 1.5 and 50 times higher than the kinetic energy (E.sub.FG) input in the reactor by the fluidization gas stream (FG).

A process plant and a process for production of sulfur from a feedstock gas including from 15% to 100 vol % H.sub.2S and a stream of sulfuric acid, the process including a) providing a Claus reaction furnace feed stream with a substoichiometric amount of oxygen, b) directing to a Claus reaction furnace operating at elevated temperature, c) cooling to provide a cooled Claus converter feed gas, d) directing to contact a material catalytically active in the Claus reaction, e) withdrawing a Claus tail gas and elementary sulfur, f) directing a stream comprising said Claus tail gas to a Claus tail gas treatment, wherein sulfuric acid directed to said Claus reaction furnace is in the form of droplets with 90% of the mass of the droplets having a diameter below 500 μm, with the associated benefit of such a process efficiently converting all liquid H.sub.2SO.sub.4 to gaseous H.sub.2SO.sub.4 and further to SO.sub.2.

Provided herein are absorbent polymers produced from beta-propiolactone, and methods and systems of producing such polymers. The beta-propiolactone may be derived from ethylene oxide and carbon monoxide. The absorbent polymer may be bio-based and/or biodegradable. The absorbent polymers may be used for diapers, adult incontinence products, and feminine hygiene products, as well as for agricultural applications.

Provided are an apparatus and a method for manufacturing high-pressure method low-density polyethylene, the apparatus and the method having excellent characteristics that a chain transfer agent can be supplied by a simpler apparatus, a deviation (variation) of the concentration of the chain transfer agent supplied to a reactor can be reduced, and compression energy of the chain transfer agent can be reduced. An apparatus for manufacturing high-pressure method polyethylene includes a chain transfer agent supply line that is a line connected to a low pressure recycle ethylene supply line for supplying a chain transfer agent.

Provided are an apparatus and a method for manufacturing high-pressure method low-density polyethylene, the apparatus and the method having excellent characteristics that the amount of smoke generated during processing of a polyethylene to be obtained is small, and the number of fish eyes contained in a film formed from the polyethylene is small. An apparatus for manufacturing high pressure method polyethylene includes: an ethylene supply line that is a line branched from a high pressure recycle ethylene line and connected to a recycle ethylene holding drum for decompressing high pressure recycle ethylene from the high pressure recycle ethylene line and supplying the decompressed recycle ethylene to the recycle ethylene holding drum; and the recycle ethylene holding drum that is a drum for holding the decompressed recycle ethylene through the ethylene supply line.

A method for operating a plant for synthesizing methanol, wherein a synthesis gas flow having hydrogen and carbon oxides is supplied to a synthesis gas compressor of the plant to increase the pressure of the synthesis gas flow. The pressure-increased synthesis gas flow is supplied to a methanol reactor arrangement of the plant for partial conversion to methanol. The plant has a hydrogen recovery arrangement which obtains an H-recycling flow including hydrogen from a recovery flow supplied from the methanol reactor arrangement, which hydrogen is converted at least in part to methanol. Upon failure of the synthesis gas compressor, the synthesis gas flow continues to be supplied to the methanol reactor arrangement for partial conversion to methanol. Following failure of the synthesis gas compressor, a line arrangement of the plant is switched such that the H-recycling flow is adjusted to compensate for a pressure loss in the methanol reactor arrangement.

The invention relates to a chemical plant comprising a reforming section arranged to receive a feed gas comprising hydrocarbons and provide a synthesis gas, wherein the reforming section comprises: an electrically heated reforming reactor housing a first catalyst, said electrically heated reforming reactor being arranged for receiving said feed gas and generating a first synthesis gas; and an autothermal reforming reactor downstream said electrically heated reforming reactor, said autothermal reforming reactor housing a second catalyst, said autothermal reforming reactor being arranged for receiving said first synthesis gas and outputting a second synthesis gas, wherein said reforming section is arranged to output said output synthesis gas comprising said second synthesis gas. The invention also relates to a process for producing a chemical product from a feed gas comprising hydrocarbons, in a chemical plant according to the invention.

A process for synthesizing methanol may involve supplying a CO2 stream consisting predominantly of carbon dioxide and an H stream consisting predominantly of hydrogen to a methanol reactor arrangement for conversion to methanol. A tail gas stream comprising unreacted hydrogen may be obtained from the methanol reactor arrangement. The unreacted hydrogen may be at least partly recycled to the methanol reactor arrangement. The tail gas stream is supplied to a hydrogen recovery arrangement to obtain a return stream comprising the unreacted hydrogen. The molar proportion of hydrogen in the return stream may be higher than in the tail gas stream.

Disclosed is an external circulating slurry reactive crystallizer, including a riser, a degassing zone and a downcomer. A lower end of the riser is communicated with a gas inlet pipe, a liquid inlet pipe and a solid feeding pipe, while an upper end of the riser is communicated with a lower end of the degassing zone. An upper end of the downcomer is integrally fixed to a sidewall of the degassing zone. At least one hydrocyclone is arranged at a lower end of the downcomer. The hydrocyclone is provided with an overflow port at an upper end thereof and an underflow port and a valve at a lower end thereof. The overflow port is communicated with the riser. The crystallizer can simultaneously realize reaction, crystallization and separation for continuous production with low cost, regulating and controlling the particle size distribution and morphology of crystals.

A reactive process for converting composite plastic waste into hydrogen gas and a reactor system for effecting such process.