Processes for the treatment of waste streams from the hydroconversion of heavy hydrocarbons containing additives and catalysts are described. At least one of the SHC pitch stream, SDA pitch stream, and the heavy residue stream is sent to a thermal oxidation system. The metals in the SHC and SDA pitch streams and the heavy residue stream are oxidized and can be easily recovered as clean powdered metal oxides which can be reused or sold. The processes produce chemicals which can be recovered and sold.

A process for cleaning process gas removes sulfur oxides (SOx), nitrogen oxides (NOx), and particulate matter (PM) to produce a tail gas substantially free of these pollutants. The process oxidizes and absorbs SOx and NOx for storage as liquid acids. In some embodiments a PM removal stage and/or a SOx removal stage are provided in a close-coupled higher-pressure environment upstream from a turbocharger turbine. The process has example application in cleaning exhaust gases from industrial processes and large diesel engines such as ship engines.

Tar-like components can be removed from gas streams resulting from gasification of coal, waste or biomass by contacting the gas with a liquid organic aryl polysiloxane. The polysiloxane preferably contains alkyl groups and aryl groups, and is in particular a polymethyl polyphenyl polysiloxane. The gas comprises one or more of hydrogen, carbon monoxide, carbon dioxide, and methane.

A dust collecting system for single crystal growth system includes an air compressor, a dust collecting device, a first inert gas source, a rotary pump and a scrubber. The air compressor is fluidly connected to an exit pipe of the single crystal growth system. The exit pipe is used to exhaust unstable dust from the single crystal growth system. The dust collecting device is fluidly connecting to the exit pipe to collect the dust oxide. The first inert gas source is fluidly connected to the exit pipe to blow a first inert gas into the exit pipe to compel the dust oxide toward the dust collecting device. The rotary pump is fluidly connected to the dust collecting device. The scrubber is fluidly connected to the rotary pump. The rotary pump transports the residual dust oxide toward the scrubber. The present disclosure further provides a method for collecting dust.

The present invention relates to a process for removing carbon dioxide from synthesis gas using a hygroscopic, physical absorption medium. The process includes cooling the absorption medium and the synthesis gas; water is at least partially removed from the synthesis gas by condensation; carbon dioxide is removed from the cooled synthesis gas via the cooled absorption medium in a physical absorption step at elevated pressure; laden absorption medium is treated in a plurality of serially arranged flash stages, wherein co-absorbed carbon monoxide and hydrogen are removed from the laden absorption medium in at least one first flash stage, and carbon dioxide is removed from the laden absorption medium in a flash stage arranged downstream of the first flash stage. The process features a high rate of separated carbon dioxide and a pure and dry (anhydrous) carbon dioxide product. The invention further relates to a plant for performing the process.

Carbonate salts are efficiently produced from carbon dioxide in exhaust gas. The method for producing carbonate salts includes an atomizing step that forms an aqueous alkaline solution mist with an atomizer; a mixing step that mixes exhaust gas with the aqueous alkaline solution mist produced in the atomizing step to absorb exhaust gas carbon dioxide in the mist and combine mist positive ions with the carbon dioxide to produce mist that contains carbonate salt; and a separating step that separates the mist that contains carbonate salt produced in the mixing step from exhaust gas.

The present invention discloses methods for extracting and recycling hydrogen in an MOCVD process by FTrPSA. Through pretreatment, fine deamination, PSA hydrogen extraction, deep dehydration and hydrogen purification procedures, ammonia-containing waste hydrogen from an MOCVD process is purified to meet the electronic-level hydrogen (the purity is greater than or equal to 99.99999% v/v) standard required by the MOCVD process, to implement resource reuse of exhaust gases, where the hydrogen yield is greater than or equal to 75-86%. The present invention solves the technical problem that atmospheric-pressure or low-pressure waste hydrogen from MOCVD processes cannot be returned to the MOCVD processes for use after being recycled, and fills the gap in green and circular economy development of the LED industry.

A method for collecting dust from a single crystal growth system includes providing dry air and oxygen into an exit pipe connecting to the single crystal growth system, blowing a first inert gas into the exit pipe to compel the dust oxide toward a dust collecting device, collecting the dust oxide by the dust collecting device; and providing a rotary pump to transport residues of the dust oxide backward. The oxygen reacts with the unstable dust for forming dust oxide. The exit pipe is used to exhaust unstable dust from the single crystal growth system.

The present invention relates to a process for removing carbon dioxide from synthesis gas using a hygroscopic, physical absorption medium. The process includes cooling the absorption medium and the synthesis gas; water is at least partially removed from the synthesis gas by condensation; carbon dioxide is removed from the cooled synthesis gas via the cooled absorption medium in a physical absorption step at elevated pressure; laden absorption medium is treated in a plurality of serially arranged flash stages, wherein co-absorbed carbon monoxide and hydrogen are removed from the laden absorption medium in at least one first flash stage, and carbon dioxide is removed from the laden absorption medium in a flash stage arranged downstream of the first flash stage. The process features a high rate of separated carbon dioxide and a pure and dry (anhydrous) carbon dioxide product. The invention further relates to a plant for performing the process.

Method and installation for treating a CO.sub.2- and H.sub.2O-containing flue gas generated by an industrial process unit before CCUS, whereby the flue gas evacuated from the unit is subjected to cooling to a temperature T2 between 100 and 600° C., whereby the cooled flue gas is pretreated in one or more particle removal and/or gas cleaning and/or drying stages and the temperature of the cooled flue gas is further reduced to a temperature T3<T2, before a first part of pretreated flue gas is subjected to CCUS, a second part of the pretreated flue gas being recycled at temperature T3 as a cooling agent and mixed with the flue gas during the controlled cooling thereof, partially or fully purified CO.sub.2 from the CCUS may be recycled at temperature T4<T2 may be recycled as a cooling agent and mixed with the flue gas during the controlled cooling.