Methods and systems for treating volatile organic compounds (VOCs) generated in a hydrocarbon treating process are disclosed. An effluent stream containing the VOCs, as well as carbon dioxide (CO.sub.2) is combined with hot exhaust gas from a turbine and provided to a waste heat recovery unit (WHRU). The WHRU is adapted to contain a catalyst bed containing oxidation catalyst capable of effecting the oxidation of the VOCs. The temperature of the catalyzing reaction can be tailored based on the position of the catalyst bed within the temperature gradient of the WHRU. The methods and systems described herein solve the problem of effecting the removal of VOCs from the effluent. Heating the CO.sub.2-containing effluent in the WHRU also lend buoyancy to the effluent, thereby facilitating its dispersal upon release.

A pre-tensioned bearing assembly, including: a first rolling bearing including a first outer ring, first inner ring including a first cylindrical surface, and a plurality of rolling elements radially disposed between the first inner and outer rings; a second rolling bearing including a second outer ring, a second inner ring including a second cylindrical surface, and a plurality of rolling elements radially disposed between the second inner and outer rings; a shaft including a shoulder in contact with the second rolling bearing; a first conically-shaped sleeve in contact with the first cylindrical surface and the second cylindrical surface, and including a conical inner surface; a second conically-shaped sleeve in contact with the conical inner surface; and a shaft nut including an internal thread in cooperation with the shaft, and fixing the first inner ring and the second inner ring axially onto the shaft.

A synergetic system for waste treatment is provided. The synergetic system includes a waste treatment system configured to perform biological treatment of waste. Additionally, the synergetic system includes a gas purification system configured to purify exhaust gas generated during the biological treatment of the waste. The synergetic system further includes a feeding system configured to feed excess heat from the gas purification system back to the waste treatment system. The waste treatment system is further configured to use the fed back excess heat for the biological treatment of the waste.

Methods of sequestering carbon dioxide (CO.sub.2) are provided. Aspects of the methods include contacting an aqueous capture ammonia with a gaseous source of CO.sub.2 under conditions sufficient to produce an aqueous ammonium carbonate. The aqueous ammonium carbonate is then combined with a cation source under conditions sufficient to produce a solid CO.sub.2 sequestering carbonate and an aqueous ammonium salt. The aqueous capture ammonia is then regenerated from the from the aqueous ammonium salt. Also provided are systems configured for carrying out the methods.

Systems and techniques may be used for incorporating direct air carbon dioxide capture capabilities into a working fluid condensing process of a geothermal power plant. An example technique may include causing, using fans, air to flow across condenser coils of a condensing unit, through which power cycle working fluid is circulated, and through a direct air capture (DAC) filtration component, which separates carbon from the air, capturing heat from a geothermal working fluid, and using the heat as thermal energy input to the DAC filtration component or using electrical energy generated from the geothermal power plant as electrical energy input to power the condensing unit and the DAC filtration component. The example technique may include gathering the carbon separated from the air to be injected into a geothermal reservoir or repurposed for another industrial process.

A flue gas can be cooled for carbon capture purposes with the use of a gas-to-gas exchanger, using air as the cooling media, downstream of a heat recovery process, and optionally upstream of a quenching process; the use of an amine chilling process to reduce the required flue gas cooling duties upstream of the CO.sub.2 absorber; the use of a gas-to-gas exchanger, using the absorber overhead as the cooling media, downstream of a heat recovery process, and optionally upstream of the quenching process; and/or the use of a quenching process in which heated water and condensate is cooled by an external cooling loop utilizing treated flue gas condensate in an evaporative cooling process.

This present invention describes methods and systems for integrating liquid-phase, electrochemical and chemical processes into power generation, petrochemical, metal, cement and other industrial process plants, in such a manner as to capture and recycle all input carbon into cost-competitive hydrogen, oxygen and hydrocarbons. These integrated systems will recover internally generated losses in chemical potential (AG Gibbs Free or Available Energy) as well as waste heat (ΔH—Enthalpy), and sometimes electricity, to assist in driving these electrochemical and chemical processes, which will increase the total useful output of the process plants, thereby increasing thermal, carbon and economic efficiency.

An apparatus for disposing of organic or sewage sludge waste includes: a storage tank configured to collect and accommodate organic or sewage sludge waste; an agitator which is connected to the storage tank to decompose and dry the organic or sewage sludge waste supplied from the storage tank; a first deodorizer which is connected to one side of the agitator to biologically decompose and remove bad-odour substances from a waste gas generated during an agitating process of the organic or sewage sludge waste; a second deodorizer which heats and removes bad-odour substances contained in the waste gas from which the bad-odour substances have been partially removed by the first deodorizer; and a heat exchanger which heats the waste gas, which flows in the second deodorizer, through heat of the waste gas discharged from the second deodorizer.

A method for producing a synthetic fuel from hydrogen and carbon dioxide comprises extracting hydrogen molecules from hydrogen compounds in a hydrogen feedstock to produce a hydrogen-containing fluid stream; extracting carbon dioxide molecules from a dilute gaseous mixture in a carbon dioxide feedstock to produce a carbon dioxide containing fluid stream; and processing the hydrogen and carbon dioxide containing fluid streams to produce a synthetic fuel. At least some thermal energy and/or material used for at least one of the steps of extracting hydrogen molecules, extracting carbon dioxide molecules, and processing the hydrogen and carbon dioxide containing fluid streams is obtained from thermal energy and/or material produced by another one of the steps of extracting hydrogen molecules, extracting carbon dioxide molecules, and processing the hydrogen and carbon dioxide containing fluid streams.

A process for hydrotreating a feed stream comprising a biorenewable feedstock is disclosed. The process comprises hydrotreating the feed stream in the presence of a hydrotreating hydrogen stream and a hydrotreating catalyst to provide a hydrotreated stream. The hydrotreated stream is separated into a hydrotreated liquid stream and a hydrotreated gas stream. The hydrotreated liquid stream is subjected to stripping to provide a stripper off-gas stream. At least a portion of the stripper off-gas stream is contacted with a caustic stream to provide a sulfur-lean gas stream and a sulfur-rich caustic stream. The sulfur-rich caustic stream is further treated to provide a treated gas stream.