A process for treating effluent streams in a renewable transportation fuel production process is described. One or more of the sour water stream and an acid gas stream are treated directly in thermal oxidation section. The process allows the elimination or size reduction of a sour water stripper unit, waste water treatment plant, and sulfur recovery unit.

Disclosed are a flue gas purification and waste heat utilization system and method. The system comprises a flue gas exhaust unit, a primary waste heat utilization unit, a primary flue gas purification unit, a secondary waste heat utilization unit and a secondary flue gas purification unit that are sequentially connected in a flue gas flow direction, wherein the primary flue gas purification unit is configured for removing NO.sub.x, large particles and CO in the flue gas, the secondary flue gas purification unit is configured for removing NO.sub.x and dioxin in the flue gas, an ammonia-spraying device is externally connected between the flue gas exhaust unit and the primary waste heat utilization unit, and the ammonia-spraying device is configured for injecting ammonia gas into the flue gas exhausted from the flue gas exhaust unit.

Disclosed are a flue gas purification and waste heat utilization system and method. The system comprises a flue gas exhaust unit, a primary waste heat utilization unit, a primary flue gas purification unit, a secondary waste heat utilization unit and a secondary flue gas purification unit that are sequentially connected in a flue gas flow direction, wherein the primary flue gas purification unit is configured for removing NO.sub.x, large particles and CO in the flue gas, the secondary flue gas purification unit is configured for removing NO.sub.x and dioxin in the flue gas, an ammonia-spraying device is externally connected between the flue gas exhaust unit and the primary waste heat utilization unit, and the ammonia-spraying device is configured for injecting ammonia gas into the flue gas exhausted from the flue gas exhaust unit.

A gas processing furnace according to the present invention includes: a heater body filled with an electric heating element; and a tubular gas passage passing through the heater body. The gas processing furnace includes: a block-like heater body extending in the up-down direction and filled with the electric heating element; gas passages passing through the heater body in the up-down direction, the gas passages being consecutively disposed or extended in the front-back direction, the gas passages being arranged so as to form a plurality of arrays parallel to each other in the right-left direction, in a plan view; and a headbox mounted at an upper end portion of the heater body and configured to allow the gas passages to communicate with each other via a communication space formed inside the headbox.

A method of optimising operating conditions in an abatement apparatus configured to treat an effluent stream from a processing tool and an abatement apparatus are disclosed. The method of optimising operating conditions in an abatement apparatus configured to treat an effluent stream containing PFC from a processing tool comprise: changing an operating parameter which controls an operating condition of the abatement apparatus; determining a change in a PFC concentration present in an exhaust stream of the abatement apparatus; and determining whether to retain the operating parameter based on the change in the PFC concentration. In this way, the concentration of PFC present in the exhaust can be used to determine whether the abatement apparatus is operating under the correct operating conditions or not.

A method of optimising operating conditions in an abatement apparatus configured to treat an effluent stream from a processing tool and an abatement apparatus are disclosed. The method of optimising operating conditions in an abatement apparatus configured to treat an effluent stream containing PFC from a processing tool comprise: changing an operating parameter which controls an operating condition of the abatement apparatus; determining a change in a PFC concentration present in an exhaust stream of the abatement apparatus; and determining whether to retain the operating parameter based on the change in the PFC concentration. In this way, the concentration of PFC present in the exhaust can be used to determine whether the abatement apparatus is operating under the correct operating conditions or not.

Novel methods for pretreating a rare-gas-containing stream exiting an etch chamber followed by recovering the rare gas from the pre-treated, rare-gas containing stream are disclosed. More particularly, the invention relates to the pretreatment and recovery of a rare gas, such as xenon or krypton, from a nitrogen-based exhaust stream with specific gaseous impurities generated during an etch process that is performed as part of a semiconductor fabrication process.

A process for producing ethylene glycol and/or ethylene carbonate, said process comprising contacting at least a portion of a recycle gas stream comprising an alkyl iodide impurity with a guard bed system positioned upstream of an ethylene oxide reactor to produce a treated recycle gas stream, wherein the guard bed system comprises silver on alumina; contacting an epoxidation feed stream comprising an ethylene feed stream, oxygen, chloride moderator, and at least a portion of the treated recycle gas stream with an epoxidation catalyst in the ethylene oxide reactor to produce an epoxidation reaction product comprising ethylene oxide; and contacting at least a portion of the epoxidation reaction product comprising ethylene oxide with a liquid absorbent in the presence of an iodide-containing catalyst in an absorber to produce a product stream comprising ethylene carbonate and/or ethylene glycol and the recycle gas stream comprising the alkyl iodide impurity.

A process for producing ethylene glycol and/or ethylene carbonate, said process comprising contacting at least a portion of a recycle gas stream comprising an alkyl iodide impurity with a guard bed system positioned upstream of an ethylene oxide reactor to produce a treated recycle gas stream, wherein the guard bed system comprises silver on alumina; contacting an epoxidation feed stream comprising an ethylene feed stream, oxygen, chloride moderator, and at least a portion of the treated recycle gas stream with an epoxidation catalyst in the ethylene oxide reactor to produce an epoxidation reaction product comprising ethylene oxide; and contacting at least a portion of the epoxidation reaction product comprising ethylene oxide with a liquid absorbent in the presence of an iodide-containing catalyst in an absorber to produce a product stream comprising ethylene carbonate and/or ethylene glycol and the recycle gas stream comprising the alkyl iodide impurity.

Process and apparatus (10) are disclosed for capturing and converting an ozone-depleting alkyl halide fumigant from a fumigant/air mixed stream (14) by absorbing it into a metal hydroxide-alcohol buffer solution (26) in an absorber/scrubber (12) to produce a fumigant-free air stream (28). The captured alkyl halide in aqueous alcohol solution can actively react with the metal hydroxide in alcohol solution to produce a value-added product, such as a precipitate metal halide, and another alcohol that further enhances absorption. The absorbing solution is well-mixed with make-up alcohol and alkali streams to maintain the concentration of the metal hydroxide in the desired buffer solution range. The solid precipitate metal halide (52) is separated from the liquid stream, and the metal hydroxide-containing mixed alcohol stream (26) is recycled to the absorber/scrubber (12).