Abstract: Industrial gas streams such as flue gas streams are treated for nitrogen oxides and other contaminants in dry or semi-dry scrubbers. After the flue gas stream has been contacted with a sorbent, ozone is mixed downstream into the flue gas stream thereby oxidizing the nitrogen oxides and other contaminants. The oxidized contaminants is contacted with sorbent present in the gas stream in the remaining height or volume of the scrubber downstream of ozone injection; and The sorbent is then separated from the flue gas stream leaving the dry or semi-dry scrubber.

Abstract: A flue gas stream arising from fossil fuel fired sources containing nitrogen oxide contaminants is conveyed through an exhaust duct into a quencher. In the quencher aqueous medium is sprayed into contact with the flue gas stream. The quenched flue gas stream is mixed with ozone distributed at a high velocity in a sub-stoichiometric amount for partial oxidation of NOxto form NO2 and prevent the formation of N2O5. The flue gas containing NO2 is absorbed into an acidic medium of a wet scrubber to form nitrous acid. In the scrubber the nitrous acid is mixed with selected compounds of ammonia to decompose the nitrous acid for release of nitrogen. With this process the consumption of ozone and the operating costs associated therewith eliminate the requirement to dispose of nitrate recovered from the scrubber purge stream.

Abstract: A flue gas stream arising from fossil fuel fired sources containing nitrogen oxide contaminants is conveyed through an exhaust duct into a quencher. In the quencher aqueous medium is sprayed into contact with the flue gas stream. The quenched flue gas stream is mixed with ozone distributed at a high velocity in a sub-stoichiometric amount for partial oxidation of NOxto form NO2 and prevent the formation of N2O5. The flue gas containing NO2 is absorbed into an acidic medium of a wet scrubber to form nitrous acid. In the scrubber the nitrous acid is mixed with selected compounds of ammonia to decompose the nitrous acid for release of nitrogen. With this process the consumption of ozone and the operating costs associated therewith eliminate the requirement to dispose of nitrate recovered from the scrubber purge stream.

Abstract: A method for removing contaminants from a gas stream by feeding the gas stream into a scrubber that can use seawater as the scrubbing medium. The gas stream is first scrubbed with the seawater and then mixed with ozone to remove the contaminants. Nitrogen oxides that are present in the gas stream are converted to nitric acid/nitrates and these are recovered via condensate or coalesced mist for neutralization. The treated gas stream is then treated by a second scrubber whereby other contaminants such as sulfur oxides, particulates and the like are removed and the thus treated gas stream is exhausted to the atmosphere. Optionally a droplet separator may be present in the scrubber.

Abstract: An exhaust gas stream from a combustion process is conveyed through a gas distributor at an inlet of a wet horizontal spray scrubber where it is partitioned into a plurality of spaced apart gas streams. The gas stream is partitioned in the scrubber without the need for any physical partitions. A preselected number of the partitioned gas streams are mixed with ozone to oxidize the contaminants. The oxidized gas streams are then sprayed with an aqueous medium to capture the oxidized contaminants and remove them from the treated gas streams. The treated gas streams are then recombined with the untreated gas streams. Excess ozone present in the treated gas streams is consumed by oxidation of contaminants in the untreated gas streams before the combined gas stream is released to the atmosphere.

Abstract: A method for removing contaminants from the combustion gases generated by the incineration of waste. Air is injected into an incineration device along with a fuel and is supplemented by a oxygen feed. The resulting combustion waste gas stream contains contaminants such as nitrogen oxides and is quenched, then fed to a reaction zone where it will contact ozone for a predetermined period of time. The thus treated combustion waste gas stream can be fed to a scrubber assembly where the reaction products formed by the reaction of ozone and the contaminants are removed.

Abstract: Industrial gas streams such as flue gas streams are treated for nitrogen oxides and other contaminants in dry or semi-dry scrubbers. After the flue gas stream has been contacted with a sorbent, ozone is mixed downstream into the flue gas stream thereby oxidizing the nitrogen oxides and other contaminants. The oxidized contaminants is contacted with sorbent present in the gas stream in the remaining height or volume of the scrubber downstream of ozone injection; and The sorbent is then separated from the flue gas stream leaving the dry or semi-dry scrubber.

Abstract: An apparatus for removing contaminants from a gas stream includes a reaction chamber for receiving the gas stream; a gas-liquid contact assembly disposed in the reaction chamber; a sump disposed in the reaction chamber beneath the gas-liquid contact assembly, the sump containing a liquid scrubbing agent; a first inlet in communication with the sump for providing a reactive species to the liquid scrubbing agent in the sump for producing an oxidizing solution; a second inlet in communication with the reaction chamber for providing the gas stream to the reaction chamber; and a feed line having a first end in communication with the sump and a second end in communication with the reaction chamber above the gas-liquid contact assembly for dispensing the oxidizing solution to contact the gas-liquid contact assembly.

Abstract: Pulp is delignified by forming a mixture of pulp and caustic, adding oxygen and feeding this oxygen-containing mixture to a first step reactor. The lignin in the oxygen-containing mixture will be partially delignified and will be fed to a second step reactor where the remainder of the lignin in the pulp will be delignified. In this manner, fast reacting lignin can be treated in the first step reactor and slow reacting lignin can be treated in the second reactor. The delignified pulp is recovered from the apparatus and after washing can be forwarded to a bleaching unit.

Abstract: A method for removing contaminants from the combustion gases generated by the incineration of waste. Air is injected into an incineration device along with a fuel and is supplemented by a oxygen feed. The resulting combustion waste gas stream contains contaminants such as nitrogen oxides and is quenched, then fed to a reaction zone where it will contact ozone for a predetermined period of time. The thus treated combustion waste gas stream can be fed to a scrubber assembly where the reaction products formed by the reaction of ozone and the contaminants are removed.

Abstract: A method for removing contaminants from a gas stream by feeding the gas stream into a scrubber that can use seawater as the scrubbing medium. The gas stream is first scrubbed with the seawater and then mixed with ozone to remove the contaminants. Nitrogen oxides that are present in the gas stream are converted to nitric acid/nitrates and these are recovered via condensate or coalesced mist for neutralization. The treated gas stream is then treated by a second scrubber whereby other contaminants such as sulfur oxides, particulates and the like are removed and the thus treated gas stream is exhausted to the atmosphere. Optionally a droplet separator may be present in the scrubber.

Abstract: In a method for removing a portion of contaminants, such as nitrogen oxides, from an exhaust gas stream of a combustion process, the exhaust gas stream is conveyed through a gas distributor at an inlet of a wet horizontal spray scrubber. A distributor separates the gas stream into a plurality of spaced apart partitioned gas streams. The gas stream is partitioned in the chamber of the scrubber without the need for any physical partitions or obstructions positioned in the chamber. A preselected number of the partitioned gas streams are mixed with ozone to oxidize the contaminants in the gas streams. The oxidized gas streams are then sprayed with an aqueous medium to capture the oxidized contaminants and remove them from the treated gas streams. The treated gas streams are then recombined with the untreated gas streams. Excess ozone present in the treated gas streams is consumed by oxidation of contaminants in the untreated gas streams before the combined gas stream is released to the atmosphere.

Abstract: A method for removing contaminants from the effluent from metal pickling operations by oxidizing the contaminants in the effluent, passing the oxidized effluent to a first scrubber thereby removing mixed acid vapors and some nitrogen oxides and passing these scrubbed gases to a second scrubbing system while injecting ozone into a duct between the first and the second scrubbing systems thereby to oxidize nitrogen oxides to higher oxides and scrubbing the oxidized nitrogen oxides gas stream in the second scrubbing system.

Abstract: In a method for removing a portion of contaminants, such as nitrogen oxides, from an exhaust gas stream of a combustion process, the exhaust gas stream is separated into two or more gas streams. At least one of the two or more gas streams is treated first by mixing with ozone. The treated gas stream is then fed to a scrubber where it is recombined with the untreated gas stream. Excess ozone present in the treated gas stream is consumed by oxidation of contaminants in the untreated gas stream before the combined gas stream is released to the atmosphere. The portion of the gas stream separated for mixing with ozone directly correlates to the amount of nitrogen oxides that are desired to be removed from the stream.

Abstract: A method for producing ozone for use in ozonolysis reactions. Oxygen is separated from the mixture of ozone and oxygen from an ozone generation unit and is fed back to the oxygen feed to the generation unit. Nitrogen is fed to the ozone separation unit and the mixture of nitrogen and ozone is fed to the ozonation reactor where the ozone will react with organic compounds to produce desired end products.

Abstract: A method for removing contaminants from the effluent from metal pickling operations by oxidizing the contaminants in the effluent, passing the oxidized effluent to a first scrubber thereby removing mixed acid vapors and some nitrogen oxides and passing these scrubbed gases to a second scrubbing system while injecting ozone into a duct between the first and the second scrubbing systems thereby to oxidize nitrogen oxides to higher oxides and scrubbing the oxidized nitrogen oxides gas stream in the second scrubbing system.

Abstract: A method for removing contaminants from a gas stream by feeding the gas stream into a scrubber that can use seawater as the scrubbing medium. The gas stream is first scrubbed with the seawater and then mixed with ozone to remove the contaminants. Nitrogen oxides that are present in the gas stream are converted to nitric acid/nitrates and these are recovered via condensate or coalesced mist for neutralization. The treated gas stream is then exhausted to the atmosphere.

Abstract: A method for removing contaminants from a gas stream by feeding the gas stream into a scrubber that can use seawater as the scrubbing medium. The gas stream is first scrubbed with the seawater and then mixed with ozone to remove the contaminants. Nitrogen oxides that are present in the gas stream are converted to nitric acid/nitrates and these are recovered via condensate or coalesced mist for neutralization. The treated gas stream is then exhausted to the atmosphere.

Abstract: In a method for removing a portion of contaminants, such as nitrogen oxides, from an exhaust gas stream of a combustion process, the exhaust gas stream is separated into two or more gas streams. At least one of the two or more gas streams is treated first by mixing with ozone. The treated gas stream is then fed to a scrubber where it is recombined with the untreated gas stream. Excess ozone present in the treated gas stream is consumed by oxidation of contaminants in the untreated gas stream before the combined gas stream is released to the atmosphere. The portion of the gas stream separated for mixing with ozone directly correlates to the amount of nitrogen oxides that are desired to be removed from the stream.

Abstract: An apparatus for removing contaminants from a gas stream includes a reaction chamber for receiving the gas stream; a gas-liquid contact assembly disposed in the reaction chamber; a sump disposed in the reaction chamber beneath the gas-liquid contact assembly, the sump containing a liquid scrubbing agent; a first inlet in communication with the sump for providing a reactive species to the liquid scrubbing agent in the sump for producing an oxidizing solution; a second inlet in communication with the reaction chamber for providing the gas stream to the reaction chamber; and a feed line having a first end in communication with the sump and a second end in communication with the reaction chamber above the gas-liquid contact assembly for dispensing the oxidizing solution to contact the gas-liquid contact assembly.