Abstract: A process for treating wastewaters containing carbonaceous COD and at least one nitrogen-containing compound is disclosed comprising wet oxidizing the wastewater with an oxidizing agent at a temperature less than 373.degree. C. and a pressure sufficient to maintain a liquid water phase, to produce an oxidized wastewater containing a reduced concentration of COD. The nitrogen of the nitrogen-containing compound is substantially converted to ammonia, nitrate and nitrite. Sufficient inorganic nitrogen-containing compound is added to the oxidized wastewater to produce essentially equal concentrations of ammonia-nitrogen and nitrite-nitrogen plus nitrate-nitrogen. Mineral acid is added to the oxidized wastewater to produce a pH between 4 and 7, and optionally, a transition metal salt is added, to catalyze a thermal denitrification step. The wastewater is heated at temperatures between about 100.degree. C. and 300.degree. C. to decompose the nitrogen compounds, producing a purified wastewater.

Abstract: A method for treating a chelate bearing waste solution employs a two-step process which includes elevating the pH of the solution to a pH greater than 10 and precipitating the metal as the hydroxide out of solution, followed by treating the resultant solution with an oxidant to destroy any remaining free chelate.

Abstract: Method/system of adding solid particles to inhibit or prevent plugging in a reactor at conditions such that the temperature and pressure are at least in the vicinity of supercritical conditions for water. Particles may be added in conjunction with a pH-adjusting material, thereby inhibiting plugging in the reactor caused by addition of the pH-adjusting material. Reactor pressure may be reduced by flowing the stream through a static restriction device.

Abstract: An apparatus is provided for oxidizing an aqueous suspension of organic matter at elevated pressure. The apparatus has a reactor and an inlet for the aqueous suspension which is introduced to an upstream end of the reactor. A device for circulating the aqueous suspension through the reactor. An inlet for an oxygen containing gas introduced to the aqueous suspension. An outlet for removing treated aqueous suspension from a downstream end of the reactor and a static mixer vane arrangement for splitting, rearranging and combining the aqueous suspension as the circulating device circulates the aqueous suspension through the reactor. The improvement comprises withdrawing the treated aqueous suspension from the downstream end of the reactor and combining a major portion thereof with fresh incoming aqueous suspension. The circulating device returns the combined aqueous suspension to the reactor via the inlet for the aqueous suspension.

Abstract: The system for transferring plasma to a test substrate comprises an applicator and the test substrate. The applicator includes a blood reservoir and a filter element which separates cellular components from the blood as plasma is passed to the test substrate. The test substrate includes an absorptive element which receives the plasma from the applicator. In one embodiment, measured amounts of plasma are transferred when the absorptive element becomes saturated, thus stopping the flow of plasma. In another embodiment, excess blood and cellular components are removed from the measured plasma by disengaging the applicator from the test substrate. In another embodiment, plasma transferred to the absorptive element is eluted from the absorptive element by subsequent application of an elution medium.

Abstract: An apparatus for treating waste water streams is constructed by introducing a mixture of pre-heated waste water and an amount of a oxidant lower than that required to oxidize all the organic matter in the waste stream into the front port of an elongate tubular reaction chamber maintained at supercritical temperatures and pressures. The amount of oxidant is high enough, it initially raise the temperature of the stream in the reaction chamber to 750-1,200.degree. F. A first injection side port is located downstream from the front port of the reaction chamber at a distance at which the temperature has reached a maximum value, and 90-100% of the available oxidant has been consumed. Oxidant and water are simultaneously injected through the first port, in a manner that the amount of oxidant is adequate to oxidize to oxidize a specified amount of organic matter, and the amount of water is effective to counterbalance the heat produced by the ration of the co-injected oxidant with the respective organic matter.

Abstract: An improved process and apparatus are disclosed for the supercritical water oxidation of organic waste materials which avoids or at least substantially reduces the corrosion and solids deposition problems associated with prior art techniques. According to this invention, externally heated supercritical water is fed to a platelet tube reactor to both protectively coat its inner surface and heat the waste stream to oxidation reaction conditions. Higher reaction temperatures can be used as compared to prior art processes, which significantly improves the reaction rate and permits smaller reactors to be used. The protective film of water on the reactor inner surface, coupled with the elimination of preheating of the waste material, substantially reduces solids deposition and corrosion.

Abstract: A process and apparatus for the supercritical water oxidation of organic waste materials which avoids or at least substantially reduces the corrosion and solids deposition problems associated with prior art techniques and which provides for efficient heating of the waste material to reaction conditions. Externally heated supercritical water is fed to a compound platelet tube reactor. The compound reactor includes a reaction zone and inner (smaller) and outer (larger) concentric platelet tubes supported concentrically within a shell. The water fed to the reactor both protectively coats surfaces of the inner and outer platelet tubes facing the reaction zone and heats the waste stream to oxidation reaction conditions. Higher reaction temperatures can be used as compared to prior art processes, which significantly improves the reaction rate and permits smaller reactors to be used.

Abstract: The invention relates to an improved apparatus and method for initiating and sustaining an oxidation reaction. A fuel, such as natural gas or hazardous waste, is introduced into a reaction zone within a pressurized containment vessel. A permeable liner is placed within the containment vessel and around the reaction zone. An oxidizer, preferably oxygen, is mixed with a carrier fluid, such as water, and the mixture is heated and pressurized to supercritical conditions of temperature and pressure. The supercritical oxidizer-carrier mix is introduced to the reaction zone gradually and uniformly, over a comparatively large area, by forcing it radially inward through the permeable liner and toward the reaction zone. A means and method for cooling the exhausted by-products and using them as a cleansing rinse are disclosed.

Abstract: A process for water oxidation of combustible materials in which during at least a part of the oxidation corrosive material is present and makes contact with at least a portion of the apparatus over a contact area on the apparatus. At least a portion of the contact surface area comprises titanium dioxide coated onto a titanium metal substrate. Such ceramic composites have been found to be highly resistant to environments encountered in the process of supercritical water oxidation. Such environments typically contain greater than 50 mole percent water, together with oxygen, carbon dioxide, and a wide range of acids, bases, and salts. Pressures are typically about 27.5 to about 1000 bar while temperatures range as high as 700.degree. C. The ceramic composites are also resistant to degradation mechanisms caused by thermal stresses.

Abstract: A method for oxidizing organic material in an aqueous stream containing one or more inorganic salts, inorganic salt precursors or mixtures thereof, comprising oxidizing said organic material under supercritical conditions in the presence of an oxidant and a mobile surface of particles to which inorganic salts insoluble under the reaction conditions can adhere.

Abstract: Processes are disclosed for treating materials such as waste material, wastewater, and sludge, particularly waste activated sludge (WAS). In one aspect a process according to the present invention includes denaturing, acidifying and degassing incoming WAS while venting gases produced, preferably to a vent treatment system; feeding the resulting denatured WAS to a reactor into which are fed steam and oxygen, the steam discontinued once the reaction becomes autothermal; venting hot gases from the reactor back to the degassing step, to heat recovery or to a reactor, e.g. a sequencing batch reactor; and cooling and neutralizing the reactor product. Batch, semi-continuous, and batch sequencing methods are disclosed.

Abstract: A process for purifying a photographic waste solution is disclosed. The photographic waste solution is purified by successively performing: noncatalytic wet oxidation at a temperature of from 140.degree. C. up to 370.degree. C. under such a pressure as to hold said waste solution in a liquid phase while supplying an oxygen-containing gas thereto; solid-liquid separation of the solid matters and/or suspended matters thus formed; catalytic wet oxidation at a temperature of from 140.degree. C. up to 370.degree. C. under such a pressure as to hold said waste solution in a liquid phase while supplying an oxygen-containing gas thereto; and a biological treatment comprising a combination of an aerobic biological treatment with an anaerobic biological treatment.

Abstract: A process for hydrothermal oxidation of combustible materials in which, during at least a part of the oxidation, corrosive material is present and makes contact with at least a portion of the apparatus over a contact area on the apparatus. At least a portion of the contact surface area comprises iridium, iridium oxide, an iridium alloy, or a base metal overlaid with an iridium coating. Iridium has been found to be highly resistant to environments encountered in the process of hydrothermal oxidation. Such environments typically contain greater than 50 mole percent water, together with oxygen, carbon dioxide, and a wide range of acids, bases and salts. Pressures are typically about 27.5 to about 1000 bar while temperatures range as high as 800.degree. C.

Abstract: A supercritical water oxidation reactor is alternately supplied with a feed stream and a flushing stream. The feed stream contains organic and inorganic materials. The organic materials are oxidized under supercritical conditions in the reactor and the inorganic materials precipitate out of solution under the same conditions. The flushing stream is a solution in which the inorganic material is soluble. More than one supercritical water oxidation reactor may be connected so that the feed stream is alternately supplied to each reactor. During the period when the feed stream is being supplied to a reactor the effluent from the reactor is cooled to a temperature at which inorganic precipitates are soluble and is then supplied as a flushing stream to one or more of the remaining connected supercritical water oxidation reactors.

Abstract: A method for pretreating a halogenated hydrocarbon feed to a hydrothermal oxidation reactor which includes forming a combination of a halogenated hydrocarbon with added alkali under hydrothermal conditions, adding water to the combination, thereby effectuating hydrolysis of the halogenated hydrocarbon so as to liberate halogen ions which are neutralized by the alkali. The neutralized halogen ion, a salt, may be removed from the process prior to or during the oxidation step as brine droplets.

Abstract: A process is described for monitoring pH in caustic liquor wet oxidation systems. An offgas carbon dioxide baseline value is established for the operating system where oxidized liquid effluent is at pH 7 or above. Offgas carbon dioxide content deviating by a selected proportion above the baseline vale indicates a drop in liquid effluent pH to 7 or less. Sufficient alkalinity is added to the raw wastewater to bring the effluent pH to 7 or above and prevent excessive corrosion to the materials of construction of the nickel-based or ferrous-based alloy wet oxidation system.

Abstract: A process for the oxidation of ammonium ions and organic carbon in wastewaters containing ammonium ions and organic carbon by means of nitric acid at from 100.degree. to 350.degree. C., wherein the molar ratio between organic carbon and ammonium nitrogen is adjusted to a value in the range from 0.3:1 to 4:1 by addition of organic carbon or ammonium nitrogen.

Abstract: With the process according to the invention for the purification of salt-charged waste water by wet oxidation of organic constituents under supercritical conditions, the reaction is performed in the form of a flame (5). In this case the supercritical zone is surrounded with a subcritical by-pass flow (4) formed from cooling water. At one end of the reactor (1) constructed as a cylindrical pressure vessel are provided at least one burner nozzle (2) and at least one annular inlet point (48), surrounding the burner nozzle, for the cooling water; at the other end is disposed at least one common outlet point (160) for cooling water, reaction products and in particular precipitated salts. Thanks to the by-pass flow there are no obstructions caused by salts; and corrosion problems are substantially reduced.

Abstract: The invention greatly reduces the amount of ammonia in sewage plant effluent. The process of the invention has three main steps. The first step is dewatering without first digesting, thereby producing a first ammonia-containing stream having a low concentration of ammonia, and a second solids-containing stream. The second step is sending the second solids-containing stream through a means for separating the solids from the liquid and producing an aqueous stream containing a high concentration of ammonia. The third step is removal of ammonia from the aqueous stream using a hydrothermal process.

Abstract: The method of separating impurities from an aqueous solution by means of rotating tile aqueous solution at high speeds until a high pressure and a high temperature is reached. At that time the impurities are separated from the solution. The aqueous solution is kept at high temperatures and pressures until the impurities are separated from the liquid. Preferably, a device providing a centrifugal force, such as a centrifuge, is used to achieve the high temperatures and pressures which should preferably be no lower than 705.4.degree. F. and 3,208 psi, respectively.

Abstract: The apparatus (1) for wet oxidation is pre-assembled with its individual units, namely a high-pressure pump (2), a heat exchanger (3), a reactor (4) for the actual wet oxidation and a compressor (5) for feeding an oxygen/gas mixture, in one or two supporting flames and is accommodated in such a manner that its dimensions and its overall weight allow it to be transported on a road and/or rail vehicle, there advantageously being provided two such supporting flames in the form of standard containers (8 and 9), of which one may contain the reactor (4), divided into individual tube sections (6), and the heat exchanger (3), and the other may contain the remaining units, so that the entire apparatus can be pre-assembled into virtually operational condition and the two containers simply have to be set up, joined together and connected on site. Wet oxidation can thus be carried out even where relatively small quantities of medium are to be purified.

Abstract: A system and method for inducing flow of a dense gas through a fluid circuit without the use of a compressor or other pumping means. A heat absorption chamber has an outlet in fluid communication with the inlet of a heat rejection chamber and has an inlet in fluid communication with an outlet from the heat rejection chamber. Thermal energy absorbed by the dense gas in the heat absorption chamber causes the density of the dense gas to decrease sufficiently to cause the dense gas to flow to the heat rejection chamber. After heat energy is subsequently rejected from the heated dense gas, its density increases, and gravitational or radial acceleration forces acting thereupon induce the cooled, dense gas to flow to the heat absorption chamber displacing the dense gas therewithin. The fluid flow system of the present invention may be used for heat transfer or may be applied to processes such as solvent extraction, reduction of particle size, and oxidation of organic materials employing supercritical water.

Abstract: This invention relates to a process and apparatus for dissipating the energy of a wet oxidation mixture after that stream traverses a pressure control valve. The depressurized stream is discharged into a phase separator vessel containing a gas phase and a liquid phase. The pressure control valve is positioned to discharge the oxidation mixture at a selected orientation below the surface level of the liquid phase in the vessel. This dissipates the energy of the mixture and prevents erosion of the phase separator vessel. The apparatus of the invention includes the separator vessel with gas and liquid phase exits, a control device for maintaining the liquid phase at the selected level in the vessel, a pressure control valve positioned at an aperture in the vessel for discharging the mixture below the surface level of the liquid phase in the vessel, and sealing device between the control valve and the separator vessel.

Abstract: A process for depolymerizing polymers by selective, partial oxidation at supercritical or near supercritical conditions for water and wherein supercritical water or water near supercritical conditions is used as a solvent and reforming agent, is used to produce relatively high yields of the monomers originally used to produce the polymers. The invention provides an environmentally friendly process for recycling polymeric waste materials to generate valuable polymer feedstock in a closed oxidation process which is free of hazardous stack emissions. The polymers which can be recycled in accordance with the process can include typical amounts of conventional additive and other impurities without significantly affecting the overall conversion.

Abstract: The invention relates to an improved apparatus and method for initiating and sustaining an oxidation reaction. A fuel, such as natural gas or hazardous waste, is introduced into a reaction zone within a pressurized containment vessel. A permeable liner is placed within the containment vessel and around the reaction zone. An oxidizer, preferably oxygen, is mixed with a carrier fluid, such as water, and the mixture is heated and pressurized to supercritical conditions of temperature and pressure. The supercritical oxidizer-carrier mix is introduced to the reaction zone gradually and uniformly, over a comparatively large area, by forcing it radially inward through the permeable liner and toward the reaction zone. A means and method for cooling the exhausted by-products and using them as a cleansing rinse are disclosed.

Abstract: A mechanism for converting impurities or contaminants in a fluid to a non-hazardous or less hazardous condition by raising the fluid to a supercritical state. This is accomplished by a rotatable mechanism having a reaction chamber adapted to receive the fluid and by rotating the rotatable mechanism at a high speed and by heating the fluid to cause the temperature and pressure of the fluid in the reaction chamber to reach the supercritical state.

Abstract: A method for treating polluted material such as industrial waste water or polluted water from other sources, sewage or sewage sludge, or other forms of sludge, to degrade oxidizable substances therein. The polluted material is subjected to a wet oxidation process in a tubular reactor so as to decompose and/or modify oxidizable substances therein and improve the filterability of any solids present in the material. The material may also be pretreated to facilitate the wet oxidation process. Solid polluted material is preferably in the form of an aqueous suspension when subjected to wet oxidation. The wet oxidation process is performed to such an extent that the decomposed and/or modified substances remaining after the oxidation step are substantially biodegradable. Heavy metals may also be removed subsequent to the wet oxidation process.

Abstract: A process is disclosed for co-processing spent nitric acid wash water with organic or biological wastes under wet oxidation conditions whereby the nitrogen content of the waste and the chemical oxygen demand and the nitrogen content of the nitric acid wash water and of the organic or biological wastes are significantly reduced. The nitric acid wash water is the waste stream generated by descaling wet oxidation reactors used for the treatment of organic or biological wastes, especially municipal wastes. The process of this invention can be carried out in conventional above ground equipment or in a subterranean, down-hole reactor having a vertical configuration which utilizes gravitational forces to provide a high pressure reaction environment. The nitric acid wash water and organic wastes are reacted with an oxidant at a temperature greater than 150.degree. C. and a pressure suffient to keep water in the liquid state.

Abstract: An organic or inorganic feed compound can be treated in two or more zones to progressively oxidize the compound. The first zone oxidizes the compound to an intermediate product which includes a first intermediate compound which is intermediate the feed compound and end product. The second zone further oxidizes the intermediate product to an end product or a second intermediate compound which is intermediate the first intermediate compound and an end product. One or both zones may operate catalytically and/or at supercritical conditions for water to oxidize the compounds.

Abstract: Disclosed is an apparatus and a process for high temperature water oxidation of combustibles in which during at least a part of the oxidation, corrosive material is present and makes contact with at least a portion of the apparatus over a contact area on the apparatus, wherein at least a portion of the contact surface area comprises a zirconia based ceramic, with the temperature of the oxidation process in excess of about 300.degree. C. and the pressure of the oxidation process is in excess of about 27.5 bar (400 psi).

Abstract: A pumpable aqueous slurry of sewage sludge as produced by the steps of (1) dewatering sewage sludge to produce an aqueous slurry having a solids content of about 10 to 25 wt. %; (2) pretreating said aqueous slurry of sewage sludge to improve its slurrying characteristics by one or a combination of (a) heating, (b) hydrothermal treatment, and (c) heating, mixing and shearing; and (3) mixing the following materials together at a temperature in the range of about ambient to 400.degree. F. to produce a pumpable aqueous slurry having a solids content in the range of about 30 to 65 wt. %: (a) pretreated aqueous slurry of sewage sludge; (b) a nonionic water soluble alkoxylated alkylphenol additive; and (c) sewage sludge-containing material and/or solid carbonaceous fuel-containing material to increase the solids loading.

Abstract: An improved process for oxidizing industrial spent caustic streams, whereby oxidation of spent caustic occurs in a unitary processing tower with three chambers that cooperate simultaneously to oxidize the caustic in the first chamber; to separate the caustic from the oxidizing gas in the second chamber; and, in the third chamber, to pass gas and cooled caustic through a mass transfer apparatus that cools and cleans the gas and releases the caustic and gas into a gas-liquid separation zone of the upper chamber. An alternative embodiment of the invention involves spatially separating the upper chamber from the other two chambers.

Abstract: A system for containment of a supercritical water oxidation reactor in the event of a rupture of the reactor. The system includes a containment for housing the reaction vessel and a communicating chamber for holding a volume of coolant, such as water. The coolant is recirculated and sprayed to entrain and cool any reactants that might have escaped from the reaction vessel. Baffles at the entrance to the chamber prevent the sprayed coolant from contacting the reaction vessel. An impact-absorbing layer is positioned between the vessel and the containment to at least partially absorb momentum of any fragments propelled by the rupturing vessel. Remote, quick-disconnecting fittings exterior to the containment, in cooperation with shut-off valves, enable the vessel to be isolated and the system safely taken off-line. Normally-closed orifices throughout the containment and chamber enable decontamination of interior surfaces when necessary.

Abstract: The present invention is a process for oxidation of a liquid which contains cyanide and soluble metal ions, using an oxygen-containing gas. Art example of such a liquid is the liquid waste produced during metal treatment processes. The disclosed process not only eliminates the cyanide completely, but also converts the metal dissolved in the liquid into granular metal oxides which can be readily recovered.

Abstract: A process for treatment of caustic sulfide liquor by wet oxidation in a ferrous-based alloy system at temperatures less than about 175.degree. C. is described. The liquor is first analyzed for alkalinity consuming species and for nonsulfidic alkalinity. If excess alkalinity consuming species is present compared to nonsulfidic alkalinity, then additional nonsulfidic alkalinity is added to the raw liquor such that excess alkalinity is present during wet oxidation treatment, thus preventing excessive corrosion to the ferrous-base alloy system.

Abstract: This is a process for wet oxidation of an ammonium salt containing waste liquor which prevents plugging of the vapor-carrying lines of the wet oxidation system. The vapor-carrying lines are maintained in an unobstructed condition by adding sufficient liquid water to dissolve condensed ammonium salt which can plug these lines. This provides for safe operation of the wet oxidation system.

Abstract: A method and apparatus is disclosed for oxidation of aqueous mixtures of organic material, including toxic material in the presence of inorganic materials, by reaction of said material with water and oxygen at supercritical conditions. Oxygen and the aqueous mixture are separately pressurized to greater than about 218 atmospheres, combined to form a reaction mixture and then directed through a tubular reactor having a substantially constant internal diameter. The velocity of the reaction mixture is sufficient to prevent settling of a substantial portion of solids initially present in the reaction mixture and of solids which form during passage through the reactor. The mixture is heated to temperature above about 374.degree. C. in the tubular reactor. A substantial portion of the organic material in the reaction mixture is oxidized in the tubular reactor to thereby form an effluent mixture.

Abstract: This invention relates to improved wet oxidation process for the destruction of organic components in a wastewater stream contaminated with inorganic salts. In wet oxidation, the wastewater stream is contacted with an oxygen-containing water stream at elevated temperatures and pressures. The improvement for treating aqueous wastewater streams contaminated with inorganic salts wherein the organic contaminants are present in an amount from about 0.5 to 2% by weight resides in oxidizing the organic components in a tubular reactor at a temperature ranging from 325.degree. C. to not more than 370.degree. C. and a pressure ranging from 220 to 345 bar. The oxidation reaction is carried out in a reaction time of 5 minutes or less.

Abstract: A process is provided for treating a sulfide-containing alkaline aqueous effluent to improve its environmental acceptability, which comprises: (a) intimately mixing a water-immiscible solvent, such as a pyrolysis gasoline, therewith for a sufficient time to extract polymerizable hydrocarbon compounds and/or other compounds which may cause fouling of downstream plant, (b) allowing the solvent phase and the aqueous phase to separate, (c) removing the solvent phase, and (d) subjecting the separated aqueous phase to an oxidation treatment which oxidizes sulfide ions to environmentally acceptable sulfur acid ions, particularly sulfate ions, e.g. a wet air oxidation process. The invention has been particularly developed for treating spent caustic which has been used to scrub gases produced by cracking for ethylene production. Such effluents have been found to cause fouling of the oxidation plant and the Applicants have found that this is due to polymerizable hydrocarbons.

Abstract: A two-stage wet oxidation process for COD removal from high strength wastewater is disclosed. The wastewater stream is treated in a first stage subcritical wet oxidation zone at temperatures between about 250.degree. and 374.degree. C. to remove a substantial portion of the COD. Subsequently, all or a portion of the first stage oxidized waste stream is treated in a second stage supercritical wet oxidation zone at temperatures of 374.degree. to about 600.degree. C. to remove any remaining COD content. Both stages of wet oxidation treatment are carried out at essentially the same system pressure.

Abstract: A process for removing undesired material from a chosen substrate by exposing the substrate simultaneously to ultraviolet radiation and a selected dense fluid, wherein the radiation produces a photochemical reaction that removes the undesired material from the substrate and the dense fluid enhances the removal of the undesired material. In an alternative embodiment, a reactive agent may additionally be used. The process may be used to remove contaminants from a substrate, etch a substrate surface, or destroy toxic organic material in industrial wastes.

Abstract: The invention is a process for starting up a wet oxidation system using essentially pure oxygen for oxidation of a concentrated wastewater. Flow of startup water and air is established through the wet oxidation system at an elevated temperature and pressure. An incremental increase in flow of oxygen and wastewater to the system commences while simultaneously an incremental decrease in flow of startup water and air occurs, raising system temperature in a controlled fashion. The incremental changes in flows are repeated until the wastewater and pure oxygen have reached about 100 percent of selected operating flows, the startup water and air flows have decreased to zero, and the system has attained the selected operating temperature, while maintaining a selected oxygen residual in the offgases.

Abstract: A process for breaking down aromatic nitro compounds in waste waters from plants for the production of nitrobenzene by treatment with nitric acid is carried out at from 180.degree. to 350.degree. C. and under a pressure of from 40 to 250 bar.

Abstract: Disclosed is a method of substantially completely oxidizing material in an aqueous phase at supercritical temperatures and sub- or supercritical pressures by initiating the oxidation in the presence of small amounts of strong oxidizing agents that function to increase the initial reaction rate for the oxidation. The strong oxidizing agents suitable for use in the present invention comprise at least one selected from the group consisting of ozone (O.sub.3), hydrogen peroxide (H.sub.2 O.sub.2), salts containing persulfate (S.sub.2 O.sub.8.sup.2-), salts containing permanganate (MnO.sub.4.sup.-), nitric acid (HNO.sub.3), salts containing nitrate (NO.sub.3.sup.-), oxyacids of chlorine and their corresponding salts, hypochlorous acid (HOCl), salts containing hypochlorite (OCl.sup.-), chlorous acid (HOClO), salts containing chlorite (ClO.sub.2.sup.-), chloric acid (HOClO.sub.2), salts containing chlorate (ClO.sub.3.sup.), perchloric acid (HOClO.sub.3), and salts containing perchlorate (ClO.sub.4.sup.-).

Abstract: A process for controlling corrosion in a wet oxidation system by controlling the operating pH range within the system is described. A pH operating range is selected within which corrosion to the wet oxidation system is minimized. The pH within the wet oxidation system is monitored and a pH adjusting material is added to the waste material being treated to maintain the system pH within the selected pH operating range, thus minimizing corrosion.

Abstract: A method is disclosed for denitrification of compounds containing nitrogen present in aqueous waste streams. The method comprises the steps of (1) identifying the types of nitrogen compounds present in a waste stream, (2) determining the concentrations of nitrogen compounds, (3) balancing oxidized and reduced form of nitrogen by adding a reactant, and (4) heating the mixture to a predetermined reaction temperature from about 300.degree. C. to about 600.degree. C., thereby resulting in less harmful nitrogen and oxygen gas, hydroxides, alcohols, and hydrocarbons.

Abstract: A method and apparatus for recovering energy from a wet oxidation products stream flow includes channeling the stream flow to an energy recovery assembly (10). The assembly (10) includes a rotatable reactor barrel (32). The reaction barrel (32) is mounted on an axle (33) for rotation therewith. The reaction barrel (32) has races (40) disposed in juxtaposition and circumferentially about the axle (33). Each race (40) is disk-like in shape, has an outer rim, and may be juxtapositioned adjacent to another race (40). The reactor barrel (32) is provided with a plurality of rocket nozzles (41) on each race (40), and rocket nozzles (41) on adjacent races (40) may be in staggered alignment with the rocket nozzles (41) of an adjacent race (40). The stream flow is channeled to and expelled through the rocket nozzles (41), thus causing the reactor barrel (32) to rotate. The stream flow may be channeled via nozzle ducts (52) having varying lengths to control the flow to the rocket nozzles (41).

Abstract: A process for disposing of sanitary sewage sludge by producing a pumpable slurry of sewage sludge with or without solid carbonaceous fuel and burning said slurry as fuel in a partial oxidation gas generator, furnace, or boiler. First, an aqueous slurry of sewage sludge is concentrated to produce sewage sludge cake. The sewage sludge cake is preheated and sheared while in contact with sulfuric or sulfurous acid to produce a pumpable acidified aqueous slurry of sewage sludge having a pH of about 1 to 5. After two-stage hydrothermal treatment with neutralization of the sewage sludge after the second hydrothermal stage, the solids content of the pumpable aqueous slurry of sewage sludge is increased. By means of the subject process, the viscosity of the slurry of sewage sludge with or without solid carbonaceous fuel is reduced and coagulation is suppressed.

Abstract: Processes for the regeneration of catalysts, such as hydrogenation catalysts, and the defouling of objects, which are contaminated with carbonaceous deposits. The catalyst or object is contacted with water, oxygen-containing gas, and at least one alkaline material maintained at a pH of at least 7.0, and at a temperature and pressure sufficient to combust at least a portion of the carbonaceous deposits. The process of the present invention enables one to remove carbonaceous deposits from catalysts or contaminated the leaching of metals from the catalysts or objects by acidic by-products of the combustion process.