Abstract: The present invention is directed to a method for recovering 2-chloropropionic acid so that this compound can be separated in a high-purity form. According to the method, crude 2-chloropropionic acid is heat-treated in the presence of a metal compound at a temperature in the range of 130.degree.-180.degree. C. where dichloro derivatives are contained as impurities or at a temperature not exceeding 160.degree. C. where no dichloro derivatives are contained. The metal compound is then removed at 160.degree. C. or lower. Final purification is thereafter conducted to obtain 2-chloropropionic acid as a high-purity product.

Abstract: In a supercritical oxidation process, the oxidized supercritical fluid effluent (46) discharged from the upper region of the reactor vessel (10) is contacted with a cold quench liquid (66) so as to produce a relatively solids free vapor stream (53) and a liquid stream (51) containing the bulk of the precipitates and other solids carried over in the oxidized supercritical fluid effluent (46). The temperature of the resultant liquid stream (51) is maintained at a temperature below the solids solubility inversion temperature, typically below 600.degree. F., so as to dissolve a substantial portion of the precipitates and other solids collected therein.

Abstract: A process is disclosed which limits the corrosion of the materials of construction of a wet oxidation system treating wastewaters. The process is particularly useful in the wet oxidation treatment of ammonium sulfate containing wastes such as acrylonitrile wastewaters. The wastewater is mixed with an oxygen containing gas such that a substantial residual oxygen gas concentration is maintained from before the stream-gas mixture is heated for wet oxidation until after the oxidized stream-gas mixture is cooled and separated. Preferably, in the treatment of acrylonitrile waste water the shutdown procedure comprises cooling said waste stream by introducing an aqueous liquid substantially free of organic impurities and containing a basic material.

Abstract: A process for treating an aqueous wastewater containing ammonium compounds. The process comprises the steps of preheating a liquid influent and introducing the preheated influent, an oxygen-containing gas an the wastewater into a reaction vessel for undergoing wet oxidation. An oxidized effluent is then withdrawn from the reaction vessel, which includes a gas phase containing ammonia and carbon dioxide and a liquid phase containing the ammonium compounds. The temperature of the effluent is then reduced to a temperature sufficient to condense a substantial portion of the ammonia into the liquid phase, and afterwards the remaining gas phase containing a substantial portion of the carbon dioxide is separated from the resulting liquid phase.

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 reaction barrel (32). The reaction barrel (32) is provided with a plurality of rocket nozzles (41). The stream flow is channeled to and expelled through the rocket nozzles (41), thus causing the reactor barrel (32) to rotate. Rotational energy is transferred from the reactor barrel (32) to a generator (43) where electrical power is produced.

Abstract: A process for destruction of hazardous materials in a medium of supercritical water without the addition of an oxidant material. The harzardous material is converted to simple compounds which are relatively benign or easily treatable to yield materials which can be discharged into the environment. Treatment agents may be added to the reactants in order to bind certain materials, such as chlorine, in the form of salts or to otherwise facilitate the destruction reactions.

Abstract: A process for removal of adsorbable organic chlorine (AOX) in which the acid-soluble AOX present in kraft chlorination (C.sub.D) effluents are destablized and converted to inorganic chloride by pH shift using the alkalinity and acidity sources available at the mill; C.sub.D effluent, typically having a pH of 1-2 and E.sub.1 effluent, typically having a pH of 9-12 can be mixed in various proportions to achieve a pH between 6.5-9.0 or the C.sub.D effluent is adjusted in pH to 6-11 with an alkaline composition so taht alkaline hydrolysis as well as precipitation of organic material occurs and the treated effluent contains less AOX than present in the original untreated effluents; the AOX removal is enhanced substantially by (i) the presence of a sulphide or (ii) by carrying out the alkaline treatment at elevated temperature and pressure.

Abstract: A method is disclosed for denitrification of nitrates and nitrates present in aqueous waste streams. The method comprises the steps of (1) identifying the concentration nitrates and nitrites present in a waste stream, (2) causing formate to be present in the waste stream, (3) heating the mixture to a predetermined reaction temperature from about 200.degree. C. to about 600.degree. C., and (4) holding the mixture and accumulating products at heated and pressurized conditions for a residence time, thereby resulting in nitrogen and carbon dioxide gas, and hydroxides, and reducing the level of nitrates and nitrites to below drinking water standards.

Abstract: Disclosed is a method of oxidizing materials in the presence of an oxidant and water at supercritical temperatures to obtain useful energy and/or more desirable materials. Pressures between 25 and 220 bar are employed. The use of appropriately high temperatures results in a single fluid phase reactor, rapid reaction rates, high efficiency oxidation, and precipitation of inorganic materials.

Abstract: A pressurized feed material (30) in aqueous suspension is oxidized in a supercritical temperature reaction zone (20) in an upper region of a vertically elongated, cyclindrical walled, closed pressure vessel (10) to form an oxidized super fluid phase (46) which is removed from the upper region of the vessel and a brine (44) containing precipitates and other solids which are collected in and removed from a subcritical temperature zone (16) in the lower region of the vessel. The wall (12) of the cylindrical pressure vessel (10) is scraped by rotatable scraper means (60) which upon rotation will dislodge precipitated solids from the wall (12).

Abstract: A process for treatment of caustic sulfide liquor by wet oxidation in a nickel-based alloy system 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 nickel-base alloy system.

Abstract: A process for removing PCDD's and PCDF's from paper mill sludge is provided. The process comprises combining the sludge with an oxidant and then oxidizing the sludge under supercritical or near supercritical conditions to destroy the PCDD's and PCDF's. Using this process, destruction efficiencies of greater than 98% have been achieved for 2,3,7,8-TCDD, which is reportedly the most toxic of the dioxins.

Abstract: A method for starting up and controlling the temperature of a wet oxidation process in which a heat exchanger employing superheated steam is used to initially heat a waste stream introduced into a wet oxidation reaction vessel for start up and then to subsequently adjust the temperature of the waste stream, after it is preheated by the effluent from the reaction vessel, to a level suitable to maintain steady state operation of the reaction vessel.

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, or polluted soil, to degrade oxidizable substances therein, comprising subjecting the polluted material to a wet oxidation process in a reactor so as to decompose and/or modify oxidizable substances therein and optionally improve the filterability of solids when present in the material; the material may optionally be pretreated so as to facilitate the wet oxidation process. Solid polluted material is preferably in the form of a liquid suspension, such as an aqueous suspension, when subjected to wet oxidation. The wet oxidation process is performed to such an extent, optionally with subsequent substantial removal of heavy metals, that the decomposed and/or modified substances remaining after the wet oxidation and the optional removal of heavy metals are substantially biodegradable.

Abstract: A process for effecting thermal decomposition of explosive nitric acid esters in wastewater effluents of the explosives industry wherein no additional by-products are produced and wherein the danger of explosions is avoided. In this process, the dissolved esters are exposed to a temperature of between 150.degree. and 300.degree. C. under pressure lying above the boiling pressure of the wastewater. During this step, the nitric acid esters are completely decomposed, and the wastewater treated in this way can then be passed on to further processing and purification. In a preferred embodiment, the hot wastewater exiting from a decomposer unit is exploited for preheating the effluent before it enters the decomposer unit.

Abstract: An apparatus is disclosed for improving the transportability of a hydrocarbon stream by reducing its viscosity. The apparatus comprises a reactor vessel useful for providing an incremental amount of heat to a hydrocarbon stream by the introduction of an oxidizing agent into the core portion of the stream. The reactor comprises an influent conduit and an effluent conduit in heat exchange relation with each other, at least one oxidant injection nozzle located in either or both the influent and/or effluent conduits, a conduit to transport oxidant to the nozzles and a valve in the oxidant conduit to control oxidant flow to the nozzles. The reactor can also contain temperature monitors in the influent and/or effluent conduits and an oxidant flow controller device responsive to output from the temperature monitors and adapted to adjust oxidant flow to maintain temperatures in the reactor reaction zone within a preselected range.

Abstract: Municipal sanitary sewage sludge is disposed of by an improved partial oxidation process without polluting the environment. Aqueous slurries of sewage sludge are upgraded by hydrothermal treatment, preferably while being sheared, concentrated, and then mixed with a supplemental fuel, preferably coal. A pumpable aqueous slurry of sewage sludge-coal and/or petroleum coke is thereby produced having a greater total solids and heat content (HHV) as well as containing an increased amount of sewage sludge for reacting with free-oxygen containing gas in a free-flow partial oxidation gas generator. Hot quench water or steam produced by cooling the hot raw effluent stream of synthesis gas, reducing gas or fuel gas from the gasifier may provide heat for the hydrothermal step.

Abstract: Municipal sanitary sewage sludge is disposed of by an improved partial oxidation process without polluting the environment. Aqueous slurries of sewage sludge are upgraded by being sheared without heating, concentrated if necessary, and then mixed with a supplemental fuel, preferably coal. In one embodiment, the aqueous slurry of sewage sludge and the supplemental coal and/or petroleum coke are introduced into a shearing mixer for simultaneous shearing and mixing together. A pumpable aqueous slurry of sewage sludge-coal and/or petroleum coke is thereby produced having an increased amount of total solids and an increased heat content (HHV) as well as containing an increased amount of sewage sludge for reacting with free-oxygen containing gas in a free-flow partial oxidation gas generator. Hot quench water or steam produced by cooling the hot raw effluent stream of synthesis gas, reducing gas or fuel gas from the gasifier may provide heat for indirect heat exchange with other streams in the process.

Abstract: The present invention provides a method and apparatus for collecting and liquefying off-gases, particularly carbon dioxide, generated by a wet oxidation of organic matter and for the on sight gasification of liquid oxygen for use as an oxidant in the wet oxidation reaction. Through a series of separation and pressurization operations, high pressure off-gases are introduced into a heat exchanger at substantially the same time as liquid oxygen. The liquid oxygen and compressed off-gases are in heat exchange relation in the heat exchanger but are isolated from one another. Heat is transferred from the compressed off-gases to the liquid oxygen whereby the off-gases are liquified and the liquid oxygen is gasified. The liquified off-gases may then be stored in appropriate storage units. The gaseous oxygen is used as the oxidant for the wet oxidation reaction.

Abstract: A method and apparatus for effecting accelerated chemical reactions at elevated temperatures and pressures including wet oxidation of materials in waste streams. An influent waste stream or first reactant is directed through a long tubular coil within a containment vessel with a second reactant being added to the influent. The flow rates for the gas and liquid components of the waste stream are set to cause plug or slug flow of the waste stream through the tubular coil. The curvature of the coil tends to induce a secondary flow in the liquid such that the liquid tends to travel in a spiral thereby providing more intimate mixing of the reactants; and the containment vessel may be partitioned to form a series of successive compartments to permit different temperature gradients to be applied to successive sections of the tubing coil across its length.

Abstract: The invention relates to a method for cleaning exhaust gases weak in sulphur dioxide, or sulphur dioxide and hydrogen sulphide. In order to remove the sulphur content of an exhaust gas, the exhaust gas is absorbed into a solution containing sulphide. Thereafter into the solution is added an agent which causes any unstable compounds of sulphur and oxygen, such as thiosulphate and polythionates, which are formed in the scrubbing solution, to decompose into elemental sulphur and sulphate in the autoclave whereinto the scrubbing solution is fed. The pH of the solution emerging from the autoclave is adjusted to stay within the range 2.0-2.9.

Abstract: Water contaminated with at least one volatile compound is treated by air stripping the volatile compound into the gas phase, then removing the volatile compound from the gas phase by contacting it with an aqueous mixture of biological solids and powdered adsorbent. The partially-purified water is further treated by a biophysical aerobic process which in turn produces the aqueous mixture of biological solids and powdered adsorbent used to remove the volatile compound from the gas phase. The aqueous mixture of biological solids and powdered adsorbent containing the volatile compound is thickened and the solids slurry treated by regeneration, preferrably wet air oxidation, to destroy the biological solids and volatile compound as well as regenerate the powdered adsorbent. The regenrated adsorbent may be returned to the biophysical aerobic treatment process.

Abstract: The process comprises injecting into the inlet of a polyphase tubular reactor (6), on one hand, the aqueous solution at such temperature that the oxidation reaction occurs at a temperature between 50.degree. C. and 370.degree. C. and at an absolute pressure Pe of between 2 bars and 210 bars, and, on the other hand, gaseous oxygen at a pressure slightly higher than said pressure Pe. The invention is applicable to the treatment of effluents for the chemical destruction of pollutants.

Abstract: The present invention relates to a novel aqueous-phase oxidizer and solids separator reactor. More particularly, the invention relates to a two zone pressure vessel in which precipitates and other solids fall or are sprayed from a supercritical temperature super zone into a lower temperature sub zone. The feed material may consist of various waste products which are subsequently oxidized in the super zone of the pressure vessel. The resultant brine or slurry which is found at the lower temperature sub zone of the vessel is removed via a pipe and disposed of accordingly.

Abstract: A method for operating a continuous wet oxidation system for destroying cyanide in caustic cyanide and metal wastes which scale upon heating. Raw waste is introduced into the wet oxidation reactor without heating while a mixture of heated dilution water and oxygen containing gas is introduced into the reactor by a separate inlet. The reactor is fitted with a pair of valved effluent lines and corresponding valved lines for introducing dilute mineral acid into each effluent line at system pressure. Oxidized effluent and offgases exit through a first effluent line while dilute mineral acid flows through a second effluent line into the reactor to prevent scale buildup. Periodically the flows are alternated such that oxidized effluent and offgases exit through the second effluent line and dilute mineral acid flows through the first effluent line into the reactor to remove scale. The oxidized effluent and offgases are then cooled and separated.

Abstract: A method for decomposing the cyanide radical in cyanide-bearing wastes or materials. The cyanide radical of cyanide compounds contained in cyanide-bearing wastes or materials is chemically decomposed. In the preferred embodiment, the cyanide-bearing waste or material and water are introduced into a closed retort. The closed retort is heated and maintained at a temperature above a critical temperature and the cyanide radical is decomposed by reaction with water. At least two new compounds are formed, one of which contains the carbon constituent and the other of which contains the nitrogen constituent of the cyanide radical. The gaseous components which form in the closed retort are vented therefrom and may be condensed. The nongaseous components which form in the closed retort are accumulated therein and removed periodically.

Abstract: An oxidative evaporation process for treating waste water or other aqueous solutions containing organics or reduced forms of inorganics is described. The process relies upon excessive amounts of pressurized oxygen gas to both oxidize the solution and to increase the solution's evaporation rate. The oxidized liquid effluent from a reactor undergoes a series of flashing steps until a saturated solution is produced which readily crystallizes upon cooling.

Abstract: A continuously flowing fluid is processed by being fed to the top of a hydraulic downdraft column (17) which is of a height such that the pressure at the bottom thereof will approximately be at the pressure necessary to create supercritical water conditions. The fluid is conducted to the bottom of the column (17) and received in a reaction chamber (21) in which the majority of the fluid is recirculated around an annular baffle plate (24). The material in the reaction chamber (21) is heated to a temperature above that necessary to create supercritical water conditions by an independent reaction taking place in a heating chamber (32). The result is that the fluid will undergo chemical reactions at the supercritical temperature and pressure range and will be of a lower specific gravity than the unprocessed fluid.

Abstract: The subterranean treatment apparatus and methods disclosed herein are useful for treating various waste streams, including municipal and industrial streams. The disclosed apparatus and methods are particularly useful in determining and controlling the temperature of the reaction zone in a deep well reaction apparatus while avoiding fouling of thermocouples and permitting easy service and replacement. In the disclosed embodiment, a fluid quiescent zone is created in the heat exchanger of the treatment apparatus located within the reaction zone and the temperature is used to control the system by operation of the heat exchanger or control of the C.O.D. of the influent.

Abstract: The present invention relates to an improved process for the wet oxidation of water soluble organic pollutants or of an aqueous suspension of organic pollutants. In the contacting of an oxidizing gas and a polluted aqueous phase, the improvement comprises forming a fine mist of the polluted aqueous phase in the presence of the oxidizing gas, thereby increasing the interfacial area between the gas and the polluted aqueous phase. Then the formed mist is introduced into a heated reaction chamber under pressure, thereby enhancing the rate of the destructive oxidation of the organic pollutant by the increase in mass transfer between the gaseous phase and the aqueous mist, the reaction temperature being selected to favor rapid destruction of the pollutant without the formation of stable intermediate reaction products. After destruction of the pollutants, the reaction mixture is allowed to flash off at a pressure lower than the reaction pressure.

Abstract: A method of treating organic waste is provided which includes separating the liquid portion of the waste from the solid portion prior to reacting said solid portion in an accelerated wet oxidation reaction. The method includes using an internally-derived ash from the wet oxidation reaction to weight the organic waste, thereby increasing the rate at which the liquid phase can be separated from the solid phase. By first removing the liquid portion of the waste, the oxygen demand of the waste to be processed by wet oxidation is substantially lowered. Ammonia is removed from the liquid portion of the waste in a de-ammoniating step which is followed by biological decomposition to form a liquid stream having a greatly reduced oxygen demand. In one embodiment, the method includes further treating the liquid stream to substantially remove salts and using the resulting deionized stream as a diluent to dilute the solid portion of the waste prior to wet oxidation.

Abstract: A wet, pressure, partial oxidation process to favor the partial oxidation of black liquor obtained from soda pulping. This is obtained by adjusting the equivalent of sodium ion content of a soda pulping black liquor within the range of about 21 to 26 weight % based on the total weight of the dissolved black liquor solids. This adjustment favorably reduces lignin fragments into short chain organic acids and thereby increases their production. In the case of potassium, the adjustment of the sodium content is carried out using an equivalent amount of a molar basis of potassium ion. A product wherein the amount of short chain organic acid salts is between 70 and 90%, the amount of aromatic lignin fragments and aromatic products thereof is between 0 and 10% and sodium carbon/bicarbonate mixture constitutes not more than 20% on the dry solids basis is also disclosed.

Abstract: The method of this invention is particularly, although not exclusively, adapted for effecting accelerated oxidation reactions in a downhole or deep well wet oxidation apparatus, including the processing of aqueous organic waste, such as municipal sludge. It includes injecting a multiple-phase composition which contains an oxygen or an oxygen-rich gas which is fully saturated with water vapor and which also contains water in the liquid phase into a wet oxidation reaction apparatus which contains an aqueous stream of combustible waste, preferably at the temperature and pressure of the waste stream at the point of injection. This reduces the likelihood of hazardous spontaneous combustion which may otherwise occur if dry spots are allowed to form in the reaction apparatus. The volume of water in the composition should be equal to at least twice the volume of water necessary to saturate the gas with water vapor to maintain at least 50 percent of the water in the liquid phase.

Abstract: A process for effecting chemical reactions, including wet oxidation reactions, in a deep well or down-hole reactor preferably providing a crosscurrent flow in a nested tube configuration wherein the influent fluid is in heat transfer relation with the effluent fluid. The disclosed process includes flowing an influent fluid including the reactants downwardly through a downcomer pipe which extends below ground in a subterranean opening or well casing forming a hydrostatic column of fluid, which defines a predetermined pressure, with the reactants at a temperature sufficient to initiate and maintain the desired chemical reaction. The method then includes flowing the effluent fluid upwardly through an upcomer pipe to ground level, preferably in heat transfer relation with the downflowing influent fluid. The method of this invention includes boiling the effluent fluid in the upcomer pipe, thereby reducing the hydrostatic fluid pressure in the upcomer and increasing the mass flow rate.

Abstract: The heat exchanger, which forms a part of the fluid treatment apparatus of this invention, includes an insulated tubular having concentric telescopically nested spaced tubes, wherein the space between the tubes is sealed and filled with an inert gas. The surfaces of the tubes are coated with a hydrogen permeation barrier preferably comprising an aluminum-iron alloy, nickel or copper which limits atomic hydrogen permeation into the space between the tubes, which would combine to form hydrogen gas and result in heat loss. The insulated tubular is telescopically nested in a pipe, forming a fluid heat exchanger and the heat exchanger is telescopically nested in fluid waste circulation pipes, forming the fluid treatment apparatus of this invention. The preferred fluid heat exchanger is a vertically extending deep well reactor suitable for wet oxidation reaction of fluid wastes including municipal sludge.

Abstract: A method and apparatus for effecting accelerated chemical reactions at elevated temperatures and pressures including wet oxidation of materials in waste streams. An influent waste stream or first reactant is directed through a long tubular coil within a containment vessel with a second reactant being added to the influent. The waste stream includes gas and liquid components. The flow rates for the reactants of the waste stream are set to cause plug or slug flow of the waste stream through the tubular coil. The curvature of the coil tends to induce a secondary flow in the liquid component such that the liquid component tends to travel in a spiral thereby providing more intimate mixing of the reactants. The containment vessel may be partitioned to form a series of successive compartments to permit different temperature gradients to be applied to successive sections of the tubing coil across its length.

Abstract: A process for reducing calcium, magnesium and aluminum salt scale build-up in continuous flow or plug flow tube reactors in which a fluid waste undergoes a chemical reaction under heat and pressure to form more environmentally desirable compounds. The process includes the injection of a precipitating reagent into the influent path of a fluid waste stream in a tube reactor to preferentially precipitate calcium, magnesium and aluminum ions which are then carried through and out of the reaction apparatus in a non-scale forming suspension.

Abstract: A method of removing scale from the surfaces of a fluid treatment apparatus by directing a base solution and an acid solution through the fluid treatment apparatus. The fluid treatment apparatus cleaned by the method of the present invention is a vertical tube wet oxidation treatment apparatus in which an aqueous slurry of organic materials is oxidized in a tube which extends deep into the surface of the earth. Water rinses are performed between the steps of circulating the aqueous base solution, circulating the aqueous acid solution, and operating the fluid treatment apparatus. The water used for separating the sequential steps is preferably buffered water. The aqueous acid solution is preferably a mineral acid and most preferably nitric acid. The aqueous base solution is preferably potassium hydroxide or sodium hydroxide. The method also contemplates a sectional wash of the apparatus by directing a base or acid solution partially into the apparatus.

Abstract: The heat exchanger, which forms a part of the fluid treatment apparatus of this invention, includes an insulated tubular having concentric telescopically nested spaced tubes, wherein the space between the tubes is sealed and filled with an inert gas. The surfaces of the tubes are coated with a hydrogen permeation barrier preferably comprising an aluminum-iron alloy, nickel or copper which limits atomic hydrogen permeation into the space between the tubes, which would combine to form hydrogen gas and result in heat loss. The insulated tubular is telescopically nested in a pipe, forming a fluid heat exchanger and the heat exchanger is telescopically nested in fluid waste circulation pipes, forming the fluid treatment apparatus of this invention. The preferred fluid heat exchanger is a vertically extending deep well reactor suitable for wet oxidation reaction of fluid wastes including municipal sludge.

Abstract: A wet air oxidation process for oxidizing organic matter dispersed in a liquid fuel stream at controlled high temperatures and pressures is capable of treating concentrations of organic matter in the feed stream far in excess of concentrations of organic matter treated in the normal type of wet air oxidation process. The improvement in the process is in the provision of a vapor phase effluent from the reactor system which is considerably greater than normal due to the introduction of high volumes of the oxidizing gas. This provides for increased concentrations of organic matter in the feed stream; however, resulting in the generation of excess energy within the reactor system which cannot be removed in the vapor and liquid phase effluents from the reactor system.

Abstract: An improved process for the wet oxidation of malodorous gases obtained from sewage sludge drying operations is provided. Organic-enriched water having an oxygen demand of at least 5 mg per liter is utilized for the process.

Abstract: This invention comprises a wet oxidation process utilizing copper (II) oxide as the sole oxygen source. In particular the destruction and detoxification by oxidation of toxic materials such as cyanide, hydrocarbons, halogenated hydrocarbons, and dioxins contained in typically aqueous streams by using copper (II) oxide is contemplated. The preferred embodiment involves adding the copper (II) oxide to the feed stream containing the toxic materials and reacting the stream under elevated pressure and elevated temperature conditions to substantially oxidize the toxic materials to less toxic or innocuous compounds. The oxidation process can be accomplished in a vertical tube reactor system, wherein the necessary pressure for the wet oxidation is achieved by hydrostatic head pressure inherent in the system.

Abstract: A process for reducing the water content of coal containing bound water by treating the coal at an elevated temperature and pressure in a de-watering zone in the presence of liquid water to remove liquid water from the coal and treating liquid water in the de-watering zone or liquid water removed from the coal or both by a wet air oxidation process.

Abstract: In the preferred and illustrated embodiment, a deep well is utilized to form a reaction chamber for combustible waste in water. A stream of water borne combustible waste is delivered into a deep well, sufficiently deep to obtain a pressure and temperature in a bottom located reaction chamber at which the water becomes supercritical, there being a pipe for delivering oxygen under pressure for combusting oxygen dissolved in the supercritical water with the waste materials. The reaction is exothermic to sustain itself. It is started preferably by electric current flow to initially raise the temperature in the reaction chamber. The preferred structure is a cased abandoned well having a surrounding cement bond to the formation thereby retarding heat loss into the formation, the bottom located reaction chamber sustaining supercritical conditions.

Abstract: Hazardous waste containing organic compound having covalently bound oxygen, nitrogen, sulfur and/or phosphorus is reduced with aluminum to less hazardous form.

Abstract: A method of oxidizing an organic material in an oxidizer includes forming a mixture of the organic material with water and a fluid including oxygen under conditions near supercritical pressure. At the inlet of the oxidizer, the mixture is caused to undergo reaction under supercritical conditions for water, characterized by a temperature of at least about 400.degree. C. and a pressure of at least about 220 atmospheres in the oxidizer.

Abstract: A method is disclosed for removing phosphates from deproteinized cheese whey to improve the handling characteristics of such deproteinized whey. The method includes adjusting the pH of the deproteinized whey, a heating step subsequent to pH adjustment followed by injection of calcium hydroxide to remove dicalcium phosphate as a precipitate. Following a holding period, the precipitate is removed to yield an improved deproteinized whey.

Abstract: A method comprising operating steps required for safely operating wet oxidation reactors in which combustible substances are oxidized at elevated temperatures and pressures using pure oxygen. The steps satisfy the criteria that a potential of oxidation is established prior to introducing oxygen and maintained until after oxygen flow is stopped; that an inert gas, either from an external source or generated in situ, is present in the reactor from before oxygen flow is introduced until after oxygen flow is stopped; and that the oxygen introducing means is clean for oxygen use from prior to the introduction of oxygen flow until after the oxygen flow is stopped.

Abstract: A continuous process for wet oxidation of aqueous liquor containing combustible matter using oxygen or oxygen enriched gas. An inert diluent gas is injected into the aqueous liquor or reactor off-gas such that oxygen in the gas phase is diluted by the sum of generated water vapor, produced carbon dioxide and injected inert gas to a concentration less than required for spontaneous combustion at every location in the system having surfaces not continually exposed to a continuous liquid water phase.

Abstract: A process and apparatus for treating thiosulfate containing liquors such as coke oven gas scrubbing liquors in two stages of wet oxidation with intermediate removal of elemental sulfur. Mild oxidation conditions in the first stage results in conversion of thiosulfate sulfur to elemental sulfur, which is removed prior to second stage wet oxidation of the liquors to substantially reduce the liquor oxygen demand.