Abstract: An improved cleaning system is provided for removing impurities from a material to be cleaned. The system includes two electrodes, a positive electrode ("anode") on one side, near to or in contact with the material to be cleaned, and a negative collector electrode ("cathode") located at a distance from the second side of the material. The material and the two electrodes are placed into a chamber. The system also includes a medium of conductivity which, when under voltage between anode and cathode, produces the flow of negative charge either as electrons or as negative ions. The chamber may be a vacuum chamber or a chamber filled with an inert gas or other electro-negative gases. The flow of negative charges provides layer of negative charge near the second surface of the material so as to induce the positive impurity ions to move towards the surface. Since a grid electrode is absent, the impure ions are removed unhindered from the material to be cleaned.

Abstract: A post-etch treatment method capable of imparting high corrosion prevention performance to the aluminum-containing wiring films. The sample of aluminum-containing wiring material that is etched using the halogen-type gas is treated with the plasma of a gas that has the oxygen component, and the resist formed on the aluminum-containing wiring material is reacted with oxygen and is removed. Further, the plasma is generated using a gas having the hydrogen component or this gas is liquefied into droplets thereof on the sample surface, so that halogen components (Cl, Br, etc.) adhered to the aluminum-containing wiring material through the etching treatment are reacted with hydrogen and are effectively removed in the form of hydrogen chloride (HCl) or hydrogen bromide (HBr). This makes it possible to obtain the aluminum-containing wiring material having high corrosion prevention performance.

Abstract: A process for recovering organic solvent material from a hydrophilic liquid derived from paint overspray treatment operations in which the solvent-in-water emulsion initially contains 1-50 weight percent of an organic liquid having a boiling point of at least 150.degree. C., a vapor pressure less than 0.5 Torr at 20.degree. C.; and water, and the spent hydrophilic liquid additionally contains paint solid material derived from the paint overspray treatment system in which the recovery process includes the steps of(a) removing the spent hydrophilic liquid or a portion thereof from the paint spray booth;(b) feeding the spent hydrophilic liquid into a reaction vessel, the reaction vessel operating at a pressure less than about 100 mm/Hg and at a temperature sufficient to volatilize the organic liquid component of the hydrophilic liquid; and(c) separating a portion of said volatilized organic liquid from the spent hydrophilic liquid after introduction of the spent hydrophilic liquid into the reaction vessel.

Abstract: A method for achieving greater uniformity and control in vapor phase etching of silicon, silicon oxide layers and related materials associated with wafers used for semiconductor devices comprises the steps of first cleaning the wafer surface to remove organics, followed by vapor phase etching. An integrated apparatus for cleaning organic and, subsequently, vapor phase etching, is also described.In embodiments of the invention cooling steps are incorporated to increase throughput, an on-demand vaporizer is provided to repeatably supply vapor at other than azeotropic concentration, and a residue-free etch process is provided.

Abstract: A plasma etching process for cleaning laterally exposed p-n junctions of semiconductor elements, in particular power diodes after soldering together the semiconductor chip in question and connection elements is proposed, wherein the etching gases employed are fluorine compounds. Since the process according to the present invention does not involve doping dependence and crystal orientation dependence, it produces essentially vertically oriented chip-edges after etching and as a result a lower failure rate compared to the known wet-etching process. Since numerous rinsing processes can also be dispensed with, the plasma etching process is more suitable for mass production.

Abstract: An improved process is described for the post-etching treatment after subtractive etching of aluminum and aluminum-alloy layers in the fabrication of semiconductor integrated circuit devices. The improvement consists of in situ exposure immediately after subtractive etching of the metal pattern to a reactive plasma sustained in a mixture of oxygen and carbon tetrafluoride gases by continuous radiofrequency power input for a controlled period of time.

Abstract: A method of cleaning an electrostatic chuck of a plasma etching apparatus wherein a dummy wafer is placed on the chuck, the chamber evacuated, and an RF voltage applied that is greater than the normal RF voltage used to etch.

Abstract: A method for drying parts that includes contacting the part with a liquid removing composition that contains a straight chain or cyclic polyorganosiloxane.

Abstract: Method and apparatus for recycling a water-displacement process fluid that includes an organic liquid and a surfactant, the boiling point of which exceeds that of the organic liquid, maintains a sufficient quantity of organic liquid such that water displaced into the organic liquid is evaporated at least as fast as it is introduced. If the water and the organic liquid are immiscible and exhibit different densities, the resulting condensate can be separated into constituent phases by decanting. The condensed organic liquid and unevaporated surfactant are then available for recycling.

Abstract: A method for cleaning an industrial object by use of an aqueous agent that includes a polyorganosiloxane. The method uses a plurality of vessels and the agent is recovered and resupplied to the method.

Abstract: The present invention provides a method to separate and recover oils and recyclable plastic from plastic contaminated with oil. The invention utilizes the different solubility of oil in as liquid or supercritical fluid as compared to a gas to effect separation of the oil from the plastic.

Abstract: Clothes are dry cleaned by placing the clothes in a tumbler/dryer, sealing the tumbler/dryer, applying a negative gauge pressure to the tumbler/dryer, providing solvent to the tumbler/dryer, activating the tumbler/dryer to dry clean the clothes, removing the solvent from the tumbler/dryer, and simultaneously throttling hot solvent vapor into the tumbler/dryer while removing vapor from the tumbler/dryer in order to dry the clothes.

Abstract: A method for limiting contaminant particle deposition upon integrated circuit layers within plasma assisted process reactor chambers. First, there is undertaken a plasma assisted process upon an integrated circuit layer within a plasma assisted process reactor chamber. The plasma assisted process employs a reactant gas composition, a first radio frequency power and a first reactor chamber pressure appropriate to the plasma assisted process and the integrated circuit layer. There is then undertaken a first plasma purge step for a first purge time immediately following the plasma assisted process. The first plasma purge step employs a first purge gas composition, a second radio frequency power and a second reactor chamber pressure. The second radio frequency power is lower than the first radio frequency power and the second reactor chamber pressure is higher than the first reactor chamber pressure.

Abstract: The present invention is directed to a method of removing polymer residue from chemical processing equipment, comprising contacting said residue with NMP vapors.

Abstract: A wafer (11) is conveyed in a vacuum from an Al etching chamber after the Al etching and is fed into an ashing chamber (15) without coming into contact with the atmosphere. After the wafer (11) was conveyed, CH.sub.3 OH gas of 200 sccm is first introduced by a valve (30a) and a pressure is adjusted to 1.2 Torr. Subsequently, a microwave current of 450 mA is supplied, thereby forming a plasma. The wafer (11) is processed by a down-flow system of a CH.sub.3 OH plasma. The supply of the CH.sub.3 OH gas is stopped by closing the valve (30a). Next, oxygen gas of 400 sccm is introduced by opening a valve (30b). A microwave current of 450 mA is supplied at a pressure of 1.2 Torr, thereby forming a plasma. A resist on the wafer 11 is ashed and eliminated by a down-flow process of an oxygen plasma. By those processes, the corrosion prevention and the resist ashing can be perfectly executed.

Abstract: A barrier discharge device (4a, 4b, 4c) installed in a vacuum chamber (1) consists essentially of at least two facing electrodes (20, 22); a dielectric (22) situated between the electrodes (20, 22) and in the immediate proximity of one of these electrodes (20); and a power source (26), which is connected electrically to the electrodes (20, 22). The plasma particles and UV radiation generated during the electrical discharge between the electrodes (20, 22) pass through the electrode (22), which is permeable to UV radiation and plasma particles, and thus emerge from the discharge space. On the surfaces (5a, 5b), the UV radiation induces a photochemical cleaning process, and the impinging plasma particles induce a plasma-chemical cleaning process. The cleaning process is essentially independent of pressure and can be used at pressures of up to 10 bars, which means that the cleaning process can be operated in particular during the time in which the vacuum chamber (1) is being pumped out.

Abstract: A method of reducing carbon incorporation into films is disclosed which comprises the steps of depositing a layer on a substrate by CVD using organic precursors, the layer comprising hydrocarbons or carbides; and utlizing a reactive hydrogen plasma to displace the hydrocarbons or carbides away from the layer.

Abstract: Novel azeotrope-like compositions of 1,1,1,3,3-pentafluoropropane and C.sub.1 -C.sub.3 alcohols or mixtures thereof are useful in solvent cleaning.

Abstract: The plasma dry cleaning rate of semiconductor process chamber walls can be improved by placing a non-gaseous dry cleaning enhancement material in the position which was occupied by the workpiece during semiconductor processing. The non-gaseous dry cleaning enhancement material is either capable generating dry cleaning reactive species and/or of reducing the consumption of the dry cleaning reactive species generated from the plasma gas feed to the process chamber.When process chamber non-volatile contaminant deposits are removed from plasma process chamber surfaces during plasma dry cleaning by placing a non-gaseous source of reactive-species-generating material within the plasma process chamber, the non-gaseous source of reactive-species-generating material need not be located upon or adjacent the workpiece support platform: however, this location provides excellent cleaning results in typical process chamber designs.

Abstract: A method for removing particulate residues from semiconductor substrates. A semiconductor substrate is provided which has upon its surface a particulate residue. At minimum, either the semiconductor substrate or the particulate residue is susceptible to oxidation upon exposure to an oxygen containing plasma. The semiconductor substrate and the particulate residue are exposed to an oxygen plasma. The particulates are then rinsed from the surface of the semiconductor substrate with deionized water.

Abstract: A method of cleaning a substrate surface, the cleaning being done photoreactively without damaging the surface. A laser beam of UV radiation is delivered at an acute angle to the surface of the substrate, the beam striking the surface at a long and narrow reaction region. The beam and the substrate are moved relative to one another to cause the beam to sweep the surface. While the beam is sweeping the surface, a flow of a reactant gas is provided at the reaction region so that the gas is excited by the UV laser beam. The acute angle of the beam is of a value such that foreign material is removed without essentially damaging the surface of the substrate or leaving a residue that would inhibit further processing of the substrate surface.

Abstract: A cleaning solvent composition that is made by either blending aliphatic fluorohydrocarbon as expressed by the general formulaC.sub.n F.sub.m H.sub.2n+2-m(wherein, n and m are a positive integral numbers, being 4.ltoreq.n.ltoreq.6, 2n-3.ltoreq.m<2n+2 respectively) or blending a mixture of this aliphatic fluorohydrocarbon and alcohol having a carbon number of 1 to 4 with lactam and/or carboxylic acid amide, tertiary amines, or alcohol having ether linkage and/or amino linkage within its molecules. A cleaning process wherein an object is dipped into the said composition to remove dirty component, then rinsed with a mixture of the said aliphatic fluorohydrocarbon and the said alcohol having a carbon number of 1 to 4, and thereafter the object is steam cleaned with the said mixture when necessity arises.

Abstract: A method of removing material from an integrated circuit. The integrated circuit is placed within a reaction chamber, and a flow of argon and a flow of hydrogen are introduced into the reaction chamber, where the flow of hydrogen is greater than the flow of argon. The flows of argon and hydrogen are energized to form a plasma, and the material is removed from the integrated circuit by reaction of the material with the energized flows of argon and hydrogen to form gaseous products, which are pumped out of the reaction chamber. The plasma and flows of argon and hydrogen are discontinued when a desired amount of material has been removed, and the integrated circuit is removed from the reaction chamber.

Abstract: A chemical vapor reaction processing apparatus including a reaction chamber; a power source; a source of a reactive film forming gas; a device for inputting the reactive film forming gas into the chamber; a pair of electrodes connected to the power source, at least a portion of the pair of electrodes being provided in the reaction chamber; a power source for supplying a first electric power into the reaction chamber through the pair of electrodes to generate a plasma of the reactive film forming gas in the chamber for providing a plasma CVD deposition of the reactive film forming gas on a surface; a source of a reactive cleaning gas; a device for inputting the reactive cleaning gas into the chamber where the power source supplies a second electric power into the reaction chamber through the pair of electrodes to generate a plasma of the reactive cleaning gas in the chamber so that an inner wall of the chamber is cleaned by the plasma.

Abstract: A method for limiting contaminant particle deposition upon integrated circuit layers within plasma assisted process reactor chambers. First, a plasma assisted process is undertaken upon an integrated circuit layer within a plasma assisted process reactor chamber. The plasma assisted process employs a first reactant gas composition, a first radio frequency power and a first reactor chamber pressure appropriate to the plasma assisted process and the integrated circuit layer. Immediately following the plasma assisted process is undertaken a first plasma purge step. The first plasma purge step employs a first concentration of an oxidizing reactant gas, a first concentration of a non-oxidizing reactant gas, a second radio frequency power and a second reactor chamber pressure. The second radio frequency power is lower than the first radio frequency power and the second reactor chamber pressure is higher than the first reactor chamber pressure.

Abstract: An apparatus and method for removing hydrocarbons from soil is disclosed. A gradient force machine pulverizes contaminated soils, which are then mixed with release agents in a mixing tank. A water-filled separation unit receives the mixed soil, the unit having a plurality of counter-rotating augers to aid in the breakdown of the mixed soil to solid, water and hydrocarbon components. A washing container receives the solid component from the separation unit, the container having a diagonally-disposed, enclosed auger for outputting a washed solid component. Hydrocarbons that have floated to the top of the separation unit and washing container are removed by a vacuum system.

Abstract: A method is disclosed for using the simple, environmentally friendly organic compounds gamma-butyrolactone and benzyl alcohol to develop and to strip free radical-initiated, addition polymerizable resists, cationically cured resists and solder masks and Vacrel photoresists. In all cases the developers and strippers include gamma butyrolactone or benzyl alcohol. The developers and strippers optionally also include a minor amount of methanol, ethanol, isopropyl alcohol, propylene glycol monomethylacetate, ethylene glycol monomethyl ether, formamide, nitromethane, propylene oxide, or methyl ethyl ketone, acetone and water. During development of the photopatterned resist or solder mask, the unpolymerized regions are dissolved in the disclosed developers. During stripping of the resist or solder mask, the polymerized regions are debonded from a circuit board in the disclosed strippers.

Abstract: A method of recycling and purifying cleaning chemicals used in the production of semiconductor circuits and containing hydrofluoric acid and or hydrochloric acid. Recycling of such chemicals is accomplished using separation and reconstitution steps Hydrofluoric acid and hydrochloric acid cannot be distilled directly from a chemical solution as they form azeotropes with water. A low vapor pressure substance such as sulfuric acid or phosphoric acid is used to break the azeotrope while increasing the purity of the recovered chemicals and decreasing disposal problems. The method is useable at the point of use of the chemicals.

Abstract: The present invention is directed to the etching of a material selected from the group consisting of silicon dioxide, silicon nitride, boronphosphorus silicate glass, fluorosilicate glass, siliconoxynitride, tungsten, tungsten silicide and mixtures thereof under plasma etch conditions, particularly for cleaning operations to remove silicon dioxide or silicon nitride from the walls and other surfaces within a reaction chamber of a plasma-enhanced chemical vapor deposition reactor. The etching chemicals used in the etch process are trifluoroacetic acid and it derivatives, such as; trifluoroacetic anhydride, trifluoromethyl ester of trifluoroacetic acid and trifluoroacetic acid amide and mixtures thereof.

Abstract: Contaminant particles in a vacuum plasma processing chamber can be removed from the surface of a substrate in the chamber by first reducing the pressure in the chamber so as to elevate the particles above any obstruction about the substrate, including a clamping ring and the like, maintaining a plasma from a gas fed to the chamber so that the particles are in the plasma, and then increasing the gas flow to the chamber so as to sweep the particles out of the chamber through the exhaust system of the processing chamber while maintaining a plasma in the chamber.

Abstract: Stable azeotrope-like compositions consisting essentially of dichloropentafluoropropane and a hydrocarbon containing six carbon atoms which are useful in a variety of industrial cleaning applications including cold cleaning and defluxing of printed circuit boards.

Abstract: A vacuum processing apparatus includes a plurality of vacuum processing chambers for processing a target object using a process gas, a vacuum convey chamber, connected to the plurality of vacuum processing chambers, for loading/unloading the target object into/from the processing chambers, an opening/closing means opened/closed to cause the plurality of vacuum processing chambers to communicate with the vacuum convey chamber, and a cleaning gas supply means for supplying a cleaning gas containing ClF.sub.3 into at least one of the vacuum convey chamber and the plurality of vacuum processing chambers. The cleaning gas is supplied-into the plurality of vacuum processing chambers and the vacuum convey chamber communicating with each other by opening the opening/closing means to clean the plurality of vacuum processing chambers and the vacuum convey chamber.

Abstract: The present invention provides a solvent mixture comprising n-Propyl bromide, a mixture of terpenes and a mixture of low boiling solvents, and a method for cleaning an article (e.g., an electrical, plastic, and metal parts) in a vapor degreaser using the solvent mixture. The solvent mixture of the present invention is non-flammable, noncorrosive and non-hazardous. In addition, it has a high solvency and a very low ozone depleting potential. Thus, using the solvent mixture of the present invention, oil, grease, rosin flux and other organic material can be readily removed from the article of interest in an environmentally safe manner.

Abstract: The cleaning apparatus of the present invention is composed of a cleaning chamber 1 of vacuum-tight structure in which a work W to be cleaned is contained, an organic solvent vapor generating tank 4 communicated with the cleaning chamber 1 via piping, and a vacuum pump 6 for evacuating the cleaning chamber 1. A heat exchange member 3 through which a cooling medium passes is provided upside in the cleaning chamber 1. After the cleaning chamber 1 is reduced in pressure, the cooling medium is supplied into the heat exchange member 3 while organic solvent vapor is introduced from the vapor generating tank 4 into the cleaning chamber 1. Thus, a cleaning process is executed in combination of vapor cleaning by the vapor condensing on the surface of a work W and shower cleaning by the vapor being liquefied by the heat exchange member 3 and dropping onto the work W.

Abstract: A process for the use of organic chlorides having the general formula C.sub.x H.sub.y Cl.sub.y, C.sub.z Cl.sub.s, C.sub.r O.sub.u Cl.sub.2(r-u+1), C.sub.r O.sub.u Cl.sub.r-u+1 H.sub.r-u+1, wherein x=1-10, more preferably 1-6; y=x+1, x or x-1; z=1-10, more preferably 1-6; s=2(x+1, x or x-1), r=1-10, more preferably 2-4; u=1, 2 and up to r, as precursors for decomposition to chlorine and oxygen-containing reactive reagents for subsequent use for vapor cleaning of silicon, thermal oxidation of silicon in a range of 200.degree. C.-1200.degree. C., rapid thermal oxidation of silicon and silicon polishing or etching.

Abstract: A metal structure, such as an apparatus used in plasma processing of substrates, is rendered resistant to corrosion by coating components exposed to the plasma with a coating of rhodium. The rhodium coating can be made by electroplating, and preferably has a thickness of at least about 10 microinches, and preferably from about 10 to about 100 microinches. A coating of nickel can be applied between the rhodium coating and the metal component.

Abstract: Azeotropic or azeotrope-like compositions of effective amounts of 1,1,1,2,3,4,4,5,5,5-decafluoropentane, heptane and an alcohol such as methanol, ethanol, n-propanol or isopropanol, to form an azeotropic or azeotrope-like composition are disclosed that are useful as cleaning agents, refrigerants, aerosol propellants, heat transfer media, gaseous dielectrics, fire extinguishing agents, expansion agents for polyolefins and polyurethanes and as power cycle working fluids.

Abstract: An apparatus for subjecting a semiconductor wafer having an uncovered marginal portion, from which a photoresist film is removed, to an anisotropic etching. The apparatus comprises a process chamber which can be set to a vacuum. Upper and lower electrodes opposite to each other are provided in the process chamber. An etching gas is made into plasma between these electrodes. An electrostatic chuck is arranged on the lower electrode. A wafer is mounted on the electrostatic chuck. A ring made of dielectric material, movable upward and downward, is arranged between the electrodes. A central portion of the ring is formed as a hood having a recessed shape corresponding to the marginal portion of the wafer. During the etching, the hood covers the marginal portion of the wafer under a plasma sheath, so as to be out of contact with the wafer, thereby preventing the marginal portion of the wafer from being etched.

Abstract: A Reactive Ion Etch (RIE) plasma method for removing from semiconductor substrates oxidized organic residues such as oxidized photoresist residues, and the Reactive Ion Etch (RIE) plasma which is employed within the Reactive Ion Etch (RIE) plasma method. A semiconductor substrate upon whose surface resides an oxidized organic residue such as an oxidized photoresist residue is provided into a Reactive Ion Etch (RIE) plasma chamber. Also provided into the chamber is a concentration of oxygen and a concentration of moisture. Finally, a radio frequency excitation of sufficient magnitude is provided to the concentration of oxygen and the concentration of moisture to form a plasma. The oxidized organic residue which resides upon the semiconductor substrate is then removed through etching in the Reactive Ion Etch (RIE) plasma.

Abstract: A gas discharge through nitrous oxide or nitrogen is used to remove polymeric deposits that form on the surface of a layer of a spin-on glass that was etched in an atmosphere of carbon-fluorine compounds. Removal of the polymeric deposit greatly improves adhesion to the spin-on glass layer of subsequently deposited layers. The removal is accomplished without increasing any tendency of the spin-on glass layer to absorb moisture.

Abstract: A method for recovering solvent vapor in a manner which requires less power using an apparatus which is smaller in size, has a longer life, and is capable of being operated without reducing recovering efficiency, including locating an inlet of a suction pipe at a position within the container between the liquid surface of the solvent and an upper edge of the container, wherein the opening of the suction pipe is open downward, and drawing the vapor from the upper surface of the solvent in the container.

Abstract: A method for the removal of halogenated organic contaminants from particulate material by admixing an additive selected from the group consisting of a sodium salt and an ammonium salt with the particulate material, and passing a vapor phase of steam through the material to substantially remove the halogenated organic contaminant.

Abstract: A method and system for removing a surface layer contaminated with radioactive and/or hazardous material and subsequently treating the waste to remove contaminants and provide an essentially contaminant-free final effluent. The contaminated material is removed by blasting the surface with a pressurized stream of air and sodium bicarbonate abrasive media, and the media is dissolved in water subsequent to the blasing operation. The resulting waste is treated in a sequence of steps including adjustment of pH, aeration and separation into primarily solid and liquid phases by precipitation of solids, which are removed for appropriate disposal. The primarily liquid phase is successively passed through a particle filter, a granulated activated carbon filter and a polishing unit to produce the clean final effluent.

Abstract: Soil including sand and clays contaminated with elemental mercury are decontaminated by forming slurries with anhydrous liquid ammonia. An ammoniacal liquid, such as anhydrous liquid ammonia facilitates decontamination by breaking up soil into fine slurries for releasing droplets of mercury metal. The high density of the mercury metal permits precipitation with larger soil particles and for recovery from soil particulates. Contaminated soils having mixed wastes comprising metallic mercury with organic compounds like PCBs are decontaminated first by slurring with anhydrous liquid ammonia to release droplets of mercury for coalescing and recovery. Solvated electrons are formed in the slurry in-situ by treating the slurry with an alkali metal or alkaline earth metal to reduce or degrade toxic organic compounds to more environmentally benign substances.

Abstract: In preparation for removing a protective adherent covercoat from a circuit board that is to be repaired, the surface integrity of the coating is altered (for example, by making incisions therein). Subsequently, the coated circuit board is subjected to supercritical carbon dioxide in a processing chamber. Following this process, the coating is easily lifted from the board.

Abstract: The characteristics of a Schottky junction between diamond and metal causes the diode using the Schottky junction to have a large leakage reverse current and n-value far bigger than 1. A surface of diamond on which a Schottky junction shall be formed is pretreated by oxygen plasma or halogen plasma. The oxygen plasma or hydrogen plasma improves the surface state of the diamond by decoupling the surface C--C bonds and endowing the resulting extra bonds with hydrogen atoms, normalizing the superlattice structure at the surface. Pretreatment of the diamond by the oxygen or halogen plasma improves the diode properties; decreasing reverse current, increasing forward current and decreasing the n-value nearer to 1.

Abstract: An azeotropic composition includes a perfluorinated cycloaminoether and an organic solvent.

Abstract: A method of cleaning semiconductor devices which removes or transmutes the contaminants sticking on sidewalls of a pattern or a trench is formed is disclosed. A substrate to be treated on which a pattern or a trench is formed is located in a processing container. A reactive gas which reacts with the contaminants sticking on the sidewall of the pattern or the trench to produce reactive ions which remove or transmute the contaminants is introduced into the processing container. Plasma of the reactive gas is produced by electronic cyclotron resonance in order to produce reactive ions from the reactive gas introduced into the processing container. According to the method, the temperature of the reactive ions in the plasma becomes high, with the result that the motion of the reactive ions in the plasma becomes more active.

Abstract: A method and system for removing a surface layer contaminated with radioactive and/or hazardous material and subsequently treating the waste to remove contaminants and provide an essentially contaminant-free final effluent. The contaminated material is removed by blasting the surface with a pressurized stream of air and sodium bicarbonate abrasive media, and the media is dissolved in water subsequent to the blasing operation. The resulting waste is treated in a sequence of steps including adjustment of pH, aeration and separation into primarily solid and liquid phases by precipitation of solids, which are removed for appropriate disposal. The primarily liquid phase is successively passed through a particle filter, a granulated activated carbon filter and a polishing unit to produce the clean final effluent.

Abstract: A process for the decontamination of solid surfaces contaminated with radioactive or heavy metal species using a solution based on one or more non-persistent complexing agents, or for the chemical cleaning of steam generator sludge using such a solution, or for removing radioactive or heavy metal species from a solution using a combination of a one or more non-persistent complexing agents and a solid support, followed in each case by thermal or thermal-chemical treatment to decompose said non-persistent complexing agent. The preferred non-persistent complexing agents are hydroxamic acids, and the most preferred is acetohydroxamic acid.