摘要:
An environmentally sound process is described for the remediation of waste materials that allows the separation, recovery and decontamination of metals. The method includes chemically reducing essentially all of a reducible toxic and potentially hazardous metal-containing component of a waste composition. The waste is directed into a molten metal bath, including a first reducing agent which, under the operating conditions of the molten metal bath, chemically reduces a metal of the metal-containing component to form a dissolved intermediate. A second reducing agent is directed into the molten metal bath. The second reducing agent, under the operations of the molten metal bath, chemically reduces the metal of the dissolved intermediate. The rate at which the second reducing agent is directed into the molten metal bath, relative to the rate at which the component of the waste is directed into the molten metal bath, is sufficient to cause essentially all metal-containing intermediate formed to dissolve in the molten metal bath, thereby indirectly chemically reducing the component of the waste. This indirect reduction technology can remediate a variety of materials, including ash metal-contaminated municipal waste, vitreous slag-like materials and spent metal catalysts, while allowing the recovery of remediable metals.
摘要:
A method and a system for catalytically converting a hydrogen component in a hydrogen- and carbon-containing feed to dissolved hydrogen and for oxidizing the dissolved hydrogen to water is disclosed. Hydrogen- and carbon-containing feed, such as municipal garbage, low grade fuel oil and organic or inorganic sludge, is introduced to a molten bath system. The molten bath system includes first and second immiscible molten metal phases. Carbon and hydrogen component in the feed are converted to dissolved carbon and dissolved hydrogen, respectively. The dissolved carbon is oxidized in the first molten metal phase to carbon monoxide, which then migrates out of the first molten metal phase. As dissolved hydrogen accumulates in the first molten metal phase, it nucleates and migrates to the second molten metal phase, where it is oxidized and forms water vapor.
摘要:
A process for dehalogenating halogenated hydrocarbons is disclosed wherein after vacuum dewatering of the hydrocarbon it is admixed in a reaction vessel with a dispersion of sodium of particle sizes of 10 microns or less, heated above 97.7.degree. C. to liquify the sodium and the atmosphere above the admixture is converted to argon gas. Thereafter the admixture may be saturated with hydrogen by dissolution to facilitate the reaction. The reaction products are cooled, and the dehalogenated hydrocarbon is removed after filtration.
摘要:
Cholinesterase inhibiting agents such as nerve gas agents and pesticide agents are destroyed by reaction with molten aluminum and the gaseous products are analyzed and recycled if they are not essentially free of such agents.
摘要:
A method for destroying toxic organic chemical products. The method is particularly adapted for the destruction of polyhalogenated polyphenyls, especially polychlorinated biphenyls (PCBs). The toxic organic chemical product is intimately contacted and reacted with a molten mixture of an alkali metal hydroxide and an alkali metal nitrate, so that it is converted to harmless products which, in the case of PCBs, include a halide salt, at least one carbon oxide, and water. By incorporating a substantial excess of nitrate in the mixture most of the salt is caused to precipitate and to settle out to the bottom for easy removal.
摘要:
One aspect of the invention provides a system for treating wastestream, particularly a liquid or aqueous radwaste, for safe disposal and, in final processing, converting it into one or both forms including an aqueous form for safe discharge to the environment and a solidified form for safe disposal. Another aspect provides the capacity to employ a step where a specific target element strategy can be set up synchronizing sorbent substance choices and multiple recycle options to remove target substances from wastestream as a part of its Sorption or Powder Sorbent Isotopic Reduction step (II). Other steps cooperate with Sorption step (II) including Oxidation (I) to inactivate or destroy existing chelants, Solid-Liquid separation (III), and Selective Ion Exchange (IV) to deliver the wastestream to final processing. Still further aspects of the invention address the recovery and safe handling of substances such as C-14.
摘要:
Described are method of treating a radioactive organic waste stream comprising: (a) mixing a radioactive organic waste stream comprising organic compounds and radionuclides with phosphoric acid to form a reaction mixture; (b) heating the reaction mixture to a desired temperature in the presence of an oxidant to oxidize organic compounds present in the waste stream, and removing oxidized organic compounds from the reaction mixture; (c) optionally, adding a reducing agent to the reaction mixture to form insoluble radioactive metal phosphate compounds comprising one or more of the radionuclides, and separating the insoluble radioactive metal phosphate compounds from the reaction mixture; (d) optionally, adding a fluorine compound to the reaction mixture to react with uranium that may be present in the reaction mixture to form uranium hexafluoride, and removing uranium hexafluoride from the reaction mixture; (e) adding ammonia to the reaction mixture to neutralize phosphoric acid and to form ammonium phosphate complexes comprising one or more of the radionuclides, and separating the ammonium phosphate complexes from the reaction mixture to yield an ammonium phosphate liquor, wherein the method includes performing at least one of steps (c) and (d).
摘要:
The present invention discloses a method for solidifying and stabilizing waste acid including steps of condensing waste acid containing phosphoric acid to reduce the volume; mixing the condensed waste acid with waste acid containing fluoroboric acid to solidify and stabilize the mixed waste acid. The pH of the mixed acid is adjusted by adding barium hydroxide as a neutralizer. The efficiency of solidifying waste acid can be improved by partially granulating and by adding solidifying agent indirectly. The method of the present invention can prevent intensely exothermic reaction caused by adding solidifying agents. Furthermore, the method of the present invention is controlled in a temperature of 30 to 45° C. to improve the polymerization of the mixed waste acid so that the efficiency of solidification thereof can be also improved.
摘要:
Process for confinement of waste containing at least one chemical species to be confined, by in-can vitrification in a hot metal can into which waste and a vitrification additive are added, the waste and the vitrification additive are melted to obtain a glass melt which is then cooled, characterised in that at least one oxidising agent is also added into the metal can and in that the concentration of oxidising agent(s) expressed as oxide(s) in the glass melt is between 0.1 and 20% by mass, preferably 4 and 20% by mass, even more preferably 5 and 15% by mass, and even more preferably 10 and 13% by mass of the glass melt mass.
摘要:
The invention consists of a method for treating polychlorinated biphenyl (PCB) contaminated media by: a) combining the media with a fluid containing one or more liquid hydrocarbons to form a media/fluid mixture; b) sonicating the mixture at audio frequency to extract PCB from the media into the fluid; and c) treating the fluid with sodium-containing alkali metal. The method may include additional steps to reduce the size of the media. Alternatively, the fluid can be decanted from the media after sonication and treated separately with sodium-containing alkali metal.