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Method for decontaminating solutions from natural radionuclides |
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IPC classes for russian patent Method for decontaminating solutions from natural radionuclides (RU 2246772):
The method of electrochemical selection of palladium from nitric acid solutions / 2235374
The invention relates to the field of processing of liquid radioactive waste, in particular, to methods of extraction of precious metals
A method of processing radioactive effluents and precipitation of compounds of manganese (iv), (vi) / 2234153
The invention relates to the field of processing of liquid radioactive waste
Method of extraction recovery of long-lived radionuclides from liquid radioactive waste / 2224309
The invention relates to the field of processing of liquid radioactive waste
A method of processing highly toxic mud and water, the device for its implementation / 2223923
The invention relates to the field of chemical technology and can be used in the purification and concentration of toxic solutes, including radioactive high level of activity
The method of disposal of liquid nitric acid waste containing sulfate ions / 2217823
The invention relates to the field of disposal of liquid waste, in particular to the disposal of liquid nitric acid waste containing radioactive substances
The method of decontamination solutions and/or slurries with a high content of natural radionuclides / 2208852
The invention relates to the field of chemical technology and can be used for neutralization and decontamination of radioactive solutions and waste waters containing Th-232 and child products of disintegration (Ra-228, Ra-224) in excess of established NRB and OSPB, and REE, Sc, Fe, Cr, Mn, Al, Ti, Zr, Nb, Ta, Ca, Mg, Na, K, etc
The method of deposition of technetium dioxide from solutions from the reprocessing of irradiated nuclear fuel from nuclear power plants / 2201896
The invention relates to the field of radiochemical technology, namely the processing of water-tail nitric acid solutions resulting from the reprocessing of irradiated nuclear fuel (SNF) and containing technetium
Method for processing of uranium-containing solid and/or liquid waste / 2200992
The invention relates to the processing of uranium-containing solid and/or liquid waste
A method of processing an alkali metal contaminated with radioactive impurities, and a device for its implementation / 2200991
The invention relates to the field of nuclear energy and can be used for the disposal of alkaline liquid metal coolants
A method of processing technicaly solutions / 2199163
The invention relates to the processing of liquid radioactive wastes generated during the reprocessing of irradiated nuclear fuel
Method for reprocessing of thorium-containing radwastes / 2246550
Invention relates to method for reprocessing of polymetal, multicomponent, thorium-containing radwastes, formed when reprocessing of various mineral, containing rare-earth elements, Nb, Ta, To, V, Zr, Hf, W, U, etc. Method includes treatment of solution and/or slurry with alkaline agent; introducing of sulfate-containing inorganic compound solution and barium chloride; treatment of obtained hydrate-sulfate slurry with iron chloride-containing solution, and separation of radioactive precipitate from solution by filtration. As alkali agent magnesia milk containing 50-200 g/dm2 of MgO is used; treatment is carried out up to pH 8-10; sodium sulfate in amount of 6-9 g Na2SO4/dm2 is introduced as solution of sulfate-containing inorganic compound; barium chloride solution is introduced in slurry in amount of 1.5-3 g BaCl2/dm2. Hydrate-sulfate slurry is treated with solution and/or slurry containing 0.8-16 Fe3+/dm2 (as referred to startingsolution) of iron chloride, followed by treatment with high molecular flocculating agent and holding without agitation for 0.5-2 h. Radioactive precipitate is separated from mother liquor, washed with water in volume ratio of 0.5-2:1; then washed with sodium chloride-containing solution and/or slurry in volume ratio of 0.5-2:1; radioactive precipitate is removed from filter and mixed with mineral oxides in amount of 0.5-0.8 kg MgO to 1 kg of precipitate. Formed pasty composition is fed in forms and/or lingots and presses with simultaneous heating up to 80-1200C.
Method for recovery of platinum metal-containing sludge / 2245383
Invention relates to method for recovery of sludge containing platinum-group metals from equipment using platinum metal-based catalysts. Method includes treatment with aqueous solution of active chemical agent (e.g. sodium-ammonium-substituted ethylenediaminetetraacetic salts) while controlling pH value and removing sludge retained on treated surface with diluted aqueous solution of mineral salts or mixture thereof. pH value is adjusted at 2-10, preferably at 3-9 by adding of organic acid selected from group containing citric, oxalic, maleic, phthalic, adipic, glutaric, succinic acids or basic agents selected from sodium hydroxide, potassium hydroxide, sodium carbonate or potassium carbonate, and hydrochloric acid, sulfuric acid or phosphoric acid is used as mineral acid.
Method for platinum metal recovery from secondary raw materials / 2244759
Invention relates to method for acid leaching of platinum method from secondary raw materials, in particular from ceramic support coated with platinum metal film. Target metals are leached with mixture of hydrochloric acid and alkali hypochlorite at mass ratio of OCl-/HCL = 0.22-0.25 and redox potential of 1350-1420 mV.
Method for reprocessing of lead cakes / 2244758
Claimed method includes heat treatment of lead cake with flux followed by smelting wherein before heat treatment mixture of lead cake, calcium hydroxide, and clinker from lead cake milling is balled to produce pellets. Pellets have fineness preferably of 30-100 mm. Method of present invention affords the ability to increase total coefficient of lead recovery by 3.1 %.
Method of depleting slags from smelting of oxidized nickel ores / 2244028
Claimed method comprises combining slags using extraction principle with number of extractions n approaching infinity. Depleting agent efficient in presence of reducing agent is selected from materials enriched with pyrite, pyrrotine, calcium sulfide, and calcium sulfate; metal and alloys mainly containing Si, Al, Fe, C, etc. as well as reducing and sulfidizing complexes consisting of sulfides, oxides, and reducing substances (C, Me). Carbonaceous reducers, utilized individually or in mixture, are any known carbonaceous reducers. Degree of metal Me recovery is in accordance with conventional extraction equation.
Method for reprocessing of junks of magnesium containing based-based alloys / 2244027
Claimed method includes junk charge into premelted flux at ratio of 1:(5-10); heating up to melt temperature; smelting under flux layer, and separation of metal from flux. Equimolar mixture of sodium chloride and potassium chloride with addition of 2.9-52.6 % (in respect to total flux weight) magnesium fluoride is used as flux, and in melting process flux layer with thickness of 4.5-20 cm is maintained. Method affords the ability to conserve original composition and eliminate additional burdening with magnesium.
The method of obtaining alumina from nepheline raw materials / 2242423
The invention relates to ferrous metallurgy and can be used in the production of alumina by sintering
The method of obtaining selective concentrates of precious metals / 2241773
The invention relates to the field of non-ferrous metallurgy and can be used to obtain selective concentrates of precious metals from anode slimes of electrorefining Nickel
The method of extraction of gallium from powdered waste / 2241052
The invention relates to hydrometallurgy
A method of enrichment of zinc-containing waste of the process of hot-dip galvanizing of metal / 2240363
The invention relates to the field of non-ferrous metallurgy and can be used for processing of zinc-containing waste of the process of hot dip galvanizing
Method for reprocessing of thorium-containing radwastes / 2246550
Invention relates to method for reprocessing of polymetal, multicomponent, thorium-containing radwastes, formed when reprocessing of various mineral, containing rare-earth elements, Nb, Ta, To, V, Zr, Hf, W, U, etc. Method includes treatment of solution and/or slurry with alkaline agent; introducing of sulfate-containing inorganic compound solution and barium chloride; treatment of obtained hydrate-sulfate slurry with iron chloride-containing solution, and separation of radioactive precipitate from solution by filtration. As alkali agent magnesia milk containing 50-200 g/dm2 of MgO is used; treatment is carried out up to pH 8-10; sodium sulfate in amount of 6-9 g Na2SO4/dm2 is introduced as solution of sulfate-containing inorganic compound; barium chloride solution is introduced in slurry in amount of 1.5-3 g BaCl2/dm2. Hydrate-sulfate slurry is treated with solution and/or slurry containing 0.8-16 Fe3+/dm2 (as referred to startingsolution) of iron chloride, followed by treatment with high molecular flocculating agent and holding without agitation for 0.5-2 h. Radioactive precipitate is separated from mother liquor, washed with water in volume ratio of 0.5-2:1; then washed with sodium chloride-containing solution and/or slurry in volume ratio of 0.5-2:1; radioactive precipitate is removed from filter and mixed with mineral oxides in amount of 0.5-0.8 kg MgO to 1 kg of precipitate. Formed pasty composition is fed in forms and/or lingots and presses with simultaneous heating up to 80-1200C.
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FIELD: chemical technology; recovery of deactivated and decontaminated radioactive industrial wastes. SUBSTANCE: proposed method that can be used for deactivating and decontaminating industrial radioactive wastes incorporating Tb-232 and their daughter decay products (Ra-228, Ra-224), as well as rare-earth elements, Fe, Cr, Mn, Sl, Ti, Zr, Nb, Ta, Ca, Mg, Na, K, and the like includes dissolution of wastes, treatment of solutions or pulps with barium chloride, sulfuric acid, and lime milk, and separation of sediment from solution. Lime milk treatment is conducted to pH = 9 - 10 in the amount of 120-150% of total content of metal oxyhydrates stoichiometrically required for precipitation, pulp is filtered, and barium chloride in the amount of 0.4 - 1.8 kg of BaCl2 per 1 kg of CaCl2 contained in source solution or in pulp, as well as pre-diluted sulfuric acid spent 5 - 20 times in chlorine compressors in the amount of 0.5 - 2.5 kg of H2SO4 per 1 kg of BaCl2 are introduced in filtrate. Alternately introduced in sulfate pulp formed in the process are lime milk to pH = 11 - 12, then acid chloride wash effluents from equipment and industrial flats at pulp-to-effluents ratio of 1 : (2 - 3) to pH = 6.5 - 8.5, and pulp obtained is filtered. Decontaminated solution is discharged to sewerage system and sediment of barium and calcium sulfates and iron oxysulfate are mixed up with oxyhydrate sediment formed in source pulp neutralization process; then 35 - 45 mass percent of inert filler, 10 - 20 mass percent of magnesium oxide, and 15 -m 25 mass percent of magnesium chloride are introduced in pasty mixture formed in the process while continuously stirring ingredients. Compound obtained is subjected to heat treatment at temperature of 80 - 120 oC and compressed by applying pressure of 60 to 80 at. EFFECT: reduced radioactivity of filtrates upon separation of radioactive cakes due to enhanced coprecipitation of natural radionuclides. 7 c, 1 ex
The present invention relates to chemical technology, particularly to a technology of inorganic substances and can be used for processing neutralization and decontamination of radioactive waste containing Th-232 and child products of disintegration (Ra-228, Ra-224), and REE, Fe, Cr, Mn, Al, Ti, Zr, Nb, TA, CA, Mg, Na, K, etc. of the Invention can be used for processing multicomponent complex intermediates containing natural radionuclides, industrial products and/or waste generated at different stages of technological processes of complex processing of loparite, zircon, ilmenite concentrates, sludge dump ferrocolumbium production, tailings wet magnetic separation of titanomagnetites, red slime aluminum production waste from the processing of columbite, ferroniobium and other There is a method of recycling (Recycling process of chlorination of loparite // non-ferrous metallurgy, 1987, No.1, p.32-33) radioactive waste - waste molten salt irrigation filter chlorination process loparite concentrates, which consists in leaching of the melt through the drain into the water, stirring chloride slurry with a solution of barium chloride, sulfuric acid, heating the pulp and supply of steel scrap with the order in which Stanovlenie trivalent iron to divalent and raising the pH to 2.5 to 3.5; the treatment of the pulp with the milk of lime to a pH of 4.5 to 5.0, and then with 0.5%solution of polyacrylamide, filtering and washing the precipitate, drying the precipitate and subsequent removal and burial in store special waste (HSO). There is a method allows to increase the degree of concentration of thorium and its contents in the “cake”that is sent to landfill; however, the degree of extraction of thorium from the solution in the sediment - radioactive cake - over 99.9%. For reasons that impede the achievement of specified following technical result when using the known method is unsatisfactory degree of decontamination solutions due to the high radioactivity of the effluent after separation of thorium sludge. Known analogues of the closest to the technical essence and the achieved result for the proposed method is a known method of disposal of radioactive waste (Concentration of chloride waste processing of loparite concentrates of // non-ferrous metals, 1985, No. 2, p.53-56), which is selected as a prototype. According to the prototype of the original radioactive waste is dissolved, the resulting solution (slurry) is treated with a solution l2, sulfuric acid and lime milk, followed by filtration of the slurry, separating the mother liquor from oxyhydrate su is hatago sludge and its disposal in store special waste. There is a method allows to localize the thorium and place it in a convenient location to store the form in store special waste. The disadvantage of the prototype method is unsatisfactory degree cleaning - decontamination solutions from daughter nuclides number of thorium-232, in particular from Ra-224 and Ra-228, which is connected with incomplete coprecipitation of radium with precipitation of barium sulphate, calcium and metal oxyhydrates. Another disadvantage of the prototype method is associated with the need of transporting radioactive fallout (Chekov) in store special waste (HSO), the construction and operation of which requires large capital expenditures. The claimed technical solution aimed at addressing the challenge in improving the environmental and radiation safety. The technical result that can be obtained by carrying out the claimed invention is to reduce the radioactivity of the effluent after separation of the radioactive Chekov by increasing the extent of coprecipitation of natural radionuclides of the number of Th-232, in particular Ra-224 and Ra-228 with the fallout - cakes, as well as in the localization of radioactive elements (thorium and the products of its decay) and transfer them in a radiation-safe form - non-dusting water-insoluble utverjdenie state, resistant to atmospheric precipitation, Grun the new and groundwater, not having a harmful effect on the health of the public and workers, and is suitable for further storage without causing ecological damage to the environment. This technical result in the implementation of the inventive method is achieved in that in the method of decontamination solutions from natural radionuclides, including the production of chloride solutions or slurries by dissolving the radioactive waste processing their barium chloride, sulfuric acid and lime milk, separating the precipitate from the solution, the peculiarity lies in the fact that the original solution or slurry is neutralized with lime milk to pH 9-10 in the number of 120-150% of the stoichiometrically required for the deposition amount of the metal oxyhydrates received oxyhydrate the slurry is filtered, the filtrate is injected barium chloride in an amount of 0.4-1.8 kg BaCl21 kg CaCl2, present in the original solution or pulp, and pre-diluted in 5-20 times waste sulfuric acid chlorine compressors in the amount of 0.5-2.5 kg N2SO41 kg l2in the resulting sulphate pulp consistently give the milk of lime to a pH of 11-12, and then the acid chloride wastewater from washing of equipment and production areas with a ratio of pulp: runoff = 1:(2-3) to a pH of 6.5 to 8.5, the resulting slurry is filtered, desactive the integration of the solution discharged into the sewer, and sulfate precipitate containing sulfates of barium, calcium and oxysulfate iron mixed with oxyhydrate sludge from neutralization of the initial solution or slurry, the resulting pasty mixture is injected under continuous stirring 35-45% (wt.) inert filler, 10-20% (wt.) magnesium oxide and 15-25% (wt.) of magnesium chloride, the resulting composition is subjected to heat treatment at a temperature of 80-120°and pressing under a pressure of 60-80 ATM. The peculiarity lies in the fact that the mixture of oxyhydrate and sulphate precipitation is carried out directly on the filter press by filtration oxyhydrate pulp through a layer of sulphate precipitate, obtained from processing the previous batch of radioactive waste. The peculiarity lies in the fact that as the inert filler is used precipitation and sludge treatment facilities of the companies. The peculiarity lies in the fact that as the inert filler using wood sawdust. The peculiarity lies in the fact that as the magnesium oxide used crushed and heat treated magnesium-containing mineral oxide materials selected from the series, serpentine, and/or brucite, and/or magnesite. The peculiarity lies in the fact that as the magnesium oxide used asbestos waste production. The peculiarity lies in t is m, as the magnesium chloride used solution and/or slurry of magnesium chloride, for example condensed magnesia slurry formed during the purification of exhaust gases from CL2and/or Hcl magnesia suspension. Under other equal conditions, the proposed method is characterized by new techniques of performing actions and the new order of execution of actions, the use of certain substances, without which it is impossible the implementation of the method, the new modes and parameters of the process, ensures the achievement of the technical result in the implementation of the claimed invention. Check the patentability of the claimed invention shows that it corresponds to inventive step, as it is not necessary for professionals explicitly. The analysis of the prior art indicates that in book, journal and patent literature contains no data on decontamination solutions from natural radionuclides by sequential processing of initial solution (slurry) first lime milk, then after separation of the oxyhydrate precipitate with chloride of barium, spent sulphuric acid, chlorine compressors in the amount of 0.5-2.5 kg N2SO41 kg BaCl2then the introduction of the milk of lime slurry, acid chloride wastewater from equipment washing the production sites at a ratio of pulp:runoff = 1:(2-3), filtration of the pulp, mix radioactive sludge with an inert filler, magnesium oxide, magnesium chloride and receiving units. Analysis of the totality of the features of the claimed invention and achieved technical result shows that between them there is a causal relationship, which is expressed in the fact that the process of decontamination solutions from natural radionuclides in strictly defined above conditions, modes, and parameters of the process: the sequence of operations, the availability of new activities, the introduction of certain substances, defined by the ratio of the reagents, and a well-defined procedure for the introduction of reagents provide an improved decontamination and reduction of radioactivity of the effluent after separation of the radioactive fallout at the expense of increasing the degree of co-precipitation of natural radionuclides of the number of Th-232, in particular Ra-228 and Ra-224 hydrated, sulfate and oxysulfate precipitation - cakes, the localization of radioactive metals and their conversion into an environmentally safe form of non-dusting water-insoluble utverjdenie state, resistant to atmospheric precipitation, ground and underground waters, not having a harmful effect on the health of the public and workers, and is suitable for further skladi the Finance without causing environmental and radiation damage to the environment. For violations of the above ratios of the reagents, a well-defined procedure for the introduction of reagents, mixing, process conditions, sequence, etc. of the above technical result is not achieved. It should be noted that established a causal relationship is not obvious for specialists and not derived from literature data on the chemistry and technology of rare metals. Information supporting the implementation of the present invention to provide the above technical result, and comparing the effectiveness of known (the prototype) and the proposed technical solutions described in the example. Example As solutions containing natural radionuclides for conducting experiments, were used: waste molten salt irrigation filter chlorination process loparite concentrates. Solutions containing, wt.%: 2,5 ThCl4, 20 ll3, 7 LnCl3and impurities TiCl4Nbl3, TaCl5, NaCl, KCl, MgCl2, l2, water-insoluble residue (5%), was dissolved in water at W:T=4:1. With the obtained chloride pulp comparative trials on the effectiveness of decontamination and to determine the effectiveness of known (prototype) and predlagaemoj the methods. According to the method the slurry was heated to 75±5°and treated With 200 l of 10%solution of barium chloride and 50 l of 78%sulfuric acid solution, and then neutralized with calcium hydroxide to pH 8.0±0.5, it was filtered on a plate and frame filter press. In the filtrate measured αradioactivity, and then again sent for decontamination according to the described scheme. The process of decontamination were thus 6 times before reaching the radioactivity of the filtrate 1 EQ-mg thorium/DM3. In the proposed method the pulp was treated with lime milk to a pH of 9.0±0.5 in the amount of 130% of the stoichiometric required for the deposition amount of the metal oxyhydrates and filtered to frame filter press. The mother solution-the filtrate was treated with 50 DM310%-aqueous solution of barium chloride and 10 DM310%-aqueous solution of spent sulphuric acid chlorine compressors, after which the pulp was treated with lime milk to a pH of 11.5±0,5 introduced 2 m3acid chloride wastewater from washing of equipment and production areas to pH 7.0±0.5 in. Thus obtained slurry was filtered, the filtrate measured αradioactivity and dumped into the sewer. Fallout - oxyhydrate and oxysulfate - mixed, the resulting pasty mixture was injected under continuous stirring to 42.5% (wt.) inert filler, 15,5% (wt.) OK the IDA magnesium and 20% (wt.) of magnesium chloride, then the obtained composition was subjected to heat treatment at a temperature of 100°and pressing under a pressure of 75 ATM. Research and testing has shown that the process of decontamination solutions from natural radionuclides in the proposed method gives the possibility to deactivate RAO to established standards, and transfer of radioactive Chekov in utverjdenie the state provides them with environmentally - safe storage without causing damage to the environment, public health and staff: obtained in accordance with the proposed method "blocks", as shown by tests that are resistant to fluctuations in ambient temperature (-50 to +50° (C), no dust, vodorastvorimyi and resistant to atmospheric precipitation, groundwater and subsurface waters. 1. The method of decontamination solutions from natural radionuclides, including the production of chloride solutions or slurries by dissolving the radioactive waste processing their barium chloride, sulfuric acid and lime milk, separating the precipitate from the solution, wherein the source solution or slurry is neutralized with lime milk to a pH of 9÷10 120-150% of the stoichiometrically required for the deposition amount of the metal oxyhydrates received oxyhydrate the slurry is filtered, fil the rat injected barium chloride in an amount of 0.4÷ 1.8 kg BaCl21 kg CaCl2, present in the original solution or pulp, and pre-diluted in 5-20 times waste sulfuric acid chlorine compressors in the amount of 0.5÷2.5 kg N2SO41 kg BaCl2in the resulting sulphate pulp consistently give the milk of lime to a pH of 11÷12, then the acid chloride wastewater from washing of equipment and production areas with a ratio of pulp : runoff = 1: (2÷3) to pH 6.5÷8,5, the resulting slurry was filtered and decontaminated solution discharged into the sewer, and sulfate precipitate containing sulfates of barium, calcium and oxysulfate iron, mixed with oxyhydrate sludge from neutralization of the initial solution or slurry, the resulting pasty mixture is injected under continuous stirring 35-45 wt.% inert filler, 10÷20 wt.% magnesium oxide and 15÷25 wt.% of magnesium chloride, the resulting composition is subjected to heat treatment at a temperature of 80-120°and pressing under a pressure of 60-80 ATM. 2. The method according to claim 1, characterized in that the mixture of oxyhydrate and sulphate precipitation is carried out directly on the filter press by filtration oxyhydrate pulp through a layer of sulphate precipitate, obtained from processing the previous batch of radioactive waste. 3. The method according to claim 1, characterized in that the image quality is as inert filler used precipitation and sludge treatment facilities of the companies. 4. The method according to claim 1, characterized in that as the inert filler using wood sawdust. 5. The method according to claim 1, characterized in that the magnesium oxide used milled and heat treated magnesium-containing mineral oxide materials selected from a number of serpentinite and/or brucite, and/or magnesite. 6. The method according to claim 1, characterized in that the magnesium oxide used asbestos waste production. 7. The method according to claim 1, characterized in that the magnesium chloride used solution and/or slurry of magnesium chloride, for example condensed magnesia slurry formed during the purification of exhaust gases from CL2and/or Hcl magnesia suspension.
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