Nitrate waste

Applicabdity Limitations Photolysis is appropriate for difficult-to-treat chemicals (e.g., pesticides, dioxins, chlorinated organics), nitrated wastes, and those chemicals in media which permits photolyzing the waste. The waste matrix can often shield chemicals from the light (e.g., ultraviolet light absorbers, suspended solids, solid wastes). The photolysis process typically requires pretreatment to remove suspended materials, and the by-products formed may be more toxic than the parent molecules. 

Keywords barbituric acid, nitrogen dioxide, nitration, waste-free, gas-solid reaction... 

Extraction of tetrahedral pertechnetate anion from aqueous solutions using several crown ethers is well known. The coextraction of cesium (or strontium) and technetium from nuclear waste by calix[4]arene-crown-6 has been reported from alkaline media. Although technetium in its common pertechnetate form does not complex directly with crown ethers, pertechnetate extraction may be facilitated by crown ethers as the coanion of sodium (for alkaline nitrate waste). Pertechnetate at trace levels in the waste may be more than a 1000-fold more extractable than the smaller nitrate anion in ion-pair extraction processes.87... 

There are chemical explosion hazards associated with stored reprocessing residues. The explosion near Chelyabinsk in the Urals in 1958 was, it has been suggested, powered by interaction of sodium nitrate and/or nitric acid with sodium acetate/acetic acid in nitrate wastes neutralised with sodium acetate, then stored and allowed to concentrate by radioactive heating [1]. A reprocessing incident at Tomsk in 1993 was apparently caused... 

The densities of the final waste forms were 1.70 and 1.9 g/cm, and the compression strengths ranged from 1400 to 1900 psi (9.8-11.9 MPa) for both the chloride and nitrate waste forms. These values are significantly higher than the NRC land disposal requirement of 500 psi (3.5 MPa) for cement-based waste forms [17]. Thus, salt waste forms of the CBPC at high loadings are relatively dense hard materials that are suitable for salt waste... 

Reprocessing wastes with high concentration of sodium nitrate Wastes from nuclear laboratories and application of radioisotopes... 

To decrease the amount of nitrous oxides released started the process with the addition of various amounts of melted metallic molybdenum wastes to the nitrate wastes. 

The first-cycle raffinate wastes produced at the ICPP are the acid aluminum waste from various test reactor fuels, fluoride-bearing waste from zirconium-matrix fuel, a small amount of stainless steel sulfate waste from fuel from developmental reactors such as the Organic Moderated Reactor Experiment (OMRE), acid stainless steel nitrate waste from the electrolytic dissolution of Experimental Breeder Reactor-II (EBR-II) reactor fuel, and an acid waste from the recovery of uranium... 

In the calciner, the liquid waste is pneumatically atomized from three nozzles at 85-140 gph into the heated 6-ft-deep fluidized bed of solidified granular waste at 400°-500°C. The process is endothermic therefore the bed is heated by in-bed combustion of an oxygen-atomized stream of kerosene. The process is started with a bed of granular material such as dolomite, which is replaced by calcine as the operation continues. By preheating the bed with externally-heated fluidizing air to a bed temperature of 360°-400°C, the atomized kerosene will ignite in the presence of a nitrate waste. 

R.N. Gedye, Y.N. Sadana, and A.C.E. Edmonds, Electrochemical... Recycling of Nitration Waste Concentrated Sulphuric Acid,/. Appl. Electrochem. 17, 731-736, July (1987). 

Similar studies of application of anion exchangers Amberlite IRA-900 (macroporous, polystyrene, strongly basic anion exchanger of type 1, 16-50 mesh) [133-135] and Amberlite IRA-410 (gel, polystyrene, strongly basic of type 2,16-50 mesh) [135] for recovery and removal of trace amounts of Pd(II), Pt(II), Ru(III), Rh(III), Au(III) and Ir(IV) ions from chloride and radioactive nitrate waste waters were carried out by the Els et al. [133, 134] and El-Said et al. 

Although the amount of americium transfer Is somewhat less than desired for an operational system, these experiments show the feasibility of using SLM to remove and concentrate actinides from nitrate waste solutions. Improvements would come from Increased membrane surface area and better complexlng agents In the strip solution. Insertion of the Inorganic Ion exchanger Into the strip circuit would also Improve the process performance. 

We have Investigated the transfer of americium and, to some extent, plutonium from aqueous nitrate wastes using supported liquid membranes of the blfunctlonal organophosphorus extractants DHDECMP and 0()D(1B)CMP0 (+TBF). The results show good transfer and removal If the nitric acid In the feed Is first neutralized to O.IOM to minimize acid transfer and subsequent back transfer of the metal Ion. 

C. W. Francis and C. W. Hencher, Biological Denitrification of High Nitrate Waste Generated in the Nuclear Industry (P. F. Cooper and B. Atkinson, eds.), Ellis HorwoodAViley, Chichester, 1981, pp. 234250. 

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