Biological Degradation of Base Hydrolysis Products

Biological Degradation of Base Hydrolysis Products Biological treatment is attractive as another process for treating base-hydrolyzed HE byproducts because it has the potential to completely destroy hazardous byproducts. 

They previously developed a consortium (i.e., a mixture) of microorganisms that could be immobilized in biological reactors and that was subsequently used to define process conditions for the treatment of an HE-contaminated waste stream. In this feasibility study performed jointly by LLNL and UCLA, experiments were conducted to define the tolerance of this denitrifying consortium to salinity and dilutions of base hydrolysate. 

The results of the salinity tolerance experiments indicate that the denitrifying consortium can tolerate salinity to levels as high as 10% (1% with sodium chloride). Experiments to determine the compatibility of the microbial consortium with base hydrolysate were conducted with 

PBX-9404 hydrolysate. The results of these experiments indicate that the denitrifying consortium can tolerate hydrolysate levels as high as 10%. The biological treatment of base hydrolysate appears to be limited primarily by salinity and not hydrolysate toxicity. Because base hydrolysis is performed in relatively concentrated solutions, the 10 1 dilutions that would be required for biological treatment would not produce an unreasonable volume of wastewater that would require treatment. 

One waste form of interest is HE-laden activated carbon, which has been used to effectively remove dilute HEs from gaseous- and aqueous-waste streams. However, HE-laden activated carbon is itself a listed hazardous waste, and technologies for its treatment have not been demonstrated. The feasibility of using base hydrolysis as an initial treatment for the removal and destruction of HEs sorbed to activated carbon was assessed and produced very promising results. 

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