Volatile consolidant

The solid, subliming materials - camphene, tricyclene, menthol and cyclododecane - have been used as temporary, volatile consolidants and release agents (lagers lagers, 1999 Cleere, 2005). These have been chosen to be suitable because of their ease of use and resistance to polar solvents. Of these, cyclododecane is the preferred material because it is the most stable to degradation, has fewer impurities, and has fewer health and safety risks. It is important that the material applied contains as little as possible non-volatile material, which will remain after treatment as a contaminant. 

Biovault is a commercially available, nonproprietary, ex situ treatment for soil and sediment contaminated with chlorinated and nonchlorinated volatile organic compounds (CVOCs and VOCs). The basic biovault process is to promote the degradation of the existing soil contaminants in consolidated piles by stimulation of the indigenous (or augmented) microbial population. The process typically includes low-intensity aeration, moisture control, and supplementation with nutrients. 

Calcines are products obtained by removing the volatile components of the waste, i.e., water and nitrate, at temperatures between 400 and 900° C. The result is a mixture of oxides of fission products, actinides, and corrosion products in particulate form with a specific surface of 0.1 to 5 ra /g. The plain calcine is not very stable chemically because of its large surface area and the chemical properties of some of the oxides, and it is highly friable. To improve the properties of calcines, advanced forms are developed. One such product is the so-called multibarrier waste form, a composite consisting of calcine particles with inert coatings, such as pyrocarbon, silicon carbide, or aluminum, embedded in a metal matrix. Another advanced calcine is the so-called supercalcine. This is essentially a ceramic obtained by adding appropriate chemicals to the HLW to form refractory compounds of fission products and actinides when fired at 1200°C. Supercalcine requires consolidation by embedding in a matrix but does not need to be coated, as the material is supposed to have inherent chemical stability. 

Much work has been reported on the destruction of caking properties of coal. Low temperature carbonization, if carried far enough, drives off enough volatile matter so that the remaining char does not agglomerate. Examples of this are Consolidation Coal Co/s Montour char used in much of the early hydrogasification work, and the more recent char... 

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