CBS Slurry Designs

The compressive strength of the set sealant is measured with ASTM standard specimens of a (2 X 2 X 2 in. ) cube [6]. The slurry from the consistometer is poured in molds and is allowed to set in a curing chamber. It is then taken out after a desired period, and the strength is measured by applying a load on it in a uniaxial press. Knowing the total load and the area of the face on which the load is applied, one can calculate the compressive strength. 

The extent of expansion or contraction of the sealant may be measured by determining the density difference between the slurry and the set sealant. As we shall see below, CBPCs are ideal for sealant application because they expand slightly during setting. 

When the CBS slurry is pumped down a borehole and as it travels through the borehole, its temperature will increase with depth. The higher temperature wiU, in turn, increase the solubility of the oxide components in the slurry. If the solubility of the oxides becomes too high, the slurry may flash set within the borehole prematurely and clog it. To avoid this situation and to allow free flow of the slurry, one must control the solubility of the oxides. Alternatively, one may use components that have their maximum solubility only at the 

Chapter 15 Chemically Bonded Phosphate Ceramic Borehole Sealant 

Using this logic, ANL and BNL scientists have developed a unique approach to develop novel slurry compositions [7,8]. It consists of the following steps  

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