Desert-derived natural pozzolan tests favorably as fly ash alternative

Sunrise Resources Plc of Cheshire, U.K., reports successful demonstration of a material, mined at the CS Pozzolan-Perlite Project in Nevada, as a substitute for fly ash in concrete. Prior observation of the natural pozzolan entailed mortar specimens, while more recent tests have been conducted on concrete samples and involved a major integrated cement and ready mixed producer.

Sunrise Resources’ CS Pozzolan-Perlite Project in the Nevada desert, north of Las Vegas. The natural pozzolan deposit is concentrated below the mound on the left.

Sunrise technicians evaluated mixtures with the natural pozzolan substituting portland cement at a 20 percent factor plus a control bearing commercially available pozzolan. The CS Pozzolan specimen’s strength development, setting times and shrinkage properties compare favorably against the benchmark commercial sample per results or criteria of ASTM C39 Standard Test Method for Compressive Strength of Cylindrical Concrete Specimens; C618 Standard Specification for Coal Fly Ash and Raw or Calcined Natural Pozzolan for Use in Concrete; and, C1157 Standard Performance Specification for Hydraulic Cement.

“The company is actively engaged in ongoing testing programs with a number of international cement companies and ready mix companies that have operations in the western United States and are potential customers and partners for our future production of natural pozzolan from the CS Project,” says Sunrise Executive Chairman Patrick Cheetham.

Material testing and mine permitting efforts continue at the deposit toward a 15-year extraction schedule and three-phase pozzolan processing capacity ramp up, from 100,000 to 500,000 tons annually. Output would be especially geared to concrete producers in Nevada and California—markets whose combined annual consumption of fly ash is 1.4 million tons, Sunrise estimates.