What kind of additive is available to mix with the industrial waste?
A Class F fly ash is a good bulking agent that does not harden by itself. Most Class F fly ashes have a pH < 11 which may prevent ammonia release. However you might need a considerable amount of this ash (and therefore a volume increase) to provide load-bearing strengths. Does the ash contain carbon which could reduce the leaching of organic compounds? Is hydrated lime or a lime waste available to react with the Class F ash to produce a pozzolanic reaction. That would provide strength. On the other hand, many Class C fly ashes have a higher pH and are self-cementing. The pH of the final mixed product is generally below 11.5, which is sufficient to prevent the solubilization of amphoteric metals. There will be a temperature rise and potential volume increase due to ettringite formation. Hydrated lime will react with Class F fly ash providing long term strength without temperature rise. But the pH increases to 12.5 until the lime is consumed lowering the pH. Quicklime produces more tempe
