Development and application of binder of steel slag, blast furnace slag and zeolite

A low-cost cementing material, steel slag-blast furnace slag-zeolite binder(SBZ), was prepared based on the synergistic action of activation and different waste slag. The basis material ratio was determined by response surface optimization test, which was the steel slag of 38.14%, granulated blast-furnace slag of 38.14%, zeolite of 10%, modified gypsum of 10%, and composite activator of 3.72%. On this basis, the polysilicon waste with the dosage of 8% was used, and the specific surface area of the binder was 420 m²/kg, the 28 d flexural strength reached 6.3 MPa, and the compressive strength reached 42.2 MPa. The SBZ cementitious materials can effectively cure heavy metal lead (Pb²⁺) and chromium (Cr⁶⁺). Compared with ordinary Portland cement, it had higher immobilization efficiency, lower cost and good application prospects. The hydrated calcium silicate, hydrated calcium aluminate, ettringite and zeolite materials in the system had an important contribution to the solidification of heavy metals.