<p>The cement industry faces mounting pressure to reduce carbon emissions and transition toward more sustainable practices. This study introduces a novel all-solid-waste cementitious material (ASWCM) through the synergistic activation of granulated blast furnace slag (GBFS) and lithium slag (LS) using petroleum coke desulfurization ash (PCDA) and calcium carbide slag (CCS). The effects of the PCDA:CCS ratio and GBFS:LS ratio on the properties of ASWCM were systematically evaluated through flowability, compressive strength, hydration analysis, and microscopic morphology. The optimal formulation (PCDA:CCS=1:1, GBFS:LS=3:2) achieved a 28 d compressive strength of 56.7&#xa0;MPa, meeting the strength requirement of 52.5R-grade cement. CCS established an alkaline environment, enhancing precursor dissolution, while PCDA provided SO₄²⁻ for ettringite crystallization. Excessive PCDA reduced system alkalinity, hindering C–(A)–S–H gels formation and inducing microstructural degradation. The balance between ettringite (AFt) and C–(A)–S–H gels formation was crucial for strength enhancement. Environmental and economic assessments revealed that, compared with ordinary Portland cement, the ASWCM reduced the global warming potential by 94.39%, while the total cost decreased by 48.19%, demonstrating its potential as a cost-effective, environmentally friendly alternative. This work demonstrates a scalable pathway to valorize multiple industrial wastes into high-performance, low-carbon cementitious material, advancing circular economy principles in construction.</p> Graphical abstract <p></p>