The rapid growth of Taiwan’s coffee market has led to the generation of more than 10000 tons of spent coffee grounds (SCGs) annually, which are typically incinerated or landfilled, resulting in significant carbon emissions. In this study, we developed and validated a circular economy framework for coffee grounds valorization, integrating waste collection, drying, pyrolysis, and activated carbon (AC) production with a digital reverse logistics platform. A compact in-store dryer was designed and tested, achieving a consistent removal of >20 g of water per 100 g of grounds within 15 min at 105–185 ℃. Grounds samples were sieved to ≤150 μm prior to pyrolysis. Batch pyrolysis trials (20–500 g, 500–750 ℃) demonstrated stable carbonization yields above 40% under optimized conditions (500 g at 500 ℃, 60 min, ~43% yield). The resulting AC met industrial quality standards, exhibiting surface areas of 630–680 m²/g, iodine concentrations of 690–730 mg/g, and methylene blue adsorption capacities of 150–180 mg/g. Application tests confirmed >96% chlorine removal efficiency in water filtration. A web-based service platform was simultaneously developed to record, analyze, and manage collection and recycling data across pilot 7-Eleven stores, enabling traceability and integration into existing logistics systems. Economic projections indicate a potential value creation of NT$1.5M in the first year, increasing to NT$45M by the third year. The findings demonstrate the feasibility of coupling biomass-derived AC production with digital service flows to reduce waste disposal burdens and establish replicable circular business models within large retail ecosystems.