Intensity-Based Carbon Reduction Benefits of 'Zero-Waste City' Construction: A Case Study of Mianyang

• • The 'Zero-Waste City' initiative in Mianyang increased the comprehensive utilization rate of solid waste from 84.7% to 89.3%, and the incineration share of household waste rose to 87.3%, while hazardous waste storage rate dropped by 28.6%, indicating systemic improvements in waste management infrastructure. • • Intensity-based accounting, which normalizes for economic and population growth, reveals a net carbon reduction of 10.8×10^4 tCO2eq over the two-year period, contrasting with an absolute-quantity net increase of 127.6×10^4 tCO2eq, underscoring the critical role of intensity metrics in policy evaluation. • • The industrial sector achieved the largest carbon reduction of 40.2×10^4 tCO2eq, followed by the construction sector at 32.8×10^4 tCO2eq, demonstrating that targeted industrial upgrades and construction waste valorization are effective levers for decarbonization. • • Domestic solid waste generation intensity increased, leading to a net carbon increase of 46.1×10^4 tCO2eq, which signals an urgent need for source reduction and improved classification systems to align with consumption-driven waste growth.