Negative emission technology is key to decarbonizing China's cement industry

The cement industry, which contributes to 8 % of global CO2 emissions and a large quantity of air pollutants, plays a pivotal role in achieving the carbon neutrality target. However, the question of how to decarbonize the cement industry toward net-zero emissions and the corresponding environmental impact remains unclear. An integrated assessment framework combining a top-down computable general equilibrium model, a bottom-up technology selection model, and a life-cycle assessment was developed to explore the cement industry's car-bon-neutral pathways and associated environmental impact. Results show that promoting energy-efficient technologies is crucial for reducing CO2 emissions in the short term, which can also significantly reduce air pollutant emissions. Improving energy efficiency contributes to reducing the emissions of SO2, NOx, and PM2.5, by 33 %, 35 %, and 8 %, respectively, by 2030. In the long run, achieving net-zero carbon emissions requires implementation of bioenergy with carbon capture and storage (BECCS) and demand-side mitigation measures. The share of kilns equipped with BECCS would increase to 68-75 % by 2060. Corresponding unit abatement costs of CO2 are 484-676 CNY/tonne CO2. However, BECCS triggers adverse side effects by increasing water con-sumption and land cover by 7-11 km3 and 3-4 Mha, respectively, in 2060. Thus, China should take full advantage of energy-efficient technologies to co-control CO2 and air pollutant emissions while avoiding negative effects of BECCS.