A solar-assisted large-scale cleaning system (SALSCS) is proposed for air pollution abatement. The system consists of a large-scale flat-plate solar collector, a chimney, and a filter bank. In the basic configuration, an air flow is driven exclusively by buoyancy generated in the collector–chimney system, and PM2.5 and larger particulate matter is separated from the air in the filter bank. The proof of concept is obtained by means of a transient 3D numerical simulation of fluid and heat flow for a full-scale system, implemented in ANSYS Fluent and performed using high-performance computing techniques. The effects of the filter bank on the system performance including heat transfer and fluid flow characteristics are evaluated by studying two system configurations, without and with a filter bank, respectively. The proposed SALSCS system is predicted to be capable of processing atmospheric air at a flow rate of 2.64 × 105 m3/s, corresponding to the volume of 22.4 km3 of polluted air remediated in 24 hours.