How does carbon monoxide reduce zinc oxide in a blast furnace?

In a zinc-lead blast furnace, the reduction of zinc oxide (ZnO) is a critical pyrometallurgical process. Carbon monoxide (CO) acts as a reducing agent by stripping oxygen from the zinc oxide, resulting in the production of zinc metal and carbon dioxide (CO₂).1

The chemical reaction is represented as follows:
$$ZnO+CO\to Zn+C{O}_2$$

Because this reaction is endothermic, it requires the continuous input of external heat to maintain temperatures between 1,300 and 1,350 °C (2,375 to 2,450 °F) to proceed at an efficient rate. In the furnace, this heat is generated by the combustion of coke with preheated air blown through tuyeres at the base. This combustion also produces the carbon monoxide gas that rises through the furnace shaft to react with the descending charge of zinc-bearing materials.123

Unlike other metals, the zinc is produced as a vapour, which must be rapidly cooled in a lead-splash condenser to prevent it from reverting to zinc oxide upon contact with the carbon dioxide byproduct.24