There are two main types of asphalt-mixing plants: batch and continuous.
Batch Asphalt Plants
To visualise the batch process, think of using a mixing bowl when cooking. All the ingredients are added to the bowl in the amounts specified in the recipe. Then they are mixed, and the bowl is emptied.
The batch mixing process follows a similar approach. Aggregates, polymers and other materials are added to the mixer. The materials are blended and, when that process is complete, the mixer is completely emptied.
The process can then start again, often with a new recipe.
Continuous Asphalt Plants
The continuous process in theory has no end. Materials enter the mixer and are blended as they advance toward the exit and are conveyed to storage silos.
With continuous plants, new materials are constantly entering the mixer to replace the departing materials. There is a continuous flow of materials.