Application

Aggregate processing plants separate mined or imported material into different individual sizes or a combination of sizes for use in materials like concrete, asphalt, road base, and fill material.  In general, this sorting processis accomplished through the use of a combination of five main types of equipment; feeders (grizzly and/or tunnel), curshers, screens, transfer conveyors, and stacking conveyors or stackers.  The primary purpose of hte feeders is to remove oversized material (typically larger than 5 inces in diameter) and to feed the remaining material into the plant at a constant rate.  Crushers (cone, impactor, or jaw types) reduce oversized material into smaller sizes for processing in the screens.  The screens separate the material into different sizes, depending on the number of decks.  Screens typically have either one, two, or three decks which allow the material to be sorted into two, three, or four different sieve sizes, respectively.  In some cases, multiple screen decks are used to make fewer size separations but at a higher production rate by distributing the material over a larger area of screening media.  Transfer conveyors are used to efficiently move the material from one piece of equipment or area of the plant to another, and the stackers are used to stack the resulting sorted or blended materials into stockpiles.  Because of the varied use and size of each aggregate facility, there is no one specific process train for every plant.