Abstract

A two stage hammer mill which reduces recycled glass and its associated contaminants to small glass particles in the 100-800 grit size range and waste. The glass grinder is of light weight, modular construction, such that it may be taken apart, relocated, and restored to operation quickly and easily. A modular design also allows it to be easily cleaned and reconfigured to produce aggregate of selectable size. Located on separate rotors, installed in separate grinding chambers, the two hammer mills are spaced apart from one another and mounted within a common housing. The first stage provides a relatively coarse reduction of the material flow, which then passes into the secondary grinding chamber where the material is further ground. The design of the hammers in this hammer mill are such that they entrain a large quantity of air, accelerate it to high velocity, and drive the mixture of air and material through the system, entraining small, medium and large sized particles. Vacuum pressure is utilized to enhance particle flow through the system and to provide for more precise separation of the finished product as well as separating contaminants from the ground glass. A shaker screen is also employed to facilitate the separation process. Paper shredders are utilized to enhance paper removal.