Mill Technology is a Minnesota based company that speicizes in building hammermills that help farmers or comapnies shred or crush grain into smaller pieces to be fed to livestock or turned in Ethanol.
Mill Technology now does Shingle Grinding:
As landfill availability decreases and tipping fees increase, solid waste generators are becoming more interested in finding alternative ways of managing shingle waste. This site discusses the recycling of asphalt roofing shingles, or "composition shingles" including shingle quantities, composition, processing, products, and products made with recycled asphalt roofing shingles.