The Recycle Station helps you recycle items you don't need any more. To recycle items you need fuel. You can, for example, melt down a iron pickaxe to get back the iron, but the wood will burn to charcoal. The amount of fuel needed is based on the materials melting point. This is specified on the page for the Smeltery.
The Recycle Station is built with 4 Steel, 2 Copper blocks and 2 Pistons.