By Bill Kleiman, Nachusa Grasslands TNC
This is a hammer mill used to break apart seed heads of all sorts of native seeds.
The mill is under the red housing which has spinning hammers inside. It has a galvanized chute and a custom made seed table on wheels. Mill is by C.S. Bell Co. It is like a life mulcher.
When we want to mill a barrel of seed we dump the seed on the table, or lay the barrel on the table and use the half moon bracket to hold it steady. We feed the seed heads, stems and whatever else we have down the chute. Not the scissors.
Below I am touching a hammer inside the mill and my thumb is on one of four screens we have. The smaller the screen holes the longer the seed heads are exposed to the spinning hammers. We feel confident that most seeds are not damaged from the spinning hammers. If we run some big seed, like a Silphium, then we use the big hole screen. If you get too aggressive you can see broken seeds, but most of the time they look in tact.
Below is vervain seed heads being run through the mill. The pvc pipe is used if some clogging occurs at the inlet. Wear safety glasses.
1,500 pound pile of dry-mesic mix from 2008.
Below we see the blue Baileigh cyclonic dust collector. This is a few horsepower of air suction and it is hooked direct to the bottom of the hammer mill. It is typically used in carpentry shops to collect sawdust. The plant parts are all pulled very fast past the mill, up the clear tube, into the blue cyclone.
In the cyclone the plant parts are circling the blue can very fast. The speed is especially fast in that funnel shaped part of the blue vacuum. Seed is dense with its DNA, fats, proteins and those seed spin down into the white drum. Even pussytoes, Antennaria, won’t go out the exit pipe you see going through the exterior wall. Hard to believe but true.
You can blow seed out the exit tube if you clog the intake tube. Don’t do that.
Below is another mill we have with the vacuum tube hooked right to bottom of mill, so all the product is going up that tube, into the cyclonic separation of the sawdust collector and dropped in he silver can below. Just a light dust gets blown outside.
The mill and vacuum are 220 volts and lots of amps. You need an electrician to wire it up.
When you turn off the mill and vacuum the seed and many other plant parts are in the can. It is still a dusty product so this louvered dust fan helps get the fine dust outside as you pour out the barrel. As you pour seed keep the barrel close to the fan.
Below is from 2004 with a very similar system. Cost is about $10,000.
A few photos of dust collectors: