You can make wood or biomass pellets out of many different materials. Both softwood and hardwood are both used and produce excellent results. What's really interesting though is that it's also possible to make biomass pellets out of a wide variety of materials. Some of the possible ingredients are - switch grass, grain, corn cobs, corn stalks, paper, sawdust, distiller grain, and many others. There are many potential materials that can be used with good results. The common rule of thumb is that if you can reduce the size of your chosen biomass into granular form, you can make pellets from it.
Need to figure out moisture content.
Moisture Content is usually required for biomass pellet making machine. Generally, the ideal moisture content of the material is 15%, if lower than 15%, some water or vegetable oil will be added and mixed before production. If higher than 15%, there shall be equipped with a dryer.
The Processing of making biomass pellets
As they say, the devil is in the details. Depending on what your raw materials are, i.e. switch grass versus sawdust for instance, the "recipe" will change. We'll use dried wood as the raw material for the example that follows.
First, if the raw material is larger than 1/4", it's broken down in the hammer mill to a smaller particle size. Next, the raw fiber is either put into the pellet maker and heated with steam, pressure, a combination of both. This causes the naturally occurring lignin to plasticize and hold the pellet together after it passes through the pellet maker machine and cools down.