Biomass fuel molding: Shaping biomass into fuel

What is biomass molding fuel?

Biomass fuel molding, also known as BMF, refers to the compression of agricultural and forestry waste into briquettes, bars, or pellets. The production process involves raw material collection, crushing, blending, drying, molding, discharge, cooling, and packing, using specialized equipment. Biomass fuel has high heat value, low pollutant emission, making it an excellent alternative to fossil fuels.

How are biomass fuels made?

Biomass molding involves compressing dry and crushed agricultural waste into solid briquettes or pellets. The high lignin content in biomass materials acts as a binder when melted under high temperatures, effectively gluing the materials together. In some cases, binders or additives may be added to the mixture. The biomass molding equipment typically includes crushing, hot molding, and shape maintenance processes.

The compressed biomass fuels find applications in heating stoves, industrial boilers, and power plants. They offer several advantages, including high density, good burning performance, high heating efficiency, low ash residue, and low pollutant emission. Additionally, they are easy to ignite, store, and transport, with a promising market outlook.

Biomass fuel molding equipment can be classified into four types based on different molding technologies: stamping briquette press, screw extruding briquette machine, ring die pellet machine, and flat die pellet machine.

Stamping briquette press

Stamping briquette press utilizes the two-way squeeze of reciprocating pistons to mold biomass materials into briquettes. It is capable of producing briquettes of various sizes and shapes by replacing the extrusion mold. However, due to its short extrusion time, the density of the briquettes produced by a stamping briquette press is relatively low.

Ring die pellet machine

The molding process of a ring die pellet machine involves a ring die with multiple holes and 2 or 3 press rollers inside the ring die. The raw materials are fed into the compression chamber, where the rollers press the materials outward, forcing them into the holes on the ring die. As the materials pass through the holes and exit the die, they form solid cylindrical pellets. These pellets are then cut into shorter lengths by slicers. The ring die pellet machine is known for its large capacity and is suitable for use in medium to large wood pellet factories.

Flat die pellet machine

The flat die pellet machine operates with a vertical shaft and a roller that attaches to the top side of the flat die. The raw materials are dropped onto the flat die, and the roller presses them downward. As a result, the materials are squeezed out through the holes on the flat die and subsequently cut by a slicer. The flat die pellet machine is known for its smaller size and lower cost, making it suitable for home use and small-scale wood pellet factories.

Screw extruding briquette press

The screw extruding briquette press shares a similar structure with a meat grinder. Its molding structure consists of a screw propeller, compression chamber, holes on the molds, and a slicer. Once the raw materials are fed into the briquette press, the screw propeller pushes them forward, allowing them to pass through the holes on the molds. As a result, the materials are shaped into cylindrical bars. Finally, the slicer is used to cut these bars into the desired length.