1. opening of raw material

The round or square straw bales are placed on a storage conveyor. The square bales are entered directoy into the opening unit. The round bales first need to be cut in equal lengths with a guillotine cutter. The opening unit opens the straw and ensures a relatively even flow of material towards the decorticating section.

> enlarge

2. decorticating

The opened straw is aspirated from the opening unit and fed into a first decorticator. This machine detaches the core from the fibre and produces a mixture of fibre and core. At the exit it is aspirated and discharged into a first fibre separator where a large part of the core is removed. The fibre leaving the first separator is usually not clean enough for a refining line. Therefore it is aspirated and fed to a second decorticator that re-opens the fibre and does the final decorticating. The fibre and core mixture is then aspirated again and discharged in a second separator. The core is collected in the same way as in the first separator and it is transported with the same pneumatic conveyor.

After the decorticating section the fibre contains ± 15 to 20% of core. This fibre can be used in the paper industry but for some applications further processing is necessary.

> enlarge

3. fibre refining

The fibre with ± 15 to 20% of core is aspirated and baled with a buffer baler or fed directly to a refining line. The fibre that is baled can be processed later. At the end of the refining line, the fibre contains less than 5% of core. This is called technical fibre and can be applied in insulation or composite material.

> enlarge

4. core cleaning

The core is separated in the decorticating and the refining section and transported to a buffer silo. At this point the core contains a relatively high percentage of short fibres. For some applications further cleaning is required. This is done in a Duvex, which can also establish a calibration of large and small core particles. The clean core can be stored in bulk or it can be pressed into plastic bags.

> enlarge

5. pneumatic transport

To transport the fibre or the core from one process to the next, the principle of pneumatic transport is applied. This makes it easy to extract dust from the material during transport. The dust is collected in several filter units and eventually it can be evacuated as briquettes or pellets, depending on the customers needs.

> enlarge