Increasing production efficiency for BioWanze in Belgium
Biowanze is the largest bioethanol producer in Belgium and one valuable co-product from their process is vital wheat gluten.
The Challenge
In 2008, GEA supplied BioWanze with two very large dryers for drying the wheat gluten extracted from the process. These dryers were protected by safety bursting panels to provide a fail-safe release in the event of an explosion within the dryer. At the time these were the only type of explosion protection that had been given ATEX type approval.
However, the panels were not entirely successful. They occasionally failed because of vibration within the dryer loop. This would require the drying process to be stopped for up to four hours while the failed panels were replaced. These repairs, and the resulting downtime of the machine, were expensive. The problem was heightened when BioWanze decided to upgrade the dryers by increasing airflow and capacity. This caused the panels to fail even more often making the whole process inefficient.
BioWanze had another challenge. Wheat gluten is very abrasive, especially when wet. This was causing extreme wear on the casing of the disintegrator used to mill the wheat gluten at the dryer inlet. The casing is made from very thick mild steel which, after only a few years’ use, had worn very thin and had to be patched by the plant engineers.
The GEA Solution
Meanwhile GEA had been busy. In 2012 it had developed its new GEA CERTEX® explosion vent doors which have ATEX certification. The CERTEX® doors are not vulnerable to deformation caused by heat or pressure fluctuations, nor are they susceptible to vibration that regularly causes standard venting panels to fail. If a door is activated, it does not need to be replaced, it can be reset using a relatively simple sacrificial tab. They can be easily retrofitted to existing systems.
GEA CERTEX®, ATEX-certified explosion vent doors installed at BioWanze bioethanol plant in Belgium
In March 2020, GEA retrofitted 24 CERTEX® explosion vent doors at BioWanze, 12 to each dryer, during a two-week planned shutdown period. Even though delivery of the doors had been delayed by the COVID crisis, the work was still completed on time.
Disintegrator casing upgrade
The excessive wear to the disintegrator casings had been highlighted by the BioWanze engineers. So, working closely with them, GEA engineers fabricatednew casing sections, this time made from highly wear-resistant material and, where the casing is in contact with moisture, duplex stainless steel that is both abrasion and corrosion resistant. During the shutdown, the casings were replaced ready for the restart.
Wheat gluten disintegrator showing modified casing section
The result
Since fitting the CERTEX® explosion vent doors, BioWanze has had no further incidents of vent failure. This has significantly reduced downtime and maintenance costs.
The wear on the disintegrator casing has now been dramatically reduced so the critical tolerance between the tip of the blades and the casing can be maintained. This ensures that the product is ground correctly and consistently to maintain product quality. The upgrade has also reduced maintenance costs and unplanned stoppages.
GEA has changed the design of all its new wheat gluten ring dryers to include these advancements as standard.
