Intelligent HUBER throughput control
The feed pump of the belt dryer is fed by six HUBER Screw Press units with a constant inlet DR of 25%. The screw presses, sludge pump and belt dryer form one process unit on this STW. The control systems of these components communicate via direct connection. The intelligent HUBER throughput control system is able to detect even minor variations in the outlet DR of the screw presses already before dryer feeding, for example seasonal variations due to the biowaste. The throughput control system balances even differences as small as ± 0.5% DR by DR-dependent reduction or increase of the dryer throughput. This ensures a constant water evaporation and thus constantly maximum plant efficiency.
Of course, the dryer can optionally be operated with a lower throughput according to the volume of sludge generated in the sewage treatment process. The dryer fully automatically reacts flexibly and efficiently to varying requirements.
Maximum energy efficiency
The HUBER Belt Dryer BT 16 at Innsbruck positively contributes to achieving climate protection goals. Both thermal and electrical energy supply are achieved by means of regenerative energy in the form of biogas from co-fermentation. Additionally, approximately 400 t CO2 a year can be saved due to 450 fewer truck transports that were necessary before. Convincing is the remarkably low energy consumption of the Belt Dryer BT 16 with a maximum thermal energy consumption of 0.8 kWh per kg water evaporation and an electrical energy consumption of below 0.0375 kWh per kg water evaporation. These values set new standards in the field of belt dryers.
Time management and project schedule
We were faced with a tight schedule at any time during this project. The contract was signed at the end of 2016, the installation work on site started already in mid May 2017, and commissioning took place at the beginning of August. The dryer with its many innovations was planned, built, installed and commissioned within eight months (from the date of order placement). After a successful test operation phase with a convincing performance test, the plant was handed over to IKB in December 2017.