Good end results when Ekeby treatment plant built a new sludge treatment facility
Eskilstuna Strängnäs Energi och Miljö needed to build a new sludge treatment facility. In 2017, FVB was tasked with project management and programming for the automation part.
The project as a whole includes a building, two sludge presses and a storage silo for sludge. Besides managing the process for sludge dewatering, FVB also managed HVAC, heating and ventilation.
The process itself can be described as follows: the retted sludge is pumped up from a pool and flocculant is added before it is fed into sludge presses that dewater the sludge. The sludge is collected in a tank that holds 200 cubic meters, which corresponds to between 150 and 175 tons of sludge, depending on its dry content. There is a loading unit for trucks under the tank where each truck takes about 10 tons of sludge, which is then taken to a landfill.
- Siemens S7-300 PLC with distributed IO for controlling processes, HVAC and heating.
- Each process section has a Siemens 12 inch Comfort panel for local operation.
- Profibus communication to nine ABB frequency converters for motor control.
- Signal exchange of process values for regulation between two existing control systems was also part of the project.
- Control for PLC is programmed in Siemens TIA Portal.
- HMI process images were designed and animated in the iFix SCADA master system for central monitoring of alarms and history.