A New Compressor Becomes a Fresh Breath for an Water Treatment Old Plant
The Flexibility Edge
Iren and Robuschi technicians worked side by side during the project to refurbish the Emilia wastewater treatment system. “We began with a prototype, the WS 65, and then moved on to a solution with dimensions more in keeping with the system requirements. As a result, we chose select the size WS 85” explains Canovi. The Robuschi technology showed straight away that it possesses the operating flexibility necessary for the requirements of the sewer plant, as it allows the compressor to be switched on and off as needed without creating any problems connected to start-up; this is a feature that other technologies don't have. “This flexibility, which supports the process and know-how without invading them, is a great advantage and a unique feature that can be considered advanced in terms of energy savings.”
The goal was to reach the ideal solution that permits the system not to waste electricity, and it was reached by adopting a control system with a logic implemented by the Iren technicians. Robuschi then improved the solution, adapting it to the specific context. As Canovi explains, the next step will be to combine the new logic with air production division. “To supply the system in moments of higher demand, we'll probably need another unit with a power rating lower than the WS 85 to meet and guarantee the demand with the utmost flexibility in all load situations.” The Rubiera system has been operating with the final layout (the new structure combined with Robox Energy WS 85) for nearly six months and, even if it's still too soon to verify the effective advantages of this new configuration, the initial data can already be assessed.
Energy Consumption Halved
“Thanks to the electricity measurement units that were already installed to measure the energy consumption of the compartment with the old system configuration, we've been able to monitor the electricity consumption as the project proceeded. As a result, we've seen that the new logic resulting from the Iren control system (making it possible to switch off the machines when not in use) meant a 30 % reduction in the electric consumption of the compartments compared with the original configuration, and by installing the size WS 85 we've obtained a further reduction of 20 % in air generation alone, for total energy savings of 50 % for the compartment”, Canovi adds.
This level of reduction in consumption for such a significant cost item as energy is, in itself, a praiseworthy achievement. It can still be improved however, the expert thinks: “The excellent level already reached can be increased by a few percentage points more if we improve some system components, such as the size and efficiency of the permeable mat for the air supply. These are just simple operational measures, but they can raise even further the already high level that we've reached with the refurbishment.”