MBR system saves plant 20 percent in energy

MBR system saves plant 20 percent in energy

As a pharmaceutical producer, Istituto De Angeli needs to follow strict guidelines about the quality of water it releases back into the environment. A membrane bioreactor solution from Xylem has enabled the plant to increase the efficiency and capacity of its wastewater treatment, while using 20 percent less energy.

Located in Reggello, Italy, outside Florence, Istituto De Angeli produces 90 million pharmaceutical items per year, including syrups, mouthwashes, sprays, capsules and tablets. About 70 percent of the company’s production is exported to 70 countries around the world, for well-known brand names.

Investments in modern industrial automation systems have enabled the plant to efficiently manage its entire operations. In addition to maximizing productivity, the plant also needs to be able to operate in compliance with strict environmental standards. Since the plant’s wastewater is discharged into a nearby river, it is essential that the wastewater is properly treated.

Looking for a more effective solution

In recent years, the plant has met these environmental regulations using a membrane bioreactor (MBR) made out of ceramic material. This technology has enabled the plant to meet the increasingly strict legal limits for discharging wastewater, however, at a very high operating cost. The MBR system required significant maintenance, which entailed costs for both replacement parts and man-hours. As a result, Istituto De Angeli began looking for a more effective and reliable solution.

The plant selected Xylem, which has been supplying Flygt pumps to Istituto De Angeli for several years, to help design and calibrate a new MBR system. Using GE membranes, Xylem’s MBR solution would offer better effluent quality and lower lifecycle costs than conventional activated sludge treatment. GE membrane technology eliminates the need for secondary clarifiers and tertiary treatment. This increases performance while taking up a smaller footprint.

The membranes also reduce the content of dissolved pollutants and bacteria. The polymer that the membranes are made of enable them to remove impurities larger than 0.035 microns. At the same time, the ultrafiltration membranes have a high permeability, which allows them to treat a high flow of water even when the filtration surface is limited.

Designing the new MBR system

After testing the new membranes, Istituto De Angeli began constructing a new MBR system. The objective was to use the new system to purify part of the wastewater in parallel with the traditional MBR system. The new system would treat 13 cubic meters of wastewater per hour, but it would be able to handle spikes of up to 18 cubic meters per hour.

Xylem technicians were responsible for planning and ensuring that the new MBR system worked as it should. In particular, the technicians ensured that the membranes could properly clean themselves. The quality of the incoming slurry must match the flow of air bubbles and pressure, so that deposits are shaken loose from the membranes.

20 percent in energy savings

After the new MBR system was put in operation, Istituto De Angeli was very pleased with the results.

“In the first few months of operation, we have seen an energy saving of 20 percent, compared to the traditional MBR system,” says Francesco Bellini, Utilities Supervisor at Istituto De Angeli. “In addition, our wastewater is now of a particularly high quality, and we expect the membranes to last at least 13 years. Our goal is to continue to optimize the cycle to reduce energy consumption even further.”

by Simon