How the SUBRE™ model upgrades wastewater treatment, growing populations and expanding urban centers put immense pressure on existing wastewater treatment infrastructure. Many municipalities and industrial facilities operate plants that are nearing or have already exceeded their designed capacity. Expanding these facilities traditionally requires acquiring more land and pouring massive amounts of concrete, which is incredibly expensive and highly disruptive to local communities.
Facility managers need a way to treat higher volumes of wastewater and achieve stricter effluent standards without physically expanding their plant’s footprint. This operational challenge requires innovative engineering rather than just building bigger tanks.
The SUBRE™ by Fluence offers a highly effective solution. By utilizing advanced Membrane Aerated Biofilm Reactor (MABR) technology, the SUBRE™ model allows operators to upgrade their existing basins. This process significantly increases biological treatment capacity and improves energy efficiency, offering a sustainable path forward for aging wastewater infrastructure.
What is the SUBRE™ Model?
The SUBRE™ model is a strategic wastewater treatment upgrade solution designed to improve the performance of conventional activated sludge (CAS) plants. Instead of building new reactor basins, operators submerge SUBRE™ modules directly into existing tanks.
These modules rely on MABR technology. MABR uses a gas-permeable membrane to deliver oxygen directly to a biofilm that grows on the membrane’s surface. This direct oxygen transfer is highly efficient, allowing microorganisms to break down organic matter and remove nutrients with a fraction of the energy required by traditional bubble aeration systems.
The Mechanics of MABR Technology
In a conventional wastewater plant, blowers force compressed air through diffusers at the bottom of a tank. The bubbles rise to the surface, but only a small percentage of the oxygen actually dissolves into the water for the bacteria to use. The rest escapes into the atmosphere, wasting massive amounts of electrical energy.
MABR technology flips this process. The SUBRE™ modules consist of spirally wound membranes. Low-pressure air flows through the inside of the membrane, while the wastewater surrounds the outside. A robust biofilm naturally develops on the wastewater side of the membrane. Oxygen diffuses across the membrane directly into the biofilm exactly where the bacteria need it to consume pollutants. This method achieves an extremely high oxygen transfer efficiency.
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