In our last blog post, we took a deep dive into our patented miGRATE™, a migrating biofilm carrier (MBC) technology that is a sought-after process intensification (PI) approach for enhancing existing wastewater treatment processes in water reuse applications.

At WWW™ Arxtera, we have further integrated another successful PI method — WWW™ inDENSE® Hydrocyclone Sludge Densification — as a modular add-on to WWW™ miGRATE that increases control of the ratio of biofilm biomass and densified sludge. inDENSE relies on centrifugal and gravitational forces to differentiate high-density biomass from low-mass, low-density suspension in wastewater, enhancing the performance of traditional activated sludge systems.

Here’s a rundown of how this PI technology works.

An Overview of inDENSE®

Part of the World Water Works Arxtera equipment portfolio, inDENSE® is a centrifugal/gravimetric selection technology, utilizing momentum and gravitational differences to separate and sort solids within the wastewater based on their density, size and specific gravity.

Specifically, inDENSE® retains denser biomass while allowing the lighter fraction of mixed liquor suspended solids (MLSS) to exit as waste-activated sludge (WAS). While conventional activated sludge (CAS) technologies can separate the liquid and solid fractions, ineffective settleability often plagues facilities seasonally or even chronically because of filamentous growth, toxicity, temperature change, septicity and/or other process changes and washout events.

By promoting the retention of higher-density biomass and rejecting light-weight biomass, inDENSE® overcomes settleability issues by enhancing sludge-settling characteristics and improving resilience to biomass loss and other treatment disruptions — especially during cold weather events.

inDENSE® Design and Benefits

Thanks to the hydrocyclone mechanism, inDENSE not only physically selects densified sludge over time, but also encourages aerobic granular sludge (AGS) formation and retention. The hydrocyclones force denser flocs and solids to the cyclone walls, then down through the underflow to be recycled. At the same time, the lighter solids move toward the cyclone center and are pushed upwards through the overflow to be wasted. The static selection mechanism with a certain feed pressure as the only requirement makes inDENSE an extremely adaptable, streamlined and cost-effective upgrade/retrofit option for most wastewater treatment facilities. Its adaptability allows the integration of miGRATE migrating carriers into the overall process flow in a flexible configuration (see image).

Other benefits of inDENSE — which currently has over 100 installations globally — include:

• Greater MLSS control
• Denser sludge selection
• Better sludge properties
• Reduced filamentous and zoogleal growth
• Higher sludge volume index (SVI)
• Enhanced nutrient removal and effluent quality
• Increased clarifier capacity
• Lower energy consumption
• Reduced chemical requirements
• Seamless integration into existing plants

WWW™ inDENSE® Integration With Our Patented PI Technology WWW™ miGRATE™

At WWW™ Arxtera, we have over 15 years of experience in the PI market, and our biological PI processes naturally complement the World Water Works portfolio — including inDENSE. Our latest development of the miGRATE™ process is a standalone migrating biofilm carrier technology that can be modularly combined with inDENSE® to achieve a high-degree ratio control of densified sludge, biofilm biomass and suspended growth for optimal biological treatment efficiency.

To learn more about how we can design and deliver an optimized wastewater treatment solution using our modular approach with inDENSE® and other sustainable water technologies, contact us today.