SBR Is Making A Comeback

Why You Should Consider Sequence Batch Reactors For Your Next Wastewater Treatment Project

The basic principles of biological degradation processes were developed in the early 1900s. Several of these systems were in operation by the 1910s with the first fill-and-draw process used in the United Kingdom. Although the treatment process could achieve good effluent quality, there were many operational issues, which eventually favored the development of the continuous flow type of systems.

Improvements in equipment and technology, especially in aeration devices and computer control systems, have made SBRs a viable choice again. Since then, SBRs are being used successfully to treat both municipal and industrial wastewaters, particularly in areas characterized by low or varying flow patterns. Small municipalities, resorts, and several industries, including food and beverage, pulp and paper, and textiles, are using SBRs as practical wastewater treatment alternatives.

SBRs aren’t only being used in small capacity systems, however. Over the last few decades, SBRs are being used by large cities as well. The largest SBR facility in the world is in Kunming, China, and has 300 MLD/80 MGD capacity.

SBR plants are very practical for several reasons:

  • In areas where there is limited space, treatment takes place in a single basin instead of multiple basins, allowing for a smaller footprint. The same effluent quality can be consistently achieved – as effective as conventional activated sludge processes – by using effective decanters, eliminating the need for a separate phase separation unit (e.g., a secondary clarifier).
  • The treatment cycle can be adjusted to undergo aerobic, anaerobic, and anoxic conditions to achieve biological nutrient removal. Including nitrification, denitrification, and phosphorus removal, to some extent. However, discharge limits that require a greater degree of treatment may require the addition of tertiary treatment following the SBR treatment phase, like other conventional treatment processes.
  • A sequencing batch reactor (SBR) can also act as a very effective high F/M selector, depending on the wastewater strength and feeding strategy. For high-strength wastewaters with a relatively large fraction of the SBR volume occupied by the influent wastewater, a high initial F/M ratio can occur. The subsequent reaction by the batch process is equal to a continuously operated plug-flow reactor.

Since the beginning of our company, we’re consistently asked when SBR would be available in Transcend Design Generator. We take those requests seriously and are happy to note that SBR is now included as an available technology within TDG!

Key benefits of enabling SBR as a technology

  • It’s important to be able to compare batch vs. continuous flow options for different projects. Sometimes, especially when the footprint is constrained and there is not huge variability in peak vs. average flow, a batch process is better.
  • For smaller capacities, it’s critical to be able to compare a conventional SBR w/ MBR or IFAS options. Seeing differences in footprint, power, and chemical consumption can be a key deciding factor.
  • In certain geographies (e.g. India) SBR is accepted as the market standard, so this opens up TDG for those users to compare and contrast the benefits of the standard vs. alternative options.

Run your first SBR design for free by registering here – we’re looking forward to your feedback!


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