Lab Scale Activated Sludge Reactors

Lab Scale Activated Sludge ReactorsLab scale activated sludge reactors have been employed by those in academia who study wastewater systems for decades to analyze the effects of selected variables on the treatment of many unique waste streams. Their purpose is to mimic the conditions found in full scale systems as closely as is possible in a system that can be confined to a typical laboratory bench top. The advantage of lab scale reactors over other methods of testing the effectiveness of certain treatment strategies is the ability to observe the process of an open system for an extended period of time. By monitoring several data points, it is possible to see the long term effects of operational changes to a system before instituting them on site.

At EBS, we have several lab scale activated sludge reactors in which we can perform an assortment of long term studies. Commonly studies will focus on how the health of a biomass is affected by the introduction of a new waste stream to the normal influent of a given WWTP. Other methods of studying wastewater treatment, such as respirometry, make it possible to determine the acute effects of a proposed or existing waste stream on the activated sludge present in a system. Lab scale reactors have the added benefit of providing insight into whether or not chronic effects can be expected when introducing a potentially inhibitive waste, or attributed to an existing element of the influent. It is also possible to determine the outcome of bioaugmentation, among other factors, on an activated sludge plant.

In order to monitor any changes occurring in the lab scale reactors, we can regularly obtain values from chemical testing (typically two to three times a week) for pH, ammonia, ortho-phosphate, soluble COD (chemical oxygen demand), MLSS (mixed liquor suspended solids), MLVSS (mixed liquor volatile suspended solids), 30-minute settling, supernatant TSS, DO (dissolved oxygen), DOUR (dissolved oxygen uptake rate), influent and effluent BOD (biochemical oxygen demand), and any other tests required or requested. We also analyze the samples for microbiological characteristics such as basic microscopic evaluations, total & active bacterial counts, culturable counts and total & free ATP (adenosine triphosphate). The lab scale systems are monitored seven days a week to ensure the proper operation of the reactors throughout the duration of the study. We will also maintain the conditions of our reactors as close to those found at your facility as possible by regulating parameters such as MLSS, pH, temperature, etc.

Analyzing the effects of operational changes to a lab scale system enables us to provide our clients with valuable insight into the potential consequences that can be expected when the same modifications are made on site. This can help to diminish the risk associated with making deviations, whether minor or significant, from the normal procedures of a WWTP. If you have any questions about our lab scale activated sludge reactors, or about any of our other products or services don’t hesitate to contact us.


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