ALMA BIO SBR – Biological Wastewater Treatment in a Sequencing Batch Reactor
Have an SBR system designed:
Maksim Neubauer
Head of International Project Development
What is an SBR reactor?
An SBR (Sequencing Batch Reactor) is a batch-operated biological wastewater treatment process. Unlike a continuous activated sludge system, the individual process steps are carried out sequentially over time in the same reactor.
By separating the process phases in time, the same reactor can be operated sequentially under aerobic, anoxic, and sedimentation conditions. This allows for the biologically reduced of both organic loads and ammonium and nitrogen.
An SBR reactor is a biological wastewater treatment plant in which filling, biological treatment, sedimentation, and clear water discharge take place in sequence, one after another, in the same reactor.
How does the ALMA BIO SBR work?
The ALMA BIO SBR operates in recurring biological treatment cycles. The individual phases are configured on a project-by-project basis depending on the wastewater load, treatment objective, and required nitrogen removal.
Filling
The industrial wastewater is fed into the SBR reactor and mixed with the active biomass present in the reactor.
React biologically
During the reaction phase, microorganisms break down biologically available organic substances in wastewater, thereby reducing COD and BOD.
Nitrification
Under aerobic conditions, nitrifying microorganisms biologically convert ammonium via nitrite to nitrate.
Denitrification
Through carefully controlled anoxic phases, nitrate can be biologically reduced to elemental nitrogen, thereby reducing total nitrogen.
Sedimentation
Once the biological reaction phase is complete, aeration and mixing are stopped. The biomass settles in the SBR reactor.
Drain the clear water
After the sedimentation phase, the biologically treated clear water is carefully withdrawn from the reactor above the settled biomass.
Remove excess sludge
A portion of the biomass is specifically removed in order to maintain the sludge age and biomass concentration within the desired operating range.
Advantages of the SBR Process
By controlling the timing of the individual process phases, an SBR combines several biological and hydraulic functions in a single reactor and can be flexibly adapted to industrial wastewater conditions.
Multiple process steps in a reactor
Biological treatment, sedimentation, and clear water discharge take place in the same tank. This eliminates the need for a separate conventional secondary clarifier.
Flexible Process Management
Aeration, mixing, sedimentation, and discharge phases can be adjusted depending on the actual hydraulic and biological load.
Good for fluctuating loads
Variable cycle control is particularly suitable for industrial wastewater with fluctuating flow rates, production times, or organic loads.
CSB and Nitrogen Removal
By combining aerobic and anoxic reaction phases, organic loads, ammonium, and total nitrogen can be biologically reduced.
Compact plant design
Since multiple process functions are combined in a single reactor, the plant design can be simplified compared to multistage continuous biological systems.
Automated Operation
Inlet, aeration, mixers, sedimentation, clear water discharge, and sludge discharge can be automatically controlled based on defined process and cycle conditions.
Case Studies in Aerobic Biological Wastewater Treatment
Sugar Industry, Pemuco, Chile
Nitrification and denitrification with integrated degassing and sedimentation for a wastewater flow rate of 120 m³/h.
Abraham Benelux S.A., Belgium
Compact biological wastewater treatment plant in a container design with a capacity of 35 m³/d.
Paper mill, Southern Germany
Removal of biologically difficult-to-degrade COD via biofiltration at a flow rate of 700 m³/h.
Sugar Industry, Germany
Anaerobic treatment and aerobic post-treatment for 220 m³/h from the sugar industry.
Dairy, process water, Germany
Biofiltration for further COD removal in the water reuse process, designed for 600 m³/d.
Top Harvest Yanchang Coal, China
Biological wastewater treatment for 1,500 m³/h with an upstream DAF stage for the pretreatment of refinery wastewater.
SBR Cycle – Crucial for Biological Treatment Performance
The performance of an SBR reactor is largely determined by the division and duration of the individual cycle phases. For this reason, a fixed standard cycle is not used. The process phases are tailored to each specific project based on the wastewater load, influent profile, and required effluent quality.
Typical Factors Affecting the SBR Cycle
- Flow Rate
- CSB and BSB Loading
- Ammonium load
- Desired nitrogen removal
- Wastewater Temperature
- Oxygen demand
- Sedimentation Properties of Biomass
- Desired flow rates
- Production and Load Profiles
- Available Reactor Volumes
The key factor is not achieving the shortest possible cycle time. The key factor is a process design in which biological COD removal, nitrification, denitrification, and sedimentation are allowed sufficient time, while at the same time the required wastewater throughput is achieved.
CSB, Ammonium, and Nitrogen Removal in the SBR
The temporal separation of aerobic and anoxic reaction phases makes it possible to specifically combine different biological processes within the same SBR reactor.
CSB and BSB Degradation
During the biological reaction phase, heterotrophic microorganisms break down biologically available organic carbon compounds, thereby reducing the COD and BOD loads in the wastewater.
Nitrification
Under conditions of adequate oxygen supply, ammonium is biologically oxidized by nitrifying microorganisms via nitrite to nitrate.
Denitrification
During specifically controlled anoxic phases, nitrate can be biologically reduced to elemental nitrogen; this allows for combined nitrogen removal within the SBR cycle.
When is an SBR reactor particularly suitable?
The ALMA BIO SBR is particularly well-suited for industrial wastewater applications in which inflow, load, or production times fluctuate and flexible biological process control is required.
SBR or continuous activated sludge process?
Both processes use suspended microorganisms for biological wastewater treatment. The main difference lies in the spatial or temporal separation of the individual process steps.
| Criterion | SBR | Continuous activated sludge process |
|---|---|---|
| Mode of operation | Discontinuous / cyclical | Continuously |
| Biological reaction | In the SBR reactor | In the aeration tank |
| Sedimentation | In the same reactor | Separate Secondary Clarification |
| Clear Water Drain | Time-controlled | Continuous Process |
| Nitrification / denitrification | Controllable via cycle phases | About spatially separated process zones |
| Fluctuating Loads | High flexibility thanks to customizable cycles | Continuous Hydraulic Operation Control |
| Process control | Very flexible in terms of time | Continuous Process Control |
| Asset Structure | Multiple Functions in a Reactor | Often multiple tanks or process stages |
The main difference between SBR and a conventional activated sludge process is that, in SBR, biological treatment and sedimentation take place sequentially in the same reactor.
SBR or MBBR—which biological process is best for which situation?
SBR and MBBR are both established processes for biological wastewater treatment, but differ significantly in terms of biomass retention, operating mode, and solids separation.
SBR
In a sequencing batch reactor, the biomass is predominantly present as suspended activated sludge. Biological reaction, sedimentation, and clear water discharge occur sequentially within the same reactor.
MBBR
In a moving-bed biofilm reactor, a significant portion of the biomass grows as a biofilm on freely moving plastic carriers. The removed biomass is then separated via a separate solids separation process.
When is each method particularly useful?
Have an SBR system designed:
Maksim Neubauer
Head of International Project Development
Automated Process Control of the ALMA BIO SBR
Automation is particularly important in SBR systems, as the filling, biological reaction, sedimentation, clear water discharge, and sludge management must be reliably coordinated. The ALMA BIO SBR is designed on a project-specific basis for wastewater volumes ranging from 50 to 1,000 m³/d and is operated automatically.
Flow Control
The filling process is controlled based on the cycle status, fill level, and available reactor volume.
Oxygen measurement
The oxygen concentration is an essential basis for regulating the aerobic biological reaction phases.
Ventilation Control
The air supply can be automatically regulated based on the biological load and current oxygen demand.
Agitator Control
During anoxic phases, the biomass is mixed, without specifically introducing additional oxygen.
Clear Water Drain
After the sedimentation phase, the biologically treated clear water is withdrawn in a controlled manner from the upper reactor zone .
Sludge Management
Excess sludge removal can be automatically adjusted based on sludge age, biomass concentration, and plant operation .
Process Data & Analysis
Cycle times, oxygen levels, feed rates, operating states, and alarms can be displayed and analyzed in the control system.
Technical Specifications of the ALMA BIO SBR
The ALMA BIO SBR is a custom-designed biological wastewater treatment plant for industrial wastewater flows ranging from 50 to 1,000 m³ per day. Reactor volume, cycle control, aeration, mixing, and automation are all tailored to the wastewater load and the required effluent quality.
| Parameters | Design |
|---|---|
| Procedure | Sequencing Batch Reactor (SBR) |
| Hydraulic power | 50–1,000 m³/day |
| Mode of operation | Discontinuous / cyclical |
| biomass | Suspended activated sludge |
| Stages of the Process | Filling, Reaction, Sedimentation, Clear Water Discharge and Sludge Discharge |
| Biological Objectives | CSB/BSB Removal, Nitrification, and Denitrification |
| Ventilation | Diaphragm aerators or tube aerators, designed specifically for each project based on oxygen requirements and reactor geometry |
| Mixing | Submersible mixer, central mixer, or side-mounted mixers, depending on reactor size and process control |
| Clear Water Drain | Automated clear water discharge after sedimentation |
| Measurement | O₂, pH, redox; optional: COD, NH₄-N, NO₂-N, NO₃-N |
| Automation | Automatic Cycle and Process Control |
| System Integration | New and Existing Facilities |
Typical industrial applications
SBR systems are particularly well-suited for industrial wastewater containing biodegradable organic pollutants, varying inflow conditions, or requirements for biological nitrogen removal.
Food industry
Biological treatment of organically contaminated production wastewater with fluctuating levels of COD and BOD loads.
Beverage Industry & Breweries
Treatment of highly biodegradable industrial wastewater with varying production and treatment cycles.
Dairies
Biological treatment of wastewater with high organic loads characterized by significant fluctuations in production and load.
Chemical industry
Treatment of suitable biodegradable sub-streams following pretreatment tailored to the water chemistry.
Pharmaceutical & cosmetics industry
Flexible biological treatment of intermittent biodegradable production wastewater.
Decentralized Wastewater Treatment
Compact biological treatment at sites with intermittent wastewater generation or limited infrastructure.
What data do we need for the SBR design?
When designing an SBR reactor, in addition to the daily wastewater flow rate, the following factors are particularly relevant: the temporal inflow profiles, biological loads, nitrogen load, and the required effluent parameters.
Key Data for the Initial SBR Design
- Average and Maximum Wastewater Generation
- Daily and Weekly Quantities
- Inlet Profiles
- CSB and BSB
- Biodegradable COD
- Ammonium nitrogen
- Total nitrogen
- Phosphorus
- pH value
- Wastewater Temperature
- Solids content
- Production Times
- Peak loads
- Desired flow rates
- Existing Pretreatment
- Known Inhibitors
- Existing pool or available installation space
Based on wastewater volume, analysis, influent profile, and effluent requirements, we design the reactor volume, cycle control, aeration, and necessary biological process stages on a project-specific basis.
Photos of aerobic wastewater treatment plants
FAQ - ALMA BIO SBR Sequencing Batch Reactor
What does SBR mean in wastewater treatment?
SBR stands for Sequencing Batch Reactor. In this process, the individual steps of biological wastewater treatment are carried out sequentially in a single reactor. Typical phases include filling, biological reaction, sedimentation, clear water discharge, and excess sludge removal.
For which types of industrial wastewater is an SBR particularly suitable?
An SBR is particularly well-suited for biodegradable industrial wastewater with fluctuating volumes or load levels. Typical applications include, for example, the food, beverage, dairy, chemical, pharmaceutical, and cosmetics industries, as well as decentralized wastewater treatment plants.
Can an SBR be operated even when wastewater is generated intermittently?
Yes. The SBR’s cyclic operation can be particularly advantageous when wastewater is generated in batches or at irregular intervals. This allows the inflow and reaction phases to be adjusted to production schedules and actual wastewater volumes.
Does an SBR require a separate secondary clarification stage?
Generally not. In SBR systems, the biomass settles directly in the reactor. After the settling phase, the treated clear water is withdrawn in a controlled manner from above the settled sludge. This eliminates the need for a separate, conventional secondary clarification process.
How is the cycle time of an SBR determined?
The cycle duration is determined on a project-by-project basis based on wastewater volume, organic load, nitrogen load, temperature, sedimentation, and required effluent parameters. Therefore, there is no universally optimal standard cycle time for industrial SBR systems.
Can an existing tank be converted into an SBR reactor?
In principle, retrofitting is possible if the tank volume, geometry, and hydraulic boundary conditions are suitable. In addition, systems such as aeration, mixing, clear water discharge, measurement technology, and automation must be adapted to cyclic operation.
How flexibly can an SBR be expanded as production volume increases?
Expandability depends on the existing plant design. Depending on the available reactor volume, cycle control and operating mode can be adjusted, or additional SBR lines can be added. Therefore, potential future increases in production should be taken into account early in the design process.
What pretreatment may be necessary before an SBR?
That depends on the composition of the industrial wastewater. Depending on the application, processes such as screening, grease or solids removal, neutralization, homogenization, or chemical-physical pretreatment may be necessary. The goal is to create stable and sufficiently biodegradable influent conditions for the biological SBR stage.
Our Reactors for Aerobic Wastewater Treatment
ALMA BHU BIO
The ALMA BHU BIO System combines nitrification, denitrification, and sedimentation with biomass recirculation to increase conversion rates.
ALMA BIO BBI
The ALMA BIO BBI system is characterized by its integrated sedimenter, which makes it extremely space-saving compared to similar systems.
ALMA BAF
Biologically activated filtration (BAF) uses sessile microorganisms to remove organic compounds (BOD, COD) and nitrogen from wastewater.
ALMA BIO MBBR
Biological wastewater treatment using free-floating biofilters for the efficient reduction of carbon and nitrogen compounds.
ALMA BIO SBR
A sequentially operated bioreactor with distinct phases for biological treatment, sedimentation, and clear water discharge.
ALMA BHU BIO DEA
Biological deammonification process for energy-efficient nitrogen removal from wastewater with high ammonium content and low oxygen demand.
ALMA BIO Compact MBBR
Containerized MBBR system for biological wastewater treatment, offering high treatment capacity per unit area and rapid integration into operations.
ALMA BioFil Compact
Our compact biologically activated filtration in tank design, equipped with special growth bodies for effective biomass growth.
ALMA BIO MBR
Membrane bioreactor with submerged plate modules or an externally mounted ultrafiltration unit in a robust tubular module design.
Have an SBR system designed:
Maksim Neubauer
Head of International Project Development