Bioaugmentation is a practise that works to enhance the performance of the biological treatment plant by increasing the number of microorganisms with the desired characteristics that are directly involved in biodegradation and breakdown process of the chemical compounds present in the wastewater. Usually in a pool of indigenous bacterial population, there are usually presence of different types of microorganisms like for example the filamentous bacteria and the whole purpose of implementing a bioaugmentation program is to out compete the unwanted bugs so that a healthy and efficient biological system is in place.
Biological treatment plant can encounter a lot issues that can affect its performance and few of the major causes are directly related to the factors which are often difficult to control or sometimes unavoidable and thus presents a great challenge to the operation team. Most of the causes that can upset the plant are mostly related the changing influent characteristics such as BOD/COD overload, hydraulic overload due to unexpected high amount of generation of wastewater, extreme fluctuation in BOD/COD value that can cause sudden shock and the most notorious and difficult to handle is the intoxication of waste materials. Other than the influent factor, sometimes equipment breakdown, nutrient deficiency, environmental problems such as pH fluctuation, temperature going out of range and mishandling by the operators can all contribute towards the microbial imbalance.
Let’s look at the chart above which represents on how the whole bioaugmentation process works. As you can see here, Population A is the working bacteria while Population B represents a portion of the unwanted strains which overall do not contribute to the efficiency and operation of the biological system and the worst part is that they will compete with those other strains and consume the valuable nutrients and oxygen content as well. The pie chart on your left shows the breakdown of bacterial population that represents the overall pool of microorganisms that comprises both the desirable and unwanted strains of bugs while the chart on your right is after the bioaugmentation program has been implemented. From here, the percent population of the desired strains has increased due to the new introduction. As a result, what you have is a bio system which is more robust, increased microbial activity and overall more capable to handle the effects caused by influent fluctuation.
Why Needs it and the Benefits
Bioaugmentation is often seen as a solution that overcomes some of the most common wastewater treatment plant problems. From the list shown here, there are at least 5 examples that detail out some of the most feared crisis often plaguing the operation team.
- Sludge bulking issue which causes poor settling characteristic of the biomass
- High percentage of total suspended solids in the effluent
- Excessive and heavy foaming in the aeration basin which spirals out of control
- Low effluent pH caused by the microbial activity affecting the discharge quality
- Inefficient waste breakdown leading to high BOD/COD effluent not meeting the regulation standards
With the new development and improved technology, bioaugmentation is often seen as the best solution to overcome problems related to non-compliance discharge. The same approaches are most applied toward petrochemical waste handling. The benefits of the bioaugmentation products are:
- High microbial activity with fast growth rate so that results can be quickly achieved in a matter of days
- High survival rate of the microbial strain to become the dominant population so that the positive effect is still shown even after months or years
- Industrial specific meaning that a specific strain is made specially for certain types of waste materials
- Easy to use so that the product could be directly introduced to the waste influent or directly to the aeration basin (depending on situation, sometimes the bio culture has to be rehydrated prior to use)
- Saves additional wastewater management cost during plant upset whereby additional storage tanks has to be sourced for holding the incoming waste and to divert the non-compliance discharge for temporary storage while waiting for the system to recover
- Avoids third party involvement as bioaugmentation can be done in-house by trained personnel
- Avoids total breakdown of the main processing plant and production lines because the wastewater system is unable to handle additional hydraulic load during the upset period
Implementation methodology
The whole process setup can be represented by the step-by-step flow chart shown below.
Problems affecting biological system
Study the problem, review the system and collect data
Design and implement traceability study
Develop and execute the program
Monitor results and measure the effectiveness
The whole process setup can be represented by the step-by-step flow chart shown below.
Problems affecting biological system
Study the problem, review the system and collect data
Design and implement traceability study
Develop and execute the program
Monitor results and measure the effectiveness
Overall, bioaugmentation is also seen as cost-effective method compared to treatment plant upgrading. Furthermore, since it only involves re establishing or introduction of the specific strains of bacteria, it does not need major adjustment to be done on the process or any other complicated project development. Read also on how bioaugmentation is applied in UASB Reactors.