Biological wastewater treatment systems are a big investment. When implemented correctly, they will provide your process with a lot of benefits but there can be some challenges with these systems. If your facility wants to implement biological processes of treatment of wastewater, you might wonder if there are common problems with the systems and how to avoid them. Generally, when designing, engineering and running a treatment system for your facility, issues arise during the design and operation phases. We have broken down some of the most frequently occurring challenges below.
Common design and engineering issues
Most complications with biological treatment systems occur at the design and engineering stages. It is common for systems to fall short when studies are not completed for long periods over vast amounts of data. Here are some of the design and engineering issues we encounter.
Choosing inappropriate treatment technologies
Chemical solutions might be a good selection for applications rather than implementing biological systems. We have seen this a lot when harmful components of wastewater intoxicate the useful bacteria or if there is low degradable but high non-biodegradable content. In these cases, oxidation of chemicals is normally preferred option for treatment as compared to biological. It is therefore important for water treatment specialists to look at the BOD to COD ratio to ensure that the waste is biodegradable and there isn’t much toxicity. Cheese, dairy products and whey produce biodegradable waste in which using biological wastewater treatment might be a better choice.
Inaccurate waste stream data
It is important to ensure that you gather as much information about the waste stream as possible during the beginning of the engineering process. You need to ensure that you have the right flow rates and they are accurate. Flow rates go up and down daily and they change over time in dairy and food processing facilities. Often, these facilities spend between two and three days tracking their wastewater data when they might require a thorough study. This ensures that the system engineers and designers know the average rates and are certain of the minimums and maximums over time.
There’s important information that will be factored into the design of your system and with biological treatment of wastewater, you do not just need a good facility design basis but you also need to know the necessary water pre-treatment measures. Pre-treatment could be as simple as removing solids or equalisation but you will need temperature and pH control capabilities. If these steps are not designed correctly, you will see an increase in operational problems after implementing a new system.
Not having proper aeration capabilities
When designing a biological wastewater treatment plant, it is important not to under- or over-aerate the water. If the system is anoxic or anaerobic, the design should enable your facility to create an oxygen-free environment. When the system for treatment of wastewater is under aerated, it will run out of oxygen and the first thing you will notice is foul odours. On the other hand, if you over aerate your system, it will not create operational issues but you will be running the aeration equipment unnecessarily hence wasting a lot of energy.
