The Differences Between Aerobic And Anaerobic Wastewater Treatment

Out of the many steps in the collection, treatment, and release of wastewater, biological treatment is probably one of the most challenging and labor-intensive processes. There are many different forms of biological treatment available for treating wastewater, and two of the most used options are aerobic and anaerobic biological treatment. These two treatment options differ in a variety of ways, and when choosing a form of treatment it is important to know the differences.

Aerobic Treatment

Once major substances such as oil and dirt are removed from wastewater, the harmful substances dissolved into the water must then be either removed or bound to harmless elements until the individual harmful elements, such as volatile organic compounds, have been depleted to safe levels. One form of biological treatment is aerobic treatment, meaning that the harmful elements and compounds are combined with oxygen over time until they are no longer harmful. One example is this is with the air diffusion used with wastewater from fracking. This introduction of air bubbles also allows any bacteria naturally present in the wastewater to consume and adjust the harmful elements within the water, without needing to add bacteria artificially. Not all biological treatment involves adding oxygen or even having it available, however.

Anaerobic Treatment

Anaerobic treatment is a kind of biological treatment that, rather than adding or using significant amounts of oxygen, will add microbes to what needs to be treated. These microbes will essentially eat the waste and leave behind what can either be recycled (such as with sewage) or sold (such as with methane byproducts from treating feedstock). Microbe additions to feedstock are one of the best examples of this process, but it is also used with sewage treatment and many different forms of industrial sludge. This form of treatment is sometimes combined with aerobic treatments at different steps of the process as well.

There are many different steps to the process of treating wastewater and many different ways to treat it. Two popular ways, that are frequently combined together, are aerobic and anaerobic biological treatments. Aerobic treatment involves introducing oxygen to the wastewater so that it binds to the harmful chemicals in the water itself while also allowing the available microbes to better consume the waste itself. Anaerobic treatment involves introducing microbes themselves without adding oxygen. Both of these processes allow wastewater to be treated to acceptably safe levels to release back into the environment or to be reused for industrial processes.