Biological Treatment Options

Biological Treatment Options

There are three basic categories of biological treatment: aerobic, anaerobic and anoxic.  Aerobic biological treatment, which may follow some form of pretreatment such as oil removal, involves contacting wastewater with microbes and oxygen in a reactor to optimize the growth and efficiency of the biomass.  The microorganisms act to catalyze the oxidation of biodegradable organics and other contaminants such as ammonia, generating innocuous by products such as carbon dioxide, water, and excess biomass (sludge).  Anaerobic (without oxygen) and anoxic (oxygen deficient) treatments are similar to aerobic treatment, but use microorganisms that do not require the addition of oxygen.  These microorganisms use the compounds other than oxygen to catalyze the oxidation of biodegradable organics and other contaminants, resulting in innocuous by-products.  The three individual types of biological-treatment technologies — aerobic, anaerobic or anoxic — can be run in combination or in sequence to offer greater levels of treatment.  Regardless of the type of system selected, one of the keys to effective biological treatment is to develop and maintain an acclimated, healthy biomass, sufficient in quantity to handle maximum flows and the or­ganic loads to be treated.  Maintaining the required population of “workers” in a bioreactor is accomplished in one of two general ways:

• Fixed film processes — microorgan­isms are held on a surface, the fixed film, which may be mobile or station­ary with wastewater flowing past the surface/media.  These processes are designed to actively contact the bio­film with the wastewater and with oxygen, when needed.

• Suspended growth processes — bio­mass is freely suspended in the wastewater and is mixed and can be aerated by a variety of devices that transfer oxygen to the bioreactor con­tents

It is also possible to combine both meth­ods in a single reactor for more effective treatment.


Tags: , ,

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s

%d bloggers like this: