Trickling filter design guideline – How do trickling filters work?

Trickling filters are biological reactors within wastewater treatment plants which are used to remove organic matter and/or ammonia from wastewater. Compared to the activated sludge process the microorganisms are not suspended in the mixed liquor but they are attached to a fixed bed surface. Nowadays, the fixed bed surface is usually provided by structured plastic fill media but in the past rock, gravel and hardwood was also used. 

Watch the video tutorial here.