What is the Difference Between Activated Sludge and Trickling Filter?

🆚 Go to Comparative Table 🆚

The main difference between activated sludge and trickling filter lies in the way the biomass is cultured and mixed with the wastewater. Here are the key differences between the two wastewater treatment processes:

  1. Culturing:
  • Activated sludge is a suspended culture system, where the biomass is mixed with the wastewater.
  • Trickling filter is an attached culture system, where the biomass is grown on media, and the wastewater passes over its surface.
  1. Composition:
  • Activated sludge process consists of a series of aeration basins and a secondary clarifier, while distributors, an underdrain system, and a clarifier are used in the trickling filter process.
  1. Microorganisms:
  • In the activated sludge process, microorganisms are suspended in the mixed liquor suspended solids.
  • In the trickling filter process, microorganisms are attached to the filter medium.
  1. Space and Cost:
  • Trickling filter processes typically take up more space and are generally cheaper.
  • Activated sludge processes may require more complex infrastructure and higher costs, but they can be more suitable for smaller plants in rural areas.

In summary, activated sludge and trickling filter are both biological wastewater treatment processes that rely on microorganisms to degrade and remove pollutants from wastewater. However, they differ in the way biomass is cultured, the composition of the treatment systems, and the presence of microorganisms in the processes. The choice between these two methods depends on factors such as the available space, cost, and specific treatment requirements.

Comparative Table: Activated Sludge vs Trickling Filter

The main differences between activated sludge and trickling filter systems are their microbial growth and treatment processes. Here is a table comparing the two:

Activated Sludge Trickling Filter
Suspended culture system, where biomass is mixed with sewage Attached culture system, where biomass is grown on media and sewage passes over its surface
Aerobic basins and a secondary clarifier Circular tank, distributors, an underdrain system, and a clarifier
Rely on the formation of flocculated biomass Rely on microbial growth on media surfaces
Can produce excess sludge compared to trickling filters Stabilization of wastewater organics is an aerobic reaction, similar to activated sludge
Level of treatment that can be achieved is similar to trickling filters Used to remove organic matter from wastewater, utilizing microorganisms attached to a medium

Both activated sludge and trickling filter systems are aerobic sewage treatment methods, but they have different compositions and rely on different microbial growth processes. While activated sludge systems use suspended culture methods and rely on the formation of flocculated biomass, trickling filters are attached culture systems that rely on microbial growth on media surfaces.