## What is standard rate trickling filter?

Standard rate trickling filters are normally designed for hydraulic ratings of 1.1 to 4.3 m3/m2/d and organic loadings of 0.08 to 0.41 kg BOD/m3/d. These filters are normally 1.8 to 2.4 m deep and rectangular or circular in shape.

## What is high rate trickling filter?

High-rate trickling filters are similar to conventional or standard trickling filters except that the rate of loading (both hydraulic as well as organic) for high rate filters is several times more than that for conventional trickling filters.

**What is percentage of waste water in trickling filter?**

The microorganisms absorb the organic matter in the sewage and stabilize it by aerobic metabolism, thereby removing oxygen-demanding substances from the sewage. Trickling filters remove up to 85 percent of organic pollutant from sewage.

**How do you determine hydraulic loading rate of a trickling filter?**

The hydraulic loading rate is calculated based on filter surface area. The normal hydraulic loading rate ranges for standard rate and high rate trickling filters are: Standard rate: 25 – 100 gpd/ft2 and High rate: 100 – 1000 gpd/ft2. Trickling filters are sometimes classified by the organic loading rate applied.

### What is the design criteria for trickling filter?

The trickling filter design must evaluate the impacts of recirculation, air draft temperatures and medium. Recirculation capability is required for all variations of the trickling filter process except roughing filters provided that minimum hydraulic loading rates are maintained at all times.

### How do you calculate the efficiency of a trickling filter?

Overall Efficiency of Two Stage Trickling Filter is the total efficiency obtained after the waste passes from 2 filters and is represented as E = (Qi-Qo/Qi)*100 or Overall efficiency TF = (Influent BOD-Effluent BOD/Influent BOD)*100.

**What are the types of trickling filters?**

There are gennerally three types of filter media including rock (or slag), redwood, and synthetic materials. Rock is the original media used in trickling filters.

**How do you determine organic loading rate of a trickling filter?**

To calculate the organic loading on the trickling filter, two things must be known: the pounds of BOD or COD being applied to the filter media per day and the volume of the filter media in units of 1000 cubic feet. The BOD and COD contribution of the recirculated flow is not included in the organic loading.

#### What is design loading rate?

You can calculate loading rates with a few basic steps. Calculate the hydraulic loading rate with the formula: Hydraulic loading rate = Design flow (gal/day) / Area (feet ^2). Design flow is the volume of waste water per day.

#### What are the various factors affecting the operation of trickling filter?

Important factors affecting removal efficiency are assumed to be the same as the factors that affect performance for organic matter removal and include:

- Hydraulic and organic loading rate.
- Distribution system efficiency.
- Media clogging.
- Recirculation ratio (trickling filters)
- Hydraulic retention time (anaerobic filters)

**What is recirculation factor in trickling filter?**

Recirculation Factor: Recirculation ratio is the ratio of recirculated flow to the total flow of raw sewage. The capacity of the pumps doing the recirculation of sewage is determined with this. The increased load on the trickling filters is also determined by this. = (1+ Recirculation Ratio).

**What is the recirculation ratio?**

The recirculation ratio is the amount of wastewater that flows through the advanced pretreatment component divided by the amount of wastewater that is sent to the final treatment and dispersal component.