What is Grit Chamber?
A grit chamber is lengthy slender tanks for slowing the flow of wastewater aiding in capturing the wastes via different screening filters
Uses |
removes inorganic solids, sand, tiny rocks. |
Other Uses |
prevents sewage clogging, protecting drainage infrastructure. |
Grit chamber types and configuration/working
Horizontal current flow grit chamber |
Canal width |
1-1.5m |
Freeboard length |
0.03m |
Adjusted space |
0.25 m |
Confinement period |
30-60 seconds |
- A canal like channel is utilized in this type of grit chamber; the length to width proportion is high to reduce the amount of mixing.
- There is not enough depth of the current here; the big waste treatment plant requires 2 or more grit chambers
Aerated grit chamber |
Detention range at flow rate |
2-5 |
Depth |
2-5m |
Length |
7.5-20m |
Width |
2.5-7 m |
Width depth ratio |
1:1-5:1 |
Length width ratio |
3:1-5:1 |
Air supply m3 / min |
0.2-0.5 |
- This chamber incorporates a blower that produces air which enters chamber by a pipe that lies at the base of the compartment itself.
- It has a good motorized design; this chamber does not require a lot of maintenance.
- It handles a good current of water flow; the particles are collected at the tank’s base.
- The aerated chamber is designed to tackle septic conditions.
Vortex grit chamber |
Detention time at flow pace |
30 |
Top chamber |
1.2-7.3m |
Lower chamber |
0.9-1.8m |
Height |
2.7-4.9m |
0.3mm Grit elimination % |
95 |
0.24mm grit elimination % |
85 |
0.15mm grit elimination % |
65 |
- Sewer water is introduced at grit chamber’s bottom, faced with continuous rotation in the bent grit chamber
- Constantly moving whizzer causes circulation and speedy rotation, resulting in the gathering of solids at the middle of the chamber, later collected in the containing tank.
- Airlift pumps shift the wastes to the organizer or the washer where they are segregated and washed
Horizontal rapidity
- The grit particles in the compartment gather down at its base, the grit chamber has different divides, such as the incoming sector, the outgoing sector.
- The incoming sector spreads the water flow to the grit compartment; the outgoing sector gathers the sewage water after the elimination of the gravels.
Handling the rapidity
There is a lot of traffic in terms of sewage that is to be processed,
- Flow rapidity is an essential factor in maintaining the current of the sewage
- When the current is slow, and the waste can get carried away, if the rapidity gets past the critical point, it will hamper the performance
Tank settling parameters
Average Primary settling overflow current |
25-30 cubic meter square meter a day |
Maximum Primary settling overflow current |
50-60 cubic meter square meter a day |
Depth |
2.5 to 3.5 |
Detention time range |
2 to 2.5 |