IS 10261:1982 is the Indian Standard (BIS) for requirements for settling tank (clarifier equipment) for wastewater treatment. This standard specifies the requirements for the design, materials, construction, and installation of settling tanks (clarifiers) used for solid-liquid separation in wastewater treatment. It covers key design parameters like surface overflow rate, detention time, and weir loading, as well as mechanical equipment such as scraper mechanisms and drive units.
Requirements for settling tank (clarifier equipment) for wastewater treatment
BIM-relevant code. See the BIM Hub for ISO 19650, IFC, and LOD/LOIN frameworks used alongside it.
| Parameter | IS Value | International | Source |
|---|---|---|---|
| Circular Scraper Tip Speed | 2.0 to 3.0 m/min | Typically 1.8 to 3.7 m/min; not to exceed a speed that causes solids scour. | ASCE/EWRI 53-10 |
| Circular Tank Floor Slope | 1 in 10 to 1 in 12 (8.3% to 10%) | 1 in 12 (8.3%) is typical; range of 6% to 10% is common. | ASCE/EWRI 53-10, DIN 19569-2 |
| Rectangular Collector Speed | 0.6 to 1.2 m/min | Typically 0.6 m/min, should not exceed 0.9 m/min. | WEF MOP No. 8 |
| Scraper Blade Material | Mild steel or cast iron | Stainless steel, galvanized steel, GRP, or steel with replaceable elastomeric (neoprene) squeegees. | DIN 19569-2 / Common Practice |
| Drive Torque Design Basis | Motor power selected from a table based on tank diameter. | Calculated based on a torque formula (e.g., T = K * D²) with safety factors for peak loads. | WEF MOP No. 8 |
| Drive Unit Overload Protection | Torque indicating device is required. | Requires a calibrated torque sensor with adjustable alarms (e.g., at 75% max torque) and automatic shutdown (e.g., at 100% max torque). | DIN 19569-2 |