Recommendations
UASB check-list: hydraulic parametersSolid Liquid Sedimentation AECIUASB reactor: volume determinationUASB reactor: plan area and depthHead loss coefficient applicable to partially open y valveBasic data for a wastewater treatment plant design

UASB cylindrical D = 2,40 m; V = 23,28 m³

Input data

Average flow

Maximum flow

Output data

Hidraulic detention time for average flow

Description

Given the average and maximum flow to be treated, calculates the hydraulic detention time for the average flow, the upward velocities in the interior of the reactor and the velocity at the passage from the digesting to the settling compartment, allowing to compare the obtained results to the recommended parameters proposed by the Brazilian Standard ABNT NBR 12209:2011.

cylindrical UASB reactorcylindrical UASB reactor

Notes

  1. Recommendations for the hydraulic detention time corresponding to the average flow, depending on the temperature (NBR12209:2011):
  • 1.1. 6 h for sewer temperatures above 25°C
  • 1.2. 6 h for sewage temperatures between 22°C and 25°C
  • 1.3. 6 h for sewage temperature between 18°C ​​and 21°C
  • 1.4. 10 h for sewage temperatures between 15°C and 17°C
  1. Recommendations for the rising speed in the reactor digestion compartment:
  • 2.1. Equal to or less than 0.7 m/h for the average flow
  • 2.2. less than 1.2 m/h for maximum flow
  1. Recommendations for the speed of passage from the digestion compartment to the decantation compartment:
  • 3.1. Equal to or less than 2.5 m/h for the average flow
  • 3.2. less than 4 m/h for maximum flow

References

  • ABNT. NBR 12209 - Elaboração de projetos hidráulico-sanitários de estações de tratamento de esgotos sanitários. Rio de Janeiro: ABNT, 2011.