Simulation of Activated Carbon Reactors

What are the benefit of hydrograv simulations?

  • proof of the flow conditions and improved mixing and hydraulic residence time
  • efficient dimensioning of agitators
  • prevention of depositions
  • maximization of separation in the settling tank

Example 1: Measurement of settling velocities

  • investigation of sludge properties
  • settling tests
  • calibration of the settling models

Figure:   Comparison between measured and simulated settling velocities.

Example 2: Simulation of a contact reactor with inner settling tank

  • optimization of mixing in the reactor
  • maximization of particle separation in the settling tank

Figure:   Flow velocities in the contact reactor designed as a ring-shaped tank.

Figure:   Concentration of a mix of activated carbon and activated sludge in a settling tank. Illustration on a vertical plane.


Example 3: Optimization of a contact reactor

  • optimization of the number of agitators, the agitator’s thrust and their orientation
  • installation of deflection baffles
  • minimization of depositions
  • minimization of the energy consumption for mixing
  • proof of different loading cases: the preferred variant is the best compromise between dry weather and stormwater flow

Figure:   Distribution of particles as normalized mass fraction.

Figure:   Velocities close to the bottom as proof for depositions.

Figure:   Deterministic analyses of the velocities close to the bottom as proof for depositions.

Figure:   Statistical analyses of a tracer simulation, here showing the 10 %-percentile as proof for short-circuit flows.