Analysis of hydraulic conditions and HRT on the basis of experiments and simulations on soil column

Salah Jellali*, Talel Sediri, Hamadi Kallali, Makram Anane, Naceur Jedidi

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

4 Citations (Scopus)


The hydraulic residence time (HRT) is a key parameter affecting the soil aquifer treatment process (SAT) efficiency as tertiary treatment of wastewater through infiltration in vadose zone. In order to maximize the HRT, a pulsed feeding technique of a salt solution (used as conservative tracer) was adopted to allow the increase of HRT and soil aeration between pulses. For this reason, several laboratory column experiments combined with the use of a numerical model was conducted. The optimal number of pulsations that meet with the maximum of the HRT and the temporal variation of the water saturation into the column was determined for different applied hydraulic heads. It varies between 10 and 12. The maximum corresponding water stock in the porous media column was evaluated to about 84%, 79% and 73%, respectively, for an applied hydraulic head of 96, 75 and 50 cm. The applied hydraulic head had an important effect on the HRT. In fact, this parameter varies from almost 6.5 to 10.8 h for an applied hydraulic head of 96 and 50 cm. The change in the permeability of the soil had also a significant effect on the HRT. Hence, HRT is decreased of about 9% when the soil permeability at saturation is multiplied by 2, and increases of about 11% when the permeability is two times lower.

Original languageEnglish
Pages (from-to)435-443
Number of pages9
Issue number1-3
Publication statusPublished - Sept 30 2009
Externally publishedYes


  • Hydraulic residence time
  • Numerical modelling
  • Soil aquifer treatment

ASJC Scopus subject areas

  • General Chemistry
  • General Chemical Engineering
  • General Materials Science
  • Water Science and Technology
  • Mechanical Engineering

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