PVA Gel Bioreactor


  • 1. Excellent fluidity in water requiring minimal energy for mixing.
  • 2. PVA gel has a network of minute pores about 20 microns in diameter tunneling throughout each bead.
  • Effective bacteria can be enriched in large numbers in the protective core of the beads,
    thus greatly reducing sloughing of biomass.
  • While maintaining stable treatment efficiencies. Good oxygen permeability can support a high loading.
  • Therefore even with a low filling ratio PVA gel has high treatment power.
  • 【Load】
  • Up to 50 kg・BOD/㎥・gel・d (BOD Removal)
  • 6 kg・N/㎥・gel・d (Nitrogen Removal)
  • 3. Treatment with PVA gel yields less excess sludge as compared to conventional biological methods.
  • 4. PVA gel has a very high water content due to its extensive porosity, thus allowing for favorable permeability of oxygen and nutrients to the bacteria colonized inside the beads.
  • 5. Polymerized PVA gel is essentially insoluble in water and is not known to be biodegradable.
  • 6. Depending on the characteristics of the wastewater, treatment ability using PVA gel can be enhanced up to 5 times over that of conventional activated sludge, thus allowing for upgrading of existing overloaded systems or for design of new process units with greatly reduced foot prints.


  • Material: PVA (Polyvinyl alcohol)
  • 4 mm spherical beads having a specific gravity of 1.025.
  • One PVA-gel bead can hold up to 1 billion microorganisms. *
  • (* depending on operating conditions)

Distribution of Bacteria

  • Fluorescence in situ hybridization (FISH) method
  • Bacteria multiply toward the core of PVA-gel beads.

Anammox bacteria attached a gel bead

Nitrification Bacteria attached in a gel bead

Denitrifying bacteria attached in a gel bead