01 What Happened

A peer-reviewed open-access study published on August 24 evaluated a two-stage system using babassu-coconut biochar followed by ceramic microfiltration for real produced water from the Rabo Branco oil field in Sergipe, Brazil. The biochar had a BET surface area of 304.79 m²/g. Oil and grease decreased from 429.8 to 9.8 mg/L after biochar treatment, while final turbidity removal reached 99.88–99.99%. The authors reported stable membrane flux around 210–220 L/m²·h. Salinity and conductivity, however, declined by only about 9–12%.

02 Key Takeaways

  • 01 The study used real produced water rather than a synthetic emulsion.
  • 02 Biochar substantially reduced oil loading before the ceramic membrane and supported stable flux.
  • 03 The system is effective for de-oiling and solids control but is not a desalination process.

03 Why It Matters

The most useful result is not that the hybrid system removed oil; it is that the biochar reduced the contaminant load reaching the ceramic membrane and helped stabilise flux.

04 ATLAS Engineering View

Oil and grease fell from 429.8 mg/L to 9.8 mg/L after biochar pretreatment, while the membrane stage operated around 210–220 L/m²·h. This makes biochar function partly as an adsorbent and partly as a sacrificial fouling-control layer.

The limitation is equally important. Conductivity and salinity fell only about 9–12%, and total solids only about 10–13%. The process therefore addresses de-oiling, colloids and membrane fouling far more effectively than dissolved salts. If the reuse target requires low-TDS water, a downstream desalination step such as NF, RO, ED or thermal treatment would still be needed. De-oiling is not desalination.

05 Sources