Development of an integrated membrane process for water reclamation

Area of Science:

• Environmental Engineering
• Water Treatment Technologies
• Membrane Science

Background:

• Conventional wastewater treatment often struggles with recalcitrant organic compounds.
• Membrane processes like MBR and RO are effective but can generate concentrated waste streams.
• Optimizing water reclamation requires efficient removal of contaminants and resource recovery.

Purpose of the Study:

• To develop and evaluate an integrated membrane process (IMP) for enhanced water reclamation.
• To investigate the feasibility and impact of recycling reverse osmosis (RO) concentrate back to the membrane bioreactor (MBR).
• To assess the overall efficiency and product water quality of the novel IMP.

Main Methods:

• An integrated membrane process (IMP) was designed, combining MBR and RO.
• The MBR was operated at specific sludge retention time (SRT) and hydraulic retention time (HRT).
• A fraction of RO concentrate was recycled to the MBR, and performance was monitored.

Main Results:

• The IMP achieved an overall water recovery efficiency of 80%.
• Recycling RO concentrate allowed degradation of hard-to-degrade organics by acclimated biomass, improving MBR efficiency.
• An F/M ratio below 0.03 g TOC/g VSS.day in the MBR prevented biomass inhibition.
• The IMP demonstrated an average overall TOC removal efficiency of 88.940%.

Conclusions:

• The novel IMP effectively reclaims wastewater, producing high-quality reusable water.
• Recycling RO concentrate enhances MBR performance by degrading recalcitrant compounds.
• The IMP offers a sustainable solution for water reuse with high efficiency and contaminant removal.