Dear Lucio,

The attached recent review article entitled "Industrial Wastewater Treatment by Using

MBR (Membrane Bioreactor) Review Study " by Fazal et al. published in Journal of Environmental Protection, 2015, 6, 584-598 may be helpful in the assessment of  the best technology for removing persistent COD from MBR.

Hoping this will be helpful,

Rafik

Dear Rafik,

Thank you for your kind help and the very interesting paper you sent. However, I have not able to find results about field experience concerning landfill leachate treatment with MBR technology . We have analyzed this option, but no company gives guarantees for the results. Each one ask to carry on experiments at our expense. My doubts are the following :

1. We have operated also with a sludge age longer than the actual , until to 28-30 days, without no changes for effluent COD concentration;

2. If the compounds associated to the hardly biodegradable COD are stopped by the membrane, they will be accumulated in the biological reactor and can be eliminated only together with wasted sludges; so they will be recirculated with water from sludge dewatering.

Now we achieve the effluent COD reduction with ozone ,O3, but it is a very expensive treatment.

We have also ascertained that after ozone treatment the residual COD is biodegradable. So we operate a partial recirculation of the effluent. Our hope is to find an enzyme able to achieve the biodegradability for the residual COD.

Tank you again, Lucio