Dear Bassey, the measurement of bio-solids level in wastewater can be assessed through the value of COD and TDS. In my opinion approx. 50% of bio-solids can be removed through the stabilization pond by means of organic removal (i.e. with the help of native micro organisms) and settling. Complete removal seems to be impossible.

Certainly waste stabilization ponds are a viable, low cost, and relatively simple to operate alternatives for wastewater treatment, especially in rural areas where land is readily available, since these systems would typically have long retention times (and thus large foot prints) to achieve the desired level of treatment. I note that biosolids/sludge are by-products or residual material formed by this treatment process, not the material being treated. The disposal of bio-solids themselves can be a challenge and most often will ultimately involve land spreading, but may require stabilization and treatment to reduce vectors, pathogens etc. It is worth noting too that these treated biosolids can be a very useful soil amendment for agriculture, however it would be very important to ensure that food safety regulations would allow its use on the specific croplands involved.

In many instances only anaerobic and facultative ponds are required . In general, maturation ponds are required only when stronger wastewaters ( BOD. greater than 150 mg/l ) are to be treated prior to surface water discharge and when the treated wastewater is to be used for unrestricted irrigation ( irrigation for vegetable crops ) For mor information consult pounce.sdsu.edu

In my view stabilization ponds are for low BOD waste waters like sewage with high organic content where as for treating bio solids or sludge which is of high BOD, a huge area of land would be required. The cost of such land would be so high that one can go for the traditional anaerobic sludge digester at a low cost.

No

Dear Colleagues

Thank you so much for the responses. Please keep them coming. I would appreciate if anyone could share some field reports, relevant data and other literature to aid in my study.

Bassey