Two New CIWEM Books Released

‘Biological & Submerged Aerated Filters’ by H. Rundle 
The author, now an independent consultant, with expertise in wastewater strategic planning and a  speciality in modern treatment technologies for municipal and industrial wastewaters particularly filtration technologies.  He has been responsible for the process design, commissioning and operation of several BAF installations and for the development of a modern SAF process which has a large number of installations worldwide. 

This handbook covers Biological Aerated Filters (BAFs) and Submerged Aerated Filters (SAFs) processes used in wastewater treatment.  BAFs are submerged biofilm reactors in which biological and suspended solids removal are carried out in the same reactor. SAFs are submerged biofilm reactors in which only biological oxidation is carried out.  

The author describes the commercially available processes in the UK trying to avoid the book becoming a “buyers guide” to BAFs and SAFs.  BAFs have been discussed in generic types (upflow/downflow, floating/sunken media etc) without using trade names.  The main points of each type have been discussed.  It is also vital to remember that BAF and SAF form only one part of the process flowsheet.  Not only do the processes themselves have various components (e.g. media, flow distribution, backwash and process air systems) but they are also affected and affect other parts of the flowsheet (e.g. screens, backwash returns etc.).  

‘Natural Wastewater Treatment’ by D. D. Mara 
The author is now professor of Civil Engineering at the University of Leeds, it was whilst he was a lecturer at the University of Nairobi that his interest in natural wastewater treatment began.  Later as visiting professor in Brazil he co-directed a major research programme on waste stabilization ponds.  Prof. Mara current research topics are the development of high rate anaerobic ponds and rock filters and microbial analysis applied to wastewater use in agriculture and aquaculture.  

This handbook that discusses in detail the construction and running of natural wastewater treatment practices as well as their advantages and disadvantages in different sites. The treatments described include:  septic tanks, constructed wetlands, waste stabilization ponds and rock filters plus a chapter comparing benefits and costs of these options.