|Sourcebook of Alternative Technologies for Freshwater Augmentation in East and Central Europe (UNEP-IETC, 1998)|
|Part B - Alternative technologies|
|3. Wastewater treatment technologies and reuse|
The technology usually includes, as principal phases, the gravity separation of tars and oils, ammonium stripping, and a two stage biological purification process to remove especially phenols and sulphocyanides. Possible modifications of the technology could include breaking down colloids by cationic polyelectrolyte treatment, improved removal of phenols by introducing of a biooxidation phase, and ozone treatment for the removal of traces of cyanide and colour (the ozonation technology is described above). Pretreatment with bleaching earth is recommended prior to ozonation to minimize the amount of ozone required.
Extent of Use
This technology has been applied in Romania.
Operations and Maintence
This technology makes use of readily available wastewater treatment components, including biofilters, ozone production plant, and measurement and control equipment, and commonly available reagents such as cationic polyelectrolytes. The system requires moderately skilled staff to operate.
Level of Involvement
The technology is usually implemented at the local and/or community level. However, due to the cost of the equipment, (partial) external financing may be necessary.
The cost of this technology is approximately $3 to $5.5 million, depending on import requirements and the size of the plant.
Effectiveness of the Technology
The technology is highly efficient and produces an effluent of consistent quality, which meets or exceeds the Romanian quality requirements for discharge into surface rivers in the III-rd category. Pilot scale plants of 5 m³/h capacity are in operation and a 135 m³/h capacity industrial plant is being completed.
The technology has been developed for application in the treatment of wastewater from the coking industry, although other applications may be possible using modifications of this technique.
This technology is well suited for treating complex wastewaters contaminated with tars, oils, phenolic compounds, ammonium, sulphocyanides, cyanides, and other pollutants that are difficult contaminants to treat using traditional wastewater treatment methods.
There are no known disadvantages.
This is a acceptable wastewater treatment technology.
Further Development of the Technology
The technology is fully developed.
ICPEAR (Institutul de Cercetari pentru Epurarea Apelor Reziduale - Research Institute for Waste Waters Treatment), Sos. Pandrui nr 90-92, sector 5 Bucuresti, COD 76231, Romania, Tel./fax: (40-1) 410 67 16.