Advanced treatment solutions intended for the reuse of livestock wastewater in agricultural applications

One of the main concerns of the developing world is the mitigation of pollution of environmental components together with the recovery and reuse of valuable substances from waste resulting during diverse anthropic activities. Wastewater generated by agro-zootechnic activities is a source of nutrients (nitrogen and phosphorus compounds) and traditionally it is reused for crops irrigation. However adverse effects on the environment may be caused should a proper treatment not be performed, considering the spread of additives/drugs altering the natural metabolism in modern livestock industries and subsequently their presence in waste. In this context, research was conducted on laboratory scale setups of some advanced treatment processes for wastewater resulting from cattle farms. UV disinfection and oxidation using ozone were investigated in order to emphasize the antimicrobial effect and their contribution to the improvement of water quality. The permissible irrigation water quality which varied based on the crop type was the decisive factor in adjusting the experimental setup and effluent quality. The results have revealed the inactivation of bacteriological indicators up to 99% and even 100% in the case of faecal coliforms and faecal streptococci. Moreover, ozonation allows also the removal of organic matter, with an efficiency of over 80%. This research offers solutions suitable for areas where the water demand exceeds availability and in the regions affected by drought.