Effects of ionizing radiation on struvite crystallization of livestock wastewater

• Gamma ray was applied prior to struvite crystallization of livestock wastewater.
• Gamma ray resulted in an enhancement of struvite crystallization efficiency.
• This is due to the decrease of COD concentration by gamma ray irradiation.

Livestock wastewater is generally very difficult to be treated by conventional wastewater treatment techniques because it contains high-strength organics (COD), ammonium (NH4+), phosphate (PO43−) and suspended solids. Struvite crystallization has been recently studied for the simultaneous removal of NH4+ and PO43−. In this study, gamma ray irradiation was carried out prior to struvite crystallization of the anaerobically digested livestock wastewater. The effects of gamma ray irradiation on the struvite crystallization of livestock wastewater were investigated. As a result, gamma ray irradiation can decrease the concentration of COD, NH4+ and PO43− contained in the livestock wastewater. This results in not only an enhancement of the struvite crystallization efficiency but also a decrease in the chemical demands for the struvite crystallization of livestock wastewater.