Particle size distribution characterization of swine wastewater using membrane treatment process for resource recovery

Treatment of swine wastewater using membrane bioreactor (MBR) was attempted in this study, and detailed measurement of different parameters, including chemical oxygen demand (COD), total phosphorus (TP), total nitrogen (TN), ammonia nitrogen (NH4+-N) and protein, was also conducted. It has been reported that the membrane fouling phenomenon is related to the characteristics of pollutants in wastewater based on particle size distribution (PSD), therefore, clarifying the particle size range of pollutant components can help to design more efficient and targeted water treatment processes. In this article, the PSD in the swine wastewater is the primary focus, in order to select suitable membrane units for designing an advanced treatment and attaining various resource recovery. This study results revealed that the MBR influent contained majority fractions of COD, TP, and protein in both the super colloidal (accounting for 44.3%, 45.4% and 44.9%, respectively) and dissolved (accounting for 30.5%, 36.1% and 37.7%, respectively) state. Whereas, the majority of NH4+-N (72.9%) and TN (69.8%) were classified as the dissolved portion in the MBR influent. The COD and TP could be removed partly using a sedimentation unit in the particle state (>100 mu m), super colloidal state (100-0.8 mu m), and dissolved state (<0.22 mu m). MBR process, which was followed by a set of composite membranes comprised of the antifouling membrane and the desalination membrane, displayed an effective removal of TN and TP in all size ranges, especially those attributed to colloid and super colloid for all above 90% elimination abilities. The composite membranes played a vital part in the complete removal of particulate and dissolved matters. Therefore, a compensation treatment of particle and the dissolved matter was essential to wastewater disposal and to maintain a healthy water cycle. In this study, a three-dimension excitation emission matrix fluorescence spectroscopy was performed to assess dissolved humic-like substances in the filtered wastewater.