Removal of iron, manganese and ammonia from groundwater using a PAC-MBR system: The anti-pollution ability, microbial population and membrane fouling
2016; Elsevier BV; Volume: 403; Linguagem: Inglês
10.1016/j.desal.2016.03.002
ISSN1873-4464
AutoresXing Du, Guangyang Liu, Fangshu Qu, Kai Li, Senlin Shao, Guibai Li, Heng Liang,
Tópico(s)Wastewater Treatment and Nitrogen Removal
ResumoIron, manganese and ammonia are common inorganic pollutants in groundwater. In the current study, a powdered activated carbon-amended membrane bioreactor (PAC-MBR) was designed for the treatment of groundwater (approximately Mn2 + 1.2 mg·L− 1, Fe2 + = 15.0 mg·L− 1 and NH4+-N = 2.2 mg·L− 1). Two lab-scale PAC-MBR systems were implemented to operate for 220 d to purify three influents that had different levels of pollutants, including raw water and the effluent of conventional bio-sand filters with different dissolved oxygen levels (i.e., 9 mg·L− 1 and 6 mg·L− 1) before filtration. The results showed that an excellent MBR effluent (iron < 0.2 mg·L− 1, manganese < 0.1 mg·L− 1 and ammonia < 0.05 mg·L− 1) was obtained irrespective of the amount of pollutants, but the start-up period varied (20–49 d). With respect to the trans-membrane pressure (TMP) evolution, system I (PVDF) exhibited good performance with a slight TMP increase from 7.0 to 17.0 kPa, whereas system II (PVC) exhibited a sharp rise from 20.0 to 60.0 kPa. In brief, a cake layer containing PAC and oxides was the main reason for membrane fouling. High-throughput sequencing analysis revealed that Mn-oxidizing bacteria (MnOB) (i.e., Leptothrix, Pseudomonas, Hyphomicrobium and Planctomyces) and ammonia-oxidizing bacteria (AOB) (i.e., Nitrospira, Nitrosomonas) played major roles in the PAC-MBR systems.
Referência(s)