Mechanism of virus removal and nutrient reduction and modification of bio-sand filter

The objectives of this study were to assess the role of nitrate and ammonia concentrations in the feed water on the removal of bacteriophage MS2 using bio-sand filters (BSFs) and analyze the formation of the bacterial community in BSFs, and modify BSFs with different packing materials and structures. Five bench-scale BSFs were constructed from 4 inches PVC. Two BSFs were fed with high and low nitrate concentrations (50 mg/L and 4mg/L), while the other two BSFs were fed with high and low ammonia concentrations (35 mg/L and 4mg/L). The fifth column was fed with 0.5 mM of bicarbonate buffer and used as the control. The MS2 bacteriophage removal tests were conducted, and effluent was also analyzed for nitrate and ammonia. Also, the influent water chemistry was altered to simulate the seasonal change in feed water conditions. The bacterial communities developed inside these filters were analyzed based on the sequences of the 16S rRNA genes and using ammonia-oxidizing bacteria primers. It was observed that BSFs were able to remove MS2, ammonia to a certain degree but not nitrate. In order to improve nitrate removal in BSF, three bench-scale BSFs were constructed from 3 inches PVC, packed with different proportions of woodchips and sand, and fed with high nitrate concentration (50 mg/L). The proportions of sand and woodchip were different such as 50% of woodchip and sand (filter B), 70% of woodchip and 30% of sand (filter A), and 100% woodchip and 5cm sand layer (filter A’). The results indicated that higher MS2 and nitrate removal could be achieved by using the modified woodchip amended BSFs. The filtration depth was increased by connecting the modified BSF to the conventional BSF, and the different flow direction was also considered. The sequencing of 16 rRNA genes was conducted to analyze the bacterial community in BSFs. These results suggest that the concentrations of nutrients in the feed water can influence the biofilm growth inside BSFs and can have a significant impact on virus removal.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Agricultural & Biological Engr

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2020

Author dc:creator

• Jang, Chunhwa

Contributors dc:contributor

• Bhattarai, Rabin
• Nguyen, Thanh H.
• Cooke, Richard A.
• Men, Yujie

• Biosand filter
• Biofilm
• MS2 removal
• Ammonia and Nitrate removal

Statement dc:rights

• Copyright 2020 Chunhwa Jang

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/108233

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/108233