Exploring Forward Osmosis Systems for Recovery of Nutrients and Water

Livestock wastewater contains a large amount of nutrients that are available for recovery. In this study, a proof of concept process based on forward osmosis (FO) was proposed and investigated for in-situ formation of struvite from digested swine wastewater. This FO system took advantage of a drawback reverse solute flux (RSF) and used the reversed-fluxed Mg^{2+} for struvite precipitation, thereby accomplishing recovery of both water and nutrient. With 0.5 M MgCl2 as a draw solution, high purity struvite formed spontaneously in the feed solution and the water flux through the FO membrane reached 3.12 LMH. The precipitated struvite was characterized and exhibited a similar composition to that of commercial struvite. The FO system achieve >50% water recovery, >99% phosphate recovery (given sufficient magnesium supply), and >93% ammonium nitrogen removal from the digested swine wastewater. The recovered products (both struvite and water) could potentially generate a value of 1.35 $ m^{-3}. The results of this study have demonstrated the feasibility of nutrient recovery from livestock wastewater facilitated by FO treatment.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Environmental Engineering

Department dc:contributor.department

Environmental Sciences and Engineering

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

2018

Author dc:creator

• Wu, Zhenyu

Chair dc:contributor.committeechair

• He, Zhen

Committee members dc:contributor.committeemember

• Wang, Zhiwu
• Dietrich, Andrea M.

• Forward osmosis
• Swine wastewater
• Struvite
• Nutrient recovery
• Water recovery

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Dc Identifier Other

vt_gsexam:14295

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/81881