Strengthening aerobic granule by salt precipitation

Yu-You Chen; Xiangliang Pan; Jun Li; Duu-Jong Lee

doi:10.1016/j.biortech.2016.06.111

Strengthening aerobic granule by salt precipitation

Bioresour Technol. 2016 Oct:218:1253-6. doi: 10.1016/j.biortech.2016.06.111. Epub 2016 Jun 29.

Authors

Yu-You Chen¹, Xiangliang Pan², Jun Li², Duu-Jong Lee³

Affiliations

¹ Department of Chemical Engineering, National Taiwan University, Taipei 106, Taiwan.
² College of Environment, Zhejiang University of Technology, Hangzhou 310014, China.
³ Department of Chemical Engineering, National Taiwan University, Taipei 106, Taiwan; College of Environment, Zhejiang University of Technology, Hangzhou 310014, China. Electronic address: djlee@ntu.edu.tw.

PMID: 27377228
DOI: 10.1016/j.biortech.2016.06.111

Abstract

Structural stability of aerobic granules is generally poor during long-term operation. This study precipitated seven salts inside aerobic granules using supersaturated solutions of (NH4)3PO4, CaCO3, CaSO4, MgCO3, Mg3(PO4)2, Ca3(PO4)2 or SiO2 to enhance their structural stability. All precipitated granules have higher interior strength at ultrasonic field and reveal minimal loss in organic matter degradation capability at 160-d sequential batch reactor tests. The strength enhancement followed: Mg3(PO4)2=CaSO4>SiO2>(NH4)3PO4>MgCO3>CaCO3=Ca3(PO4)2>original. Also, the intra-granular solution environment can be buffered by the precipitate MgCO3 to make the aerobic granules capable of degradation of organic matters at pH 3. Salt precipitation is confirmed a simple and cost-effective modification method to extend the applicability of aerobic granules for wastewater treatments.

Keywords: Salt; Sequential batch reactor; Stability; Strength.

MeSH terms

Bioreactors*
Sewage / chemistry*
Sodium Chloride / chemistry*
Wastewater / chemistry*

Substances

Sewage
Waste Water
Sodium Chloride