Journal
CONSTRUCTION AND BUILDING MATERIALS
Volume 236, Issue -, Pages -Publisher
ELSEVIER SCI LTD
DOI: 10.1016/j.conbuildmat.2019.117526
Keywords
Waste concrete; Column experiment; Particle size distribution; Phosphorus removal; Mechanism
Categories
Funding
- Chongqing Scientific & Technology Committee of China [cstc2016j-cyjA0439]
- Project of State Key Laboratory of Environment-friendly Energy Materials, Southwest University of Science and Technology [17FKSY0120]
- Chunhui Program of Ministry of Education of China [z2015128]
- Yangtze Normal University research project of China [2016XJQN25]
- innovation and entrepreneurship training program for Undergraduates of Yangtze Normal University [2018ccx124]
Ask authors/readers for more resources
Reusing of fine particles of waste concrete (FPWC) is a disturbing problem for waste concrete recycling process. In this study, the FPWC developed from waste concrete was used as an innovative absorbent to remove phosphorus (P) from wastewater. The results showed, with the change of particle size of the FPWC, the maximum phosphorus binding capacity of the FPWC varies in the range of 1.07-4.96 mg P/g. The P-removal ability of FPWC increases as its particle size decreases, because of the FPWC with smaller particle size has more Ca-rich and porous hardened cement paste (HCP) powder. A components separation mechanism was proposed to explain the change of HCP powder content in FPWC with different particle size distribution. Both the Thomas and Yoon-Nelson mode' can be used to describe the P-removal behaviors of FPWC. The phosphorus removal mechanism is that the Ca2+ and OH- can release from HCP powder and forms a local alkaline condition with high Ca2+ concentration. The condition was beneficial to the formation of Ca-5(PO4)(3)(OH) which could be attached on the surface of the FPWC. Based on the Fick's law, the Ca2+ release behavior form FPWC can be separated into two stages, and it could be described by pseudo-second order model. Totally, FPWC developed from waste concrete blocks exhibited sufficient potential in phosphate removal. (C) 2019 Elsevier Ltd. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available