Journal of South China University of Technology (Natural Science Edition) ›› 2017, Vol. 45 ›› Issue (5): 82-89.doi: 10.3969/j.issn.1000-565X.2017.05.012

• Architecture & Civil Engineering • Previous Articles     Next Articles

Microstructure and Chloride Ion Dissolution Characteristics of Soda Residue

YANG Yi-bo1,2 PU Yong-qiang1 YAN Wei-jun1 GUO Wen-ying1 WANG Heng-chang1   

  1. 1.School of Civil Engineering and Transportation,South China University of Technology,Guangzhou 510640,Guangdong,China; 2.State Key Laboratory of Subtropical Building Science,South China University of Technology,Guangzhou 510640,Guangdong,China
  • Received:2016-08-29 Revised:2016-12-29 Online:2017-05-25 Published:2017-04-01
  • Contact: 杨医博( 1977-) ，男，博士，副教授，主要从事结构耐久性及土木工程材料研究． E-mail:yangyibo@scut.edu.cn
  • About author:杨医博( 1977-) ，男，博士，副教授，主要从事结构耐久性及土木工程材料研究．
  • Supported by:
    Supported by the National Natural Science Foundation of China( 51208210)

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Abstract: Soda residue is a kind of waste produced by the ammonia-soda process for soda ash production.It is very difficult to use soda residue due to the existence of a lot of chlorine ions.In order to solve this problem,the microstructure and chlorine ion dissolution characteristics of soda residue are investigated.The results show that ( 1) soda residue is mainly composed of two components,one is porous calcium carbonate formed through binding and bonding of nano-sized calcium carbonate,and the other is dihydrate gypsum particle; ( 2) there is a well-developed pore structure in soda residue,and the pores include the voids between calcium carbonate congeries particles and dihydrate gypsum particles,the micron-sized pores between the aggregates in calcium carbonate congeries and the nano-sized pores in calcium carbonate aggregates; ( 3) the vast majority of chlorine ions in soda residue exist in the voids between particles and the micron-sized pores within calcium carbonate congeries; and ( 4) adding water to break soda residue and then separating the solid from the liquid is an efficient method to remove chlorine ions from soda residue.

Key words: soda residue, microstructure, chlorine ion dissolution, dechlorination