碱渣是氨碱法制纯碱排出的废渣，由于其中含有大量的氯离子，利用非常困难．为解决这一问题，文中开展了碱渣的微观结构及氯离子溶出特性的研究． 结果表明: 碱渣
主要由纳米级碳酸钙通过结合和搭接形成的多孔碳酸钙、二水石膏颗粒构成，存在发达的孔隙结构，包括碳酸钙聚集体颗粒和二水石膏颗粒之间的空隙、聚集体内部的团聚体颗粒之间的微米级孔隙、团聚体颗粒内部的纳米级孔隙; 碱渣中的氯离子绝大部分存在于颗粒间的空隙及碳酸钙颗粒内的微米级孔隙中; 建议采取加水充分打散碱渣、再使固液分离的方法去除氯离子．

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.