以电石渣的氯化铵浸取液——氯化钙-氨水体系为研究对象，以中试装置为研究平台，分别探讨了单纯二氧化碳碳化过程和碳酸氢铵+二氧化碳复合碳化过程的反应机理。单纯二氧化碳碳化过程时间长、速度慢、粒子粗、团聚严重，其根源是氯化钙-氨水体系pH低，吸收二氧化碳反应速度慢，碳化初期不可能形成大量碳酸钙晶核，不利于粒子超细化。复合碳化过程则相反，其根源在于碳酸氢铵的复化学碳化能够在短时间内形成大量碳酸钙晶核，有利于粒子超细化。无论是单纯二氧化碳碳化过程还是碳酸氢铵+二氧化碳复合碳化过程，氨都属于关键少数，体系难以达到氨的平衡，游离氨的离解反应都是慢速反应和控制步骤。

The reaction mechanisms of carbon dioxide carbonation and ammonium bicarbonate+carbon dioxide composite carbonation were discussed in the pilot plant with the ammonia chloride leaching solution of calcium carbide slag that was calcium chloride?鄄ammonia water system as the research object.The carbon dioxide carbonization process was long and slow，and the particles were coarse and agglomeration was serious.The root cause was that pH of the calcium chloride?鄄ammonia system was low，and the reaction rate of carbon dioxide absorption was slow.It was um carbonate nucleus at the initial stage of carbonization，which was not conducive to ultrafine particles. On the contrary，the complex carbonization process was rooted in the fact that the complex carbonization of ammonium bicarbonate could form a large number of calcium carbonate nucleus in a short time，which was conducive to the ultrafine particles.Ammonia was a key minority in either carbon dioxide carbonation process or ammonium bicarbonate+carbon dioxide composite carbonation process.It was difficult for the system to achieve ammonia equilibrium.The dissociation of free ammonia was a slow reaction and control step.impossible to form a large amount of calci?鄄