基于硅酸盐对建筑垃圾过滤分离的脱水机理研究

Mechanical Research on Dehydration in the Filtration and Separation of Construction Waste Based on Silicate

硅酸盐是典型的建筑垃圾,硅酸盐的脱水性能直接影响了建筑垃圾的处理效率。为探究硅酸盐结晶状态对脱水效果的影响,在不同的合成温度、合成时间条件下得到不同结晶状态的硅酸盐,并从宏观水平、介尺度水平和分子水平对所得的硅酸盐晶体的脱水效果加以分析。研究表明,在合成温度为200℃时硅酸盐结晶过程较复杂,是非晶态到晶态的过渡区,对应的硅酸盐晶体脱水效果最好。同时,在合成温度200℃、合成时间4 h得到的硅酸盐晶体过滤速度最快,过滤后滤饼含水率最低,而合成8 h得到的硅酸盐晶体过滤效果较差,其原因是受微观形貌、层间水释放、比表面积和水分赋存状态的影响。

Silicate is a typical construction waste.The dehydration performance of silicate directly affects the efficient disposal of construction waste.To research the effect of dehydration caused by silicate crystalline state,different silicate crystalline states were prepared under different crystallization temperature and different crystallization time.The effect of dehydration was studied under macro level,molecular migration and molecular level.The results show that the most complicated crystallization stage is the transient process which contains noncrystalline state and crystal state,and the crystallization temperature is 200℃.The product obtains at this state dehydrated best.At the same time,the silicate crystalline product obtained at 4 h under 200℃ reaches the highest filtering speed,and moisture content of the filter cake at the least value.However,the silicate product obtains at 8 h dehydrated worst.The reasons of this phenomenon are caused of the morphology of crystalline,the release of interlayer water,specific surface area and the state of moisture occurrence.