航道疏浚淤泥管中固化处理试验研究

Experimental study on in-pipe solidification of sediment dredged from waterway

基于管中气动输送固化土技术,研制了一套柱塞式管中混合固化试验系统,开展固化剂配制、管道方案设计和试验研究。以水泥、粉煤灰和生石灰作为三掺固化剂配料,水泥用量在3%～5%,可降低成本,提高固化效果。柱塞式管中固化系统以疏浚泥含水率调整装置、压缩空气输入和固化剂注入装置为主要组成部分。在固化剂注入处将输泥管直径扩大1倍作为混合区,根据CFD数值仿真确定混合区的长径比为5.8∶1。通过调整三部分的输入压力,可获得较好的混合效果,有效通过输泥管道输送固化土。该试验系统适合于大体积量固化土制备、输送和高效的处理,可为我国疏浚淤泥的处理提供参考。

Based on the technology of in-pipe pneumatic transportation of solidified sediment,a set of plunger type in-pipe flow mixing soil-solidification experimental system is developed,and then the mixing of solidifying-agent,the design of pipeline scheme and the relevant experimental study are carried out. By taking cement,flyash and lime as the admixtures for mixing the solidifying-agent,if the cemnt content is about 3% ～ 5%,not only the cost can be reduced,but the solidifying effect can also be enhanced. The main components of the plunger type i in-pipe flow mixing soil-solidification experimental system are the device for adjusting the water content of dredged sediment,the compressed air feeding and solidifying-agent filling devices. The diameter of the discharge pipe is enlarged by one time at the position that the solidifying agent is filled in as the mixing zone,for which the length-diameter ratio of 5. 8 ∶ 1 is determined with CFD numerical simulation. Through adjusting the input pressures of the three parts（ i. e. dredged sediment,compressed air and solidifying-agent） better mixing effect can be obtained,and then the solidified soil can be effectively transported through the discharge pipeline. This experimental system is suitable for the preparation,transportation and high-efficient disposal of large-volume solidified soil,which can provide a reference for the disposal of dredged sediment in China.