基于DME相变的盾构渣土高效脱水减量化处理研究

Research on high-efficiency dewatering and reduction treatment of shield waste residue based on DME phase transition

近年来城市轨道交通飞速发展,其建设中会产生大量含水率高、性质差的盾构渣土、泥浆等废弃物。这些废弃物难以处置,不仅制约工程施工进度,而且严重影响城市生态安全和居民幸福获得感,因此,亟需对盾构渣土进行减量化、资源化处理。而当前的盾构渣土泥浆压滤脱水工艺效率低下,需进行技术升级或探索新型的脱水工艺。文章基于DME相变现象,探索盾构渣土高效脱水方法,重点研究DME相变对盾构渣土高效脱水的可行性及工艺参数要求。研究结果表明,通过DME相变气化原理,可快速高效脱出渣土中的水分,当DME和渣土的质量比为2时,仅需5~15 min,即可大幅降低渣土或泥饼的含水率,达到近乎干燥状态;气化后的DME可通过增压液化循环使用,该技术具有一定的应用前景。

With the rapid development of urban rail transit in recent years,the wastes of shield waste residue,slurry,etc.,with high moisture content and poor properties will be produced in construction.These wastes are difficult to dispose of,which not only restricts the construction progress of the project,but also seriously affects the urban ecological security and residents'sense of happiness.Therefore,it is urgently needed to carry out reduction and resource treatment of shield waste residue.However,the efficiency of the current filter press dewatering technology of shield waste residue,slurry,etc.,is low,so it is necessary to upgrade the technology or explore a new dehydration technology.In this article,based on the DME phase transition phenomenon,the efficient dewatering method for shield waste residue is explored,and the feasibility of the DME phase transition on the efficient dewatering of shield waste residue and the process parameter requirements is mainly researched.The research results show that through the DME phase transition gasification principle,the moisture in the waste residue can be quickly and efficiently removed,and when the mass ratio of DME to waste residue is 2,the moisture content of waste residue or mud cake can be greatly reduced within 5~15 min,achieving almost the dry state.DME after vaporization can be recycled by pressurized liquefaction,and this technology has certain application prospects.