为了保证工作面的安全，并有效运输隧道掘进时挖出的土碴，采用膨润土支护液体，完成任务后的支护液体必须经过处理，分离出来的沙土可以在工地上得到再利用（作为隔音墙和填充料）。从土碴处理和再利用的角度对泥水分离设备进行优化，从而使资源得到了保护，由于膨润土和絮凝剂的消耗最小化，提高了隧道工程的经济性，并减小了对环境的污染。

Bentonite suspension is used to protect the working face and to transport the excavated material during tunnel construction. The bentonite suspension needs to be cleaned after it has fulfilled its task. The separated sandy material is reused at the construction site (noise barriers, sand fillings). By optimizing the separation plant for the treatment of the soil material and for the recycling, resources are saved. By minimizing the consumption of bentonite and flocculances, the cost effectiveness of the project is increased and the environment is less polluted.