Study On The Engineering Characteristics Of 'the Third Storage Yard' Soda Residue And The Transport Schemes

The traditional soda production produces 9~l0m3 soda residue per 1 ton pure soda. The soda residue uses up a lot of grounds and becomes a great obstacle to the soda production development. The discharge field of soda residue produced by Tianjin soda factory is called'the third storage yard', which is located in the southwest of Tianjin Port North Container Center. The area of the storage yard is 0.7km2 and the height of it is more than 15m. The quantity of the soda residue is so great that it plays a negative role in Tianjin Port construction. As a result, how to move the soda residue hill with extremely high water content, low strength and thixotropy safely and utilize it rationally becomes an important issue of Tianjin Port construction.This thesis studies on the formation and chemical composition of soda residue. The thermograph analysis, energy spectrum analysis, x-ray diffraction analysis and electron microscopic scanning have been applied to study the microstructure of the interaction between the grains of soda residue and water, further understands the characteristics of the original crystalline particles, figures out the mechanism of the interaction of the soda residue and water, and reveals the strength mechanism of soda residue. Through the indoor physical and mechanical tests, the physical and mechanical properties of soda residue can be understood on a macro scale. It shows that the original soda residue of'the third storage yard'has extremely high water content, large porosity ratio, high compressibility and low strength.Base on the research of the physical and chemical properties, the strength mechanism and engineering mechanical properties of the soda residue, this thesis concentrates on the way of moving the soda residue hill safely and proposes three schemes. The first one is using sulfuric acid to improve the strength of the soda residue, thus provide the possibility of transporting the soda residue; the second one is making use of well-point dewatering to move the soda hill by excavating in layers and blocks; the third one is by pumping.The feasibility of the proposed schemes has been analyzed in great detail. The first one is unfeasible for the sulfuric acid can not improve the strength of soda residue effective. For the second scheme, analyzing the stability of the whole soda residue hill by finite element method and limiting balanced method shows the soda residue hill of 17 heights is in a stable state, further imitates the stability of the process of the excavating by layers and blocks after well-point dewatering. The analyzing results show that this scheme can ensure the stability of the process of transport the soda residue hill. In addition, a preliminary design of the third scheme'pumping'is proposed.