Design And Research Of Filter Pipe For Multi-filter Circulating Well

Groundwater circulating well as an in situ remediation technology has attracted extensive attention in recent years.The well structure of circulating well is mainly composed of filter pipe,well pipe and settling pipe.As an important part of circulating well,the filter pipe is very important to the three-dimensional circulation of groundwater.By means of theoretical analysis,numerical simulation,construction of circulating well demonstration well and trial operation of circulating well,this thesis analyzes and studies the filter pipe of circulating well,analyzes the stress and deformation of circulating well filter pipe in the well,clarifies the failure form of circulating well filter pipe,and provides a theoretical basis for the selection of circulating well filter pipe.Firstly,the development history and operation principle of circulating well are analyzed.Circulating well technology originated in foreign countries and has been well developed.It operates on the basis that groundwater enters a circulating well from one filter pipe,is treated and injected into the formation from another filter pipe.Secondly,the stress of the filter pipe is analyzed.In the process of downhole pipe formation in circulating well,the filter pipe will be subjected to the tension of the downhole pipe.After a circulating well is completed,the filter pipe will be subjected to pressure from the upper well pipe and the formation.The tension and pressure on the filter pipe can be calculated from the density,thickness,diameter and length of the well pipe,and the confining pressure can be calculated from the static earth pressure formula of the formation.The force of the filter pipe is compared with its strength to verify its effectiveness.Then,the failure form of the filter pipe is analyzed.It includes axial tensile deformation failure,confining pressure deformation failure and plugging failure,among which the most common ones are confining pressure deformation failure and plugging failure.In this thesis,the deformation failure and plugging failure of filter pipe confining pressure are analyzed theoretically,and the corresponding measures are given.Through the software of the filter pipe numerical modeling,finite element analysis of the model,the stress and strain of the filter pipe after the stress,to provide a basis for the selection of the filter pipe.Finally,construction and trial operation of circulating well test well V1.0.This thesis describes the main well structure and design concept of IEG company,introduces the installation process and matters needing attention of the main well and auxiliary well of circulating well,and designs a kind of circulating well body structure according to the characteristics of circulating well.After trial operation for a period of time,the water yield is within the design range,which proves that the selected filter pipe can meet the design requirements.