A colloidal slow-release material for in-situ restoration of groundwater and its preparation method

Abstract

The invention discloses a colloid sustained-release material for underground water in-situ remediation and a preparation method of the colloid sustained-release material for underground water in-situ remediation. The colloid sustained-release material is colloidal suspension formed by sufficient mixing of an active remediation agent and colloidal silicon dioxide, wherein a mass ratio of the active remediation agent to the colloidal silicon dioxide is 93-99:1-7, initial viscosity of the colloidal suspension is less than 60cP, and after the colloidal suspension is injected into an underground aquifer, viscosity is increased gradually, semisolid gel is formed finally, and the active remediation agent is released into the aquifer gradually. The colloid sustained-release material for underground water in-situ remediation and the preparation method of the colloid sustained-release material have the advantages that initial injection viscosity of the colloid sustained-release material can be less than 60cP, difficulty in injection into the ground is reduced and accordingly the colloid sustained-release material and the preparation method can be popularized in various types of contaminated sites; after the colloid sustained-release material forms the gel gradually, active remediation agent release time is prolonged by 5-7 times, fluid remediation agent loss and repeated construction defects are avoided, cost saving is achieved and underground water remediation efficiency is improved.

Description

technical field [0001] The invention belongs to the technical field of environmental pollution control and restoration, and relates to a colloidal slow-release material for in-situ restoration of groundwater and a preparation method thereof. Background technique [0002] With the rapid development of my country's national economy and industry, the problem of environmental pollution has become increasingly prominent. Toxic and harmful pollutants enter the underground environmental system through various channels, causing groundwater pollution. In recent years, groundwater pollution around cities and industrial enterprises has become increasingly serious, threatening drinking water safety and human health. Chlorinated olefins are widely used as solvents in metal processing, electronics, dry cleaning and other industries, thus becoming one of the types of pollutants widely distributed in the underground environment [ 1 ] . At the same time, chlorinated olefins were also d...

AI Technical Summary

Problems solved by technology

[0004] The applied in-situ remediation technology still has the following defects in actual site remediation: (1) The commonly used active remediation agents have short half-life, poor stability, and are easily consumed by natural organic matter in the aquifer, thereby reducing the use efficiency of active remediation agents; ( 2) The active remediation agent is mostly injected into the underground aquifer in the form of liquid or gas, which is easy to migrate out of the polluted area under the action of convection, and cannot contact the pollutants in the low-permeability area due to the preferential channel effect. Reduce remediation efficiency; (3) The by-products and permanent impact on the underground environment caused by excessive injection of remediation agents will also limit their use

However, in actual site applications, since the reported slow-release materials are mostly solid, affected by their morphology and particle size, the on-site construction technology is cumbersome, the cost is relatively high, and the scope of applicable sites is limited.

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