Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Method for fixing soil heavy metals so as to protect groundwater

A technology for heavy metals and groundwater, applied in the field of fixing heavy metals in soil to protect groundwater, can solve the problems of poor water solubility and diffusivity of lime, improper treatment of leaching liquid, groundwater pollution, etc., and achieve the effects of low cost, low cost and environmental friendliness

Inactive Publication Date: 2015-03-11
SOUTH CHINA AGRI UNIV
View PDF5 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In most cases, in-situ remediation can show its superiority in remediation efficiency and cost, but the problem faced by in-situ chemical leaching is the treatment of the leachate produced by soil leaching. Improper treatment of the leachate will cause groundwater Pollution
At present, the pump-out treatment (P&T) technology is often used in the international leachate, but the cost is high
[0004] The second is the soil heavy metal passivation / immobilization technology. Lime is often used as a passivator for acid-contaminated soil, but the water solubility and diffusibility of lime are poor. If you want to fix heavy metals in deep soil, you must dig out the surface soil and apply it to the deep layer. , thereby increasing the cost

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for fixing soil heavy metals so as to protect groundwater
  • Method for fixing soil heavy metals so as to protect groundwater
  • Method for fixing soil heavy metals so as to protect groundwater

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0025] The method for fixing heavy metals in soil to protect groundwater according to the present invention is specifically: using potassium hydroxide (KOH) fixative to apply on the surface of heavy metal contaminated soil, and through irrigation and natural diffusion to achieve vertical penetration distribution, thereby forming Vertical alkaline fixation belt (medium alkaline fixation belt or high alkaline fixation belt) or formation of alkaline fixation belt (medium alkaline fixation belt or high alkaline fixation belt) in the lower layer of the soil to fix soil heavy metals to protect groundwater The purpose; wherein the amount of the potassium hydroxide fixative is 0.5-2kgm -2 .

[0026] The potassium hydroxide (KOH) selected in the present invention is a water-soluble alkaline substance with good diffusibility and can form a wide range of alkaline bands. The medium alkaline soil can fix heavy metals and reduce the mobility of heavy metals and plants. Effectiveness.

[0027] B...

Embodiment 2

[0031] The difference from Example 1 is that the sugarcane field ridges and furrows are tested to obtain the effect of applying KOH on soil pH at different depths. The specific conditions are as follows:

[0032] The experiment was conducted in a sugarcane field polluted by heavy metals. Choose 5 furrows in the sugarcane field, the ridge height is 45cm, the furrow length is 18m, and the width is 40cm. Sprinkle KOH 1kgm evenly in each furrow. -2 ; Another 3 ditches were selected without any treatment, as a blank control, irrigation water was introduced to make the test field in a flooded state for a period of time, and then the sugarcane was managed according to normal field management. During the test, soil samples are collected once a month, namely, 3 points are randomly selected in the ditch, the surface sampling depth is 0-20cm, and the deep soil samples (20-40cm) are collected with soil drills. The mixed soil samples at multiple points are about 1kg soil. kind. Take it back ...

Embodiment 3

[0035] The difference from Example 1 is the study of the influence of the diffusion of alkaline substances on the formation of alkaline barrier walls on groundwater. The details are as follows:

[0036] The test field is located in a farmland polluted by acid mine wastewater. The annual average temperature is 20.6°C and the annual average rainfall is 1694mm. It has a mid-subtropical monsoon climate. The basic physical and chemical properties of soil and heavy metal content are shown in Table 1 below.

[0037] Table 1 Basic physical and chemical properties of soil

[0038]

[0039] On November 7, 2012, 4 small wells with a diameter of 20cm and a depth of 1.5m were drilled around 2m from the main groundwater sampling well, such as image 3 As shown, 10kg KOH and 5kg lime are added to each small well, and water is added to diffuse the alkaline substances, hoping to form an alkaline barrier wall. The other main sampling well was not processed and served as a control well. On March 21, ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention discloses a method for fixing soil heavy metals so as to protect groundwater; a potassium hydroxide (KOH) fixing agent is adopted for applying on the surface of heavy metal polluted soil, vertical permeability distribution is achieved through water irrigation and natural diffusion, and thus a vertical alkaline fixing band is formed or an alkaline fixing band is formed at the lower layer of the soil to fix the soil heavy metals, so as to achieve the purpose of protecting the groundwater. The potassium hydroxide (KOH) fixing band technology is used for protecting the groundwater, overcomes the problems of slow lime diffusion and small fixing scope, has obvious economic advantages compared with a groundwater pumping-out treatment technology, and is a high-efficiency and low-cost treatment technology in the acidic polluted soil.

Description

Technical field [0001] The invention relates to the technical field of chemical treatment for repairing heavy metal contaminated soil, in particular to a method for fixing soil heavy metals to protect groundwater. Background technique [0002] With the development of industrial and agricultural production, the problem of heavy metal pollution in the soil-plant-water system has become increasingly serious. The National Soil Pollution Survey Bulletin published on April 17, 2014 indicated that the soil point-excess rate of cultivated land in my country was 19.4%. As many as 12 million tons of grains are polluted by heavy metals in our country each year. The economic losses caused by heavy metal pollution of agricultural products are increasing year by year, reaching 32 billion yuan in 2000; and rainwater can pollute groundwater and deteriorate the hydrological environment. And it may directly or indirectly harm humans through contact, food chain and other means. In many key areas,...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): B09C1/08
Inventor 吴启堂卫泽斌陈诚朱朗
Owner SOUTH CHINA AGRI UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com