System and method for removing organic pollutants in soil employing microwave-assisted soil vapor extraction (SVE)

An organic pollutant, microwave-assisted technology, applied in the restoration of polluted soil and other directions, can solve the problems of high treatment cost and large amount of engineering, and achieve the effect of compact structure, low cost and easy maintenance.

Active Publication Date: 2014-02-05
NORTH CHINA ELECTRIC POWER UNIV (BAODING)
View PDF11 Cites 39 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Ex-situ restoration technology involves excavation and transshipment, and there is a risk of secondary pollutio

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
  • System and method for removing organic pollutants in soil employing microwave-assisted soil vapor extraction (SVE)

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0029] A chemical factory in Beijing stopped production and relocated, and then left about 1.5 million m3 idle 2 soil of. A 20m×20m site is selected for soil remediation. According to field investigation, the strata within 20m below the surface in this area are divided into two categories: artificial accumulation layer and Quaternary sedimentary layer. A layer of groundwater is mainly distributed in the depth range of about 20m below the surface, which occurs in the sandy soil layer with a buried depth of 12.40-13.55m, and the type of groundwater is phreatic. After on-site investigation and sampling analysis, it is known that the pollutants in soil and groundwater include a large number of volatile organic compounds (VOCs) (mainly benzene series), semi-volatile organic compounds (SVOCs), polycyclic aromatic hydrocarbons (PAHs) and non-aqueous phase liquids (NAPLs). The gas extraction wells are more than 4m deep, and a total of 6 gas extraction wells, 8 air injection wells a...

Embodiment 2

[0031] In a polluted factory area, the main organic pollutants in the soil were determined to be toluene, ethylbenzene and n-propylbenzene. The soil type is yellow brown soil, and the groundwater type is aquiferous layer. Select the polluted area of ​​15m×25m, set up 5 air extraction wells, 4 monitoring wells and 7 air injection wells, and use activated carbon and iron filings as wave-absorbing materials. The air extraction flow rate is maintained at 0.15L / s, and the soil moisture content is maintained at about 17.89%. The microwave heater basically runs once every 10 minutes, each time lasts 20 minutes, the microwave power is 30Kw, and the frequency is 915MHz. The temperature setting range is from 100°C to 300°C. After 8 hours of treatment, the removal rates of toluene, ethylbenzene, and n-propylbenzene were 99.84%, 99.45%, and 98.25%, respectively.

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 belongs to the technical field of in-situ remediation of soil pollution, and particularly relates to a system and a method for removing organic pollutants in soil employing microwave-assisted soil vapor extraction (SVE). The method comprises the following steps: injecting a microwave-assisted material into soil to be repaired; paving an airtight cover membrane on the surface of the area of the soil to be repaired; providing one or more pumping wells in the area of the soil to be repaired; providing a plurality of air injection wells, monitoring wells and injection pipelines within a theoretical coverage range of the pumping wells. By adopting the method, a microwave is adopted as a heat source, so that various of organic pollutants in the soil are primarily processed by volatilization and decomposition mechanisms; desorption of adsorbed state organic matters in soil particles is facilitated; steam state formation of volatile organic compounds (VOCs) is accelerated; the extracted steam is processed by a ground waste gas and wastewater treatment device, so as to achieve the target of repairing the organic polluted soil. The technology has the advantages of being low in cost, strong in maneuverability, wide in range of processing organic matters, free of damage to a soil structure, free of secondary pollution and the like, can adopt standard equipment, and has a broad application prospect.

Description

technical field [0001] The invention belongs to the technical field of in-situ remediation of soil pollution, and in particular relates to an in-situ remediation technology of soil polluted by volatile organic pollutants, in particular to a microwave-assisted soil vapor extraction (SVE) technique for removing organic pollutants in soil systems and methods. Background technique [0002] With the rapid development of industry and agriculture in our country, the pollution of soil and groundwater is becoming more and more serious. Soil and groundwater are not only important agricultural production resources, but also important environmental elements and the basis for human survival. It not only restricts agricultural production and industrial development more and more, but also affects people's health. Among them, organic pollution is characterized by its persistence, high toxicity, accumulation, and fluidity. It will accumulate for a long time and is difficult to remove throu...

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): B09C1/06
Inventor 何理潘海洋卢宏玮张一梅
Owner NORTH CHINA ELECTRIC POWER UNIV (BAODING)
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products