Treatment method of soil contaminated by uranium or cesium

A technology of polluted soil and treatment methods, applied in the field of microorganisms, can solve problems such as limited physical decontamination efficiency, secondary pollution, and no practical value, and achieve the effect of simple operation, efficient removal, and low cost

Inactive Publication Date: 2010-06-23
CHENGDU INST OF BIOLOGY CHINESE ACAD OF S
View PDF0 Cites 22 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0012]In summary, the treatment process of radionuclides in uranium or cesium slightly polluted soil at home and abroad is not yet mature, and the existing research has the following problems: First, the physical The decontamination efficiency is limited, the second is that the chemical washing method is easy to cause secondary pollution, and the third is that the existing microbial remediation technology is still in the preliminary research stage and has no practical value at present

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
  • Treatment method of soil contaminated by uranium or cesium
  • Treatment method of soil contaminated by uranium or cesium
  • Treatment method of soil contaminated by uranium or cesium

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0022] 1) Activated acidophilus Thiobacillus ferrooxidans (A.f bacteria): The activation medium formula is 0.40g KCl, 0.50g MgSO 4 ·7H 2 O, 0.10g Ca(NO 3 ) 2 ·4H 2 O, 0.01g CuSO 4 ·5H 2 O, 0.10g KH 2 PO 4 , 0.40g(NH 4 ) 2 Fe(SO 4 ) 2 ·6H 2 O, 990mL tap water. Adjust the pH value of the culture solution to 2.0-2.3, sterilize for 30 minutes under a steam pressure of 0.1 MPa, and cool. Then 10 mL of 30% FeSO4 was separately filtered and sterilized and added to the sterilized solution. Take 150 mL of the activation medium into a 500 mL Erlenmeyer flask, and add 20 mL of the active bacterial solution of A.f bacteria to the activation medium, and then place it in a constant temperature shaker at 28-32°C for 14 days. According to the same method, gradually reduce the inoculum amount for transfer culture, after repeated transfer culture and filtration, the active bacteria liquid of A.f bacteria (microbial biomass 10-15g / L) is obtained.

[0023] 2) Activated sulfate reducing bacteria (SR...

Embodiment 2

[0035] 1) Activated acidophilus Thiobacillus ferrooxidans (A.f bacteria): same as Example 1.

[0036] 2) Activated sulfate-reducing bacteria (SRB bacteria): the same as in Example 1.

[0037] 3) Preparation of reaction medium rich in iron and sulfur: (NH 4 ) 2 SO 4 2.50g, KH 2 PO 4 2.50g, MgSO 4 ·7H 2 O 0.50g, CaCl 2 ·2H 2 O 0.25g, FeSO 4 ·7H 2 O 6.85g, sulfur powder 3.40g, pyrite powder 1.90g, add tap water to 1000mL and mix well.

[0038] 4) Preparation of solubilizer: Na 2 S 2 O 3 ·5H 2 O 21.85g, DTPA 21.25g, formic acid 12.55mL, citric acid 10.90g, ammonium phosphate 0.46g, EDTA-Na 2 13.55g, 24.35g organic fertilizer, add tap water to 1000mL and mix well.

[0039] 5) Screening volume reduction of uranium-235 micro-polluted soil: same as Example 1.

[0040] 6) In the microbial solubilization reactor (4), the Af bacteria active bacteria liquid and the solubilizing aid are mixed at a ratio of 1.0:1.8 (v / v), and then 108.70g soil / 100mL Af bacteria and solubilizing aid are mixed. Add th...

Embodiment 3

[0047] 1) Activated acidophilus Thiobacillus ferrooxidans (A.f bacteria): same as Example 1.

[0048] 2) Activated sulfate-reducing bacteria (SRB bacteria): the same as in Example 1.

[0049] 3) Preparation of reaction medium rich in iron and sulfur: (NH 4 ) 2 SO 4 2.50g, KH 2 PO 4 2.50g, MgSO 4 ·7H 2 O 0.50g, CaCl 2 ·2H 2 O 0.25g, FeSO 4 ·7H 2 O 4.00g, sulfur powder 2.10g, pyrite powder 3.50g, add tap water to 1000mL and mix well.

[0050] 4) Take the cesium-137 micro-polluted soil through an iron grid screen, a double-plate screen, and a spiral screen in turn. After sieving out larger-diameter soil particles, the soil particles with a particle diameter less than 0.25mm are contaminated soil to be treated after volume reduction.

[0051] 5) In the microbial solubilization reactor (4), cesium-137 micro-polluted soil is poured into the soil at the amount of 144.93g soil / 100mLA.f active bacteria liquid, and then the amount of 17.0mL / 100g soil will be rich in iron The reaction medium wit...

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

PropertyMeasurementUnit
particle diameteraaaaaaaaaa
particle diameteraaaaaaaaaa
Login to view more

Abstract

The invention belongs to the technical field of the microorganism, and in particular to a treatment method of soil contaminated by radioactive nuclide uranium or cesium. The invention adopts a bar screen, a double-plate screen and a spiral screen to screen the soil contaminated by uranium or cesium. The soil particles with the particle size more than 0.25mm are clean soil particles, the soil particles with the particle size less than 0.25mm are soil contaminated by uranium or cesium; and the soil particles with the particle size less than 0.25mm are mixed with active acidithiobacillus ferrooxidans for treatment, and the settlement is clean soil after filtration, the filtrate is transferred and mixed with active sulfate reducing bacteria for treatment, then the uranium or cesium is precipitated and can be recovered through filtering separation, and the water can also be recovered. The invention has the advantages of simple operation and low cost, and realizes the rapid and efficient removal of the uranium or cesium in the slightly contaminated soil.

Description

Technical field [0001] The invention belongs to the technical field of microorganisms, and specifically relates to a method for treating soil contaminated by radionuclides uranium or cesium. Background technique [0002] Activities such as mining operations, national defense scientific research activities, the disposal of radioactive waste, and the gradual opening of nuclear weapons test bases have led to increasingly serious environmental radioactive pollution problems. Among them, the treatment and restoration of contaminated soil containing radionuclides has received increasing attention. [0003] Uranium mining, nuclear weapons tests, and the widespread use of nuclear energy have led to continuous enrichment and pollution of uranium in the environment. Uranium tailings and waste rocks contain uranium and all its progeny, and its radionuclide content is 2 to 3 orders of magnitude higher than the background. Improper accumulation or disposal of these waste materials will cause ...

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
Patent Type & Authority Applications(China)
IPC IPC(8): B09C1/10C12N1/20
Inventor 袁世斌董微李娜
Owner CHENGDU INST OF BIOLOGY CHINESE ACAD OF S
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