Method for purifying cadmium-containing paddy soil

A cadmium paddy field and soil technology, applied in the restoration of polluted soil, separation method, improvement of process efficiency, etc., can solve problems such as inability to install drainage treatment devices, high cost, and high cost

Active Publication Date: 2013-03-20
TAIHEIYO CEMENT CORP
View PDF9 Cites 13 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

When installing such a device, there is a problem that it costs a lot and the cost becomes high.
In addition, depending on the location of the soil to be purified, it may not be possible to install equipment such as drainage treatment equipment.

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 purifying cadmium-containing paddy soil
  • Method for purifying cadmium-containing paddy soil
  • Method for purifying cadmium-containing paddy soil

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0053] Weigh 2000g of cadmium-containing air-dried paddy field soil, put it into a 5000mL tank, add 4000mL of 20mM ferric chloride solution, stir it with a three-one motor (Three-One Motor) for 1 hour, let it stand still, and recover the supernatant. Think of it as a "soil wash drain". The pH of "soil cleaning and drainage" is 3.3, and the concentration of cadmium: 1.55mg / L.

[0054] Weigh 50g of cadmium-containing air-dried paddy field soil in a 200mL beaker, add 100mL of "soil washing and drainage", and add aqueous sodium hydroxide solution in multiple stages. Further, after stirring for 10 minutes with a magnetic stirrer, the soil was allowed to stand still, the soil was allowed to settle, the supernatant water was collected, and the pH and cadmium concentration were measured. In addition, the case where only cadmium-containing air-dried paddy field soil and soil washing drainage were treated in the same manner without using an aqueous sodium hydroxide solution is shown as...

Embodiment 2

[0058] Weigh 50g of air-dried paddy field soil in multiple 200mL beakers, and add 100mL of "soil washing and drainage" prepared in Example 1 respectively. 50 to 250 mg of various basic materials were added to each beaker. Shake and stir for 10 minutes, let the soil settle, and measure the pH and cadmium concentration of the supernatant water. The results are shown in Table 2.

[0059] Table 2:

[0060]

Embodiment 3

[0062] Weigh 50 g of air-dried paddy field soil into multiple 200 mL beakers, add 2.5 g (5% by mass relative to the air-dried paddy field soil) of bentonite, and stir and mix with a glass rod. Add 100 mL of "soil washing and drainage" prepared in Example 1 respectively, and add an appropriate amount of sodium hydroxide aqueous solution, shake and stir for 10 minutes, and adjust to pH7 or pH8. Thereafter, the soil was allowed to stand still, and the cadmium concentration in the supernatant water was measured. The results are shown in Table 3.

[0063] table 3:

[0064]

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

A method for purifying cadmium-containing paddy soil characterized by gathering a detergent drain containing cadmium at one place in a paddy to be washed, subjecting the drain to neutralization or alkali treatment at the place, and accumulating cadmium, in a in-place purification method including washing cadmium-containing paddy soil by a drug solution to extract cadmium, separating the resultant into soil and supernatant by standing, draining the extracted cadmium as supernatant, and further performing a diluent washing with water. The cadmium-containing paddy soil can be efficiently purified.

Description

technical field [0001] The invention relates to a method for efficiently purifying paddy field soil containing cadmium. Background technique [0002] CODEX (International Committee on Food Standards established by WHO and FAO) discusses the reference value of Cd concentration in crops, and in July 2006, for rice, a scheme of 0.4 mg / kg was adopted (Non-Patent Document 1). Japan accepted this proposal, and on April 8, 2010, the Cd component standard of rice based on the Food Sanitation Law was revised from less than 1.0 mg / kg to less than 0.4 mg / kg. Furthermore, on June 11, 2010, the requirements for designation of Cd in agricultural land soil pollution countermeasure areas based on the Agricultural Land Soil Pollution Prevention Act were revised from 1 mg or more per 1 kg of brown rice or areas where the risk is significant to 0.4 mg or more areas or areas of significant danger. [0003] In the future, a considerable area in Japan may be designated as Cd-contaminated agricu...

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): B09C1/02B09C1/00B09C1/08C02F1/28C02F1/40
CPCB09C1/02C22B17/04Y02P10/20
Inventor 神谷隆高野博幸竹本智典青野克己牧野知之前岛勇治赤羽几子
Owner TAIHEIYO CEMENT CORP
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

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap