Unlock instant, AI-driven research and patent intelligence for your innovation.

Preoxidized-composite electrolyzing method for removing arsenic in groundwater

A groundwater, pre-oxidation technology, applied in the field of water treatment, can solve problems such as slow corrosion rate

Inactive Publication Date: 2008-03-12
HARBIN INST OF TECH
View PDF0 Cites 33 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to provide a method for removing arsenic in groundwater by pre-oxidation-compound electrolysis, so as to overcome the defects that pure zero-valent iron is relatively expensive and the corrosion rate is relatively slow, which limits the adsorption of arsenic on zero-valent iron

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

Examples

Experimental program
Comparison scheme
Effect test

specific Embodiment approach 1

[0007] Specific embodiment one: present embodiment is made up of following steps: one, utilize ozone, potassium ferrate, potassium permanganate or H 2 o 2 Pre-oxidize the arsenic-containing groundwater to convert As(III) into As(V); 2. The pre-oxidized water passes through the filter bed containing cast iron chips and carbon particles, and the remaining oxidant in the pre-oxidation stage promotes the reaction of this step .

[0008] Sand and gravel are used as auxiliary filler layers above and below the iron-carbon layer. The contact time between water and oxidant is controlled within 5-15 minutes, and the hydraulic retention time of water in the iron-carbon filter bed can be controlled within 5-60 minutes according to the difference of arsenic concentration in the water. Cast iron shavings and charcoal particles should be cleaned before use to remove surface contamination. The mixing ratio of cast iron shavings and carbon particles is 20-50:1 (by weight) or 1:1-2:1 by volu...

specific Embodiment approach 2

[0010] Embodiment 2: The difference between this embodiment and Embodiment 1 is that the groundwater should be aerated before entering the iron-carbon filter bed to increase the concentration of oxygen in the water to promote the corrosion of iron and the adsorption of arsenic.

specific Embodiment approach 3

[0011] Embodiment 3: The difference between this embodiment and Embodiment 1 is that the pH of the groundwater is adjusted in the range of 3-6 before entering the iron-carbon filter bed, so as to promote the corrosion of iron and the adsorption of arsenic.

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 sizeaaaaaaaaaa
Login to View More

Abstract

A method to remove arsenic in underwater by preoxidation-combined electrolyzing relates to a method to remove arsenic from underwater, belonging to the technical field of water treatment. The present invention has solved the defect that more expensive pure nulvalent iron and slower corrosion speed of the pure nulvalent iron have limited the absorption of arsenic on the nulvalent iron. The present invention includes the following steps: the underwater containing arsenic is pre-oxidized by ozone, potassium ferrate, potassium permanganate, H2O2, photocatalysis oxidation reagent or Fenton reagent, thereby transferring As(III) to As(V). The water pre-oxidized passes through a filtering bed containing cast-iron scrap and carbon granules. The oxidizer left in the preoxidation section promotes the reaction of the step.

Description

technical field [0001] The invention relates to a method for removing arsenic in groundwater, belonging to the technical field of water treatment. Background technique [0002] Groundwater is the main source of water for cities and industry and agriculture in my country. Some cities in Xinjiang, Inner Mongolia, Shaanxi, Guizhou, Jilin, Ningxia, Qinghai and other provinces in China have the problem of excessive arsenic in drinking water to varying degrees. An inexpensive method to remove arsenic from groundwater is an urgent problem to be solved. [0003] At present, the commonly used processes for removing arsenic in water can be divided into ion exchange method, reverse osmosis method, coagulation precipitation method and adsorption method. Ion exchange is usually not efficient for arsenic removal because the concentrations of other ions that compete with arsenic are usually much higher than the arsenic concentration. Reverse osmosis can reduce arsenic levels down to 10 μg...

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): C02F9/06C02F1/58C02F1/461C02F1/72
Inventor 马军关小红姜利刘德钊
Owner HARBIN INST OF TECH