A combined process for removing hexavalent selenium in water

A combined process and water removal technology, applied in the field of water treatment, can solve the problems of poor selectivity, long time consumption, low removal rate, etc., and achieve the effect of short time, high efficiency and complete removal

Active Publication Date: 2020-08-04
NANJING UNIV
View PDF6 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0010] Aiming at the problems that existing methods for removing hexavalent selenium in water have poor selectivity, low removal rate and long time consumption when other ions coexist at high concentrations, the present invention aims to provide a method for quickly and efficiently removing hexavalent selenium in water

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

Embodiment 1

[0037] This embodiment is a combined process for removing hexavalent selenium in water under the coexistence of high-concentration sulfate. The combined process includes the following steps:

[0038] 1) Using 10 mg / L Se(VI), 1000 mg / L SO 4 2- , the aqueous solution with initial pH=7.0 simulates the aqueous solution containing hexavalent selenium, the total volume of the simulated aqueous solution is 50 mL, 0.5 mL of sodium sulfite solution of 0.5 mol / L is added to the aqueous solution, and the mixed solution is obtained after mixing; The molar ratio of the added sodium sulfite to the hexavalent selenium in the aqueous solution is 39.5:1. In this example, the concentration of sulfite in the water after the addition is theoretically 5 mmol / L. Since the dissolved oxygen will consume a small amount of sulfite, the actual addition of The concentration of sulfite in the backwater was determined to be 4.2 mmol / L by iodometric method.

[0039] 2) After determination, the pH value of...

Embodiment 2

[0046] This embodiment is a combined process for removing hexavalent selenium in water under the coexistence of high-concentration chloride ions. The combined process includes the following steps:

[0047] 1) Using 23.7 mg / L Se(VI), 10 mmol / L Cl - , the aqueous solution with initial pH=8.0 simulates the aqueous solution containing hexavalent selenium, the total volume of the simulated aqueous solution is 50 mL, 0.15 mL of 0.5 mol / L sodium sulfite solution is added to the aqueous solution, and the mixed solution is obtained after mixing; The molar ratio of sodium sulfite to hexavalent selenium in the aqueous solution is 5:1. In this example, the concentration of sulfite in the water after adding theoretically is 1.5 mmol / L. Since dissolved oxygen will consume a small amount of sulfite, after the actual addition The concentration of sulfite in water was determined to be 1.1 mmol / L by iodometric method.

[0048] 2) It is determined that the pH of the solution in step 1) is 9.2, ...

Embodiment 3

[0055] This embodiment is a combined process for removing hexavalent selenium in water under the coexistence of high-concentration sulfate ions. The combined process includes the following steps:

[0056] 1) Contains 10 mg / L Se(VI), 1000 mg / L SO 4 2- , the aqueous solution with initial pH=3.0 simulates the aqueous solution containing hexavalent selenium, and the total volume of the simulated aqueous solution is 50 mL. Add 0.5 mL of 0.5 mol / L sodium sulfite solution to the aqueous solution, and mix to obtain a mixed solution; The molar ratio of sodium sulfite to hexavalent selenium in the aqueous solution is 39.5:1. In this example, the concentration of sulfite in the water after adding theoretically is 5 mmol / L. Because dissolved oxygen will consume a small amount of sulfite, after the actual addition The concentration of sulfite in water was determined to be 4.2 mmol / L by iodometric method.

[0057] 2) It was determined that the pH value of the solution in step 1) was 6.9, ...

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 group technology for removing sexivalence selenium in water, and belongs to the technical field of water treatment. The group technology successively comprises the steps that(1) sodium sulfite is added; (2) the p H is adjusted; (3) ultraviolet radiation is conducted; (4) after tervalence ferric salt and an alkali solution are added and stirred, solid-liquid separation isconducted; (5) air or oxygen is blown in the liquid, or a hydrogen peroxide solution is added, and the liquid is stirred; (6) alkali is added for adjusting p H. Compared with the prior art, the provided group technology has the following advantages that (1) the treating speed is quick, and the effect is good; (2) adding reagent is low in cost and environmentally friendly; (3) the group technologycannot be affected by co-existing ions such as sulfate radical and the like; (4) the control method for adding volume of coagulation reagent is convenient and accurate, and the coagulate effect can be ensured.

Description

technical field [0001] The invention belongs to the technical field of water treatment, and more specifically relates to a combined process for efficiently removing hexavalent selenium in water. Background technique [0002] Selenium is a trace essential element for life activities, but excessive selenium will have negative effects on animal and plant growth and human health. Water is an important source of selenium intake for humans, animals and plants, and the wastewater discharged from human activities, such as coal burning and other fuels, smelting, mining, etc., often contains a large amount of high concentration of selenium, polluting groundwater and surface water. In my country's current comprehensive sewage discharge standards, the first, second, and third-level selenium discharge standards are 0.1, 0.2, and 0.5 mg / L, respectively. 10 μg / L. Therefore, selenium-containing wastewater needs to be strictly treated to meet the standard limit. [0003] In the aquatic env...

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 Patents(China)
IPC IPC(8): C02F9/08C02F101/10
CPCC02F1/00C02F1/32C02F1/5236C02F1/66C02F1/74C02F9/00C02F2101/106
Inventor 潘丙才单超王兴
Owner NANJING UNIV
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