Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Method for treating mercury-containing wastewater during PVC (Polyvinyle Chloride) production through two-step process

A waste water and step method technology, which is applied in natural water treatment, chemical instruments and methods, water/sewage multi-stage treatment, etc., can solve the problems of high cost mercury removal technology and treatment methods, and achieve saving consumption, less power equipment, and adding less effect

Inactive Publication Date: 2013-02-20
赵建军
View PDF2 Cites 57 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0008] The object of the present invention is to provide a comprehensive, economical, efficient and convenient two-step method for treating PVC production without any mercury loss in view of the high cost of the existing mercury removal technology and the defects or incompleteness of the treatment method. The method of mercury-containing wastewater is suitable for the treatment of mercury-containing wastewater of any concentration,

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 treating mercury-containing wastewater during PVC (Polyvinyle Chloride) production through two-step process

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0021] Before the sample was processed, the mercury content was measured by cold atomic absorption method, which was alkaline wastewater with a mercury content of 3 mg / l and a pH value of 12.5. Then add 0.3% calcium chloride solution of the total amount of wastewater (calcium chloride concentration is 20%), stir for 30 minutes; then use acid to adjust the pH to 7-8, then slowly add PAC and PAM (total addition 30mg / l), after slow stirring for 30 minutes, stop, let stand for 1 hour, and discharge slag; then start aeration, and at the same time start the adsorption tower circulation pump to absorb the gas with sodium sulfide solution to entrain mercury, and stop aeration after 1 hour; use The diatomite filter will filter the treated water and send it to the next step. At this time, the mercury content of the system is measured by cold atomic absorption method and the result is <1mg / l.

[0022]The treated water is filtered by the diatomite filter and stored in the storage tank. A...

Embodiment 2

[0024] Before the sample treatment, the neutral wastewater with a mercury content of 30mg / l and a pH value of 6.5, first added the corresponding molar sodium sulfide solution according to 91% of the molar mercury content, and stirred for 30 minutes; then slowly added PAC and PAM (adding total amount of 30mg / l), stirring at a slow speed for 30 minutes, stop, let stand for 1 hour, and discharge slag; then start aeration, and start the adsorption tower circulation pump at the same time to absorb the gas with sodium sulfide solution to entrain mercury. After 1 hour, stop Aeration; use a diatomaceous earth filter to filter the treated water and send it to the next step. At this time, the mercury content in the system is measured by cold atomic absorption method and the result is <2mg / l.

[0025] The clear liquid filtered by the diatomite filter is stored in the storage tank, and the treated water passes through the activated carbon filter in series, and then through the mercaptan re...

Embodiment 3

[0027] Before the sample treatment, the acid wastewater with a mercury content of 120mg / l and a pH value of 2.5, first added the corresponding molar sodium sulfide solution according to 95% of the molar mercury content, and stirred for 30 minutes; then adjusted the pH value to 6-8, At this time, slowly add PAC and PAM (the total amount added is 30mg / l), stop stirring after 30 minutes at a slow speed, let it stand for 1 hour, and discharge the slag; then start aeration, and at the same time start the adsorption tower circulation pump to absorb gas with sodium sulfide solution After 1 hour, stop the aeration; filter the treated water with a diatomaceous earth filter and send it to the next step. At this time, the mercury content in the system is measured by cold atomic absorption method and the result is <5mg / l.

[0028] The clear liquid filtered by the diatomite filter is stored in the storage tank, and the treated water passes through the activated carbon filter in series, and ...

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 method for treating mercury-containing wastewater during PVC (Polyvinyle Chloride) production through a two-step process. The method comprises the following steps of: firstly, completing primary removal of mercury, copper, ferrous and ferric iron, cadmium, zinc, manganese, lead and suspending impurities of above 10mg / l by using a precipitator and a flocculating agent, regulating PH to 6-8 and then adding the flocculating agent and stirring for 30 minutes, standing for above 1 hour, discharging slag and aerating, absorbing mercury carried away by a gas phase through a sulfide adsorber, purifying water by using a plate type kieselguhr filter, removing residual suspended matters; and 2, carrying out complete reaction on the mercury in the wastewater by using an active carbon and a mercaptan and thiourea resin combining method again for being removed, and finally reaching the standard that the content of the mercury is less than 0.005mg / l. The treated wastewater can be recycled to salt melting or an acetylene generator, so that zero emission of the treated wastewater is achieved; and the mercury-containing waste acid water of hydrochloric acid desorption in the industry of chlor-alkali can be treated, the consumption of acid is reduced, and the great popularization significance is achieved in the industry of chlor-alkali.

Description

technical field [0001] The invention belongs to a wastewater treatment method, in particular to a method for treating mercury-containing wastewater in PVC production through a two-step method with high efficiency and low cost. Background technique [0002] The currently known technical methods for treating mercury-containing wastewater include sulfide direct reaction precipitation method, ion exchange mercury removal method, activated carbon combined adsorption removal method, solution extraction method, and membrane method. [0003] The known and operating sulfide direct precipitation method requires extremely high weighing and adding requirements, so it is easy to cause excess or deficiency of sulfide in actual operation. When the excess is excessive, it will be dissolved again due to the complexation of sulfide ions and mercury sulfide , so it is difficult to achieve the goal of less than 5mg / l in a stable manner; the ion exchange method cannot adapt to the situation when...

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): C02F9/04C02F103/38
Inventor 赵建军
Owner 赵建军
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com