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

Device and technology for treating acidic wastewater by producing expansible graphite through sodium dichromate process

A technology of expanded graphite and sodium dichromate, which is applied in water/sewage treatment, water treatment parameter control, neutralized water/sewage treatment, etc. It can solve problems such as difficulty in meeting discharge requirements, failure to meet standards stably, and low treatment efficiency. , to achieve the effect of stable treatment effect, high degree of equipment automation and low operating cost

Inactive Publication Date: 2019-03-29
上海班德环保科技股份有限公司
View PDF6 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The chemical precipitation method is used to treat expandable graphite acidic wastewater by adding alkali to neutralize the dilute acid in the wastewater, using alkali to adjust the pH of the wastewater to a certain range, using alkali to react with heavy metal ions, and using sedimentation tanks to separate heavy metal hydroxides for precipitation , but chromium in wastewater exists in two forms of hexavalent chromium and trivalent chromium. Trivalent chromium is easy to form corresponding hydroxide precipitates and has low toxicity. Hexavalent chromium is relatively difficult to form corresponding hydroxide precipitates and is toxic. Therefore, the use of alkali alone to neutralize and precipitate heavy metal ions in wastewater has the disadvantage of low treatment efficiency, and it is difficult to meet the discharge requirements; the electrocoagulation oxidation precipitation method only needs to add part of lye to treat expandable graphite acidic wastewater Adjust the wastewater to a certain pH without adding reducing agents, flocculants and other agents to treat the wastewater, but there are defects such as easy corrosion of the plates, large power consumption, low processing load, and high processing costs, which limit its use to a certain extent
As mentioned above, for the treatment of expandable graphite acid wastewater produced by the sodium dichromate method, there is currently no mature treatment process that can meet the standards stably, with high treatment load and low treatment cost.

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
  • Device and technology for treating acidic wastewater by producing expansible graphite through sodium dichromate process
  • Device and technology for treating acidic wastewater by producing expansible graphite through sodium dichromate process

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0024] Embodiment 1: see figure 1 , a sodium dichromate method produces expandable graphite acidic wastewater treatment equipment, including a graphite recovery unit (a graphite recovery pool in the embodiment) for reclaiming expandable graphite particles, a regulating unit for balancing water quality and quantity (the embodiment In the middle is the adjustment pool), for reducing the hexavalent chromium in the waste water to the reduction reaction unit of the trivalent chromium (in the embodiment, it is the reduction reaction pool), in the neutralization reaction unit (in the embodiment, it is the neutralization reaction pool), with A filter press unit (a filter press in the embodiment), a filtrate storage unit (a filtrate pool in the embodiment) for dehydrating and drying the generated sludge, and a filter unit for removing suspended solids of heavy metal particles formed in wastewater (In the embodiment, it is a filter, and the equipment is self-produced by our company. For...

Embodiment 2

[0040] Embodiment 2: the technology in this embodiment relates to the equipment in embodiment 1, see figure 2, a sodium dichromate method to produce expandable graphite acidic wastewater treatment process, the acidic wastewater produced in the workshop first enters the graphite recovery pool (graphite recovery unit) to recover the fine particles of expandable graphite remaining in the wastewater, and then lifts it to the Reduction reaction pool (reduction reaction unit); add ferrous sulfate to adjust the ORP potential of wastewater, and control the ORP potential between 482-485mV. When the ORP online monitor detects that the wastewater potential is lower than 482mV, the control system sends out the addition of ferrous sulfate Solution instruction (realized by the automatic dosing machine of the reduction reaction unit), when the ORP online monitor detects that the wastewater potential is higher than 485mV, the control system issues an instruction to stop adding ferrous sulfate...

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 device for treating acidic wastewater by producing expansible graphite through a sodium dichromate process. The device comprises a graphite recycling unit, a regulating unit,a reduction reaction unit, a neutral reaction unit, a filter pressing unit, a liquid storage unit and a filtering unit, wherein the graphite recycling unit is used for recycling expansible graphite particles; the regulating unit is used for balancing water quality; the reduction reaction unit is used for reducing hexavalent chromium in wastewater into trivalent chromium; the filter pressing unitis used for dewatering and drying the generated sludge; the filtering unit is used for removing heavy metal particles and suspended solids formed in wastewater; all the units are connected with each other in turn. The invention also discloses a technology for treating acidic wastewater by producing expansible graphite through the sodium dichromate process. According to the invention, wastewater treatment is stable and reaches standard, treatment load is high and treatment cost is low.

Description

technical field [0001] The invention relates to the field of wastewater treatment, in particular to a treatment process and equipment for acidic wastewater produced from expandable graphite by a sodium dichromate method. Background technique [0002] Sodium dichromate method to produce expandable graphite acidic wastewater Existing wastewater treatment technologies mainly include chemical precipitation and electrocoagulation oxidation precipitation. The chemical precipitation method is used to treat expandable graphite acidic wastewater by adding alkali to neutralize the dilute acid in the wastewater, using alkali to adjust the pH of the wastewater to a certain range, using alkali to react with heavy metal ions, and using sedimentation tanks to separate heavy metal hydroxides for precipitation , but chromium in wastewater exists in two forms of hexavalent chromium and trivalent chromium. Trivalent chromium is easy to form corresponding hydroxide precipitates and has low toxi...

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): C02F9/04C02F101/22C02F11/122
CPCC02F1/001C02F1/5236C02F1/56C02F1/66C02F1/705C02F9/00C02F11/122C02F2101/22C02F2209/04C02F2209/06
Inventor 于大成于明军
Owner 上海班德环保科技股份有限公司