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

Method for recycling iron-rich sludge from pulp and paper mill wastewater

A technology for pulping, papermaking and papermaking, which is applied in the field of solid waste recycling, can solve the problems of poor dehydration effect, high reuse value, unstable structure, etc. Effect

Active Publication Date: 2017-04-26
CHINA CEC ENG +1
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] This treatment method for iron-rich sludge has the following problems: First, the actual operation of sludge dewatering in paper mills shows that the iron-rich sludge has small particles and unstable structure, and it directly interacts with primary sludge and residual sludge. The dehydration effect becomes worse after the mud is mixed; secondly, in the dehydration process of the mixed sludge, a large amount of inorganic conditioner and polymer flocculant are added, which increases the cost of sludge treatment, and the additional sludge dewatering agent itself The weight of the sludge is transferred to the dewatered sludge, thereby increasing the amount of sludge dewatered and increasing the load of sludge dewatering; third, the iron-rich sludge itself contains a large amount of iron and has high reuse value. Simple dehydration and incineration disposal do not conform to the concept of waste resource recycling

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 recycling iron-rich sludge from pulp and paper mill wastewater

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0029] Add the flocculant polyacrylamide to the pulping and papermaking wastewater of waste paper pulping and paper mills treated by Fenton oxidation at a rate of 3 mg / l, carry out gravity concentration, discharge the supernatant, and add 0.3 mg / l to the concentrated sludge Add concentrated sulfuric acid at the ratio of 1 ton / ton of absolute dry sludge, add polyacrylamide according to 0.1% of the absolute dry sludge, stir and react for 1 hour, and mix with the mixed sludge of primary sedimentation and excess sludge of waste paper pulping and paper mills The mud is mixed in a dry matter ratio of 1:5. Use a plate and frame filter press to filter under a pressure of 2 MPa until no filtrate flows out, and the water content of the mud cake is measured to be 62.1%.

Embodiment 2

[0031] Add the flocculant polyacrylamide to the pulping and papermaking wastewater of chemical wood pulp and paper mills treated by Fenton oxidation at a rate of 3mg / l, carry out gravity concentration, discharge the supernatant, and add 0.25 tons to the concentrated sludge Add concentrated sulfuric acid at the ratio of 1 ton of absolute dry sludge, add polyacrylamide according to 0.08% of the absolute dry sludge, stir and react for 1 hour, and mix with the mixed sludge of primary sedimentation and excess sludge in waste paper pulp and paper mills Mix in a dry matter ratio of 1:5. Use a plate and frame filter press to filter under a pressure of 2 MPa until no filtrate flows out, and the water content of the mud cake is measured to be 60.7%.

Embodiment 3

[0033]Add the flocculant polyacrylamide to the pulping and papermaking waste water of waste paper pulping and paper mills treated by Fenton oxidation at a rate of 3mg / l, carry out gravity concentration, discharge the supernatant, and add 0.4 to the concentrated sludge Concentrated sulfuric acid is added at the ratio of 1 ton / ton of absolute dry sludge, and polyacrylamide is added at 0.13% of the absolute dry sludge, and the reaction is stirred for 1 hour. Mix the dry matter in a ratio of 1:5. Use a plate and frame filter press to filter under a pressure of 2.0-2.5 MPa until no filtrate flows out, and the water content of the mud cake is measured to be 64.3%.

[0034] The conditioning and dehydration of other types of sludge can also achieve similar results.

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 recycling method for iron-enriched sludge of pulping and papermaking factory wastewater comprises that the pulping and papermaking wastewater obtained after fenton oxidation treatment is treated, a method of quantitative acid dissolving and agent destabilization is adopted, and the iron-enriched sludge is converted to an iron-enriched conditioner which can be used for improving the dewatering performance of pulping and papermaking factory wastewater treated mixed sludge and is recycled in-place; while the iron-enriched sludge is recycled, the cost of sludge dewatering is reduced, the original iron-enriched sludge unfavourable for sludge dewatering is converted into the agent for conditioning the sludge dewatering performance, the cost of adding the sludge dewatering conditioner is reduced, the dewatering rate of the mixed sludge is increased, and running costs of subsequent sludge incineration or landfill are decreased.

Description

technical field [0001] The invention belongs to the recycling technology of solid waste, and is a recycling method for iron-rich sludge produced when pulping and papermaking wastewater is treated by a Fenton oxidation process. Background technique [0002] In the wastewater treatment process of pulp and paper mills, in order to meet the GB3554-2008 "Discharge Standards for Water Pollutants in the Pulp and Paper Industry", enterprises often add advanced treatment processes after the secondary biological treatment of wastewater. [0003] At present, as an important advanced wastewater treatment technology, the Fenton oxidation process is widely used in the advanced treatment stage of wastewater from major pulp and paper mills. The principle of the Fenton oxidation process is to use Fe 2+ Catalytic H 2 o 2 Generates strong oxidizing hydroxyl radicals OH, initiates and propagates free radical chain reactions, and oxidizes and decomposes refractory substances in sewage. After...

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): C02F1/56C02F11/12C02F11/14C02F11/00C02F103/28
Inventor 葛强杨树成姚文峰梁继东雷平
Owner CHINA CEC ENG