A Targeted Clean Extraction Method for Phosphorus Recovery from Sludge

An extraction method and phosphorus recovery technology, applied in the field of sludge resource utilization, can solve the problems of low extraction efficiency of activated sludge, sludge can not be used directly as phosphate fertilizer, increase the complexity of phosphorus recovery process, etc., and achieve broad market application prospects, Important social and environmental benefits, the effect of little metal element interference

Active Publication Date: 2022-06-24
TONGJI UNIV
View PDF15 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, these sludges are also enriched with a large number of organic pollutants, pathogenic microorganisms, heavy metals and other substances in sewage. Therefore, sludge cannot be used directly as phosphate fertilizer, and the release of phosphorus becomes an important prerequisite for sludge phosphorus recovery.
[0004] Acid dissolution is a simple and effective sludge phosphorus extraction technology, but the co-dissolution of metals leads to subsequent phosphorus recovery, which needs to be separated and purified by ion exchange resin and other methods, which increases the complexity of the phosphorus recovery process
In addition, a large number of current research data show that acid dissolution can effectively extract inorganic phosphorus in sludge, and the extraction efficiency of digested sludge with high inorganic phosphorus content is more than 80%, but the extraction efficiency of activated sludge with high organic phosphorus content low

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
  • A Targeted Clean Extraction Method for Phosphorus Recovery from Sludge

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0032] The sludge used in this example is the residual activated sludge from biological phosphorus removal from Shanghai Bailonggang Sewage Treatment Plant, and its total solids (TS) and volatile solids (VS) are 2.45% and 1.47%, respectively, and the total phosphorus content is about 23.92mg / g TS, and the phosphorus content in the supernatant was about 40mg / L.

[0033] 1.225g of acidic ion exchange resin was added to 50g of sludge, which was shaken at 200rpm for 4h on a shaker at room temperature. After the reaction, the pH of the sludge dropped to 2.3. Use 55 mesh stainless steel sieve to obtain ion exchange resin and sludge respectively, carry out centrifugal filtration on the sludge, add calcium chloride to the filtrate to make the Ca / P molar ratio in the filtrate 1.5:1, and use 3M sodium hydroxide to adjust the pH to 9. Stir at 200 rpm for 30 minutes, stand for precipitation for 30 minutes, and recover phosphorus in the form of calcium phosphate precipitation. Finally, the...

Embodiment 2

[0039] The sludge used in this example is the residual activated sludge from biological phosphorus removal in a sewage treatment plant in Suzhou, where TS=2.40%, VS=1.56%, the total phosphorus content is about 24.64 mg / gTS, and the phosphorus content in the supernatant is about is 30mg / L.

[0040] Add 1.2g of acidic ion exchange resin to 50g of sludge, shake at 200rpm for 4h on a shaker at room temperature, and after the reaction ends, the pH of the sludge drops to 2. Use 55 mesh stainless steel sieve to obtain ion exchange resin and sludge respectively, carry out centrifugal filtration on the sludge, add calcium chloride to the filtrate to make the Ca / P molar ratio in the filtrate 1.5:1, and use 3M sodium hydroxide to adjust the pH to 9. Stir at 200 rpm for 30 minutes, stand for precipitation for 30 minutes, and recover phosphorus in the form of calcium phosphate precipitation. Finally, the used ion exchange resin is washed and regenerated with 5% hydrochloric acid.

Embodiment 3

[0045] The sludge used in this implementation is the mixed sludge of activated sludge for biological phosphorus removal from a sewage treatment plant in Suzhou and chemical sludge for enhanced phosphorus removal by iron salts, where TS=2.50%, VS=1.52%, and the total phosphorus content is about 24.50mg / g TS, the phosphorus content in the supernatant is about 35mg / L.

[0046] Add 1.25g of acidic ion exchange resin to 50g of sludge, shake at 200rpm for 4h on a shaker at room temperature, and after the reaction ends, the pH of the sludge drops to 2.5. Use 55 mesh stainless steel sieves to obtain ion exchange resin and sludge respectively, carry out centrifugal filtration on the sludge, add calcium chloride to the filtrate to make the Ca / P molar ratio in the filtrate 2:1, and use 3M sodium hydroxide to adjust the pH to 8. Stir at 200 rpm for 30 minutes, stand for precipitation for 30 minutes, and recover phosphorus in the form of calcium phosphate precipitation, and finally wash an...

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 relates to a targeted cleaning and extraction method for phosphorus recovery from sludge. The method comprises the following steps: (1) Targeted extraction of phosphorus: adding acidic ion exchange resin to the sludge, stirring to fully extract the sludge Inorganic phosphorus and organic phosphorus in; (2) ion exchange resin regeneration: sieve the mixture of sludge and resin in step (1), collect sludge and resin respectively, regenerate resin with strong acid regeneration solution, and recycle in step (1) (1); (3) Cleaning and recovery of phosphorus: centrifuge the sludge obtained in step (2), collect the residual sludge and supernatant respectively, and adjust the pH after adding calcium salt to the supernatant, in the form of calcium phosphate Cleaning Phosphorus from Recycled Sludge. Compared with the prior art, the invention has the advantages of high phosphorus release rate, little metal element interference, recyclable resin and the like.

Description

technical field [0001] The invention relates to the technical field of sludge recycling, in particular to a targeted cleaning extraction method for sludge phosphorus recovery. Background technique [0002] As a biologically essential and non-renewable resource, the long-term and stable supply of phosphorus has attracted widespread attention of all mankind. According to the statistics of the US Geological Survey, the consumption of phosphate rock is increasing at an average rate of more than 2% per year. ) and consumption rate calculation, the world's phosphate rock resources will be completely consumed within 280 years. Therefore, phosphorus resource recovery has become a strategic need for global sustainable development. [0003] As a misplaced resource, sludge is an important source of phosphorus recovery. According to incomplete statistics, about 1.3 million tons of phosphorus enter sewage treatment plants through sewage every year, which is equivalent to 15-20% of glo...

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): C02F11/00C02F11/127C01B25/32C02F101/10
CPCC02F11/00C02F11/127C01B25/32C02F2209/18C02F2101/105C02F2209/06C02F2101/203C02F2101/20C02F2101/10
Inventor 戴晓虎丁燕燕武博然
Owner TONGJI 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