CN103183457A - Method for recovering phosphorus in sewage sludge - Google Patents
Method for recovering phosphorus in sewage sludge Download PDFInfo
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- CN103183457A CN103183457A CN 201110446835 CN201110446835A CN103183457A CN 103183457 A CN103183457 A CN 103183457A CN 201110446835 CN201110446835 CN 201110446835 CN 201110446835 A CN201110446835 A CN 201110446835A CN 103183457 A CN103183457 A CN 103183457A
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- mud
- phosphorus
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- 238000000034 method Methods 0.000 title claims abstract description 47
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 title claims abstract description 45
- 229910052698 phosphorus Inorganic materials 0.000 title claims abstract description 39
- 239000011574 phosphorus Substances 0.000 title claims abstract description 39
- 239000010801 sewage sludge Substances 0.000 title abstract 6
- 239000006228 supernatant Substances 0.000 claims abstract description 18
- 238000011084 recovery Methods 0.000 claims abstract description 17
- 238000010438 heat treatment Methods 0.000 claims abstract description 15
- 239000002253 acid Substances 0.000 claims abstract description 10
- 238000001556 precipitation Methods 0.000 claims abstract description 10
- 230000029087 digestion Effects 0.000 claims abstract description 9
- 239000011777 magnesium Substances 0.000 claims abstract description 9
- 239000013535 sea water Substances 0.000 claims abstract description 8
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 claims abstract description 6
- 229910052749 magnesium Inorganic materials 0.000 claims abstract description 6
- 238000003756 stirring Methods 0.000 claims description 31
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 9
- 239000007788 liquid Substances 0.000 claims description 9
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 9
- 238000006243 chemical reaction Methods 0.000 claims description 7
- 239000010802 sludge Substances 0.000 claims description 7
- 239000012716 precipitator Substances 0.000 claims description 4
- 230000002459 sustained effect Effects 0.000 claims description 4
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical compound [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 claims description 3
- 238000010304 firing Methods 0.000 claims description 3
- 238000002604 ultrasonography Methods 0.000 claims description 3
- 230000008901 benefit Effects 0.000 abstract description 4
- 238000005265 energy consumption Methods 0.000 abstract description 2
- UXVMQQNJUSDDNG-UHFFFAOYSA-L Calcium chloride Chemical compound [Cl-].[Cl-].[Ca+2] UXVMQQNJUSDDNG-UHFFFAOYSA-L 0.000 abstract 1
- 239000001110 calcium chloride Substances 0.000 abstract 1
- 229910001628 calcium chloride Inorganic materials 0.000 abstract 1
- 235000011148 calcium chloride Nutrition 0.000 abstract 1
- MXZRMHIULZDAKC-UHFFFAOYSA-L ammonium magnesium phosphate Chemical compound [NH4+].[Mg+2].[O-]P([O-])([O-])=O MXZRMHIULZDAKC-UHFFFAOYSA-L 0.000 description 6
- 229910052567 struvite Inorganic materials 0.000 description 6
- 239000001506 calcium phosphate Substances 0.000 description 4
- 229910000389 calcium phosphate Inorganic materials 0.000 description 4
- 235000011010 calcium phosphates Nutrition 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- QORWJWZARLRLPR-UHFFFAOYSA-H tricalcium bis(phosphate) Chemical compound [Ca+2].[Ca+2].[Ca+2].[O-]P([O-])([O-])=O.[O-]P([O-])([O-])=O QORWJWZARLRLPR-UHFFFAOYSA-H 0.000 description 4
- 239000002351 wastewater Substances 0.000 description 4
- 229910017958 MgNH Inorganic materials 0.000 description 3
- 239000000047 product Substances 0.000 description 3
- 230000001105 regulatory effect Effects 0.000 description 3
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 238000005406 washing Methods 0.000 description 2
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 1
- YUWBVKYVJWNVLE-UHFFFAOYSA-N [N].[P] Chemical compound [N].[P] YUWBVKYVJWNVLE-UHFFFAOYSA-N 0.000 description 1
- 239000004411 aluminium Substances 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910021529 ammonia Inorganic materials 0.000 description 1
- XKMRRTOUMJRJIA-UHFFFAOYSA-N ammonia nh3 Chemical compound N.N XKMRRTOUMJRJIA-UHFFFAOYSA-N 0.000 description 1
- 238000002306 biochemical method Methods 0.000 description 1
- 229910052791 calcium Inorganic materials 0.000 description 1
- 239000011575 calcium Substances 0.000 description 1
- 159000000007 calcium salts Chemical class 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 239000003337 fertilizer Substances 0.000 description 1
- BHEPBYXIRTUNPN-UHFFFAOYSA-N hydridophosphorus(.) (triplet) Chemical compound [PH] BHEPBYXIRTUNPN-UHFFFAOYSA-N 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- QJGQUHMNIGDVPM-UHFFFAOYSA-N nitrogen group Chemical group [N] QJGQUHMNIGDVPM-UHFFFAOYSA-N 0.000 description 1
- 150000003016 phosphoric acids Chemical class 0.000 description 1
- 238000007747 plating Methods 0.000 description 1
- 239000001205 polyphosphate Substances 0.000 description 1
- 235000011176 polyphosphates Nutrition 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 239000010865 sewage Substances 0.000 description 1
- 230000000192 social effect Effects 0.000 description 1
- 239000002689 soil Substances 0.000 description 1
- 238000002525 ultrasonication Methods 0.000 description 1
- 238000004065 wastewater treatment Methods 0.000 description 1
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Abstract
The invention discloses a method for recovering phosphorus in sewage sludge. The method comprises the following steps: digesting a certain amount of the sewage sludge at first so as to allow the phosphorus to be released to a solution from the sewage sludge, wherein a digestion method can be one selected from the group consisting of an ultrasonic method, a heating method and an acid addition method or be a combined method of the heating method and the acid addition method ultrasonic method; and then, recovering the phosphorus resource in supernatant of the sewage sludge having undergone digestion, wherein a recovery method is to recover phosphorus in the supernatant of the sewage sludge through precipitation with a CaCl2 solution or through precipitation with seawater used as a magnesium source. With such a technical scheme, the method provided by the invention has the advantages of a simple process, low energy consumption, economic efficiency and social significance.
Description
Technical field
The present invention relates to sewage and reclaim, relate in particular to a kind of method that reclaims phosphorus in the mud.
Background technology
Phosphorus not only has important use in agriculture production and is worth, and in industry, medicine, biology, also playing the part of considerable role, be widely used at everyways such as feed, metal treatment, plating processing, material of construction, flame-retarding fire-extinguishing, petrochemical complex, geological prospectings.Therefore, human very huge to its demand.Yet current all signs show that the product that phosphorus is relevant continues deliverability and can descend, and production cost but constantly rises.Phosphorus in the water body is mainly derived from ight soil, washing composition and some trade effluent, mainly exists with, poly-phosphate and three kinds of forms of organophosphorus.By the phosphoric acid salt of washing composition discharging account for total phosphorus pollution load about.Present nitrogenous phosphorus wastewater treatment method is a lot, but shortcoming is in various degree all arranged, and especially for containing high strength ammonia and phosphatic waste water, general biochemical method treatment effect is not ideal enough, and chemistry such as conventional aluminium, iron, calcium salt dephosphorization.Intermediate processing will produce a large amount of reluctant mud.Since the sixties in 20th century, people begin one's study and use magnesium ammonium phosphate (MAP) precipitator method and remove and reclaim nitrogen phosphorus in the waste water.
MAP precipitator method dephosphorization principle is to NH
4 +Add Mg in the water
2+And PO
4 3-Or HPO
4 3-, make it and NH
4 +Generate indissoluble double salt MgNH
4PO
46H
2O (be called for short MAP crystallization), the equation of face as follows, thus remove ammonia nitrogen in the waste water.This method also can be used for Removal of Phosphorus in Wastewater.The main chemical reactions equation is as follows:
Mg
2++PO
4 3-+NH
4 ++6H
2O＝MgNH
4PO
4·6H
2O↓
Mg
2++HPO
4 3-+NH
4 ++6H
2O＝MgNH
4PO
4·6H
2O↓+H
+
2002, United States Patent (USP) trademark office disclosed a kind of method that reclaims element phosphor from the mud that contains water, dirt and element phosphor.MS. investigator such as Sa Fen is melted mud with high temperature earlier, and the weight that adds then in contained element phosphor in the mud is about the 0.5%-3% oxygenant, and is about 75%-400% water in the weight of mud.The above mixture of continuously stirring until the external phase of forming element phosphorus, separates to purify obtaining phosphorus at last from this mixture.
On the whole, above mud phosphorus reclaims technology and has advantages such as phosphorous recovery height, mud decrement, but still has some problems: as 1. the energy consumption generation is expensive; 2. technical process complexity; 3. product is comparatively single; 4. the environmental pollution that may cause.
Summary of the invention
Purpose of the present invention is intended to overcome the deficiencies in the prior art, provides a kind of technology simple, reliable, and the method for phosphorus in the higher recovery mud of the rate of recovery.
Realize that technical scheme of the present invention comprises the steps:
Earlier a certain amount of mud is cleared up earlier, made phosphorus from mud, be discharged in the solution; The method of clearing up can be supersonic method, heating method, add a kind of or heating method of acid system and add two kinds of associatings of acid system; Concrete operations are as follows:
1. supersonic method: add water in mud, stir, and regulate pH to 10-11 with NaOH, ultrasound condition is: the every work of ultrasonic wave 4 seconds intermittently 1 second then, continuous firing 60 minutes;
2. heating method: add water in mud, stir, the temperature of heating remains on 60-90 ℃, and the time of heating is 30 minutes to 60 minutes;
3. add acid system: in mud, add 10%HCl, stir, sustained reaction 2 hours;
4. heat and sour integrated process: add 2-4%HCl in mud, stir, the temperature of heating remains on 60-90 ℃, sustained reaction 2 hours;
Then, to reclaiming through phosphor resource in the supernatant liquid of clearing up back mud; The method that reclaims can be with CaCl
2Solution precipitation reclaims the phosphorus of mud upper strata in the stillness of night, perhaps is the phosphorus in the magnesium source precipitation recovery mud supernatant liquor with the seawater; Concrete operations are as follows:
1. CaCl
2Solution deposit: get the supernatant liquid behind the sludge digestion, add proper C aCl
2Solution, and stir with agitator, adjusting pH is 10-11, reacts after 5-10 minute, stops to stir, and leaves standstill;
2. the magnesium source precipitator method: get the supernatant liquid behind the sludge digestion, add an amount of seawater and ammonium solution, stir with agitator, adjusting pH is 10-11, reacts after 15-20 minute, stops to stir, and leaves standstill;
The temperature of the phosphorus in the above-mentioned recovery mud supernatant liquor is 10-35 ℃.
The frequency that above-mentioned agitator stirs is 100-120rpm.
Advantage of the present invention is:
(1) ultrasonication, the method that heats, adds the associating of acid and hot acid are discharged in the solution phosphorus from mud, carry out the recovery of phosphorus again from solution, and technology is simple relatively, and it is low to consume energy.
(2) the present invention adopts the calcium phosphate precipitation method to reclaim phosphorus, with CaCl
2For the calcium source generates calcium phosphate, reclaim for the mode of magnesium source generation magnesium ammonium phosphate realizes the phosphorus precipitation in the solution with the seawater, because seawater is a kind of extremely cheap and inexhaustible resources for coastal cities, can save the cost of precipitation reagent, therefore have certain economic benefits and social effect.
(3) to reclaim the product that phosphorus finally obtains be calcium phosphate or magnesium ammonium phosphate to the calcium phosphate precipitation method, can be used as fertilizer utilization, realizes the recirculation of phosphor resource.
Description of drawings
Fig. 1 is process flow sheet of the present invention.
Embodiment
Below in conjunction with example the present invention is further elaborated, as shown in Figure 1.
As one embodiment of the present of invention, earlier with adding water in a certain amount of mud, stir, and regulate pH to 10 with NaOH, ultrasound condition is: work 4s intermittently 1 second, continuous firing 60 minutes;
Then, get the supernatant liquid behind the sludge digestion, add proper C aCl
2Solution, and stir with agitator, regulating pH is 10, react after 5-10 minute, stops stirring, leaves standstill;
The temperature of the phosphorus in the above-mentioned recovery mud supernatant liquor is 25 ℃.
The frequency that above-mentioned agitator stirs is 120rpm.
The rate of recovery of phosphorus can reach 80% in the mud.
As an alternative embodiment of the invention,, stir reaction 2h earlier with adding 10%HCl in a certain amount of mud; Then, get the supernatant liquid behind the sludge digestion, add an amount of seawater and ammonium solution, stir with agitator, regulating pH is 10, react after 15 minutes, stops stirring, leaves standstill;
The temperature of the phosphorus in the above-mentioned recovery mud supernatant liquor is 10 ℃.
The frequency that above-mentioned agitator stirs is 100rpm.
The rate of recovery of phosphorus can reach 75% in the mud.
As an alternative embodiment of the invention, earlier with adding 2%HCl in a certain amount of mud, stir, the temperature of heating remains on 90 ℃, reaction 2h;
Then, get the supernatant liquid behind the sludge digestion, add proper C aCl
2Solution, and stir with agitator, regulating pH is 11, react after 5 minutes, stops stirring, leaves standstill;
The temperature of the phosphorus in the above-mentioned recovery mud supernatant liquor is 35 ℃.
The frequency that above-mentioned agitator stirs is 100rpm.
The rate of recovery of phosphorus can reach 82% in the mud.
The above, it only is preferred embodiment of the present invention, be not that the present invention is done any pro forma restriction, any technical solution of the present invention content that do not break away from,, all still belong in the scope of technical solution of the present invention any simple modification, equivalent variations and modification that above embodiment does according to technical spirit of the present invention.
Claims (3)
1. method that reclaims phosphorus in the mud, it is characterized in that it comprises the steps: earlier a certain amount of mud to be cleared up earlier, make phosphorus from mud, be discharged in the solution, the method of clearing up can be supersonic method, heating method, add a kind of or heating method of acid system and add two kinds of associatings of acid system that concrete operations are as follows:
1. supersonic method: add water in mud, stir, and regulate pH to 10-11 with NaOH, ultrasound condition is: the every work of ultrasonic wave 4 seconds intermittently 1 second then, continuous firing 60 minutes;
2. heating method: add water in mud, stir, the temperature of heating remains on 60-90 ℃, and the time of heating is 30 minutes to 60 minutes;
3. add acid system: in mud, add 10%HCl, stir, sustained reaction 2 hours;
4. heat and sour integrated process: add 2-4%HCl in mud, stir, the temperature of heating remains on 60-90 ℃, sustained reaction 2 hours;
Then, to reclaiming through phosphor resource in the supernatant liquid of clearing up back mud; The method that reclaims can be with CaCl
2Solution precipitation reclaims the phosphorus of mud upper strata in the stillness of night, perhaps is the phosphorus in the magnesium source precipitation recovery mud supernatant liquor with the seawater; Concrete operations are as follows:
1. CaCl
2Solution deposit: get the supernatant liquid behind the sludge digestion, add proper C aCl
2Solution, and stir with agitator, adjusting pH is 10-11, reacts after 5 to 10 minutes, stops to stir, and leaves standstill;
2. the magnesium source precipitator method: get the supernatant liquid behind the sludge digestion, add an amount of seawater and ammonium solution, stir with agitator, adjusting pH is 10-11, reacts after 15-20 minute, stops to stir, and leaves standstill.
2. the method for phosphorus in the recovery mud as claimed in claim 1, it is characterized in that: the temperature of the phosphorus in the described recovery mud supernatant liquor is 10-35 ℃.
3. the method for phosphorus in the recovery mud as claimed in claim 1 is characterized in that: the frequency that described agitator stirs is 100-120rpm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201110446835 CN103183457A (en) | 2011-12-27 | 2011-12-27 | Method for recovering phosphorus in sewage sludge |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201110446835 CN103183457A (en) | 2011-12-27 | 2011-12-27 | Method for recovering phosphorus in sewage sludge |
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| Publication Number | Publication Date |
|---|---|
| CN103183457A true CN103183457A (en) | 2013-07-03 |
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103641283A (en) * | 2013-11-26 | 2014-03-19 | 华南理工大学 | Method of economically recycling phosphor from excess sludge |
| CN105502866A (en) * | 2016-02-05 | 2016-04-20 | 无锡国联环保能源集团有限公司 | Method and system for recycling struvite from sludge |
| CN105948234A (en) * | 2016-06-27 | 2016-09-21 | 郑州大学 | Recycling method of phosphorus-containing aerobic granular sludge |
| CN107082541A (en) * | 2017-03-16 | 2017-08-22 | 贵州民族大学 | A kind of system and method for reclaiming protein and phosphorus in sewage disposal plant excess sludge |
| CN107777857A (en) * | 2017-06-23 | 2018-03-09 | 西南大学 | Heat treatment combine shearing improves the method that sludge releases phosphorus ability |
| CN109020149A (en) * | 2018-09-15 | 2018-12-18 | 东莞理工学院 | A kind of sludge Resource recoveryization utilizes method and resource utilization device |
| CN109354003A (en) * | 2018-09-20 | 2019-02-19 | 江苏理工学院 | A kind of recovery method of phosphorus in cyanobacteria |
| CN112520852A (en) * | 2020-04-08 | 2021-03-19 | 同济大学 | Method for removing and recovering phosphorus in sewage |
| CN112979109A (en) * | 2021-01-28 | 2021-06-18 | 海宁一泓环境科技有限公司 | Method for in-situ treatment of river sediment phosphorus |
| CN113087325A (en) * | 2021-03-27 | 2021-07-09 | 同济大学 | Targeted clean extraction method for sludge phosphorus recovery |
-
2011
- 2011-12-27 CN CN 201110446835 patent/CN103183457A/en active Pending
Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103641283B (en) * | 2013-11-26 | 2016-01-06 | 华南理工大学 | A kind of method reclaiming phosphorus from excess sludge of economy |
| CN103641283A (en) * | 2013-11-26 | 2014-03-19 | 华南理工大学 | Method of economically recycling phosphor from excess sludge |
| CN105502866B (en) * | 2016-02-05 | 2018-10-09 | 无锡华光锅炉股份有限公司 | A kind of method and system recycling guanite from sludge |
| CN105502866A (en) * | 2016-02-05 | 2016-04-20 | 无锡国联环保能源集团有限公司 | Method and system for recycling struvite from sludge |
| CN105948234A (en) * | 2016-06-27 | 2016-09-21 | 郑州大学 | Recycling method of phosphorus-containing aerobic granular sludge |
| CN107082541A (en) * | 2017-03-16 | 2017-08-22 | 贵州民族大学 | A kind of system and method for reclaiming protein and phosphorus in sewage disposal plant excess sludge |
| CN107777857A (en) * | 2017-06-23 | 2018-03-09 | 西南大学 | Heat treatment combine shearing improves the method that sludge releases phosphorus ability |
| CN109020149A (en) * | 2018-09-15 | 2018-12-18 | 东莞理工学院 | A kind of sludge Resource recoveryization utilizes method and resource utilization device |
| CN109020149B (en) * | 2018-09-15 | 2021-07-09 | 东莞理工学院 | A kind of sludge recycling resource utilization method and recycling resource utilization device |
| CN109354003A (en) * | 2018-09-20 | 2019-02-19 | 江苏理工学院 | A kind of recovery method of phosphorus in cyanobacteria |
| CN112520852A (en) * | 2020-04-08 | 2021-03-19 | 同济大学 | Method for removing and recovering phosphorus in sewage |
| CN112520852B (en) * | 2020-04-08 | 2022-06-14 | 同济大学 | Method for removing and recovering phosphorus in sewage |
| CN112979109A (en) * | 2021-01-28 | 2021-06-18 | 海宁一泓环境科技有限公司 | Method for in-situ treatment of river sediment phosphorus |
| CN113087325A (en) * | 2021-03-27 | 2021-07-09 | 同济大学 | Targeted clean extraction method for sludge phosphorus recovery |
| CN113087325B (en) * | 2021-03-27 | 2022-06-24 | 同济大学 | A Targeted Clean Extraction Method for Phosphorus Recovery from Sludge |
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Application publication date: 20130703 |