CN1695832A - Method for stabilizing flying ash from burn by using soluble medicament of phosphate - Google Patents
Method for stabilizing flying ash from burn by using soluble medicament of phosphate Download PDFInfo
- Publication number
- CN1695832A CN1695832A CN 200510011651 CN200510011651A CN1695832A CN 1695832 A CN1695832 A CN 1695832A CN 200510011651 CN200510011651 CN 200510011651 CN 200510011651 A CN200510011651 A CN 200510011651A CN 1695832 A CN1695832 A CN 1695832A
- Authority
- CN
- China
- Prior art keywords
- fly ash
- incineration fly
- soluble phosphate
- phosphate
- medicament
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 229910019142 PO4 Inorganic materials 0.000 title claims abstract description 90
- 239000010452 phosphate Substances 0.000 title claims abstract description 87
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 title claims abstract description 72
- 238000000034 method Methods 0.000 title claims abstract description 49
- 230000000087 stabilizing effect Effects 0.000 title claims abstract description 11
- 239000003814 drug Substances 0.000 title claims description 47
- 229910001385 heavy metal Inorganic materials 0.000 claims abstract description 70
- 239000010881 fly ash Substances 0.000 claims description 132
- 238000002386 leaching Methods 0.000 claims description 69
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 claims description 52
- 231100000419 toxicity Toxicity 0.000 claims description 41
- 230000001988 toxicity Effects 0.000 claims description 41
- 239000000203 mixture Substances 0.000 claims description 37
- 235000011007 phosphoric acid Nutrition 0.000 claims description 26
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 26
- 229910001868 water Inorganic materials 0.000 claims description 26
- 239000003795 chemical substances by application Substances 0.000 claims description 22
- 239000004570 mortar (masonry) Substances 0.000 claims description 22
- 238000003756 stirring Methods 0.000 claims description 22
- 230000006641 stabilisation Effects 0.000 claims description 18
- 238000011105 stabilization Methods 0.000 claims description 18
- 238000002156 mixing Methods 0.000 claims description 16
- 238000006243 chemical reaction Methods 0.000 claims description 15
- 238000001723 curing Methods 0.000 claims description 12
- 229910052745 lead Inorganic materials 0.000 claims description 12
- 229910052793 cadmium Inorganic materials 0.000 claims description 11
- 238000009423 ventilation Methods 0.000 claims description 11
- 229910052725 zinc Inorganic materials 0.000 claims description 11
- 229910052802 copper Inorganic materials 0.000 claims description 9
- 229910052804 chromium Inorganic materials 0.000 claims description 8
- 229910052759 nickel Inorganic materials 0.000 claims description 8
- 239000002920 hazardous waste Substances 0.000 claims description 6
- NBIIXXVUZAFLBC-UHFFFAOYSA-L Phosphate ion(2-) Chemical compound OP([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-L 0.000 claims description 3
- NBIIXXVUZAFLBC-UHFFFAOYSA-M dihydrogenphosphate Chemical compound OP(O)([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-M 0.000 claims description 2
- 239000003153 chemical reaction reagent Substances 0.000 claims 1
- 230000008569 process Effects 0.000 abstract description 5
- 239000003053 toxin Substances 0.000 abstract 1
- 231100000765 toxin Toxicity 0.000 abstract 1
- 235000021317 phosphate Nutrition 0.000 description 63
- 229910000162 sodium phosphate Inorganic materials 0.000 description 30
- 239000001488 sodium phosphate Substances 0.000 description 30
- 235000011008 sodium phosphates Nutrition 0.000 description 30
- RYFMWSXOAZQYPI-UHFFFAOYSA-K trisodium phosphate Chemical compound [Na+].[Na+].[Na+].[O-]P([O-])([O-])=O RYFMWSXOAZQYPI-UHFFFAOYSA-K 0.000 description 30
- AJPJDKMHJJGVTQ-UHFFFAOYSA-M sodium dihydrogen phosphate Chemical compound [Na+].OP(O)([O-])=O AJPJDKMHJJGVTQ-UHFFFAOYSA-M 0.000 description 17
- 229910000403 monosodium phosphate Inorganic materials 0.000 description 16
- 235000019799 monosodium phosphate Nutrition 0.000 description 16
- -1 phosphate compound Chemical class 0.000 description 16
- 238000002474 experimental method Methods 0.000 description 11
- 239000007789 gas Substances 0.000 description 11
- 230000008859 change Effects 0.000 description 9
- BNIILDVGGAEEIG-UHFFFAOYSA-L disodium hydrogen phosphate Chemical compound [Na+].[Na+].OP([O-])([O-])=O BNIILDVGGAEEIG-UHFFFAOYSA-L 0.000 description 9
- 239000010813 municipal solid waste Substances 0.000 description 9
- 238000010668 complexation reaction Methods 0.000 description 7
- 230000000694 effects Effects 0.000 description 7
- 238000013095 identification testing Methods 0.000 description 7
- 238000005342 ion exchange Methods 0.000 description 7
- 150000003839 salts Chemical class 0.000 description 5
- 239000000126 substance Substances 0.000 description 5
- 239000002956 ash Substances 0.000 description 4
- 239000002738 chelating agent Substances 0.000 description 4
- 238000013329 compounding Methods 0.000 description 4
- 239000002699 waste material Substances 0.000 description 4
- 239000004568 cement Substances 0.000 description 3
- 230000007774 longterm Effects 0.000 description 3
- 239000002910 solid waste Substances 0.000 description 3
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical compound S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 description 2
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 2
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 description 2
- BRPQOXSCLDDYGP-UHFFFAOYSA-N calcium oxide Chemical compound [O-2].[Ca+2] BRPQOXSCLDDYGP-UHFFFAOYSA-N 0.000 description 2
- 239000000292 calcium oxide Substances 0.000 description 2
- ODINCKMPIJJUCX-UHFFFAOYSA-N calcium oxide Inorganic materials [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 description 2
- 239000013043 chemical agent Substances 0.000 description 2
- 238000006703 hydration reaction Methods 0.000 description 2
- 229910000037 hydrogen sulfide Inorganic materials 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- 229910052761 rare earth metal Inorganic materials 0.000 description 2
- 150000002910 rare earth metals Chemical class 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 159000000000 sodium salts Chemical class 0.000 description 2
- 239000003381 stabilizer Substances 0.000 description 2
- 238000004056 waste incineration Methods 0.000 description 2
- 229910017518 Cu Zn Inorganic materials 0.000 description 1
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 229910001514 alkali metal chloride Inorganic materials 0.000 description 1
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000013522 chelant Substances 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000011038 discontinuous diafiltration by volume reduction Methods 0.000 description 1
- 239000010791 domestic waste Substances 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 239000003344 environmental pollutant Substances 0.000 description 1
- 229910052588 hydroxylapatite Inorganic materials 0.000 description 1
- 239000010842 industrial wastewater Substances 0.000 description 1
- 230000003189 isokinetic effect Effects 0.000 description 1
- 238000011068 loading method Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 229910001463 metal phosphate Inorganic materials 0.000 description 1
- XYJRXVWERLGGKC-UHFFFAOYSA-D pentacalcium;hydroxide;triphosphate Chemical compound [OH-].[Ca+2].[Ca+2].[Ca+2].[Ca+2].[Ca+2].[O-]P([O-])([O-])=O.[O-]P([O-])([O-])=O.[O-]P([O-])([O-])=O XYJRXVWERLGGKC-UHFFFAOYSA-D 0.000 description 1
- 150000003013 phosphoric acid derivatives Chemical class 0.000 description 1
- 239000011574 phosphorus Substances 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 238000001637 plasma atomic emission spectroscopy Methods 0.000 description 1
- 231100000614 poison Toxicity 0.000 description 1
- 231100000719 pollutant Toxicity 0.000 description 1
- 159000000001 potassium salts Chemical class 0.000 description 1
- 239000011780 sodium chloride Substances 0.000 description 1
- 239000002689 soil Substances 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
- 238000010561 standard procedure Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 239000003440 toxic substance Substances 0.000 description 1
- 230000007306 turnover Effects 0.000 description 1
Images
Landscapes
- Processing Of Solid Wastes (AREA)
Abstract
A process for stabilizing the flying ash generated by burning by used of soluble phosphate featurs that the heavy metals contained in said flying ash can chemically react on said soluble phosphate to decrease its toxin, so the flying ash can be buried in the ground with high safety.
Description
Technical Field
The invention belongs to the field of chemical stabilization treatment of hazardous wastes, and particularly relates to a chemical agent stabilization method for solid waste incineration fly ash.
Background
At present, a large amount of garbage is incinerated every year in China. If 3% of incineration fly ash is generated in each ton of garbage, the amount of the fly ash can reach 14.71 ten thousand tons according to the total amount of the garbage 14857 ten thousand tons in 2004 and the proportion of incineration to 3.3%.
However, because the urban garbage has complex components, a large amount of toxic substances are enriched in incineration fly ash, particularly heavy metals in the garbage, such as Pb, Cd, Zn, Cu and the like, and the chemical forms of some heavy metals can be changed by incineration, so that the heavy metals can be converted into substances which are easier to migrate or have higher ecological toxicity. At present, although fly ash is effectively collected by the incineration dust removal device at home and abroad, heavy metal components in the fly ash cannot be effectively controlled, so that the fly ash should be stabilized before landfill. The 'standard for controlling pollution of domestic waste incineration' (GWKB3-2000) in China definitely lists incineration fly ash as an important dangerous waste, and needs to be treated in a harmless way.
Heavy metal control of incineration fly ash can be divided into two major methods of solidification and stabilization. Because domestic garbage in China has high plastic content and salt content, the content of alkali metal chloride in the incineration fly ash of domestic garbage in China is high, particularly the content of sodium chloride is generally high and generally accounts for 20-30% of the fly ash content, and the maximum content can reach more than 50%. If curing techniques are used, these chemicals limit the fly ash loading of acceptable incineration fly ash/cement cured products to typically less than 15-20%, which can greatly increase the volume of waste to be disposed of and thus increase disposal costs. The fly ash addition amount above this limit will greatly increase the curing time of the incineration fly ash/cement mixture to an unacceptable extent, at the same time, reduce the mechanical strength of the solidified body, increase leaching of heavy metals in the solidified body, and make it difficult to perform safe disposal for a long time.
The chemical stabilization method has a development prospect due to large volume reduction and good treatment effect. Although the chelating agent mainly used in the market at present has a good treatment effect, the use of the chelating agent is limited due to high cost, and the long-term stability of the chelate formed by the chelating agent and heavy metals is questioned due to the nature of organic matters. Other agents such as sulfide agents release hydrogen sulfide harmful gases in the long-term stabilization process, thereby causing secondary pollution.
Disclosure of Invention
The invention aims to solve the problems of high cost of chelating agents, release of harmful gas hydrogen sulfide from sulfide agents and the like of the existing stabilizing agents, and provides a chemical agent stabilizing treatment method for burning heavy metals in fly ash. The method has low cost and stable treatment effect, and does not produce secondary pollutants.
The content of heavy metals in the incineration fly ash varies according to the source of the municipal solid waste. Typically 1 to 5 parts by weight per 100 parts by weight of dry matter of the ash, more typically 2 to 3 parts by weight per 100 parts by weight of ash. The amount of Pb element present in the fly ash is generally from 0.5 to 5 parts by weight per 100 parts by weight of ash, more generally from 1 to 3 parts by weight per 100 parts by weight of ash.
The technical scheme provided by the invention is as follows:
the method for stabilizing incineration fly ash by using a soluble phosphate medicament is characterized by comprising the following steps: themethod ensures that the soluble phosphate medicament and the heavy metal in the incineration fly ash generate a stabilization chemical reaction, thereby reducing the leaching toxicity of the soluble phosphate medicament and reaching the standard of entering a hazardous waste landfill site for safe landfill, and comprises the following specific steps:
1) firstly, uniformly mixing incineration fly ash, a soluble phosphate medicament and water to fully disperse the soluble phosphate medicament in the incineration fly ash, wherein the preferable mixing mode is as follows: the method comprises the steps of uniformly stirring water and a soluble phosphate medicament to obtain a phosphate solution, and then mixing the phosphate solution with the incineration fly ash, so that a good mixing effect can be obtained, and meanwhile, the mixing and stirring time is reduced.
Wherein the weight of the soluble phosphate agent to be added is 3-10% of the dry weight of the incineration fly ash, the added water accounts for 20-30% of the total weight of the dry weight of the incineration fly ash and the soluble phosphate agent, and the soluble phosphate agent comprises one or a mixture of more of soluble phosphate normal salt, monohydrogen phosphate, dihydric phosphate or orthophosphoric acid;
when the leaching toxicity of Cd in the incineration fly ash exceeds the leaching toxicity identification standard, the weight of the soluble phosphate agent to be added is 7-10% of the dry weight of the incineration fly ash. When the total content of heavy metals Cr, Pb, Zn, Cu, Cd and Ni in the incineration fly ash reaches 3-5% of the dry weight of the incineration fly ash, the weight of the soluble phosphate agent to be added is 7-10% of the dry weight of the incineration fly ash.
2) And stirring the mixture until the mixture is completely and uniformly formed into mortar, and continuing for 5-10 minutes toensure that the heavy metal contained in the mortar and a soluble phosphate medicament fully perform chemical reactions such as ion exchange, surface complexation and the like, thereby reducing the leaching toxicity of the heavy metal.
3) And then, curing the mixture for not less than 24 hours under the natural ventilation condition, and then safely burying, wherein the preferable curing time is 24-36 hours.
During the mixing of fly ash with phosphate/phosphoric acid agents, the following chemical reactions mainly occur: (with heavy metal Pb2+For example):
the concentration of heavy metals and the content of calcium oxide contained in incineration fly ash may vary. The high content of calcium oxide can cause the alkalinity of the incineration fly ash to be too high, and if the pH value of a leachate after the incineration fly ash treatment is higher than 12, the treatment effect can be influenced, so the treatment should be carried out firstlyAnd (4) measuring the pH value of the leaching solution of the previous incineration fly ash sample. If the pH value is more than or equal to 12, selecting orthophosphoric acid as the soluble phosphate medicament or selecting the orthophosphoric acid as one of the main components; if the pH value of the incineration fly ash sample leachate is less than 12, one or a mixture of more of orthophosphoric acid normal salt, monohydrogen phosphate, dihydrogen phosphate or orthophosphoric acid can be added. Here, orthophosphoric acid provides in addition to beneficial PO4 3-Besides fixing heavy metal salt in incineration fly ash, also provides H+The alkalinity of the incineration fly ash is reduced, and the stabilization effect of heavy metals in the incineration fly ash is facilitated. Because the incineration fly ash has great difference of heavy metal types and concentrations, the compounding ratio of the medicament can be changed in the concrete implementation process without departing from the spirit and the scope of the invention.
The method of the invention is characterized in that the heavy metal salts formed by the reaction have the crystal structure of hydroxyapatite and/or phosphocalciteM5(PO4)3X，X-Is F-，Cl-，OH-，M2+Is Ca2+(in some cases Sr2+，Ba2+，Mg2+，Pb2+RE (rare earth), Na+Isokinetic substitution of Ca2+) And phosphorus exists almost exclusively in the form of phosphate in nature. Therefore, after subsequent landfill, the method has good stability and cannot cause secondary pollution to the environment. In addition, because the phosphate exists in a wide range of natural forms, the raw materials are convenient to obtain, the price of the raw materials is low, and the cost is lower than that of other stabilizing agents. Compared with other methods, the method has the advantages of simple operation and easy realization in the treatment process. At present, soluble phosphate agents have been applied to the treatment of soil contaminated by heavy metals and lead in industrial wastewater.
The experimental result shows that the method of the invention can treat various heavy metals, particularly Pb2+The stabilizing effect is good, and the standard for identifying leaching toxicity can be achieved.
Drawings
FIG. 1 is a flow chart of the incineration fly ash stabilization treatment process.
FIG. 2a shows the change of the leaching concentration of heavy metal Pb in incineration fly ash at different sodium phosphate addition amounts.
FIG. 2b shows the change of the leaching concentration of heavy metal Cd in incineration fly ash at different sodium phosphate addition amounts.
FIG. 2c shows the change of the leaching concentration of heavy metal Zn in incineration fly ash at different sodium phosphate addition amounts.
FIG. 2d shows the change of the leaching concentration of heavy metal Cu in incineration fly ash at different sodium phosphate addition amounts.
FIG. 3a shows the change of the leaching concentration of heavy metal Pb in incineration fly ash at different curing times.
FIG. 3b shows the change of the leaching concentration of heavy metal Cd in incineration fly ash under different curing times.
FIG. 3c shows the change of the leaching concentration of heavy metal Zn in incineration fly ash at different curing times.
FIG. 3d shows the change of the leaching concentration of heavy metal Cu in incineration fly ash at different curing times.
FIG. 4a shows the relationship between the leaching concentration of heavy metal Pb in incineration fly ash and the pH value of the leachate and leachates with different pH values.
FIG. 4b shows the leaching concentration of heavy metal Cd in incineration fly ash and the relationship between the pH value of the leachate and leachates with different pH values.
Detailed Description
The invention is described in detail below with reference to the drawings and preferred embodiments.
Example 1
In a certain urban garbage incineration A factory in the south, a multi-stage grate incinerator is adopted, and incineration tail gas is treated by adopting a semi-dry method. The pH value of the incineration fly ash leachate was measured to be 7.4. According to the national standard method of 'solid waste leaching toxicity leaching method' (hereinafter referred to as national standard/GB), the incineration fly ash is subjected to leaching experiments by adopting a turnover leaching method (GB5086.1-1997), the heavy metal concentration of the leachate is measured by adopting plasma emission spectroscopy (ICP), and the analysis results are shown in Table 1.
TABLE 1 incineration fly ash heavy metal leaching toxicity/mg. L-1
| Pb | Cu | Zn | Cd | Cr | Ni | |
| Fly ash sample of A plant Criteria for identifying hazardous waste (GB5085.3-1996) Hazardous waste landfill control limits (GB18598-2001) | 11.80 3 5 | 0.42 50 75 | 164.90 50 75 | 31.21 0.3 0.5 | 0.63 10 12 | 0 10 15 |
Sodium phosphate is used as a soluble phosphate medicament, and the treatment is carried out according to the treatment flow shown in figure 1, and the specific method comprises the following steps: firstly, uniformly stirring water and sodium phosphate to obtain a sodium phosphate solution, and then mixing the sodium phosphate solution with incineration fly ash, wherein the added water accounts for 30% of the total dry weight of the incineration fly ash and the sodium phosphate. And then stirring the mixture until the mixture is completely uniform into mortar, and continuing for 10 minutes to ensure that the heavy metal contained in the mortar and the soluble phosphate medicament are subjected to sufficient stabilizing chemical reaction, thereby reducing the leaching toxicity of the heavy metal. And then the mixture is maintained for 24 hours under the natural ventilation condition and then is safely buried.
The following experiments investigate the influence of different factors on the stabilizing effect of incineration fly ash soluble phosphate agents, including: sodium phosphate adding amount, maintenance time, pH related experiments and the like.
(1) Experiment method and result for influence of sodium phosphate adding amount
The leaching concentration of heavy metals of the treated incineration fly ash is shown in figures 2a to 2d under different sodium phosphate adding amounts.
As can be seen from the experimental results of fig. 2a to 2 d: when the adding amount of the sodium phosphate is 3 percent of the dry weight of the incineration fly ash, the leaching concentrations of heavy metals Pb, Cd and Zn in the incineration fly ash are respectively reduced by 97.5 percent, 91.6 percent and 95.5 percent. When the adding amount of the sodium phosphate is 3 percent of the dry weight of the incineration fly ash, the leaching concentrations of Pb and Zn in the incineration fly ash are lower than the leaching toxicity identification standard and the hazardous waste landfill control limit value, and a good stabilizing effect is obtained; when the adding amount of the sodium phosphate reaches 7 percent of the dry weight of the incineration fly ash, the leaching concentration of heavy metal Cd in the incineration fly ash can reach the corresponding standard.
(2) Experimental method and results for the influence of curing time
The leaching concentrations of heavy metals of the stabilized product after sodium phosphate treatment of incineration fly ash at different curing times are shown in fig. 3a to 3 d. From the experimental results, it can be seen that the curing time has little influence on the stabilization effect of the stabilized product, mainly because the action mechanism of the soluble sodium phosphate on the stabilization of the incineration fly ash is mainly hydration reaction, while the liquid-solid ratio on the experimental day is 30%,and no flowing water exists in the fly ash after 1d, so the hydration reaction is stopped, which is essentially different from the stabilization mechanism of the incineration fly ash in the cement treatment.
(3) pH-related Experimental methods
The method for measuring the leaching toxicity of the solid waste in China and the TCLP leaching toxicity program issued by the United states EPA do not consider the influence on the stability of the waste under the condition of pH change of a landfill environment. In this experiment, the long-term stability of the incineration fly ash phosphate stabilized product was investigated with reference to the pH-related experimental method specified in Japanese "Notification No. 13".
In the pH value-related experiment, the experiment was carried out by using sodium phosphate in an amount of 7% by weight of the dry fly ash, and the concentrations (in mg/L) of Cd and Pb in the leachate were measured by ICP and converted into the amount (in mg/kg) of heavy metal leached out per kg of waste.
The analytical results of the pH-related experiments are shown in FIGS. 4a to 4 b. As can be seen from the experimental results of fig. 4a to 4 b: when the pH value is between 2.5 and 12, the leaching concentration of heavy metal Pb in the incineration fly ash can reach the standard; when the pH value is more than 3, the leaching concentration of heavy metal Cd in the incineration fly ash can reach the corresponding standard.
Example 2
In a certain municipal refuse incineration B plant, incineration tail gas is treated by adopting a semidry method. The pH value of the incineration fly ash leachate is measured to be 12.4, and the alkalinity is higher. The leaching concentration of Pb is 36.5mg/L, other heavy metals do not exceed the standard, and the total content of the heavy metals Cr, Pb, Zn, Cu, Cd and Ni is 3 percent of the dry weight of the incineration fly ash. Orthophosphoric acid is used as a soluble phosphate agent. The specific method comprises the following steps: firstly, uniformly stirring water and orthophosphoric acid to obtain an orthophosphoric acid solution, and then mixing the orthophosphoric acid solution with incineration fly ash, wherein the weight of the orthophosphoric acid is 10% of the weight of the incineration fly ash, and the added water accounts for 20% of the total weight of the incineration fly ash and the orthophosphoric acid; and then stirring the mixture until the mixture is completely and uniformly formed into mortar, and continuing for 5-10 minutes to ensure that the heavy metal contained in the mortar and orthophosphoric acid fully perform chemical reaction, thereby reducing the leaching toxicity of the heavy metal. And then the mixture is maintained under the natural ventilation condition for 36 hours and then is safely buried. The leaching concentration of Pb in the treated product is 2.1mg/L, and the standard for identifying leaching toxicity is met.
Example 3
In a certain municipal refuse incineration C plant, incineration tail gas is treated by a semidry method. The pH value of the incineration fly ash leachate was measured to be 10.1. The leaching concentration of Pb is 13.6mg/L, and the leaching concentration of Cu is 61.3 mg/L. Sodium monohydrogen phosphate was used as the soluble phosphate agent. The specific method comprises the following steps: firstly, uniformly stirring water and sodium monohydrogen phosphate to obtain a sodium monohydrogen phosphate solution, and then mixing the sodium monohydrogen phosphate solution with incineration fly ash, wherein the adding amount of sodium monohydrogen phosphate is 5% of the dry weight of the incineration fly ash, and the adding amount of water accounts for 25% of the total dry weight of the incineration fly ash and the sodium monohydrogen phosphate; and then stirring the mixture until the mixture is completely and uniformly formed into a mortar state, and continuing for 5 minutes to ensure that the heavy metal contained in the mortar and the soluble phosphate medicament are subjected to sufficient chemical reaction, thereby reducing the leaching toxicity of the heavy metal. And then the mixture is maintained under the natural ventilation condition for 28 hours and then is safely buried. The treated product reaches the identification standard of leaching toxicity through the identification test of leaching toxicity.
Example 4
In a certain municipal refuse incineration D plant, incineration tail gas is treated by a semidry method. The pH value of the incineration fly ash leachate was measured to be 10.8. The leaching concentration of Cr is 17mg/L, and the total content of heavy metals Cr, Pb, Zn, Cu, Cd and Ni is 2 percent of the dry weight of the incineration fly ash. Sodium dihydrogen phosphate was used as a soluble phosphate agent. The specific method comprises the following steps: firstly, uniformly stirring water and sodium dihydrogen phosphate to obtain a sodium dihydrogen phosphate solution, and then mixing the sodium dihydrogen phosphate solution with incineration fly ash, wherein the adding amount of the sodium dihydrogen phosphate is 3% of the dry weight of the incineration fly ash, and the adding amount of water accounts for 24% of the total dry weight of the incineration fly ash and the sodium dihydrogen phosphate; and then stirring the mixture until the mixture is completely and uniformly formed into mortar, and continuing for 8 minutes to ensure that the heavy metal contained in the mortar and a soluble phosphate medicament fully perform chemical reactions such as ion exchange, surface complexation and the like, thereby reducing the leaching toxicity of the heavy metal. And then the mixture is maintained under the natural ventilation condition for 25 hours and then is safely buried. The treated product reaches the identification standard of leaching toxicity through the identification test of leaching toxicity.
Example 5
In a certain municipal refuse incineration E plant, incineration tail gas is treated by a semidry method. The pH value of the incineration fly ash leachate was measured to be 12.0. The leaching concentration of Cr is 17mg/L, and the total content of heavy metals Cr, Pb, Zn, Cu, Cd and Ni is 2.3 percent of the dry weight of the incineration fly ash. The soluble phosphate medicament is prepared by compounding orthophosphoric acid and sodium phosphate, wherein the sodium phosphate accounts for 30 percent, and the orthophosphoric acid accounts for 70 percent. The specific method comprises the following steps: firstly, uniformly stirring water, orthophosphoric acid and sodium phosphate to obtain a phosphate solution, and then mixing the phosphate solution with the incineration fly ash, wherein the adding amount of the soluble phosphate compound medicament is 8 percent of the dry weight of the incineration fly ash, and the adding amount of the water accounts for 20 percent of the total weight of the dry weight of the incineration fly ash and the soluble phosphate compound medicament; and then stirring the mixture until the mixture is completely and uniformly formed into mortar, and continuing for 8 minutes to ensure that the heavy metal contained in the mortar and a soluble phosphate compound medicament fully perform chemical reactions such as ion exchange, surface complexation and the like, thereby reducing the leaching toxicity of the heavy metal. And then the mixture is maintained for 24 hours under the natural ventilation condition and then is safely buried. The treated product reaches the identification standard of leaching toxicity through the identification test of leaching toxicity.
Example 6
In a certain municipal refuse incineration F plant, incineration tail gas is treated by adopting a semidry method. The pH value of the incineration fly ash leachate is measured to be 8.5. The total content of heavy metals Cr, Pb, Zn, Cu, Cd and Ni is 5 percent of the dry weight of the incineration fly ash. Sodium dihydrogen phosphate and sodium phosphate are compounded to be used as a soluble phosphate medicament, wherein the sodium phosphate accounts for 50 percent, and the orthophosphoric acid accounts for 50 percent. The specific method comprises the following steps: firstly, uniformly stirring water, sodium dihydrogen phosphate and sodium phosphate to obtain a phosphate solution, and then mixing the phosphate solution with the incineration fly ash, wherein the adding amount of a soluble phosphate compound medicament accounts for 9% of the dry weight of the incineration fly ash, and the adding amount of water accounts for 25% of the total dry weight of the incineration fly ash and the soluble phosphate compound medicament; and then stirring the mixture until the mixture is completely and uniformly formed into mortar, and continuing for 6 minutes to ensure that the heavy metal contained in the mortar and the soluble phosphate compound medicament fully perform chemical reactions such as ion exchange, surface complexation and the like, thereby reducing the leaching toxicity of the heavy metal. And then the mixture is maintained for 30 hours under the natural ventilation condition and then is safely buried. The treated product reaches the identification standard of leaching toxicity through the identification test of leaching toxicity.
Example 7
In a certain municipal refuse incineration G plant, incineration tail gas is treated by a semidry method. The pH value of the incineration fly ash leachate is measured to be 9.5. The leaching concentration of Cd is 2.3mg/L, and the leaching toxicity exceeds the leaching toxicity identification standard. Sodium phosphate monobasic, sodium dihydrogen phosphate and sodium phosphate are compounded to form the soluble phosphate medicament, wherein the sodium phosphate accounts for 20 percent, the sodium dihydrogen phosphate accounts for 50 percent and the sodium dihydrogen phosphate accounts for 30 percent. The specific method comprises the following steps: firstly, uniformly stirring water, sodium monohydrogen phosphate, sodium dihydrogen phosphate and sodium phosphate to obtain a phosphate solution, and then mixing the phosphate solution with incineration fly ash, wherein the adding amount of a soluble phosphate compound medicament is 8% of the dry weight of the incineration fly ash, and the adding amount of water accounts for 20% of the total dry weight of the incineration fly ash and the soluble phosphate compound medicament; and then stirring the mixture until the mixture is completely and uniformly formed into mortar, and continuing for 10 minutes to ensure that the heavy metal contained in the mortar and the soluble phosphate compound medicament fully perform chemical reactions such as ion exchange, surface complexation and the like, thereby reducing the leaching toxicity of the heavy metal. And then the mixture is maintained under the natural ventilation condition for 28 hours and then is safely buried. The treated product reaches the identification standard of leaching toxicity through the identification test of leaching toxicity.
Example 8
In a certain municipal refuse incineration H plant, incineration tail gas is treated by a semidry method. The pH value of the incineration fly ash leachate was measured to be 12.1. The total content of heavy metals Cr, Pb, Zn, Cu, Cd and Ni is 1 percent of the dry weight of the incineration fly ash. The soluble phosphate medicament is prepared by compounding orthophosphoric acid and sodium dihydrogen phosphate, wherein the sodium dihydrogen phosphate accounts for 50 percent, and the orthophosphoric acid accounts for 50 percent. The specific method comprises the following steps: firstly, uniformly stirring water, orthophosphoric acid and sodium phosphate to obtain a phosphate solution, and then mixing the phosphate solution with the incineration fly ash, wherein the adding amount of the soluble phosphate compound medicament accounts for 6% of the weight of the dry part of the incineration fly ash, and the adding amount of the water accounts for 22% of the total weight of the dry part of the incineration fly ash and the soluble phosphate compound medicament; and then stirring the mixture until the mixture is completely and uniformly formed into mortar, and continuing for 10 minutes to ensure that the heavy metal contained in the mortar and the soluble phosphate compound medicament fully perform chemical reactions such as ion exchange, surface complexation and the like, thereby reducing the leaching toxicity of the heavy metal. And then the mixture is maintained under the natural ventilation condition for 32 hours and then is safely buried. The treated product reaches the identification standard of leaching toxicity through the identification test of leaching toxicity.
Example 9
In a certain municipal refuse incineration I plant, incineration tail gas is treated by a semidry method. The pH value of the incineration fly ash leachate is measured to be 8.5. The total content of heavy metals Cr, Pb, Zn, Cu, Cd and Ni is 3.2 percent of the dry weight of the incineration fly ash. The soluble phosphate medicament is prepared by compounding orthophosphoric acid, sodium phosphate, sodium monohydrogen phosphate and sodium dihydrogen phosphate, wherein the orthophosphoric acid accounts for 20 percent, the sodium phosphate accounts for 30 percent, the sodium monohydrogen phosphate accounts for 25 percent, and the sodium dihydrogen phosphate accounts for 25 percent. The specific method comprises the following steps: firstly, uniformly stirring water and the soluble phosphate compound medicament to obtain a phosphate solution, and then mixing the phosphate solution with the incineration fly ash, wherein the adding amount of the soluble phosphate compound medicament is 7% of the dry weight of the incineration fly ash, and the adding amount of the water accounts for 25% of the total weight of the dry weight of the incineration fly ash and the soluble phosphate compound medicament; and then stirring the mixture until the mixture is completely and uniformly formed into mortar, and continuing for 10 minutes to ensure that the heavy metal contained in the mortar and the soluble phosphate compound medicament fully perform chemical reactions such as ion exchange, surface complexation and the like, thereby reducing the leaching toxicity of the heavy metal. And then the mixture is maintained for 24 hours under the natural ventilation condition and then is safely buried. The treated product reaches the identification standard of leaching toxicity through the identification test of leaching toxicity.
The examples given above are all represented by sodium salts as a class of soluble phosphates, in which case the sodium salts may be replaced by potassium salts or other soluble metal phosphates.
The above-described embodiments are illustrative of the nature of the invention, rather than limiting, and the scope of the invention is indicated by the claims.
Claims (7)
1. The method for stabilizing incineration fly ash by using a soluble phosphate medicament is characterized by comprising the following steps: the method ensures that the soluble phosphate medicament and the heavy metal in the incineration fly ash generate a stabilization chemical reaction, thereby reducing the leaching toxicity of the soluble phosphate medicament and reaching the standard of entering a hazardous waste landfill site for safe landfill, and comprises the following specific steps:
1) firstly, uniformly mixing incineration fly ash, a soluble phosphate medicament and water to fully disperse the soluble phosphate medicament in the incineration fly ash, wherein the weight of the soluble phosphate medicament to be added is 3-10% of the weight of the dry part of the incineration fly ash, the added water accounts for 20-30% of the total weight of the dry part of the incineration fly ash and the soluble phosphate medicament, and the soluble phosphate medicament comprises one or a mixture of more of soluble orthophosphate, monohydrogen phosphate, dihydrogen phosphate or orthophosphoric acid;
2) stirring the mixture until the mixture is completely and uniformly formed into mortar, and then continuing for 5-10 minutes to ensure that the heavy metal contained in the mortar and a soluble phosphate medicament are subjected to full stabilization chemical reaction, so that the leaching toxicity of the heavy metal is reduced;
3) and then the mixture is maintained for not less than 24 hours under the condition of natural ventilation and then is safely buried.
2. The method of stabilizing incineration fly ash with a soluble phosphate reagent according to claim 1, characterised in that: the pH value of the incineration fly ash sample leachate is measured before the step 1), and if the pH value is more than or equal to 12, the soluble phosphate medicament selects orthophosphoric acid or selects orthophosphoric acid as one of the main components.
3. The method for stabilization treatment of incineration fly ash with soluble phosphate agents according to claim 1 or 2, characterized in that: in the step 1), water and a soluble phosphate agent are stirred uniformly to obtain a phosphate solution, and then the phosphate solution is mixed with the incineration fly ash.
4. The method for stabilization treatment of incineration fly ash with soluble phosphate agents according to claim 1, 2 or 3, characterized in that: when the leaching toxicity of Cd in the incineration fly ash exceeds the leaching toxicity identification standard, the weight of the soluble phosphate agent to be added is 7-10% of the dry weight of the incineration fly ash.
5. The method for stabilization treatment of incineration fly ash with soluble phosphate agents according to claim 1, 2 or 3, characterized in that: when the total content of heavy metals Cr, Pb, Zn, Cu, Cd and Ni in the incineration fly ash reaches 3-5% of the dry weight of the incineration fly ash, the weight of the soluble phosphate agent to be added is 7-10% of the dry weight of the incineration fly ash.
6. The method for stabilization treatment of incineration fly ash with soluble phosphate agents according to claim 1, 2 or 3, characterized in that: the curing time in the step 3) is 24-36 hours.
7. The method for stabilization treatment of incineration fly ash with soluble phosphate agents according to claim 1, 2 or 3, characterized in that: the water adding amount in the step 1) accounts for 30 percent of the total weight of the dry part of the incineration fly ash and the soluble phosphate medicament.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200510011651 CN1695832A (en) | 2005-04-29 | 2005-04-29 | Method for stabilizing flying ash from burn by using soluble medicament of phosphate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200510011651 CN1695832A (en) | 2005-04-29 | 2005-04-29 | Method for stabilizing flying ash from burn by using soluble medicament of phosphate |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1695832A true CN1695832A (en) | 2005-11-16 |
Family
ID=35348813
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 200510011651 Pending CN1695832A (en) | 2005-04-29 | 2005-04-29 | Method for stabilizing flying ash from burn by using soluble medicament of phosphate |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1695832A (en) |
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100445217C (en) * | 2006-07-10 | 2008-12-24 | 同济大学 | Method for processing refuse-burning fly-ash by using magnesium ammonium phosphate sedimentation sludge |
| CN100566862C (en) * | 2006-04-11 | 2009-12-09 | 同济大学 | Heavy metal stabilization two-step method for treatment of fly ash from urban domestic refuse burning plant |
| CN101468244B (en) * | 2007-12-24 | 2012-06-27 | 中国恩菲工程技术有限公司 | Stabilization method and kneader system for flyash cement |
| CN107900068A (en) * | 2017-10-31 | 2018-04-13 | 青岛理工大学 | One kind accelerates incinerating residue stabilization method |
| CN108273825A (en) * | 2017-12-29 | 2018-07-13 | 天津壹鸣环境科技股份有限公司 | Recycling method of household garbage incineration fly ash |
| CN108593693A (en) * | 2018-01-21 | 2018-09-28 | 上海环境卫生工程设计院有限公司 | A kind of the adding of agent method and its system of the stabilizing fly ashization processing based on XRF detections |
| CN109174906A (en) * | 2018-08-31 | 2019-01-11 | 浙江理工大学 | A kind of apparatus and method solidifying flying dust |
| CN110672538A (en) * | 2019-11-13 | 2020-01-10 | 辽宁石油化工大学 | Method for reducing content of heavy metal ion lead in incineration fly ash by using phosphate solution |
| CN111872027A (en) * | 2020-07-16 | 2020-11-03 | 常熟理工学院 | Method for co-processing waste incineration fly ash and printing and dyeing waste liquid |
| CN113145606A (en) * | 2021-02-25 | 2021-07-23 | 北京旷世达资源环境工程发展中心 | Method for preparing paste slurry for resource utilization of household garbage incineration fly ash |
| CN113578920A (en) * | 2021-06-24 | 2021-11-02 | 东江环保股份有限公司 | Fly ash treatment system and treatment method |
| CN113634577A (en) * | 2021-06-11 | 2021-11-12 | 深圳市长隆科技有限公司 | Medicament for acid catalysis of heavy metals in long-period stable fly ash and use method thereof |
| CN116966470A (en) * | 2023-07-20 | 2023-10-31 | 中南大学 | Beryllium hyperstable mineralization reagent and method for hyperstable mineralization of dangerous beryllium elements in lithium slag |
-
2005
- 2005-04-29 CN CN 200510011651 patent/CN1695832A/en active Pending
Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100566862C (en) * | 2006-04-11 | 2009-12-09 | 同济大学 | Heavy metal stabilization two-step method for treatment of fly ash from urban domestic refuse burning plant |
| CN100445217C (en) * | 2006-07-10 | 2008-12-24 | 同济大学 | Method for processing refuse-burning fly-ash by using magnesium ammonium phosphate sedimentation sludge |
| CN101468244B (en) * | 2007-12-24 | 2012-06-27 | 中国恩菲工程技术有限公司 | Stabilization method and kneader system for flyash cement |
| CN107900068A (en) * | 2017-10-31 | 2018-04-13 | 青岛理工大学 | One kind accelerates incinerating residue stabilization method |
| CN108273825A (en) * | 2017-12-29 | 2018-07-13 | 天津壹鸣环境科技股份有限公司 | Recycling method of household garbage incineration fly ash |
| CN108593693B (en) * | 2018-01-21 | 2021-03-05 | 上海环境卫生工程设计院有限公司 | XRF detection-based fly ash stabilization treatment medicament adding method and system |
| CN108593693A (en) * | 2018-01-21 | 2018-09-28 | 上海环境卫生工程设计院有限公司 | A kind of the adding of agent method and its system of the stabilizing fly ashization processing based on XRF detections |
| CN109174906A (en) * | 2018-08-31 | 2019-01-11 | 浙江理工大学 | A kind of apparatus and method solidifying flying dust |
| CN110672538A (en) * | 2019-11-13 | 2020-01-10 | 辽宁石油化工大学 | Method for reducing content of heavy metal ion lead in incineration fly ash by using phosphate solution |
| CN111872027A (en) * | 2020-07-16 | 2020-11-03 | 常熟理工学院 | Method for co-processing waste incineration fly ash and printing and dyeing waste liquid |
| CN111872027B (en) * | 2020-07-16 | 2021-09-07 | 常熟理工学院 | Method for co-processing waste incineration fly ash and printing and dyeing waste liquid |
| CN113145606A (en) * | 2021-02-25 | 2021-07-23 | 北京旷世达资源环境工程发展中心 | Method for preparing paste slurry for resource utilization of household garbage incineration fly ash |
| CN113634577A (en) * | 2021-06-11 | 2021-11-12 | 深圳市长隆科技有限公司 | Medicament for acid catalysis of heavy metals in long-period stable fly ash and use method thereof |
| CN113578920A (en) * | 2021-06-24 | 2021-11-02 | 东江环保股份有限公司 | Fly ash treatment system and treatment method |
| CN116966470A (en) * | 2023-07-20 | 2023-10-31 | 中南大学 | Beryllium hyperstable mineralization reagent and method for hyperstable mineralization of dangerous beryllium elements in lithium slag |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1695832A (en) | Method for stabilizing flying ash from burn by using soluble medicament of phosphate | |
| US5193936A (en) | Fixation and stabilization of lead in contaminated soil and solid waste | |
| US6309337B1 (en) | Method of forming an insoluble phosphate mineral species | |
| US5527982A (en) | Fixation and stabilization of metals in contaminated materials | |
| CN103406333B (en) | A kind of Safe disposal method for high-concentration arsenic residue | |
| Zhang et al. | Stabilization of heavy metals in MSWI fly ash with a novel dithiocarboxylate-functionalized polyaminoamide dendrimer | |
| CN102897992B (en) | Method for solidifying and stabilizing sludge from urban sewage treatment plant | |
| CN103881727A (en) | Stable curing agent of repairing heavy metal and toxic organic matter combined polluted soil and using method of curing agent | |
| JP5440329B2 (en) | Method for producing solidified product from paper sludge incineration ash | |
| JP5205844B2 (en) | Method for producing granular material using coal ash containing harmful chemical substances, and granular material and resource material obtained by the method | |
| JP2014057949A (en) | Treatment method of pollution type waste gypsum and non-pollution type gypsum composition | |
| CN1810395A (en) | Chemical process of stabilizing fly ash from incinerating city garbage | |
| US7736291B2 (en) | Method for stabilization of heavy metals and odor control with dicalcium phosphate dihydrate powder | |
| US7530939B2 (en) | Method for stabilization of heavy metals in incinerator bottom ash and odor control with dicalcium phosphate dihydrate powder | |
| CN1827246A (en) | Heavy metal stabilization two-step method for treatment of fly ash from urban domestic refuse burning plant | |
| CN101176815A (en) | Method for stabilization processing refuse incineration flying ash | |
| CN101502840B (en) | Harmless treatment technique of solid dangerous waste | |
| JP5306524B1 (en) | Hazardous material insolubilizing material and treatment method using the same | |
| US6258018B1 (en) | Fixation and stabilization of metals in contaminated soils and materials | |
| CN104907329A (en) | Mining heavy metal polluted soil solidifying/stabilizing method | |
| JP2007283279A (en) | Pollutant treating agent containing non-calcinated peridotite principal component and method for using the same | |
| An et al. | Investigation on stabilization/solidification characteristics of lead-contaminated soil using innovative composite model of cement and soda residue | |
| JP2014097477A (en) | Harmful substance insolubilizing material and insolubilizing method of harmful substance | |
| US20070213577A1 (en) | Method for stabilization of hazardous wastes with dilute acid semi-soluble dicalcium phosphate dihydrate powder | |
| CN1285424C (en) | Process for reducing pollution of hexa covalent chromium ion |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |