CN112340912A - Method for recovering inorganic salt in ammonia desulphurization waste liquid - Google Patents
Method for recovering inorganic salt in ammonia desulphurization waste liquid Download PDFInfo
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- 239000007788 liquid Substances 0.000 title claims abstract description 181
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 title claims abstract description 85
- 239000002699 waste material Substances 0.000 title claims abstract description 80
- 238000000034 method Methods 0.000 title claims abstract description 54
- 229910021529 ammonia Inorganic materials 0.000 title claims abstract description 34
- 229910017053 inorganic salt Inorganic materials 0.000 title claims abstract description 8
- 238000006243 chemical reaction Methods 0.000 claims abstract description 57
- 238000007254 oxidation reaction Methods 0.000 claims abstract description 36
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 claims abstract description 34
- 238000006477 desulfuration reaction Methods 0.000 claims abstract description 32
- 230000023556 desulfurization Effects 0.000 claims abstract description 32
- 238000001914 filtration Methods 0.000 claims abstract description 29
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 claims abstract description 27
- 150000003839 salts Chemical group 0.000 claims abstract description 25
- 230000008569 process Effects 0.000 claims abstract description 24
- TZCXTZWJZNENPQ-UHFFFAOYSA-L barium sulfate Chemical compound [Ba+2].[O-]S([O-])(=O)=O TZCXTZWJZNENPQ-UHFFFAOYSA-L 0.000 claims abstract description 20
- 229910000029 sodium carbonate Inorganic materials 0.000 claims abstract description 17
- 150000003863 ammonium salts Chemical class 0.000 claims abstract description 16
- 230000003647 oxidation Effects 0.000 claims abstract description 16
- 159000000000 sodium salts Chemical class 0.000 claims abstract description 16
- 229910002092 carbon dioxide Inorganic materials 0.000 claims abstract description 14
- 239000001569 carbon dioxide Substances 0.000 claims abstract description 13
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 claims abstract description 12
- VGTPCRGMBIAPIM-UHFFFAOYSA-M sodium thiocyanate Chemical compound [Na+].[S-]C#N VGTPCRGMBIAPIM-UHFFFAOYSA-M 0.000 claims abstract description 12
- RQPZNWPYLFFXCP-UHFFFAOYSA-L barium dihydroxide Chemical compound [OH-].[OH-].[Ba+2] RQPZNWPYLFFXCP-UHFFFAOYSA-L 0.000 claims abstract description 11
- 229910001863 barium hydroxide Inorganic materials 0.000 claims abstract description 10
- 239000007787 solid Substances 0.000 claims abstract description 10
- 238000002156 mixing Methods 0.000 claims abstract description 8
- 230000002378 acidificating effect Effects 0.000 claims abstract description 6
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 27
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 21
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 18
- 238000001816 cooling Methods 0.000 claims description 13
- 238000005406 washing Methods 0.000 claims description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 4
- 238000004042 decolorization Methods 0.000 claims description 3
- 230000009467 reduction Effects 0.000 claims description 2
- 238000002425 crystallisation Methods 0.000 claims 1
- 230000008025 crystallization Effects 0.000 claims 1
- 238000011084 recovery Methods 0.000 abstract description 7
- 238000004064 recycling Methods 0.000 abstract description 6
- 238000004065 wastewater treatment Methods 0.000 abstract description 2
- 239000000243 solution Substances 0.000 description 13
- 235000017550 sodium carbonate Nutrition 0.000 description 12
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 description 10
- 229910052938 sodium sulfate Inorganic materials 0.000 description 10
- 239000000203 mixture Substances 0.000 description 8
- 239000012266 salt solution Substances 0.000 description 8
- 235000011152 sodium sulphate Nutrition 0.000 description 8
- 238000000967 suction filtration Methods 0.000 description 8
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 6
- 239000000126 substance Substances 0.000 description 6
- SOIFLUNRINLCBN-UHFFFAOYSA-N ammonium thiocyanate Chemical compound [NH4+].[S-]C#N SOIFLUNRINLCBN-UHFFFAOYSA-N 0.000 description 5
- 150000002500 ions Chemical class 0.000 description 5
- 239000000047 product Substances 0.000 description 5
- BHPQYMZQTOCNFJ-UHFFFAOYSA-N Calcium cation Chemical compound [Ca+2] BHPQYMZQTOCNFJ-UHFFFAOYSA-N 0.000 description 4
- 208000005156 Dehydration Diseases 0.000 description 4
- BFNBIHQBYMNNAN-UHFFFAOYSA-N ammonium sulfate Chemical compound N.N.OS(O)(=O)=O BFNBIHQBYMNNAN-UHFFFAOYSA-N 0.000 description 4
- 229910052921 ammonium sulfate Inorganic materials 0.000 description 4
- 229910001424 calcium ion Inorganic materials 0.000 description 4
- 230000018044 dehydration Effects 0.000 description 4
- 238000006297 dehydration reaction Methods 0.000 description 4
- 239000012265 solid product Substances 0.000 description 4
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 3
- 235000011130 ammonium sulphate Nutrition 0.000 description 3
- 230000008901 benefit Effects 0.000 description 3
- 229910000019 calcium carbonate Inorganic materials 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 239000007832 Na2SO4 Substances 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 239000002440 industrial waste Substances 0.000 description 2
- BWHMMNNQKKPAPP-UHFFFAOYSA-L potassium carbonate Chemical compound [K+].[K+].[O-]C([O-])=O BWHMMNNQKKPAPP-UHFFFAOYSA-L 0.000 description 2
- 239000000376 reactant Substances 0.000 description 2
- 229920006395 saturated elastomer Polymers 0.000 description 2
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical compound [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 description 1
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 1
- -1 ammonium ions Chemical class 0.000 description 1
- XYXNTHIYBIDHGM-UHFFFAOYSA-N ammonium thiosulfate Chemical compound [NH4+].[NH4+].[O-]S([O-])(=O)=S XYXNTHIYBIDHGM-UHFFFAOYSA-N 0.000 description 1
- 229910052925 anhydrite Inorganic materials 0.000 description 1
- 229910001422 barium ion Inorganic materials 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- OSGAYBCDTDRGGQ-UHFFFAOYSA-L calcium sulfate Chemical compound [Ca+2].[O-]S([O-])(=O)=O OSGAYBCDTDRGGQ-UHFFFAOYSA-L 0.000 description 1
- VDQVEACBQKUUSU-UHFFFAOYSA-M disodium;sulfanide Chemical compound [Na+].[Na+].[SH-] VDQVEACBQKUUSU-UHFFFAOYSA-M 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- XLYOFNOQVPJJNP-ZSJDYOACSA-N heavy water Substances [2H]O[2H] XLYOFNOQVPJJNP-ZSJDYOACSA-N 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 238000010979 pH adjustment Methods 0.000 description 1
- 229920001021 polysulfide Polymers 0.000 description 1
- 239000005077 polysulfide Substances 0.000 description 1
- 150000008117 polysulfides Polymers 0.000 description 1
- 229910000027 potassium carbonate Inorganic materials 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 230000036632 reaction speed Effects 0.000 description 1
- 239000012047 saturated solution Substances 0.000 description 1
- 229910052979 sodium sulfide Inorganic materials 0.000 description 1
- AKHNMLFCWUSKQB-UHFFFAOYSA-L sodium thiosulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=S AKHNMLFCWUSKQB-UHFFFAOYSA-L 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 239000011593 sulfur Substances 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 239000006228 supernatant Substances 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
Images
Classifications
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F9/00—Multistage treatment of water, waste water or sewage
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/001—Processes for the treatment of water whereby the filtration technique is of importance
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/02—Treatment of water, waste water, or sewage by heating
- C02F1/04—Treatment of water, waste water, or sewage by heating by distillation or evaporation
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/28—Treatment of water, waste water, or sewage by sorption
- C02F1/281—Treatment of water, waste water, or sewage by sorption using inorganic sorbents
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/66—Treatment of water, waste water, or sewage by neutralisation; pH adjustment
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/72—Treatment of water, waste water, or sewage by oxidation
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2101/00—Nature of the contaminant
- C02F2101/10—Inorganic compounds
- C02F2101/101—Sulfur compounds
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2101/00—Nature of the contaminant
- C02F2101/10—Inorganic compounds
- C02F2101/16—Nitrogen compounds, e.g. ammonia
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
- C02F2103/18—Nature of the water, waste water, sewage or sludge to be treated from the purification of gaseous effluents
Abstract
The invention provides a method for recovering inorganic salt in ammonia desulphurization waste liquid, belongs to the field of wastewater treatment, and can solve the problems of pollution and resource waste of the ammonia desulphurization waste liquid. The recovery method comprises the following steps: adding sodium carbonate into the ammonium salt desulfurization waste liquid, mixing with the sodium salt desulfurization waste liquid, then converting, and recovering generated carbon dioxide and ammonia gas in the process; filtering after the conversion is finished to obtain insoluble waste residues and primary clear liquid; adjusting the pH of the primary clear liquid to be acidic, and then carrying out oxidation reaction to obtain an oxidation liquid; filtering the oxidation solution to obtain elemental sulfur and secondary clear liquid; adjusting the pH value of the secondary clear liquid to be alkaline, and then filtering to obtain waste salt residues and a tertiary clear liquid; adding barium hydroxide into the third clear liquid for reaction, and then filtering to obtain solid barium sulfate and fourth clear liquid; and concentrating and crystallizing the four clear liquids, and dehydrating to obtain the sodium thiocyanate. The method is used for recycling the ammonium salt and sodium salt desulfurization waste liquid with high quality.
Description
Technical Field
The invention relates to the field of wastewater treatment, in particular to a method for recovering inorganic salt in ammonia desulphurization waste liquid.
Background
The ammonia desulphurization waste liquid is a common desulphurization waste liquid, and contains a large amount of toxic and harmful substances such as ammonium thiocyanate, ammonium thiosulfate, ammonium sulfate, ammonium polysulfide and the like. If the waste liquid is not treated and directly discharged, the problem of environmental pollution can be caused; at the same time, the recoverable compounds in such desulfurized waste streams are wasted. In view of the above, researchers have developed a technology for treating ammonia desulfurization waste liquid to purify the waste liquid and recycle sulfur-containing substances such as ammonium sulfate and ammonium thiocyanate in the waste liquid as resources. However, because the added values of ammonium sulfate and ammonium thiocyanate are low, the demand of ammonium thiocyanate in the market is basically saturated in recent years, and ammonium thiocyanate obtained by resource recovery after investment is difficult to sell, enterprises are easy to enter the difficulty of no income, great troubles are brought to the operation of the enterprises, and the method is also a practical challenge for pollution-free treatment and resource recovery of ammonia desulphurization waste liquid. Therefore, a better method for treating ammonia desulfurization waste liquid is needed to improve the resource utilization rate of inorganic salts in the waste liquid and the additional value of resource recovery products, so as to increase enterprise income.
In view of the above, there is a need to improve the process of ammonia desulfurization waste liquid in the prior art to increase the value of the recovered compounds, so as to solve the above problems.
Disclosure of Invention
The invention aims to provide a method for recycling ammonium salt and sodium salt desulfurization waste liquid with high quality.
The technical scheme for realizing the purpose of the invention is as follows:
a method for recovering inorganic salt in ammonia desulphurization waste liquid comprises the following steps:
adding sodium carbonate into the ammonium salt desulfurization waste liquid, mixing with the sodium salt desulfurization waste liquid, then converting, and recovering generated carbon dioxide and ammonia gas in the process;
filtering after the conversion is finished to obtain insoluble waste residues and primary clear liquid;
adjusting the pH value of the primary clear liquid to be acidic, and then carrying out an oxidation reaction to obtain an oxidation liquid, wherein the reaction temperature of the oxidation reaction is 90-100 ℃;
filtering the oxidation solution to obtain elemental sulfur and secondary clear liquid;
adjusting the pH value of the secondary clear liquid to be alkaline, and then filtering to obtain waste salt residues and a tertiary clear liquid;
adding barium hydroxide into the third clear liquid for reaction, and then filtering to obtain solid barium sulfate and fourth clear liquid;
and concentrating and crystallizing the four clear liquids, and dehydrating to obtain sodium thiocyanate.
As a further improvement of the present invention,
and carbon dioxide and ammonia gas generated in the conversion process are used after being washed and absorbed by water.
Adjusting the pH of the primary clear liquid to be acidic, specifically:
and adding sulfuric acid into the primary clear liquid, adjusting the pH value of the primary clear liquid to 2-3, and keeping the pH value until the oxidation reaction is finished.
Adjusting the pH of the secondary clear liquid to be alkaline, specifically:
and adding sodium hydroxide into the secondary clear liquid, and adjusting the pH value to 9-11.
And (3) adjusting the pH value of the secondary clear liquid to be alkaline, reducing the temperature of the secondary clear liquid to 80-90 ℃, and then filtering.
And adding activated carbon into the third clear liquid for decolorization, and filtering the activated carbon after the reaction is finished.
And concentrating the fourth clear liquid to a concentration of 700 g/L-800 g/L.
And crystallizing the fourth clear liquid after the concentration treatment, and simultaneously cooling the fourth clear liquid.
And keeping the temperature of the four times of clear liquid at 50-60 ℃ in the cooling treatment process.
The reaction temperature of the conversion is 60-70 ℃.
Compared with the prior art, the method for recovering the inorganic salt in the ammonia desulphurization waste liquid has the beneficial effects that:
firstly, the sodium thiocyanate and sodium sulfate products with higher added values are extracted from the ammonia desulphurization waste liquid, and the method is favorable for increasing the income of enterprises.
And secondly, the resource utilization rate of other inorganic salts in the ammonia desulphurization waste liquid is improved, the elemental sulfur in the waste liquid can be sold, and the ammonia gas can be recycled, so that the enterprise income is increased, and the desulphurization cost is reduced.
Thirdly, the method has the advantages of simple process, relatively low cost and relatively high economic benefit, can greatly improve the environment-friendly treatment of enterprises on the ammonia desulphurization waste liquid, realizes changing waste into valuable, and has important significance for the development of the resource utilization technology of inorganic salt in the ammonia desulphurization waste liquid.
Drawings
FIG. 1 is a process flow diagram of the method for recovering inorganic salts from an ammonia desulfurization waste liquid according to the present invention.
Detailed Description
The present invention is described in detail with reference to the embodiments shown in the drawings, but it should be understood that these embodiments are not intended to limit the present invention, and those skilled in the art should understand that functional, methodological, or structural equivalents or substitutions made by these embodiments are within the scope of the present invention.
Referring to fig. 1, fig. 1 is a process flow diagram of a method for recovering inorganic salts from an ammonia desulfurization waste liquid according to the present invention, including the steps of:
and S1, adding sodium carbonate into the ammonium salt desulfurization waste liquid, mixing with the sodium salt desulfurization waste liquid, then carrying out conversion, and recovering the generated carbon dioxide and ammonia gas in the process.
Preferably, the conversion temperature is 60 ℃ to 70 ℃. Within the temperature range, the reaction speed is correspondingly improved along with the improvement of the reaction temperature, and the conversion rate is slightly improved; in addition, within the temperature range, the heating temperature can be just kept by utilizing the industrial waste heat, so that the effective utilization of the industrial waste heat is realized, and the energy is saved.
Because a large amount of ammonium ions exist in the ammonium salt desulfurization waste liquidSeed, and Ca2+、S2-、S2O3 2-、SO4 2-The resource recovery of the ammonium salt is too saturated, the profit is low, and the ammonium salt and the sodium salt desulfurization waste liquid need different treatment processes for treatment, so the method selects to convert the ammonium salt into the sodium salt, and particularly converts the ammonium salt into the sodium salt by adjusting the pH to be alkaline (wherein, the pH can be adjusted by alkaline substances such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate and the like). Meanwhile, a small amount of impurity ions such as calcium ions exist in the waste liquid, the calcium ions in the waste liquid can be well removed by using carbonate, and in order to avoid introducing other ions, sodium carbonate is selected, and the price of the sodium carbonate is relatively low, so that the pH value can be adjusted and the impurity ions such as the calcium ions in the waste liquid can be removed by selecting the sodium carbonate. In addition, sodium carbonate is added into the ammonium salt desulfurization waste liquid firstly, so that the sodium carbonate can be converted into sodium salt in one step, and the sodium salt can be treated in the subsequent treatment steps, so that the treatment difficulty is simplified. The carbon dioxide and ammonia gas generated by the reaction can be utilized after being washed and absorbed, so that the economic value is increased. Since both carbon dioxide and ammonia are soluble in water, it is preferred that the solution is also subjected to a heat treatment during this process to take advantage of the recovery of carbon dioxide and ammonia.
The reaction equation occurring in this step is as follows:
(NH4)2S+Na2CO3→(NH4)2CO3+Na2S；
(NH4)2S2O3+Na2CO3→(NH4)2CO3+Na2S2O3；
CaSO4+Na2CO3→CaCO3↓+(NH4)2SO4；
(NH4)2CO3→2NH3↑+CO2↑+H2O。
and S2, filtering after the conversion is finished to obtain insoluble waste residues and primary clear liquid.
The step is mainly used for filtering insoluble substances such as waste residues in the desulfurization waste liquid, such as materials, dust and other substances mixed in the desulfurization waste liquid, and calcium carbonate precipitate. Preferably, in order to improve the filtering effect, the invention can select a suction filtration mode for filtering.
S3, adjusting the pH value of the primary clear liquid to be acidic, and then carrying out oxidation reaction to obtain an oxidation liquid, wherein the reaction temperature of the oxidation reaction is 90-100 ℃.
Compared with a higher reaction temperature, the reaction temperature of 90-100 ℃ can achieve a better oxidation reaction effect, and the reaction temperature is easy to realize and can save energy.
Preferably, sulfuric acid (preferably dilute sulfuric acid, such as dilute sulfuric acid with a concentration of 20%) can be added into the primary clear liquid, and the pH value of the primary clear liquid is adjusted to 2-3 and is kept until the whole oxidation reaction is finished. Because the desulfurization waste liquid contains sulfate ions, the pH of the primary clear liquid is adjusted by adding sulfuric acid in order to avoid introducing new elements.
The chemical reaction equation that occurs for this step is as follows:
2Na2S+O2+H2O→4NaOH+S↓；
2NaOH+H2SO4→Na2SO4+2H2O；
2Na2S2O3+O2→2Na2SO4+S↓。
s4, filtering the oxidation liquid to obtain elemental sulfur and secondary clear liquid.
And (3) filtering filter residues after the oxidation reaction, namely the elemental sulfur and a large amount of solid sodium sulfate which reaches the dissolution limit and cannot be dissolved again, and recovering, wherein secondary clear liquid comprises saturated solution of sodium sulfate. The purity of the recovered elemental sulfur and solid sodium sulfate is high, the enterprise profit is improved by changing waste into valuable, and the reasonable recovery and utilization of resources are realized.
And S5, adjusting the pH value of the secondary clear liquid obtained in the step S4 to be alkaline, and then filtering to obtain waste salt residues and a tertiary clear liquid.
Preferably, the secondary clear solution may be concentrated prior to adjusting the pH.
And preferably, adding sodium hydroxide into the secondary clear liquid, and adjusting the pH value to 9-11. Since the desulfurization waste liquid of the present invention is currently a sodium salt desulfurization waste liquid, sodium hydroxide is selected in order to avoid introducing new elements when the pH thereof is adjusted to be alkaline.
Furthermore, because the pH adjustment process is an exothermic reaction, the temperature is preferably reduced to 80-90 ℃, and then the filtration treatment is carried out. The temperature reduction may be performed by heat exchange such as water cooling, which is not limited in the present invention.
And S6, adding barium hydroxide into the third clear liquid for reaction, and filtering to obtain solid barium sulfate and a fourth clear liquid.
Because the barium sulfate is a water-insoluble substance, barium hydroxide is selectively added, and the introduced barium ions can be removed by filtration after reaction.
The chemical reaction equation that occurs for this step is as follows:
Na2SO4+Ba(OH)2→BaSO4↓+2NaOH。
further, the invention adds barium hydroxide and active carbon into the third clear liquid for decolorization, and then filters the active carbon after the reaction is finished.
And S7, concentrating and crystallizing the fourth clear liquid obtained in the step S6, and dehydrating to obtain sodium thiocyanate.
Further, the four times of clear liquid is concentrated to the concentration of 700 g/L-800 g/L, and the concentration is improved, so that the subsequent treatment is facilitated.
Furthermore, the supernatant after the concentration treatment is crystallized and cooled at the same time. Specifically, the temperature of the clear liquid is kept at 50-60 ℃ in the cooling process.
It will be understood by those skilled in the art that the amount of the reactant materials added in the present invention depends on the ion content of the solution to be reacted therewith, and the amount of the reactant materials added can be determined according to the ion concentration of the solution, and the present invention is not limited to specific values.
The present invention will be described in detail with reference to examples.
Example 1:
the method for recovering inorganic salts from ammonia desulphurization waste liquid provided by the embodiment comprises the following steps:
s1, adding soda ash into the ammonium salt solution, mixing with the sodium salt solution, placing the mixture into a conversion kettle for conversion at the conversion temperature of 60 ℃, recovering generated carbon dioxide and ammonia gas in the conversion process, and recycling after washing and absorbing;
s2, after the conversion is finished, placing the mixture in a suction filtration tank to obtain insoluble waste residues such as calcium carbonate and the like and primary clear liquid;
s3, adjusting the pH of the primary clear liquid to 2 by using dilute sulfuric acid, and placing the primary clear liquid in an oxidation kettle for oxidation reaction to obtain oxidation liquid, wherein the reaction temperature of the oxidation reaction is 90 ℃;
s4, placing the oxidized liquid obtained in the step S3 in a filter tank, and filtering to obtain elemental sulfur, solid sodium sulfate and secondary clear liquid;
s5, placing the secondary clear liquid obtained in the step S4 in a concentration kettle for concentration, adjusting the pH to 9 by using sodium hydroxide, and placing the secondary clear liquid in a cooling tank to be cooled to 80 ℃ in the process of adjusting the pH or after adjusting the pH; finally, placing the cooled solution in a filter tank to obtain waste salt residue and tertiary clear liquid;
s6, adding activated carbon and barium hydroxide into the tertiary clear liquid obtained in the S5, and reacting for a period of time; then placing the solution in a filter tank to obtain filter residue barium sulfate and fourth clear liquid;
s7, putting the four times of clear liquid obtained in the step S6 into a concentration kettle, concentrating the clear liquid to 700g/L, and cooling the clear liquid to 60 ℃; finally, carrying out suction filtration and dehydration treatment to obtain a solid product sodium thiocyanate.
The purity of the product sodium thiocyanate obtained in the step of S7 was checked to be 96%.
Example 2:
the method for recovering inorganic salts from ammonia desulphurization waste liquid provided by the embodiment comprises the following steps:
s1, adding soda ash into the ammonium salt solution, mixing with the sodium salt solution, placing the mixture into a conversion kettle for conversion at the conversion temperature of 65 ℃, recovering generated carbon dioxide and ammonia gas in the conversion process, and recycling after washing and absorbing;
s2, after the conversion is finished, placing the mixture in a suction filtration tank to obtain insoluble waste residues and primary clear liquid;
s3, adjusting the pH of the primary clear liquid to 2.5 by using dilute sulfuric acid, and placing the primary clear liquid in an oxidation kettle for oxidation reaction to obtain an oxidation liquid, wherein the reaction temperature of the oxidation reaction is 95 ℃;
s4, placing the oxidized liquid obtained in the step S3 in a filter tank, and filtering to obtain elemental sulfur, solid sodium sulfate and secondary clear liquid;
s5, placing the secondary clear liquid obtained in the step S4 in a concentration kettle for concentration, adjusting the pH to 10 by using sodium hydroxide, and placing the secondary clear liquid in a cooling tank to be cooled to 83 ℃ in the process of adjusting the pH or after adjusting the pH; finally, placing the cooled solution in a filter tank to obtain waste salt residue and tertiary clear liquid;
s6, adding activated carbon and barium hydroxide into the tertiary clear liquid obtained in the S5, and reacting for a period of time; then placing the solution in a filter tank to obtain filter residue barium sulfate and fourth clear liquid;
s7, putting the four clear liquids obtained in the step S6 into a concentration kettle, concentrating the four clear liquids to 750g/L, and cooling the four clear liquids to 53 ℃; and finally, carrying out filter pressing dehydration treatment to obtain a solid product sodium thiocyanate.
The purity of the product sodium thiocyanate obtained in the step of S7 was checked to be 95.4%.
Example 3:
the method for recovering inorganic salts from ammonia desulphurization waste liquid provided by the embodiment comprises the following steps:
s1, adding soda ash into the ammonium salt solution, mixing with the sodium salt solution, placing the mixture into a conversion kettle for conversion at the conversion temperature of 68 ℃, recovering generated carbon dioxide and ammonia gas in the conversion process, and recycling after washing and absorbing;
s2, after the conversion is finished, placing the mixture in a suction filtration tank to obtain insoluble waste residues and primary clear liquid;
s3, adjusting the pH of the primary clear liquid to 2.8 by using dilute sulfuric acid, and placing the primary clear liquid in an oxidation kettle for oxidation reaction to obtain an oxidation liquid, wherein the reaction temperature of the oxidation reaction is 98 ℃;
s4, placing the oxidized liquid obtained in the step S3 in a filter tank, and filtering to obtain elemental sulfur, solid sodium sulfate and secondary clear liquid;
s5, placing the secondary clear liquid obtained in the step S4 in a concentration kettle for concentration, adjusting the pH to 10.5 by using sodium hydroxide, and placing the secondary clear liquid in a cooling tank to be cooled to 85 ℃ in the process of adjusting the pH or after adjusting the pH; finally, placing the cooled solution in a filter tank to obtain waste salt residue and tertiary clear liquid;
s6, adding activated carbon and barium hydroxide into the tertiary clear liquid obtained in the S5, and reacting for a period of time; then placing the solution in a filter tank to obtain filter residue barium sulfate and fourth clear liquid;
s7, putting the four clear liquids obtained in the step S6 into a concentration kettle, concentrating the four clear liquids to 780g/L, and cooling the four clear liquids to 58 ℃; finally, carrying out suction filtration and dehydration treatment to obtain a solid product sodium thiocyanate.
The purity of the product sodium thiocyanate obtained in the step of S7 was checked to be 94.8%.
Example 4
The method for recovering inorganic salts from ammonia desulphurization waste liquid provided by the embodiment comprises the following steps:
s1, adding soda ash into the ammonium salt solution, mixing with the sodium salt solution, placing the mixture into a conversion kettle for conversion at the conversion temperature of 70 ℃, recovering generated carbon dioxide and ammonia gas in the conversion process, and recycling after washing and absorbing;
s2, after the conversion is finished, placing the mixture in a suction filtration tank to obtain insoluble waste residues and primary clear liquid;
s3, adjusting the pH of the primary clear liquid to 3 by using dilute sulfuric acid, and placing the primary clear liquid in an oxidation kettle for oxidation reaction to obtain an oxidation liquid, wherein the reaction temperature of the oxidation reaction is 100 ℃;
s4, placing the oxidized liquid obtained in the step S3 in a filter tank, and filtering to obtain elemental sulfur, solid sodium sulfate and secondary clear liquid;
s5, placing the secondary clear liquid obtained in the step S4 in a concentration kettle for concentration, adjusting the pH to 11 by using sodium hydroxide, and placing the secondary clear liquid in a cooling tank to be cooled to 90 ℃ in the process of adjusting the pH or after adjusting the pH; finally, placing the cooled solution in a filter tank to obtain waste salt residue and tertiary clear liquid;
s6, adding activated carbon and barium hydroxide into the tertiary clear liquid obtained in the S5, and reacting for a period of time; then placing the solution in a filter tank to obtain filter residue barium sulfate and fourth clear liquid;
s7, putting the four times of clear liquid obtained in the step S6 into a concentration kettle, concentrating to 800g/L, and cooling to 50 ℃; finally, carrying out suction filtration and dehydration treatment to obtain a solid product sodium thiocyanate.
The above-listed detailed description is only a specific description of a possible embodiment of the present invention, and they are not intended to limit the scope of the present invention, and equivalent embodiments or modifications made without departing from the technical spirit of the present invention should be included in the scope of the present invention.
It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.
Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.
Claims (10)
1. A method for recovering inorganic salt in ammonia desulphurization waste liquid is characterized by comprising the following steps:
adding sodium carbonate into the ammonium salt desulfurization waste liquid, mixing with the sodium salt desulfurization waste liquid, then converting, and recovering generated carbon dioxide and ammonia gas in the process;
filtering after the conversion is finished to obtain insoluble waste residues and primary clear liquid;
adjusting the pH value of the primary clear liquid to be acidic, and then carrying out an oxidation reaction to obtain an oxidation liquid, wherein the reaction temperature of the oxidation reaction is 90-100 ℃;
filtering the oxidation solution to obtain elemental sulfur and secondary clear liquid;
adjusting the pH value of the secondary clear liquid to be alkaline, and then filtering to obtain waste salt residues and a tertiary clear liquid;
adding barium hydroxide into the third clear liquid for reaction, and then filtering to obtain solid barium sulfate and fourth clear liquid;
and concentrating and crystallizing the four clear liquids, and dehydrating to obtain sodium thiocyanate.
2. The method for recovering inorganic salts from ammonia desulfurization waste liquid according to claim 1, wherein carbon dioxide and ammonia gas generated in the conversion process are absorbed by washing with water and then utilized.
3. The method for recovering inorganic salts from ammonia desulfurization waste liquid according to claim 1, wherein the pH of the primary clear liquid is adjusted to be acidic, specifically:
and adding sulfuric acid into the primary clear liquid, adjusting the pH value of the primary clear liquid to 2-3, and keeping the pH value until the oxidation reaction is finished.
4. The method for recovering inorganic salts from ammonia desulfurization waste liquid according to claim 1, wherein the pH of the secondary clear liquid is adjusted to be alkaline, specifically:
and adding sodium hydroxide into the secondary clear liquid, and adjusting the pH value to 9-11.
5. The method for recovering inorganic salts from ammonia desulfurization waste liquid according to claim 1 or 4, wherein the temperature of the secondary clear liquid is reduced to 80 to 90 ℃ after the pH of the secondary clear liquid is adjusted to be alkaline, and then the secondary clear liquid is filtered.
6. The method for recovering inorganic salts from ammonia desulfurization waste liquid according to claim 1, further comprising adding activated carbon to the third clear liquid to perform decolorization treatment, and filtering the activated carbon after the reaction is completed.
7. The method for recovering inorganic salts from ammonia desulfurization waste liquid according to claim 1, wherein the fourth-time clear liquid is concentrated to a concentration of 700g/L to 800 g/L.
8. The method for recovering inorganic salts from ammonia desulfurization waste liquid according to claim 1, wherein the crystallization treatment is performed on the fourth-time clear liquid after the concentration treatment, and the temperature reduction treatment is also performed thereon.
9. The method for recovering inorganic salts from ammonia desulfurization waste liquid as claimed in claim 8, wherein the temperature of the fourth clear liquid is maintained at 50-60 ℃ in the cooling treatment process.
10. The method for recovering inorganic salts from ammonia desulfurization waste liquid according to claim 1, wherein the reaction temperature for the conversion is 60 ℃ to 70 ℃.
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| CN116730297A (en) * | 2023-06-09 | 2023-09-12 | 北京康仑循环科技有限公司 | Process for recycling desulfurization waste liquid of coke oven gas |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1424255A (en) * | 2002-12-24 | 2003-06-18 | 江苏德邦化学工业集团有限公司 | Method for qualifying industrial ammonium chloride products |
| DE102007014504A1 (en) * | 2006-03-30 | 2007-10-04 | Gea Messo Gmbh | Eluting sodium thiocyanate from a solution containing secondary salt comprises adding alcohol to a partial stream of the solution, separating sodium thiocyanate and partially reintroducing the partial stream into the elution process |
| CN101823730A (en) * | 2010-05-25 | 2010-09-08 | 安徽工业大学 | Method for simultaneously producing sodium thiocyanate and ammonium carbonate |
| CN103601219A (en) * | 2013-11-27 | 2014-02-26 | 安徽工业大学 | Method for extracting sodium carbonate and sodium thiocyanate from sodium alkali desulfurization liquid waste by using causticization-acidification method |
| CN103979578A (en) * | 2014-05-21 | 2014-08-13 | 黄进前 | New process for preparing sodium thiocyanate |
| US20150093309A1 (en) * | 2013-09-30 | 2015-04-02 | Pushpito Kumar Ghosh | Method Of Recycling Of By-Products For The Production Of Soda Ash And Ammonium Sulphate |
| CN109052429A (en) * | 2018-10-16 | 2018-12-21 | 河北诚信九天医药化工有限公司 | A kind of production technology of high-quality sodium sulfocyanate |
-
2020
- 2020-09-29 CN CN202011047645.2A patent/CN112340912A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1424255A (en) * | 2002-12-24 | 2003-06-18 | 江苏德邦化学工业集团有限公司 | Method for qualifying industrial ammonium chloride products |
| DE102007014504A1 (en) * | 2006-03-30 | 2007-10-04 | Gea Messo Gmbh | Eluting sodium thiocyanate from a solution containing secondary salt comprises adding alcohol to a partial stream of the solution, separating sodium thiocyanate and partially reintroducing the partial stream into the elution process |
| CN101823730A (en) * | 2010-05-25 | 2010-09-08 | 安徽工业大学 | Method for simultaneously producing sodium thiocyanate and ammonium carbonate |
| US20150093309A1 (en) * | 2013-09-30 | 2015-04-02 | Pushpito Kumar Ghosh | Method Of Recycling Of By-Products For The Production Of Soda Ash And Ammonium Sulphate |
| CN103601219A (en) * | 2013-11-27 | 2014-02-26 | 安徽工业大学 | Method for extracting sodium carbonate and sodium thiocyanate from sodium alkali desulfurization liquid waste by using causticization-acidification method |
| CN103979578A (en) * | 2014-05-21 | 2014-08-13 | 黄进前 | New process for preparing sodium thiocyanate |
| CN109052429A (en) * | 2018-10-16 | 2018-12-21 | 河北诚信九天医药化工有限公司 | A kind of production technology of high-quality sodium sulfocyanate |
Non-Patent Citations (2)
| Title |
|---|
| 朱鸿民: "《冶金研究 2010年》", 31 December 2010, 北京：冶金工业出版社 * |
| 王斌等: "化学法ADA脱硫废液中提取硫氰酸钠的实验研究", 《安徽工业大学》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116730297A (en) * | 2023-06-09 | 2023-09-12 | 北京康仑循环科技有限公司 | Process for recycling desulfurization waste liquid of coke oven gas |
| CN116730297B (en) * | 2023-06-09 | 2024-04-05 | 北京康仑循环科技有限公司 | Process for recycling desulfurization waste liquid of coke oven gas |
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