CN109467115B - Separation and impurity removal process for carbide slag desulfurized gypsum slurry - Google Patents
Separation and impurity removal process for carbide slag desulfurized gypsum slurry Download PDFInfo
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- CN109467115B CN109467115B CN201811486116.5A CN201811486116A CN109467115B CN 109467115 B CN109467115 B CN 109467115B CN 201811486116 A CN201811486116 A CN 201811486116A CN 109467115 B CN109467115 B CN 109467115B
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
- C01F11/00—Compounds of calcium, strontium, or barium
- C01F11/46—Sulfates
- C01F11/468—Purification of calcium sulfates
Abstract
The invention relates to a separation and impurity removal process for carbide slag desulfurized gypsum slurry, which comprises the following specific steps: (1) adding a catalyst into the gypsum slurry and stirring; (2) introducing the mixture into a hydraulic cyclone separation device, introducing the underflow slurry into a primary settling tank, stirring for primary settling, and removing upper-layer suspended impurities; (3) introducing the bottom slurry in the primary settling tank into a secondary settling tank, stirring for secondary settling, and introducing circulating water into the stirring tank for stirring and layering; adding a catalyst into the mixture, stirring, introducing circulating water into the stirring tank, continuously stirring, stirring for layering, and removing upper-layer suspended impurities; (4) after the secondary separation is finished, dehydrating the slurry at the bottom of the secondary settling tank to obtain gypsum; the invention discloses a separation and impurity removal process for carbide slag desulfurized gypsum slurry, which can separate black suspended impurities in the gypsum slurry to the maximum extent, improve the purity of gypsum and reduce the water content of the gypsum.
Description
Technical Field
The invention relates to a separation and impurity removal process for carbide slag desulfurized gypsum slurry, belonging to the field of separation and impurity removal processes.
Background
The carbide slag is used as a desulfurizer for flue gas desulfurization, and the carbide slag is used as the desulfurizer, so that the flue gas desulfurization operation cost can be effectively reduced. Among the prior art, the wet industrial waste who discharges in a large number in acetylene in-process is prepared for the carbide to carbide sediment, and the ash that generates in partial impurity and the flue gas constantly accumulates in the absorption tower, can form impurity, and such impurity not only diameter is little, is difficult to separate, and the adhesion is great moreover, adsorbs easily on the gypsum surface to produce certain influence to the separation of raw materials, consequently, how fast effectual separates the problem that becomes numerous producers will solve to the desulfurization gypsum thick liquid.
Disclosure of Invention
The invention provides a process for separating and removing impurities from carbide slag desulfurized gypsum slurry, aiming at overcoming the defects in the prior art.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
a separation and impurity removal process for carbide slag desulfurized gypsum slurry is characterized by comprising the following specific steps:
(1) adding a catalyst into the gypsum slurry, stirring at 50-60 ℃ for 30-50 minutes, standing for 60-90 minutes, heating the mixture to 70-75 ℃, and stirring for 15-20 minutes;
(2) standing the mixture, after cooling to 20-50 ℃, introducing the mixture to hydraulic cyclone separation, introducing the underflow slurry into a primary settling tank, stirring for primary settling, and removing upper-layer suspended impurities;
(3) introducing the bottom slurry in the primary settling tank into a secondary settling tank, stirring for secondary settling, introducing circulating water into the stirring tank, continuously stirring for 40-50 minutes, and stirring for layering; adding a catalyst into the mixture, stirring for 40-50 minutes at 65-70 ℃, introducing circulating water into the stirring tank, continuously stirring for 20-25 minutes, stirring for layering, and removing suspended impurities on the upper layer;
(4) and after the secondary separation is finished, dehydrating the slurry at the bottom of the secondary settling tank to obtain gypsum.
As a modification of the invention, the mass ratio of the gypsum slurry to the catalyst in the step (1) is 7: 3; the mass ratio of the gypsum slurry in the step (1) to the catalyst in the step (3) is 6: 1.
As a modification of the invention, the stirring speed in the step (1) is 180-190 rpm.
As a modification of the invention, the stirring speed of the primary sedimentation in the step (2) is 120-150 r/min.
As a modification of the invention, the stirring speed of the secondary sedimentation in the step (3) is 80-110 r/min.
As an improvement of the invention, the catalyst in the step (1) and the step (3) comprises the following components in parts by weight: 80-100 parts of activated carbon, 40-55 parts of pine oil, 30-40 parts of pine oil, 5-6 parts of methyl isobutyl carbinol and 13-20 parts of camphor oil.
As an improvement of the invention, the preparation process of the catalyst comprises the following steps:
1) weighing activated carbon, terpineol oil, pine oil, methyl isobutyl carbinol and camphor oil according to a formula;
2) putting the activated carbon into an acid solution, standing for 20-30 minutes at 60-70 ℃, and taking out;
3) drying the activated carbon at the temperature of 200-210 ℃ for 1-2 hours;
4) mixing pine oil, methyl isobutyl carbinol and camphor oil, and stirring for 20-30 minutes at 30-40 ℃;
5) adding the activated carbon generated in the step 3) into the mixture generated in the step 4), heating the mixture to 210 ℃ and 230 ℃, stirring for 30-40 minutes, and filtering;
6) drying the activated carbon at the temperature of 280-300 ℃ for 1-2 hours;
7) the catalyst is prepared by roasting the activated carbon under 350-400% of water vapor for 1-2 hours.
As a modification of the invention, the acid concentration in the acid solution in the step 2) is H+The content of the active carbon is 0.5-0.8 mol/L.
Compared with the prior art, the invention has the following beneficial effects because the technology is adopted:
the invention discloses a separation and impurity removal process for carbide slag desulfurized gypsum slurry, which can separate black suspended impurities in the gypsum slurry to the maximum extent, improve the purity of gypsum and reduce the water content of the gypsum.
Detailed Description
The present invention will be further illustrated with reference to the following specific embodiments.
Example 1:
a technology for separating and removing impurities from carbide slag desulfurized gypsum slurry comprises the following specific steps:
(1) adding a catalyst into the gypsum slurry, stirring for 50 minutes at 50 ℃, standing for 60 minutes, heating the mixture to 75 ℃, and stirring for 15 minutes;
(2) standing the mixture, introducing the mixture into a first-stage settling tank after the mixture is cooled to 50 ℃, introducing the underflow slurry into a hydraulic cyclone separation, stirring the underflow slurry to perform first-stage settling, and removing upper-layer suspended impurities;
(3) introducing the bottom slurry in the primary settling tank into a secondary settling tank, stirring for secondary settling, introducing circulating water into the stirring tank, continuously stirring for 40 minutes, and stirring for layering; adding a catalyst into the mixture, stirring for 40 minutes at 70 ℃, introducing circulating water into the stirring tank, continuously stirring for 25 minutes, stirring for layering, and removing suspended impurities on the upper layer;
(4) and after the secondary separation is finished, dehydrating the slurry at the bottom of the secondary settling tank to obtain gypsum.
The mass ratio of the gypsum slurry to the catalyst in the step (1) is 7: 3; the mass ratio of the gypsum slurry in the step (1) to the catalyst in the step (3) is 6: 1.
The stirring speed in the step (1) is 180 r/min.
And (3) the stirring speed of the primary sedimentation in the step (2) is 150 r/min.
And (4) the stirring speed of the secondary sedimentation in the step (3) is 80 r/min.
The catalyst in the step (1) and the step (3) comprises the following components in parts by weight: 100 parts of activated carbon, 40 parts of pine oil, 5 parts of methyl isobutyl carbinol and 20 parts of camphor oil.
The preparation process of the catalyst comprises the following steps:
1) weighing activated carbon, terpineol oil, pine oil, methyl isobutyl carbinol and camphor oil according to a formula;
2) putting the activated carbon into an acid solution, standing at 60 ℃ for 30 minutes, and taking out;
3) drying the activated carbon at 200 ℃ for 2 hours;
4) mixing the pine oil, the methyl isobutyl carbinol and the camphor oil, and stirring for 30 minutes at the temperature of 30 ℃;
5) adding the activated carbon generated in the step 3) into the mixture generated in the step 4), heating the mixture to 210 ℃, stirring for 40 minutes, and filtering;
6) drying the activated carbon at 280 ℃ for 2 hours;
7) the activated carbon was calcined under 350% steam for 2 hours to make the catalyst.
The concentration of the acid in the acid solution in the step 2) is H+The amount is 0.5 mol/L.
The gypsum slurry from the carbide slag desulfurization process has the slurry density of 1.26g/cm and the solid content of 28 percentThe gypsum is separated and purified, and the obtained gypsum has the water content of 7.28 percent, the purity of 98.3 percent and black suspended substances3The content is 0.27%.
Example 2:
a technology for separating and removing impurities from carbide slag desulfurized gypsum slurry comprises the following specific steps:
(1) adding a catalyst into the gypsum slurry, stirring at 60 ℃ for 30 minutes, standing for 90 minutes, heating the mixture to 70 ℃, and stirring for 20 minutes;
(2) standing the mixture, introducing the mixture into a first-stage settling tank after the mixture is cooled to 20 ℃, performing first-stage settling by stirring the underflow slurry after the mixture is subjected to hydraulic cyclone separation, and removing upper-layer suspended impurities;
(3) introducing the bottom slurry in the primary settling tank into a secondary settling tank, stirring for secondary settling, introducing circulating water into the stirring tank, continuously stirring for 50 minutes, and stirring for layering; adding a catalyst into the mixture, stirring for 50 minutes at 65 ℃, introducing circulating water into the stirring tank, continuously stirring for 20 minutes, stirring for layering, and removing suspended impurities on the upper layer;
(4) and after the secondary separation is finished, dehydrating the slurry at the bottom of the secondary settling tank to obtain gypsum.
The mass ratio of the gypsum slurry to the catalyst in the step (1) is 7: 3; the mass ratio of the gypsum slurry in the step (1) to the catalyst in the step (3) is 6: 1.
The stirring speed in the step (1) is 190 revolutions per minute.
And (3) the stirring speed of the primary sedimentation in the step (2) is 120 r/min.
And (4) the stirring speed of the secondary sedimentation in the step (3) is 110 r/min.
The catalyst in the step (1) and the step (3) comprises the following components in parts by weight: 80 parts of activated carbon, 55 parts of pine oil, 30 parts of pine oil, 6 parts of methyl isobutyl carbinol and 13 parts of camphor oil.
The preparation process of the catalyst comprises the following steps:
1) weighing activated carbon, terpineol oil, pine oil, methyl isobutyl carbinol and camphor oil according to a formula;
2) putting the activated carbon into an acid solution, standing for 20 minutes at 70 ℃, and taking out;
3) drying the activated carbon at 210 ℃ for 1 hour;
4) mixing the pine oil, the methyl isobutyl carbinol and the camphor oil, and stirring for 20 minutes at 40 ℃;
5) adding the activated carbon generated in the step 3) into the mixture generated in the step 4), heating the mixture to 230 ℃, stirring for 30 minutes, and filtering;
6) drying the activated carbon at 300 ℃ for 1 hour;
7) the activated carbon was calcined under 400% steam for 1 hour to make the catalyst.
The concentration of the acid in the acid solution in the step 2) is H+The amount is 0.8 mol/L.
Gypsum slurry from a carbide slag desulfurization process having a slurry density of 1.25g/cm3And the solid content is 27.3 percent, the separation and impurity removal are carried out in the embodiment, the water content of the obtained gypsum is 7.32 percent, the purity is 98.2 percent, and the content of black suspended matters is 0.35 percent.
Example 3:
a technology for separating and removing impurities from carbide slag desulfurized gypsum slurry comprises the following specific steps:
(1) adding a catalyst into the gypsum slurry, stirring at 55 ℃ for 30 minutes, standing for 70 minutes, heating the mixture to 70 ℃, and stirring for 15 minutes;
(2) standing the mixture, introducing the mixture into a first-stage settling tank after the mixture is cooled to 30 ℃, introducing the underflow slurry into a hydraulic cyclone separation, stirring the underflow slurry to perform first-stage settling, and removing upper-layer suspended impurities;
(3) introducing the bottom slurry in the primary settling tank into a secondary settling tank, stirring for secondary settling, introducing circulating water into the stirring tank, continuously stirring for 45 minutes, and stirring for layering; adding a catalyst into the mixture, stirring for 45 minutes at 68 ℃, introducing circulating water into the stirring tank, continuously stirring for 20 minutes, stirring for layering, and removing suspended impurities on the upper layer;
(4) and after the secondary separation is finished, dehydrating the slurry at the bottom of the secondary settling tank to obtain gypsum.
The mass ratio of the gypsum slurry to the catalyst in the step (1) is 7: 3; the mass ratio of the gypsum slurry in the step (1) to the catalyst in the step (3) is 6: 1.
The stirring speed in the step (1) is 180 r/min.
And (3) the stirring speed of the primary sedimentation in the step (2) is 120 r/min.
And (4) the stirring speed of the secondary sedimentation in the step (3) is 80 r/min.
The catalyst in the step (1) and the step (3) comprises the following components in parts by weight: 90 parts of activated carbon, 50 parts of pine oil, 35 parts of pine oil, 5 parts of methyl isobutyl carbinol and 20 parts of camphor oil.
The preparation process of the catalyst comprises the following steps:
1) weighing activated carbon, terpineol oil, pine oil, methyl isobutyl carbinol and camphor oil according to a formula;
2) putting the activated carbon into an acid solution, standing at 60 ℃ for 30 minutes, and taking out;
3) drying the activated carbon at 200 ℃ for 1 hour;
4) mixing the pine oil, the methyl isobutyl carbinol and the camphor oil, and stirring for 20 minutes at 40 ℃;
5) adding the activated carbon generated in the step 3) into the mixture generated in the step 4), heating the mixture to 230 ℃, stirring for 30 minutes, and filtering;
6) drying the activated carbon at 300 ℃ for 1 hour;
7) the activated carbon was calcined under 400% steam for 1 hour to make the catalyst.
The concentration of the acid in the acid solution in the step 2) is H+The amount is 0.8 mol/L.
Gypsum slurry from a carbide slag desulfurization process having a slurry density of 1.24g/cm3Solids content 272%, the present example was conducted to separate and remove impurities, and the obtained gypsum had a water content of 7.45%, a purity of 97.8%, and a content of black suspended matter of 0.33%.
The above-mentioned embodiments are merely preferred embodiments of the present invention, and should not be construed as limiting the present invention, and the scope of the present invention should be defined by the claims, and equivalents including technical features of the claims, i.e., equivalent modifications within the scope of the present invention.
Claims (5)
1. A separation and impurity removal process for carbide slag desulfurized gypsum slurry is characterized by comprising the following specific steps:
(1) adding a catalyst into the gypsum slurry, stirring at 50-60 ℃ for 30-50 minutes, standing for 60-90 minutes, heating the mixture to 70-75 ℃, and stirring for 15-20 minutes;
(2) standing the mixture, after cooling to 20-50 ℃, introducing the mixture to hydraulic cyclone separation, introducing the underflow slurry into a primary settling tank, stirring for primary settling, and removing upper-layer suspended impurities;
(3) introducing the bottom slurry in the primary settling tank into a secondary settling tank, stirring for secondary settling, introducing circulating water into the secondary settling tank, continuously stirring for 40-50 minutes, and stirring for layering; adding a catalyst into the mixture, stirring for 40-50 minutes at 65-70 ℃, introducing circulating water into the secondary settling tank, continuously stirring for 20-25 minutes, stirring for layering, and removing suspended impurities on the upper layer;
after the secondary separation is finished, dehydrating the slurry at the bottom of the secondary settling tank to obtain gypsum;
the mass ratio of the gypsum slurry to the catalyst in the step (1) is 7: 3; the mass ratio of the gypsum slurry in the step (1) to the catalyst in the step (3) is 6: 1;
the preparation process of the catalyst comprises the following steps:
1) weighing the following raw materials in parts by weight: 80-100 parts of activated carbon, 40-55 parts of pine oil, 30-40 parts of pine oil, 5-6 parts of methyl isobutyl carbinol and 13-20 parts of camphor oil;
2) putting the activated carbon into an acid solution, standing for 20-30 minutes at 60-70 ℃, and taking out;
3) drying the activated carbon at the temperature of 200-210 ℃ for 1-2 hours;
4) mixing pine oil, methyl isobutyl carbinol and camphor oil, and stirring for 20-30 minutes at 30-40 ℃;
5) adding the activated carbon generated in the step 3) into the mixture generated in the step 4), heating the mixture to 210 ℃ and 230 ℃, stirring for 30-40 minutes, and filtering;
6) drying the activated carbon at the temperature of 280-300 ℃ for 1-2 hours;
7) the catalyst is prepared by roasting the activated carbon under 350-400% of water vapor for 1-2 hours.
2. The carbide slag desulfurized gypsum slurry separation and impurity removal process according to claim 1, characterized in that: the stirring speed in the step (1) is 180-190 r/min.
3. The carbide slag desulfurized gypsum slurry separation and impurity removal process according to claim 1, characterized in that: the stirring speed of the primary sedimentation in the step (2) is 120-150 r/min.
4. The carbide slag desulfurized gypsum slurry separation and impurity removal process according to claim 1, characterized in that: and (4) the stirring speed of the secondary sedimentation in the step (3) is 80-110 r/min.
5. The carbide slag desulfurized gypsum slurry separation and impurity removal process according to claim 1, characterized in that: the concentration of the acid in the acid solution in the step 2) is H+The content of the active carbon is 0.5-0.8 mol/L.
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| CN113135585A (en) * | 2021-04-22 | 2021-07-20 | 深圳市青青源科技有限公司 | Preparation method for reducing organic matter content in desulfurized gypsum |
| CN113510002B (en) * | 2021-09-13 | 2021-12-17 | 中国科学院过程工程研究所 | Method and system device for removing impurities in carbide slag through micro-nano bubble coupling hydrocyclone separation |
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| FI120819B (en) * | 2008-04-09 | 2010-03-31 | Kemira Oyj | Procedure for cleaning plaster |
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