Integrated device and method for capturing carbon dioxide based on basic calcite to strengthen sulfur autotrophic nitrogen removal and synergistically remove phosphorus, fluorine and sulfur

Abstract

The invention discloses an integrated device and method for capturing carbon dioxide based on basic calcite to strengthen sulfur autotrophic nitrogen removal and synergistically remove phosphorus, fluorine and sulfur, and belongs to the technical field of carbon capture. The invention designs an integrated device for capturing carbon dioxide based on basic calcite to reinforce sulfur autotrophic nitrogen removal and synergistically remove phosphorus, fluorine and sulfur. The device is formed by sequentially connecting a CO2 capturing device, a water collecting tank, a sulfur autotrophic reactor and a sedimentation tank. The device can be matched with basic calcite to realize efficient removal of nitrogen, phosphorus, fluorine and sulfur in wastewater, the application range of the basic calcite is successfully expanded, and meanwhile, the efficient treatment performance of the basic calcite is also found. And an economic and efficient treatment method is developed for a sulfur autotrophic denitrification technology.

Description

Technical Field

[0001] The invention relates to an integrated device and method for enhancing sulfur autotrophic denitrification and coordinated removal of phosphorus, fluorine and sulfur based on capturing carbon dioxide with basic calcite, belonging to the technical field of carbon capture. Background Art

[0002] With the acceleration of industrialization, greenhouse gas emissions continue to increase, among which carbon dioxide is one of the main greenhouse gases, which has a significant impact on global warming. Basic calcite is a waste product of the paper industry, in which the CaCO3 content is as high as 80.5% or more, and the remaining components are mainly NaCl, and the remaining components include SiO2, Al2O3, etc. At present, basic calcite is an industrial waste with a huge output, but the fields where it can be applied are very scarce, so it is particularly important to expand its resource utilization channels.

[0003] Sulfur autotrophic denitrification (SADN) is a wastewater treatment technology that uses reduced sulfur as an electron donor to generate CO3 2- 、HCO3 - Or CO2 as an inorganic carbon source to achieve nitrogen removal from sewage. The advantage of this technology is that there is no need to add additional carbon sources, thereby reducing treatment costs and showing great application potential in achieving deep denitrification. However, the bacterial flora in the sulfur autotrophic denitrification process consumes the alkalinity in the system during the denitrification reaction, so the alkalinity needs to be supplemented, but this will increase the operating cost of the entire treatment process. Because basic calcite contains a high proportion of calcium carbonate, it can react with carbon dioxide in water to produce HCO3 - , the following is the reaction equation: CaCO3+H2O+CO2=Ca(HCO3)2, so using basic calcite to provide inorganic carbon source and alkalinity for SADN is a feasible resource direction, which will open up the resource path of basic calcite and promote the development of sulfur autotrophic denitrification technology. In addition, the sulfur autotrophic denitrification process will produce SO4 2- , which hinders the further development of this technology, so it is also necessary to find a method for simultaneous removal of SO4 2- method. Summary of the invention

[0004] In order to solve the above problems, the present invention provides an integrated device based on capturing carbon dioxide with basic calcite to enhance sulfur autotrophic denitrification and coordinated removal of phosphorus, fluorine and sulfur. The device is composed of a CO2 capture device, a water collection tank, a sulfur autotrophic reactor and a sedimentation tank connected in sequence.

[0005] Furthermore, the CO2 capture device is columnar, with a water inlet for the capture device provided below the column body and a water outlet for the capture device provided above the column body; a CO2 gas pipe inlet and a waste residue discharge port are provided at the bottom of the CO2 capture device, and the CO2 gas pipe inlet is connected to an aeration device inside the CO2 capture device; a feed port and an agitator are provided at the top of the CO2 capture device; a solid-liquid separator is provided at the upper middle position inside the CO2 capture device.

[0006] Furthermore, a partition that does not reach the top is provided in the middle of the water collection pool to divide the water collection pool into two parts, one of which is used to collect the water input from the water outlet of the capture device and let it stand. The supernatant after standing overflows to the other part of the water collection pool and finally flows out through the water outlet of the water collection pool at the lower end of this part.

[0007] Furthermore, a supporting layer is provided at the bottom of the sulfur autotrophic reactor, and a sulfur filler is provided on the supporting layer; a reactor water inlet is provided at the bottom of the sulfur autotrophic reactor, and a reactor water outlet is provided at the top.

[0008] Furthermore, a partition reaching the top is provided in the middle of the sedimentation tank to divide the sedimentation tank into sedimentation tank A and sedimentation tank B. Sedimentation tanks A and B are open, and agitators and water outlets are provided on the top. Solid-liquid separators are provided in the upper middle position inside, and sedimentation tank slag discharge ports are provided at the bottom.

[0009] The present invention also provides a method for treating wastewater by an integrated device based on the above-mentioned basic calcite to capture carbon dioxide to enhance sulfur autotrophic denitrification and coordinate phosphorus, fluorine and sulfur removal, the method comprising:

[0010] (1) Pumping wastewater from the water inlet of the capture device into the CO2 capture device, then adding basic calcite particles and stirring, while introducing CO2 through the CO2 gas pipe inlet for aeration, the treated wastewater is discharged through the water outlet of the capture device, and the basic calcite particle precipitation is discharged through the waste residue discharge port and collected;

[0011] (2) The wastewater discharged from the water outlet of the capture device enters the water collection tank for standing, and the supernatant after standing is discharged from the water outlet of the water collection tank;

[0012] (3) the wastewater output from the water outlet of the water collection tank enters the sulfur autotrophic reactor through the water inlet of the reactor, undergoes sulfur autotrophic reaction treatment, and then is output through the water outlet of the reactor;

[0013] (4) the wastewater input from the reactor outlet is passed into a sedimentation tank A, and the basic calcite particles collected in step (1) are added, stirred, and then discharged from the outlet of the sedimentation tank A after reaction to obtain effluent that meets the treatment standards;

[0014] (5) Adding wastewater and the basic calcite granular precipitate collected in step (1) into sedimentation tank B, stirring and reacting the wastewater, and discharging the precipitate from the outlet of sedimentation tank B to obtain effluent meeting the treatment standard.

[0015] Furthermore, the wastewater in step (1) is nitrogen-containing wastewater; the nitrate nitrogen concentration in the nitrogen-containing wastewater is 0 to 50 mg / L.

[0016] Furthermore, the concentration of nitrate nitrogen in the nitrogen-containing wastewater is 0 to 30 mg / L.

[0017] Furthermore, the basic calcite particles in step (1) are obtained by crushing and screening the waste residue produced by causticization during the alkali recovery process; the calcium carbonate content in the basic calcite particles is 80-90wt%.

[0018] Furthermore, in step (1), the feed rate of basic calcite particles is 1 to 5 g / h.

[0019] Furthermore, in step (1), the feed rate of basic calcite particles is 1 to 3 g / h.

[0020] Furthermore, the hydraulic retention time (HRT) of the wastewater in step (1) is 15 to 24 hours.

[0021] Furthermore, the hydraulic retention time (HRT) of the wastewater in step (1) is 17 to 20 hours.

[0022] Furthermore, in step (1), the carbon dioxide ventilation flow rate is 0.1 to 0.5 L / h.

[0023] Furthermore, in step (1), the carbon dioxide ventilation flow rate is 0.3 to 0.5 L / h.

[0024] Furthermore, the treatment temperature in step (1) is 20-25° C. and the pH is 6-7.

[0025] Specifically, the treatment temperature in step (1) is 25° C. and the pH is 6.8.

[0026] Furthermore, in step (3), the filling volume of the sulfur filler accounts for 50 to 90% of the total volume of the sulfur autotrophic reactor.

[0027] Furthermore, in step (3), the filling volume of the sulfur filler accounts for 60-80% of the total volume of the sulfur autotrophic reactor.

[0028] Furthermore, in step (3), the HRT is 1 to 5 h.

[0029] Furthermore, in step (3), the HRT is 2 to 4 hours.

[0030] Furthermore, the concentration of the basic calcite particles precipitated in step (4) is 10 to 15 g / L.

[0031] Preferably, the concentration of the basic calcite particles precipitated in step (4) is 11 to 13 g / L.

[0032] Specifically, the concentration of the basic calcite particle precipitation in step (4) is 12 g / L.

[0033] Furthermore, the reaction time in step (4) is 4 to 10 days.

[0034] Furthermore, the reaction time in step (4) is 5 to 6 days.

[0035] Furthermore, the wastewater in step (5) is wastewater containing fluorine and / or phosphorus; the fluorine content in the wastewater containing fluorine and / or phosphorus is 0 to 20 mg / L, and the phosphorus content is 0 to 20 mg / L.

[0036] Furthermore, the fluorine content in the fluorine and / or phosphorus-containing wastewater is 0 to 15 mg / L, and the phosphorus content is 0 to 15 mg / L.

[0037] Furthermore, in step (5), the concentration of the basic calcite particle precipitation is 10 to 15 g / L.

[0038] Preferably, the concentration of the basic calcite particles precipitated in step (4) is 11 to 13 g / L.

[0039] Specifically, the concentration of the basic calcite particle precipitation in step (5) is 12 g / L.

[0040] Furthermore, the reaction time in step (5) is 4 to 10 days.

[0041] Furthermore, the reaction time in step (5) is 5 to 6 days.

[0042] Beneficial Effects

[0043] The present invention designs an integrated device for enhancing sulfur autotrophic denitrification and coordinated phosphorus, fluorine and sulfur removal based on capturing carbon dioxide with basic calcite. The device can be used in conjunction with basic calcite to achieve efficient denitrification, phosphorus, fluorine and sulfur removal from wastewater, successfully expanding the application range of basic calcite. At the same time, the efficient treatment performance of basic calcite is also discovered, opening up an economical and efficient treatment method for sulfur autotrophic denitrification technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1It is a schematic diagram of an integrated device based on capturing carbon dioxide with basic calcite to enhance sulfur autotrophic denitrification and coordinated removal of phosphorus, fluorine and sulfur; wherein 1. water inlet of the capture device; 2. water outlet of the capture device; 3. CO2 gas pipe inlet; 4. waste residue discharge port; 5. feed port; 6. agitator; 7. solid-liquid separator; 8. aeration device; 9. CO2 capture material; 10. water outlet of the collection tank; 11. water inlet of the reactor; 12. water outlet of the reactor; 13. sulfur filler; 14. supporting layer; 15. water outlet of sedimentation tank A; 16. slag discharge port of sedimentation tank; 17. water outlet of sedimentation tank B.

[0045] Figure 2 This is a graph showing the relationship between nitrate nitrogen concentration and time.

[0046] Specific implementation part

[0047] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0048] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "attachment" and "placement" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or both forming an integral body; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0049] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0050] The present invention provides an integrated device for enhancing sulfur autotrophic denitrification and coordinated removal of phosphorus, fluorine and sulfur based on capturing carbon dioxide with basic calcite. The device is composed of a CO2 capture device, a water collection tank, a sulfur autotrophic reactor and a sedimentation tank connected in sequence.

[0051] The CO2 capture device is a cylinder, with a capture device water inlet 1 provided at the bottom of the column for inputting wastewater, and a capture device water outlet 2 provided at the top of the column for inputting the outlet water into a water collection tank; a CO2 air pipe inlet 3 is provided at the bottom of the capture device, CO2 is input through this inlet, and the CO2 capture device is aerated through an aeration device 8; a waste residue discharge port 4 is also provided at the bottom of the capture device for discharging the precipitate and residue in the CO2 capture device, and the precipitate and residue can be subsequently passed into sedimentation tank A and sedimentation tank B; a feed port 5 and an agitator 6 are provided at the top of the capture device, and basic calcite is input into the CO2 capture device through the feed port 5; a solid-liquid separator 7 is provided at the upper middle position inside the capture device.

[0052] A partition that does not reach the top is provided in the middle of the water collection tank to divide the water collection tank into two parts, one of which is used to collect the water input from the water outlet 2 of the capture device and let it stand. The supernatant after standing will overflow to the other part of the water collection tank, and finally output to the sulfur autotrophic reactor through the water outlet 10 of the water collection tank at the lower end of this part.

[0053] A supporting layer 14 is provided at the bottom of the sulfur autotrophic reactor, and a sulfur filler 13 is provided on the supporting layer 14. The supernatant of the water collection tank is injected into the sulfur autotrophic reactor through a reactor water inlet 11 at the bottom of the sulfur autotrophic reactor, and finally input into a sedimentation tank A at a reactor water outlet 12 above the sulfur autotrophic reactor.

[0054] The sedimentation tank is divided into sedimentation tank A and sedimentation tank B. The two sedimentation tanks are separated by a partition and both have openings on the top. The precipitate and residue of the CO2 capture device are input into the sedimentation tank through the opening on the top. The effluent of the sulfur autotrophic reactor is input into the sedimentation tank A through the reactor outlet 12, and is output through the A sedimentation tank outlet 15 at the upper end of the sedimentation tank A after being treated; the fluoride and phosphate wastewater is input into the sedimentation tank B from the top, and the wastewater is output through the B sedimentation tank outlet 17 at the upper end of the sedimentation tank B after being treated; the agitator 6 is provided on the top of the sedimentation tank A and the sedimentation tank B, and a solid-liquid separator 7 is also provided at the upper middle position of the interior, and a sedimentation tank slag discharge port 16 is provided at the bottom.

[0055] Example 1 Screening of basic calcite

[0056] Basic calcite is taken from a papermaking industrial park in Guangxi. It is the waste residue produced by causticization during the alkali recovery process. The basic calcite particles are off-white, with an average calcium carbonate content of 85wt%, a particle size of 5mm-20mm, and are relatively loose overall. The basic calcite is ground and passed through a 10-mesh sieve to obtain basic calcite particles.

[0057] Example 2 Basic Calcite Fixation of CO2

[0058] The designed simulated wastewater contains the following components: nitrate nitrogen concentration of 20 mg / L, and trace elements required by sulfur autotrophic denitrifying bacteria (specifically: CaCl2·2H2O is 4.8 mg / L; MgSO4·7H2O is 5.4 mg / L; FeCl2·4H2O is 1.2 mg / L; CoCl2·6H2O is 1.2 mg / L; MnCl2·4H2O is 0.3 mg / L; CuCl2·2H2O is 0.018 mg / L; ZnCl2 is 0.03 mg / L; HBO3 is 0.03 mg / L; (NH4)6Mo7O 24 ·4H2O is 0.054mg / L; Na2SeO3 is 0.04mg / L; NiCl2·6H2O is 0.03mg / L; EDTA is 0.6mg / L; HCl 36% is 0.0006mg / L).

[0059] The above simulated wastewater is introduced from the water inlet 1 of the capture device by a peristaltic pump. The sieved basic calcite particles are fed through the feed port 5 with a screw feeder. After the basic calcite particles enter the CO2 capture device, they are slowly stirred by the agitator 6 and fully contacted with water. Then the carbon dioxide cylinder is opened, and the carbon dioxide is overflowed in the form of small bubbles by the aeration device 8, which fully contact and react with the basic calcite particles. The basic calcite particles that have not reacted completely will sink into the lower sedimentation area and can be discharged from the waste residue discharge port 4, and subsequently used as feed for the sedimentation tank. Smaller basic calcite particles may float, and the installed solid-liquid separator 7 can separate and settle the floating basic calcite particles. The effluent from the CO2 capture device enters the water collection tank from the water outlet 2 of the capture device, settles again in the left pool of the water collection tank, overflows to the right pool of the water collection tank, and flows out from the water outlet 10 of the water collection tank. The water is connected to the reactor water inlet 11 by a peristaltic pump to supply water to the sulfur autotrophic reactor.

[0060] The CO2 capture device is a cylinder with a diameter of 30 cm and a height of 60 cm. The effective volume of the entire capture device is 42.4 L, and the water inlet HRT is 18.8 h. The basic calcite particle feed rate is 1.1 g / h. The carbon dioxide ventilation flow rate is 0.3 L / h. The treatment temperature is 25 ° C and the pH is 6.8.

[0061] The water collection tank is a cube with the dimensions of 30 cm × 15 cm × 60 cm, which is divided into a left water collection tank and a right water collection tank overflowing to the right. The water collection tank HRT = 11.5h.

[0062] Example 3 Sulfur autotrophic enhanced denitrification

[0063] Water is introduced from the reactor water inlet 11 by a peristaltic pump, and the HRT is 2h. After passing through the support layer 14 and the sulfur filler 13, the water is discharged through the reactor water outlet 12. Water samples are taken out at 0.5d, 1d, 2d, 5d, 7d, 10d, and 15d to measure the nitrate nitrogen data. After 2d, the nitrate nitrogen content is 5mg / L, and after 7d, the nitrate nitrogen content is below 1mg / L. The denitrification efficiency is 95%. The specific results are shown in Figure 2 .

[0064] The sulfur autotrophic reactor is a cylinder with a diameter of 10 cm and a height of 60 cm. The reactor is filled with sulfur filler with a particle size of 3 to 4 mm, and the filling volume accounts for 70% of the reactor volume.

[0065] Example 4 Removal of SO4 by Basic Calcite 2-

[0066] The effluent from the sulfur autotrophic reactor enters the sedimentation tank A, and the basic calcite residue discharged from the CO2 capture device is fed by a screw feeder, and the agitator 6 is slowly stirred and mixed to uniformly control the concentration of the basic calcite residue to 12g / L, and then the water is discharged from the outlet 15 of the sedimentation tank A. Water samples are taken at 0.5d, 1d, 2d, 5d, 7d, 10d, and 15d to determine SO4 2- Data. SO4 after 2d 2- The removal rate reached 45%, and after 5 days, SO4 2- The removal rate reaches about 70%.

[0067] Section A of the sedimentation tank is a cylinder with a diameter of 15 cm and a height of 60 cm.

[0068] Example 5 Basic Calcite Removal F - PO4 3-

[0069] In sedimentation tank B, simulated wastewater is introduced, where F - Concentration is 10mg / L, PO4 3- The concentration is 10 mg / L. The basic calcite residue discharged from the CO2 capture device is fed with a screw feeder and stirred and mixed evenly by a stirrer 6 at a slow speed. The concentration of the basic calcite residue is controlled to be 12 g / L, and then the water is discharged from the outlet 17 of the B sedimentation tank. Water samples are taken at 0.5d, 1d, 2d, 5d, 7d, 10d, and 15d to determine F - PO4 3- Data. 2d after F - The removal rate reaches 60%, PO4 3- The removal rate reached 83%, and after 5 days, F - The removal rate reaches 92%, PO4 3- The removal rate reaches 98%.

[0070] Section B of the sedimentation tank is a cylinder with a diameter of 30 cm and a height of 60 cm.

[0071] Comparative Example 1

[0072] In order to investigate the effect of different materials on the denitrification of the sulfur autotrophic reactor by providing inorganic carbon sources and alkalinity and to investigate its cost, denitrification efficiency, and the number of days to reach the maximum denitrification efficiency, limestone (mainly composed of calcium carbonate, 90wt%), potassium carbonate, ammonium bicarbonate, and magnesium carbonate were taken respectively, and only the basic calcite particles were replaced with the above materials respectively, wherein the carbonate content of each material was kept the same, the mass was calculated and each material was weighed, and the other conditions were kept consistent with those in Examples 2 and 3. The final results are shown in Table 1, and it can be seen that basic calcite is not only extremely low in cost but also has a high denitrification efficiency of up to 95%, and is a cheap and efficient inorganic carbon source.

[0073] Table 1

[0074] Material cost Denitrification efficiency Days to reach maximum denitrification efficiency Basic Calcite Very low 95％ 3d limestone middle 95％ 4d Potassium carbonate high 82％ 4d Magnesium carbonate high 73％ 5d Ammonium bicarbonate high 88％ 3d

[0075] Comparative Example 2

[0076] In order to investigate the effect of different temperatures on the capture of carbon dioxide by basic calcite, a heating insulation sleeve was used to wrap the outside of the CO2 capture device, and experiments were carried out for five days at 10°C, 15°C and 25°C, respectively. The other conditions were kept consistent with those in Example 2. On the fifth day, the effluent from the sulfur autotrophic reactor was taken, and the most suitable temperature was compared by comparing the sulfur autotrophic denitrification efficiency and the sulfur autotrophic denitrification effluent pH. The final results are shown in Table 2. It can be seen that at 25°C, the capture of carbon dioxide by basic calcite is the most effective.

[0077] Table 2

[0078] temperature Denitrification efficiency pH 10℃ 75％ 5.7 15℃ 88％ 6.2 25℃ 96％ 6.8

[0079] Comparative Example 3

[0080] In order to investigate the removal of SO4 by basic calcite residue 2- The optimal concentration of the basic calcite residue was set to 2g / L, 4g / L, 8g / L, 12g / L, and 16g / L, respectively. The other conditions were kept the same as those in Example 4. A five-day experiment was conducted, and samples were taken on the second and fifth days to determine SO4 2- The final results are shown in Table 3. It can be seen that when the concentration of basic calcite is 12g / L, the effect on SO4 2- The removal effect was the best. On the fifth day, SO4 2- The removal rate reaches 70%.

[0081] Table 3

[0082] concentration <![CDATA[SO4 2- Removal rate (2d)]]> <![CDATA[SO4 2- Removal rate (5d)]]> 2g / L 2％ 4％ 4g / L 5％ 16％ 8g / L 27％ 42％ 12g / L 45％ 70％ 16g / L 32％ 58％

[0083] Comparative Example 4

[0084] In order to investigate the removal of PO4 by basic calcite residue 3- The optimal concentration of the basic calcite residue was set to 2g / L, 4g / L, 8g / L, 12g / L, and 16g / L, respectively. The other conditions were kept the same as those in Example 5. A five-day experiment was conducted, and samples were taken on the second and fifth days to determine PO4 3- The final results are shown in Table 4. It can be seen that when the concentration of basic calcite residue is 12g / L, the effect on PO4 3- The removal effect was the best. On the fifth day, PO4 3- The removal rate reaches 98%.

[0085] Table 4

[0086]

[0087]

[0088] Comparative Example 5

[0089] In order to investigate the removal of F - The optimal concentration of the basic calcite residue was set to 2 g / L, 4 g / L, 8 g / L, 12 g / L, and 16 g / L, respectively. The other conditions were kept the same as those in Example 5. A five-day experiment was conducted, and samples were taken on the second and fifth days to determine the F - The final results are shown in Table 5. It can be seen that when the concentration of basic calcite residue is 12g / L, the - The removal effect is the best, on the fifth day F - The removal rate reached 92%.

[0090] Table 5

[0091] concentration <![CDATA[F - Removal rate (2d)]]> <![CDATA[F - Removal rate (5d)]]> 2g / L 11％ 28％ 4g / L 30％ 43％ 8g / L 44％ 68％ 12g / L 60％ 92％ 16g / L 52％ 89％

[0092] The embodiments provided above are not intended to limit the scope of the present invention, and the steps described are not intended to limit the execution order thereof. Those skilled in the art may make obvious improvements to the present invention in combination with existing common knowledge, which also fall within the scope of protection defined by the claims of the present invention.

Claims

1. An integrated device for enhancing sulfur autotrophic denitrification and coordinated removal of phosphorus, fluorine and sulfur based on capturing carbon dioxide with basic calcite, characterized in that: The device is composed of a CO2 capture device, a water collection tank, a sulfur autotrophic reactor and a sedimentation tank connected in sequence; The CO2 capture device is columnar, with a water inlet for the capture device provided below the column body and a water outlet for the capture device provided above the column body; a CO2 gas pipe inlet and a waste residue discharge port are provided at the bottom of the CO2 capture device, and the CO2 gas pipe inlet is connected to the aeration device inside the CO2 capture device; a feed port and a stirrer are provided at the top of the CO2 capture device; a solid-liquid separator is provided at the upper middle position inside the CO2 capture device; A partition that does not reach the top is provided in the middle of the water collection tank to divide the water collection tank into two parts, one of which is used to collect the water input from the water outlet of the capture device and let it stand, and the supernatant after standing overflows to the other part of the water collection tank, and finally flows out through the water outlet of the water collection tank at the lower end of the part; The sulfur autotrophic reactor has a supporting layer at the bottom, and a sulfur filler is arranged on the supporting layer; a reactor water inlet is arranged at the bottom, and a reactor water outlet is arranged at the top; A partition reaching the top is arranged in the middle of the sedimentation tank to divide the sedimentation tank into sedimentation tank A and sedimentation tank B. Sedimentation tanks A and B are open, and agitators and water outlets are arranged on the top. Solid-liquid separators are arranged in the upper middle position inside, and sedimentation tank slag discharge ports are arranged at the bottom.

2. A method for treating wastewater based on the integrated device described in claim 1, characterized in that: The method comprises: (1) Pumping wastewater from the water inlet of the capture device into the CO2 capture device, then adding basic calcite particles and stirring, while introducing CO2 through the CO2 gas pipe inlet for aeration, the treated wastewater is discharged through the water outlet of the capture device, and the basic calcite particle precipitation is discharged through the waste residue discharge port and collected; (2) The wastewater discharged from the water outlet of the capture device enters the water collection tank for standing, and the supernatant after standing is discharged from the water outlet of the water collection tank; (3) the wastewater output from the water outlet of the water collection tank enters the sulfur autotrophic reactor through the water inlet of the reactor, undergoes sulfur autotrophic reaction treatment, and then is output through the water outlet of the reactor; (4) the wastewater input from the outlet of the reactor is passed into a sedimentation tank A, and the basic calcite precipitate collected in step (1) is added, the concentration of the basic calcite precipitate is 10-15 g / L, and after stirring and reacting, the wastewater is discharged from the outlet of the sedimentation tank A to obtain effluent that meets the treatment standards; (5) Adding wastewater and the basic calcite precipitate collected in step (1) into sedimentation tank B, wherein the concentration of the basic calcite precipitate is 10 to 15 g / L, stirring and reacting, and then discharging the mixture from the outlet of sedimentation tank B to obtain effluent that meets the treatment standards.

3. The method according to claim 2, characterized in that The wastewater in step (1) is nitrogen-containing wastewater; the nitrate nitrogen concentration in the nitrogen-containing wastewater is 0 to 50 mg / L.

4. The method according to claim 2, characterized in that In step (1), the basic calcite particles are obtained by crushing and screening the waste residue produced by causticization during the alkali recovery process; the calcium carbonate content in the basic calcite particles is 80-90wt%; and the feeding rate of the basic calcite particles is 1-5g / h.

5. The method according to claim 2, characterized in that The hydraulic retention time (HRT) of the wastewater in step (1) is 15 to 24 hours.

6. The method according to claim 2, characterized in that In step (1), the carbon dioxide ventilation flow rate is 0.1-0.5 L / h; the treatment temperature is 20-25° C., and the pH is 6-7.

7. The method according to claim 2, characterized in that In step (3), the filling volume of the sulfur filler accounts for 50-90% of the total volume of the sulfur autotrophic reactor; and the HRT is 1-5h.

8. The method according to claim 2, characterized in that The concentration of the basic calcite particle precipitation in step (4) is 11-13 g / L; and the reaction time is 4-10 days.

9. The method according to claim 2, characterized in that The wastewater in step (5) is wastewater containing fluorine and / or phosphorus; the fluorine content in the wastewater containing fluorine and / or phosphorus is 0 to 20 mg / L, and the phosphorus content is 0 to 20 mg / L.

10. The method according to claim 2, characterized in that In step (5), the concentration of the basic calcite particle precipitation is 11 to 13 g / L; and the reaction time is 4 to 10 days.

Images