CN211936253U

CN211936253U - System for multistage desulfurization pregnant solution cavitation desorption sulfur dioxide

Info

Publication number: CN211936253U
Application number: CN202020378780.4U
Authority: CN
Inventors: 温高; 温日辉
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-03-23
Filing date: 2020-03-23
Publication date: 2020-11-17
Anticipated expiration: 2030-03-23

Abstract

The utility model discloses a system for multi-stage desulfurization pregnant solution cavitation desorption sulfur dioxide, which comprises a multi-stage cavitation desorption unit, wherein each stage cavitation desorption unit is divided into an upper chamber and a lower chamber by a heating surface, the upper chamber is a cavitation desorption chamber, and the lower chamber is a steam heating chamber; the air outlet of the cavitation desorption chamber of each front stage cavitation desorption unit is connected to the steam inlet of the steam heating chamber of the next stage cavitation desorption unit, and the condensed water outlet of the steam heating chamber of each back stage cavitation desorption unit is connected to the desorption chamber of the cavitation desorption unit of the previous stage cavitation desorption unitAnd (6) liquid inlet. The method for desorbing sulfur dioxide by multi-stage desulfurization pregnant solution cavitation comprises a multi-stage cavitation desorption unit, wherein the SO in the stage of cavitation desorption chamber is cavitated and desorbed by using steam generated during cavitation in the cavitation desorption chamber of the previous stage cavitation desorption unit as heating steam in the steam heating chamber of the next stage cavitation desorption unit₂The heat energy of the desorption steam of the previous stage becomes a heat source of the cavitation desorption of the next stage.

Description

System for multistage desulfurization pregnant solution cavitation desorption sulfur dioxide

Technical Field

The utility model belongs to the field of energy and power engineering and environmental engineering, concretely relates to system of multistage desulfurization pregnant solution cavitation desorption sulfur dioxide.

Background

Currently, sulfur co-produced with coal is combusted to produce SO₂Causes air pollution, is one of factors for forming acid rain and haze weather, and is a country poor in available sulfur resources. Therefore, the SO in the coal-fired flue gas is efficiently removed and recycled₂The advanced method of (2) has been the subject of research and exploration.

The basic aluminium sulfate desorption desulfurization method is theoretically one of SO removal and desorption₂High efficiency, desorption of SO from the desulfurized rich solution₂The post-regenerated basic aluminum sulfate is recycled, and the desorption product-high-purity SO₂Can be used as a product or for manufacturing sulfuric acid and sulfur for sale, and has double values of sulfur dioxide pollution treatment and coal sulfur resource reclamation.

The prior art discloses the removal of SO from alkaline aluminium sulphate solutions₂The desulfurization rich solution desorbs SO₂There are two main methods available: one is to steam the desulfurized rich solution by water vapor to strip SO at the temperature of 100 DEG C₂The experiments of Shenyang chemical research institute in 1954 show that 1 ton of SO is desorbed when the desorption rate is close to 100%₂6.7 tons of low-pressure steam is consumed; secondly, the basic aluminum sulfate desulfurization pregnant solution cavitation desorption SO disclosed in the patents (ZL201821778513.5 and CN201811276655.6)₂The method, the applicant's experiment shows that when the desorption rate is close to 94%, 1 ton of SO is desorbed by cavitation under the condition of 55 DEG C₂About 6.7 tons of water vapor is generated (the heat consumption is about 15.856 multiplied by 10)⁶Kilojoule), the heat source is needed to provide huge heat, the heat consumption is high, and the investment of conveying equipment is large; per desorption 1 ton SO₂At least 6.7 tons of steam are accompanied and mixed to form mixed gas, and 6.7 tons of steam are condensed to obtain 1 ton of SO₂The gas and condensation equipment is large in scale and high in investment. Desorption of SO₂The cost is increased, which is one of the reasons that the alkaline aluminum sulfate desorption desulfurization method cannot be popularized and applied.

In view of this, the present invention is especially provided.

SUMMERY OF THE UTILITY MODEL

To the above problem, the utility model aims at providing a system of multistage desulfurization pregnant solution cavitation desorption sulfur dioxide solves alkaline aluminum sulfate desorption desulfurization method desorption SO₂High heat consumption, large scale of heat energy conveying equipment and water vapor condensing equipment and high investment.

In order to achieve the purpose, the utility model provides a system for desorbing sulfur dioxide by multi-stage desulfurization pregnant solution cavitation, which comprises a multi-stage cavitation desorption unit, wherein each stage of cavitation desorption unit is divided into an upper chamber and a lower chamber by a heating surface, the upper chamber is a cavitation desorption chamber, and the lower chamber is a steam heating chamber;

the air outlet of the cavitation desorption chamber of each front stage cavitation desorption unit is connected to the steam inlet of the steam heating chamber of the back stage cavitation desorption unit through a pipeline.

Preferably, the condensed water outlet of the steam heating chamber of each rear-stage cavitation desorption unit is connected to the desorption liquid inlet of the cavitation desorption chamber of the previous-stage cavitation desorption unit through a pipeline, and the gas outlets of the steam heating chambers from the second-stage cavitation desorption unit to the last-stage cavitation desorption unit are connected to the SO through a vacuum pumping system₂By utilizing the process flow, a gas outlet of a steam heating chamber of the primary cavitation desorption unit is provided with a vacuum pumping system, and a condensed water outlet of the steam heating chamber of the primary cavitation desorption unit is connected to a heat source heat regeneration system through a condensed water pump.

Further, a steam inlet of a steam heating chamber of the first-stage cavitation desorption unit is connected with a steam jet pump and a bypass valve which are connected in parallel, and steam enters the steam heating chamber through the steam jet pump or the bypass valve.

Further, an exhaust port of a cavitation desorption chamber of the last stage cavitation desorption unit is connected with a heat exchanger and a direct air cooling system, an air side inlet of the heat exchanger is connected with the exhaust port of the cavitation desorption chamber of the last stage cavitation desorption unit, and an air side outlet of the heat exchanger is connected with the direct air cooling system.

Further, the system also comprises a desulfurization rich liquid header and a regeneration liquid header, wherein the desulfurization rich liquid header conveys the desulfurization rich liquid to the cavitation desorption chamber of each stage of cavitation desorption unit, and the cavitation desorption chamber of each stage of cavitation desorption unit desorbs SO₂Outputting the regenerated solution to the regenerated solution header; the water side inlet of the heat exchanger is connected with a desulfurization system, the water side outlet of the heat exchanger is connected with the desulfurization rich liquid header, the heat exchanger and the condensed water outlet of the direct air cooling system are connected with the desulfurization rich liquid header, and the vacuumizing system of the direct air cooling system is connected with SO₂Utilizing the process flow.

Preferably, the cavitation temperature of the desulfurization rich liquid of the former stage cavitation desorption unit is higher than that of the desulfurization rich liquid of the latter stage cavitation desorption unit, and the steam temperature of the steam heating chamber of the same stage cavitation desorption unit is higher than that of the desulfurization rich liquid of the cavitation desorption chamber.

The utility model provides a pair of rich liquid cavitation desorption sulfur dioxide's of multistage desulfurization system has following beneficial effect:

1. the industrial production exhaust steam contains a large amount of latent heat of vaporization and is discharged to the natural environment as waste heat; the utility model uses the waste heat to desorb SO for cavitation₂Provides heat, not only solves the problem of SO desorption by cavitation₂The needed huge vaporization heat also enables the latent heat of the dead steam to be reused once, SO as to treat waste with waste and reduce SO₂The cost of desorption;

2. the condensed water heated in the steam heating chamber is not polluted and can be sent back to the heat source regenerative system for reuse;

3. SO generated by desorption of the previous stage cavitation desorption unit₂The mixed gas with the water vapor enters a steam heating chamber of the subsequent stage cavitation desorption unit to provide heat required by the subsequent stage cavitation desorption unit, the latent heat of vaporization is repeatedly utilized for many times, the heat provided by the required heat source is obviously reduced, and compared with the heat provided by the single-stage cavitation desorption unit, the N-stage cavitation desorption unit is about 1/N of the single-stage cavitation desorption unit;

4. compared with a single stage, the steam condensation amount of a direct air cooling system of a last stage cavitation desorption unit in the N-stage cavitation desorption unit is less than 1/N of the single stage, so that the steam condensation amount of the direct air cooling system is obviously reduced;

5. the temperature of the circulating desulfurization liquid of the desulfurization system is lower than that of steam and SO generated by the last stage cavitation desorption unit₂The temperature of the mixed gas and the heat exchanger utilize the temperature difference to obtain the beneficial effects of not only improving the temperature of the desulfurization rich liquid entering the cavitation desorption chamber, but also reducing the condensation load of the direct air cooling system, and the design of the multi-stage cavitation desorption unit can obviously reduce the steam condensation load of the direct air cooling system;

6. the scale of equipment and a direct air cooling system which are provided with heat by a heat source is obviously reduced, and the desorption SO is effectively reduced₂Investment of equipment, final SO₂The desorption cost is obviously reduced.

Drawings

Fig. 1 is a schematic structural diagram of a system for 3-stage desulfurization pregnant solution cavitation desorption of sulfur dioxide in examples 1 and 2.

In the drawings: 1. a heated surface; 2. a cavitation desorption chamber; 3. a steam heating chamber; 4. a steam inlet; 5. a condensed water outlet; 6. a gas outlet; 7. a vacuum pumping system; 8. a desorption liquid inlet; 9. a desorption liquid outlet; 10. an exhaust port; 11. a steam jet pump; 12. a bypass valve; 13. a heat exchanger; 14. a direct air cooling system; 15. a desulfurization rich liquor header; 16. a throttle valve; 17. a regenerated liquid header; 18. a regenerative liquid pump; 19. a condensate pump; 20. a desulfurization system.

Detailed Description

In order to make the technical field better understand the solution of the present invention, the present invention will be further described in detail with reference to the following embodiments.

The patent discloses a system for multistage desulfurization pregnant solution cavitation desorption sulfur dioxide, for the pregnant solution cavitation desorption SO of alkaline aluminum sulfate desulfurization₂The system for desorbing sulfur dioxide by N-stage desulfurization pregnant solution cavitation comprises a first-stage cavitation desorption unit, a last-stage cavitation desorption unit and N-2 intermediate-stage cavitation desorption units, and water vapor is continuously used for multiple timesThe latent heat is released by condensation, and the problem of SO desorption of the desulfurization rich liquid of the alkaline aluminum sulfate by cavitation₂High heat consumption, large scale of heat energy conveying equipment and water vapor condensing equipment, high investment and the like, and effectively reduces SO₂And (4) desorption cost.

Each stage of cavitation desorption unit is divided into an upper chamber and a lower chamber by a heating surface 1, the upper chamber is a cavitation desorption chamber 2, the lower chamber is a steam heating chamber 3, the first stage cavitation desorption unit taking industrial production exhaust steam as a heat source and the steam heating chambers 3 of the remaining cavitation desorption units are all positioned at the lower part of the heating surface 1, the steam heating chamber 3 is provided with a steam inlet 4, the lower part of the steam heating chamber 3 is provided with a condensed water outlet 5, and the upper part of the steam heating chamber 3 is provided with a gas outlet 6 and a vacuum pumping system 7; the cavitation desorption chambers 2 of all stages of cavitation desorption units are positioned at the upper part of the heated surface 1, the cavitation desorption chambers 2 are provided with desorption liquid inlets 8, the lower parts of the cavitation desorption chambers 2 are provided with desorption liquid outlets 9, and the upper parts of the cavitation desorption chambers 2 are provided with exhaust ports 10.

The heated surface 1 is used for transferring heat released by condensation of water vapor in the vapor heating chamber 3 to desorbed liquid in the cavitation desorption chamber 2; the upper surface of the heating surface 1 is the bottom of the cavitation desorption chamber 2, the cavitation temperature of the basic aluminum sulfate desulfurization rich liquid in the cavitation desorption chamber 2 of the final stage cavitation desorption unit is at least higher than 50 ℃, and the cavitation temperature of the previous stage cavitation desorption unit is required to be higher than that of the next stage, so that necessary heat transfer temperature difference is formed; the lower surface of the heating surface 1 is the top of the steam heating chamber 3, and the steam temperature in the steam heating chamber 3 is higher than the cavitation temperature set by the desorption desulfurization rich liquid in the cavitation desorption chamber 2 of the current stage, so that necessary heat transfer temperature difference is formed.

The steam inlet 4 of the steam heating chamber of the primary cavitation desorption unit taking industrial production exhaust steam as a heat source is connected with a steam jet pump 11 and a bypass valve 12 which are connected in parallel, the industrial production exhaust steam enters the steam inlet 4 through the steam jet pump 11 or the bypass valve 12, the steam jet pump 11 is used for heating the steam turbine exhaust steam with the temperature lower than the required temperature to the required temperature by high-pressure steam and outputting the steam to the steam heating chamber 3 of the primary cavitation desorption unit, if the steam turbine exhaust steam temperature meets the required temperature range or the steam extraction meeting the required temperature range exists, the steam can be directly conveyed through the bypass valve 12 and the steam inlet 4Sending the mixture to a steam heating chamber 3 of a primary cavitation desorption unit; the condensed water outlet 5 of the first-stage cavitation desorption unit is also connected with a condensed water pump 19. An exhaust port 10 of the cavitation desorption chamber of the final stage cavitation desorption unit is sequentially connected with a heat exchanger 13 and a direct air cooling system 14, wherein the positions of the heat exchanger 13 and the direct air cooling system 14 are higher than a desulfurization rich liquid header 15. The water side of the heat exchanger 13 is used for receiving the desulfurized rich liquid with lower temperature from the desulfurization system 20, and the gas side of the heat exchanger 13 is used for receiving the water vapor and SO output by the cavitation desorption chamber exhaust port 10 of the final stage cavitation desorption unit₂The mixed gas and the mixed gas are subjected to surface heat exchange, the heated desulfurization rich solution and the condensed water are output to a desulfurization rich solution header 15, and uncondensed water vapor and SO are mixed₂The mixed gas is output to the direct air cooling system 14. The direct air cooling system 14 comprises a steam distribution system, a radiator, a condensed water system and a vacuum pumping system; the direct air cooling system 14 is used for receiving water vapor and SO from the heat exchanger₂Mixing the gases and condensing the water vapour and SO by surface heat exchange with ambient air₂Separating, and vacuumizing to remove SO₂Output to SO₂The process flow is utilized, and the condensed water is collected in a condensed water system and then is output to the desulfurization rich liquid header 15.

Except for the first-stage cavitation desorption unit, the condensed water outlet 5 of the steam heating chamber 3 of each stage of cavitation desorption unit is higher than the desorption liquid inlet 8 of the previous-stage cavitation desorption chamber 2. The steam heating chamber 3 of the first stage cavitation desorption unit receives water steam through the steam inlet 4, such as steam turbine exhaust steam, extraction steam or steam exhaust steam which is heated by the steam jet pump 11 to reach the steam with required steam temperature, and the steam heating chambers 3 of the other stages cavitation desorption unit receive the water steam and SO output from the cavitation desorption chamber 2 of the previous stage through the steam inlet 4₂And (4) mixing the gases. Condensed water in the steam heating chamber 3 of the first-stage cavitation desorption unit is conveyed to the heat source regenerative system by the condensed water pump 19 through the condensed water outlet 5, and condensed water in the steam heating chambers 3 of the remaining cavitation desorption units at all stages automatically flows into the cavitation desorption chamber 2 at the previous stage by gravity through the condensed water outlet 5. The non-condensable gas in the steam heating chamber 3 of the first-stage cavitation desorption unit is evacuated by a vacuum pumping system 7 through a gas outlet 6, and the non-condensable gas is discharged from the vacuum pumping systemSO in steam heating chamber 3 of remaining cavitation desorption units of different stages₂Gas is sent to SO from a vacuum pumping system 7 through a gas outlet 6₂Utilizing the process flow.

The cavitation desorption chambers 2 of each stage of cavitation desorption units receive the liquid to be desorbed from the desulfurization rich liquid header 15 through respective desorption liquid inlets 8, and the flow rate of the liquid to be desorbed is regulated and controlled by a throttle valve 16 arranged on a pipeline of the desorption liquid inlet 8.

Desorbing SO in cavitation desorption chamber 2 of each stage of cavitation desorption unit₂The regenerated alkaline aluminum sulfate solution is output to a regenerated liquid header 17 through respective desorption liquid outlets 9; an overflow weir is arranged at the desorption liquid outlet 9 and is used for controlling the liquid level height in the cavitation desorption chamber 2; the liquid level height of the regenerated liquid header 17 is lower than the weir crest height of the primary desorption liquid outlet 9, the regenerated liquid header 17 and the primary cavitation desorption chamber are communicated to keep the same indoor pressure, and the free outflow of the overflow weir is formed; liquid flowing out of other overflow weirs at all stages is introduced below the liquid level of the regenerated liquid header 17 through a descending pipeline to form submerged outflow, so that air flow channels communicated with cavitation desorption chambers 2 at all stages are blocked, and conditions are provided for controlling different set values of temperature and pressure of cavitation desorption chambers 2 at all stages; and a regenerated liquid pump 18 is arranged on an outlet pipeline of the regenerated liquid header 17 and used for conveying the regenerated alkaline aluminum sulfate solution to a desulfurization system or a sulfate radical neutralization system.

Example 1

Taking a system for carrying out cavitation desorption on sulfur dioxide by using 3-stage desulfurization rich liquid as an example, the cavitation desorption temperature of the basic aluminum sulfate desulfurization rich liquid in the cavitation desorption chamber 2 of the final-stage cavitation desorption unit is set to be 55 ℃, the interstage temperature difference of the cavitation desorption temperatures of the desulfurization rich liquids of the adjacent two-stage cavitation desorption units is set to be 5 ℃, and the cavitation temperature of the same-stage desulfurization rich liquid and the cavitation temperature of steam or steam and SO in the steam heating chamber 3 are set to be equal to each other₂Setting the temperature difference of the mixed gas to be 5 ℃; the exhaust steam of a steam turbine operating at the back pressure of 12.34kPa is used as the supply for supplying cavitation desorption SO₂The heat source of heat, the steam temperature of the steam turbine exhaust steam is about 50 ℃, and the 50 ℃ exhaust steam needs to be heated to 70 ℃ from high-pressure steam by using a steam jet pump 11. The depth of the desorbed liquid in each stage of cavitation desorption chamber 2 is set to 300mm, and the depth of the desorbed liquid is set toThe desorption liquid inlet 8 flowed at a velocity of 0.05m/s toward the desorption liquid outlet 9.

As shown in figure 1, the 3-stage desulfurization pregnant solution cavitation desorption sulfur dioxide system comprises a first-stage cavitation desorption unit, a 2 nd-stage cavitation desorption unit and a last-stage cavitation desorption unit, wherein the last-stage cavitation desorption unit is arranged at the upper part of the previous stage in a three-dimensional manner.

In the steam heating chamber 3 of the first stage cavitation desorption unit, the 2 nd stage cavitation desorption unit and the last stage cavitation desorption unit, the lower part is steam condensed water, and the upper part is water steam or water steam and SO₂The mixed gas of (3); a steam heating chamber 3 of the first-stage cavitation desorption unit receives steam which is heated to 70 ℃ by exhaust steam of a steam turbine at 50 ℃ through a steam jet pump 11 through a steam inlet 4; the steam heating chamber 3 of the 2 nd stage cavitation desorption unit receives 65 ℃ water steam and SO from the first stage cavitation desorption unit through a steam inlet 4₂Mixing the gas; the steam heating chamber 3 of the final stage cavitation desorption unit receives water vapor and SO at 60 ℃ from the 2 nd stage cavitation desorption unit through a steam inlet 4₂And (4) mixing the gases. Condensed water in a steam heating chamber 3 of the first-stage cavitation desorption unit passes through a condensed water outlet 5 and then is conveyed to a heat source regenerative system by a condensed water pump 19; the other cavitation desorption units of each stage output the condensed water to the cavitation desorption chamber 2 of the previous cavitation desorption unit by gravity through the condensed water outlet 5. The non-condensed gas in the steam heating chamber 3 of the first-stage cavitation desorption unit is output to a vacuum pumping system 7 through a gas outlet 6 and is exhausted. SO in steam heating chamber 5 of 2 nd stage cavitation desorption unit and last stage cavitation desorption unit₂The gas is output to a vacuum-pumping system 7 through a gas outlet 6 and sent to SO₂Utilizing the process flow. SO of final stage cavitation desorption unit₂The separation from the water vapor is carried out in the direct air cooling system 14, and the SO obtained after condensing the water vapor₂The gas is sent to SO from the vacuum pumping system of the direct air cooling system 14₂Utilizing the process flow.

The heated surface 1 is used for transferring heat released by condensation of water vapor in the steam heating chamber 3 to desorbed liquid in the cavitation desorption chamber 2. The upper surface of the heating surface 1 is the bottom of the cavitation desorption chamber 2, and the pressure values in the cavitation desorption chambers 2 of the last stage cavitation desorption unit, the 2 nd stage cavitation desorption unit and the first stage cavitation desorption unit are respectively controlled by the vacuum pumping system of the direct air cooling system 14, the last stage and the second stage vacuum pumping system 7, so that the cavitation desorption temperatures of the basic aluminum sulfate desulfurization rich liquid in the cavitation desorption chambers 2 of the last stage cavitation desorption unit, the 2 nd stage cavitation desorption unit and the first stage cavitation desorption unit respectively reach the set temperatures of 55 ℃, 60 ℃ and 65 ℃, and the heat transfer temperature difference of 5 ℃ between adjacent two stages is formed. The lower surface of the heating surface 1 is the top of a steam heating chamber 3, and the steam temperatures in the steam heating chamber 3 of the last stage cavitation desorption unit, the 2 nd stage cavitation desorption unit and the first stage cavitation desorption unit are respectively set to be 60 ℃, 65 ℃ and 70 ℃, and form a heat transfer temperature difference of 5 ℃ with the set cavitation desorption temperature of the desulfurization rich liquid in the same stage cavitation desorption chamber 2. The steam jet pump 11 is used for heating the turbine exhaust steam with the temperature of 50 ℃ to 70 ℃ with high-pressure steam, and outputting the steam to the steam heating chamber 3 of the first-stage cavitation desorption unit, and the bypass valve is closed under the working condition.

The heat exchanger 13 is arranged above the top of the desulfurization rich liquid header 15 and is used for receiving desulfurization rich liquid with the temperature lower than 45 ℃ from the desulfurization system 20 and 55 ℃ water vapor and SO output from the exhaust port 10 of the cavitation desorption chamber 2 of the final stage cavitation desorption unit₂The mixed gas and the mixed gas are subjected to surface heat exchange, and the heated desulfurization rich solution and the condensed water are output to a desulfurization rich solution header 15; mixing uncondensed water vapor and SO₂The mixed gas is output to the direct air cooling system 14.

The method for desorbing sulfur dioxide by cavitation of 3-stage desulfurization pregnant solution comprises the following steps:

(1) sending the desulfurization rich solution into a heat exchanger 13, a desulfurization rich solution header 15, a regeneration solution header 17 and all stages of cavitation desorption chambers 2, so that the cavitation desorption chambers 2 reach a set liquid level value, and the regeneration solution header 17 reaches a set liquid level value 100mm lower than the liquid level of the first stage cavitation desorption chamber 2;

and starting a direct air cooling system 14 of the last stage cavitation desorption unit and a vacuumizing system 7 of the last stage cavitation desorption unit and the 2 nd stage cavitation desorption unit to evacuate the gas in each stage of cavitation desorption chamber 2, the steam heating chamber 3, the heat exchanger 13, the direct air cooling system 14, the desulfurization rich liquid header 15, the regenerated liquid header 17 and the connecting pipeline to the respective required pressure set value of the desulfurization rich liquid cavitation desorption.

And (3) closing the bypass valve 12, opening a vacuumizing system 7 of the steam heating chamber 3 of the primary cavitation desorption unit to exhaust gas in the steam heating chamber 3, and heating the exhaust steam of the steam turbine at 50 ℃ to 70 ℃ by using high-pressure steam through a steam jet pump 11 to be sent into the steam heating chamber 3.

(2) The desulfurization rich liquid entering the cavitation desorption chamber 2 of the first-stage cavitation desorption unit is subjected to cavitation when the temperature is raised to a cavitation desorption temperature value of 65 ℃ set by the cavitation desorption chamber 2 through heat exchange between the heating surface 1 and the steam in the steam heating chamber 3 of the current stage in the process of flowing from the desorption liquid inlet 8 to the desorption liquid outlet 9 at set liquid level and flow rate, SO that SO in the desulfurization rich liquid is subjected to cavitation₂Desorbing, regenerating the basic aluminum sulfate, wherein the regenerated basic aluminum sulfate solution enters a regenerated liquid header 17 through a desorption liquid outlet 9, and SO with the temperature of 65 ℃ is generated by desorption₂The mixed gas with the water vapor enters a steam heating chamber 3 of the 2 nd stage cavitation desorption unit through an exhaust port 10. The desulfurization rich solution in the cavitation desorption chamber 2 of the first-stage cavitation desorption unit is cavitated at a set value of 65 ℃ and absorbs heat, so that the water vapor in the steam heating chamber 3 is condensed into condensed water, the condensed water is sent back to the heat source regenerative system by the condensed water pump 19 through the condensed water outlet 5, and the uncondensed gas is evacuated by the vacuum-pumping system 7 through the gas outlet 6.

(3) The desulfurization rich liquid entering the cavitation desorption chamber 2 of the 2 nd-stage cavitation desorption unit flows from the desorption liquid inlet 8 to the desorption liquid outlet 9 under the set liquid level and flow rate, and is subjected to heat exchange with 65 ℃ steam entering the steam heating chamber 3 of the current stage through the heating surface 1 to heat up to 60 ℃ cavitation desorption temperature value set by the cavitation desorption chamber 2 of the current stage to generate cavitation, SO that SO in the desulfurization rich liquid₂Desorbing, regenerating the basic aluminum sulfate, wherein the regenerated basic aluminum sulfate solution enters a regenerated liquid header 17 through a desorption liquid outlet 9, and SO with the temperature of 60 ℃ is generated by desorption₂And the mixed gas with the water vapor enters a steam heating chamber 3 of the final stage cavitation desorption unit through an exhaust port 10. The desulfurization rich solution in the cavitation desorption chamber 2 of the 2 nd-stage cavitation desorption unit generates cavitation at the set value of 60 ℃ to absorb heat, and the water vapor in the steam heating chamber 3 of the 2 nd-stage cavitation desorption unit is condensed into condensed water and is mixed with SO₂The gas is separated, and the gas is separated,the condensed water flows into the first-stage cavitation desorption unit cavitation desorption chamber 2 through the condensed water outlet 5, and SO is generated₂Gas is sent to SO from a vacuum pumping system 7 through a gas outlet 6₂Utilizing the process flow.

(4) The desulfurization rich liquid entering the cavitation desorption chamber 2 of the final stage cavitation desorption unit is subjected to heat exchange with 60 ℃ steam entering the steam heating chamber 3 of the current stage through the heating surface 1 and is heated to 55 ℃ cavitation desorption temperature value set by the cavitation desorption chamber 2 of the current stage to generate cavitation in the process that the desulfurization rich liquid flows from the desorption liquid inlet 8 to the desorption liquid outlet 9 at set liquid level and flow rate, SO that SO in the desulfurization rich liquid₂Desorbing, regenerating the basic aluminum sulfate, wherein the regenerated basic aluminum sulfate solution enters a regenerated liquid header 17 through a desorption liquid outlet 9, and the water vapor and SO with the temperature of 55 ℃ generated by desorption₂The mixed gas firstly enters the heat exchanger 13 under the action of the direct air cooling system 14, and carries out surface heat exchange with the desulfurization rich liquid from the desulfurization system 20 entering the heat exchange tube bundle of the heat exchanger 13, SO that part of water vapor is condensed, and the uncondensed water vapor and SO are₂The mixed gas enters a direct air cooling system 14; the condensed water in the heat exchanger 13 automatically flows into the desulfurization rich liquid header 15 by gravity; the desulfurization rich solution from the desulfurization system 20 enters the desulfurization rich solution header 15 after being heated by the heat exchanger 13.

(5) Water vapor and SO entering the direct air cooling system 14₂The mixed gas and the ambient air carry out surface heat exchange, and water vapor is condensed and is mixed with SO₂Gas separation, the condensed water flows through the condensed water tank to be collected and flows into the desulfurization rich liquid header 15 by gravity, SO₂The gas is sent to SO from a vacuum pumping system arranged in the direct air cooling system 14₂Utilizing the process flow.

(6) The regenerated alkaline aluminum sulfate solution entering the regenerated liquid header 17 is delivered to the desulfurization system 20 or partially delivered to the sulfate radical neutralization system by the regenerated liquid pump 18.

The related parameters of the system for entering and exiting the 3-stage desulfurization pregnant solution cavitation desorption sulfur dioxide can be adjusted and controlled by adopting the prior disclosed technology or method; continuously feeding the desulfurization rich solution into a heat exchanger 13 according to the step (1), and continuously maintaining the saturated steam pressure value corresponding to the set temperature in each stage of cavitation desorption chamber 2 in the step (1)Continuously sending water vapor at 70 ℃ into a steam heating chamber 3 of a primary cavitation desorption unit in the step (1), continuously discharging non-condensable gas in the steam heating chamber 3 of the primary cavitation desorption unit by a vacuumizing system 7 in the step (2), sending condensed water in the steam heating chamber 3 of the primary cavitation desorption unit to a heat source heat regenerative system by a condensed water pump 19, and continuously sending SO in the steps (3) and (4)₂Gas is sent to SO from a vacuum pumping system 7 through a gas outlet 6₂Continuously adding SO in step (5) by using the process flow₂The gas is sent to SO from a vacuum pumping system arranged in the direct air cooling system 14₂By means of the process flow, step (6) continuously conveys the regenerated alkaline aluminum sulfate solution entering the regenerated liquid header 17 to the desulfurization system 20 or partially to the sulfate radical neutralization system by the regenerated liquid pump 18. The continuous and stable operation of the system for desorbing the sulfur dioxide by cavitation of the 3-level desulfurization rich solution is realized according to the steps of the method.

Example 2

Taking a system for carrying out cavitation desorption on sulfur dioxide by using 3 stages of desulfurization rich liquid as an example, the cavitation desorption temperature of the basic aluminum sulfate desulfurization rich liquid in the cavitation desorption chamber 2 of the final stage cavitation desorption unit is set to be 55 ℃, the interstage temperature difference of the cavitation desorption temperatures of the desulfurization rich liquid of the adjacent two stages of cavitation desorption units is set to be 5 ℃, and the cavitation temperature of the desulfurization rich liquid of the same stage cavitation desorption unit and the steam or steam, SO in the steam heating chamber 3 are set to be 5 DEG C₂Setting the temperature difference of the mixed gas to be 5 ℃; the exhaust steam of a steam turbine operating at the backpressure of 31.16kPa is used as the supply for supplying cavitation desorption SO₂The heat source of heat is that the temperature of the steam corresponding to the steam turbine exhaust is about 70 ℃, and the steam jet pump 11 is not needed for heating. The depth of the desorbed liquid in each stage of cavitation desorption chamber 2 is set to be 300mm, and the flow speed of the desorbed liquid from the desorption liquid inlet 8 to the desorption liquid outlet 9 is set to be 0.05 m/s.

As shown in fig. 1, the construction of the system for 3-stage desulfurization pregnant solution cavitation desorption of sulfur dioxide is completely the same as that of embodiment 1, except that the steam turbine exhaust does not need to be heated by the steam jet pump 11, and the bypass valve 12 is opened.

The method for desorbing sulfur dioxide by cavitation of 3-stage desulfurization pregnant solution is completely the same as the embodiment 1 except that the exhaust steam of a turbine at 70 ℃ is directly sent into a steam heating chamber 3 of a first-stage cavitation desorption unit through a bypass valve 12 without the temperature rise of a steam jet pump 11.

The inventive concept is explained in detail herein using specific examples, and the above description of the embodiments is only used to help understand the core idea of the present invention. It should be understood that any obvious modifications, equivalents and other improvements made by those skilled in the art without departing from the spirit of the present invention are intended to be included within the scope of the present invention.

Claims

1. A system for desorbing sulfur dioxide by multi-stage desulfurization pregnant solution cavitation, which is characterized in that,

the device comprises a plurality of stages of cavitation desorption units, wherein each stage of cavitation desorption unit is divided into an upper chamber and a lower chamber by a heating surface, the upper chamber is a cavitation desorption chamber, and the lower chamber is a steam heating chamber;

2. The system according to claim 1, wherein the condensed water outlet of the steam heating chamber of each rear stage cavitation desorption unit is connected to the desorption liquid inlet of the cavitation desorption chamber of the previous stage cavitation desorption unit through a pipeline, and the gas outlets of the steam heating chambers of the second stage cavitation desorption unit to the last stage cavitation desorption unit are connected to the SO through a vacuum pumping system₂By utilizing the process flow, a gas outlet of a steam heating chamber of the primary cavitation desorption unit is provided with a vacuum pumping system, and a condensed water outlet of the steam heating chamber of the primary cavitation desorption unit is connected to a heat source heat regeneration system through a condensed water pump.

3. The system of claim 1, wherein a steam heating chamber steam inlet of the first stage cavitation desorption unit is connected with a steam jet pump and a bypass valve which are connected in parallel, and steam enters the steam heating chamber through the steam jet pump or the bypass valve.

4. The system according to claim 1, wherein a cavitation desorption chamber exhaust port of the last stage cavitation desorption unit is connected with a heat exchanger and a direct air cooling system, a gas side inlet of the heat exchanger is connected with a cavitation desorption chamber exhaust port of the last stage cavitation desorption unit, and a gas side outlet of the heat exchanger is connected with the direct air cooling system.

5. The system of claim 4, further comprising a desulfurization rich liquid header and a regeneration liquid header, wherein the desulfurization rich liquid header conveys the desulfurization rich liquid to the cavitation desorption chamber of each stage of cavitation desorption unit, and the cavitation desorption chamber of each stage of cavitation desorption unit desorbs SO₂Outputting the regenerated solution to the regenerated solution header; the water side inlet of the heat exchanger is connected with a desulfurization system, the water side outlet of the heat exchanger is connected with the desulfurization rich liquid header, the heat exchanger and the condensed water outlet of the direct air cooling system are connected with the desulfurization rich liquid header, and the vacuumizing system of the direct air cooling system is connected with SO₂Utilizing the process flow.

6. The system according to claim 1, wherein the cavitation temperature of the desulfurization rich liquid of the previous stage cavitation desorption unit is higher than that of the desulfurization rich liquid of the next stage cavitation desorption unit, and the steam temperature of the steam heating chamber of the same stage cavitation desorption unit is higher than that of the cavitation rich liquid of the cavitation desorption unit.