Process water and oxidant supply system for desulfurization operation

Abstract

The utility model discloses a process water and oxidant supply system for desulfurization operation. The process water and oxidant supply system comprises a process water storage tank, an oxidant storage tank, a process water pump, an oxidant pump, an oxidant mixer, an oxidant spray gun and a compressed air supply unit, the process water storage tank is communicated with the oxidant mixer through a process water pump; the oxidant storage tank is communicated with the oxidant mixer through an oxidant pump; the oxidant mixer is communicated with the oxidant spray gun, and the inlet end of the oxidant spray gun is also communicated with a compressed air supply unit; and an outlet of the oxidant spray gun is arranged in a flue before desulfurization in desulfurization operation. According to the system disclosed by the utility model, by optimizing pipeline design and valve configuration, the processes of diluting, mixing and the like of an oxidizing agent solution are realized while process water supply is realized, and the requirement of simultaneous supply of the process water and the oxidizing agent solution in the desulfurization process is met.

Description

Technical Field

[0001] The utility model belongs to the technical field of environmental protection, and in particular relates to a process water and oxidant supply system for desulfurization operation. Background Art

[0002] Semi-dry desulfurization is widely used in the field of flue gas desulfurization due to its advantages such as low water consumption, high sulfur efficiency and no wastewater discharge. Commonly used semi-dry desulfurization technologies include circulating fluidized bed (CFB) semi-dry desulfurization, rotary spray (SDA) and other semi-dry desulfurization. Research reports have pointed out that by spraying oxidizing solution (hydrogen peroxide, NaClO2, KMnO4, etc.) or oxidizing gas (ozone) into the flue before the desulfurization tower, NO in the flue gas can be oxidized to high-valent NO2, etc. Under the action of alkaline absorbent (generally calcium hydroxide) and water in the desulfurization tower, nitrogen oxides can be absorbed and reacted to generate Ca(NO3)2 and other substances, achieving the purpose of semi-dry desulfurization and synergistic oxidation and denitrification. Although increasing the injection of oxidizing solution can achieve the synergistic removal of multiple pollutants to a certain extent, in order to spray the oxidant solution at the concentration with the best mixing and oxidation effect, and in order to save transportation costs, high-concentration oxidant solution or powder is usually purchased, and an oxidant solution dilution and transportation unit needs to be set up. There is a process water system in the semi-dry desulfurization system, such as the process water used for quicklime digestion in the circulating fluidized bed semi-dry desulfurization, and the process water used for temperature adjustment and flushing of the desulfurization tower in the rotary spray semi-dry desulfurization. It is very meaningful to realize the supply of oxidant and process water in one system and achieve system optimization by simply superimposing simple equipment on the semi-dry desulfurization system. Utility Model Content

[0003] The purpose of the utility model is to overcome the problems of the prior art and disclose a process water and oxidant supply system for desulfurization operations. The system of the utility model can realize the dilution and mixing of the oxidant solution while realizing the process water supply by optimizing the pipeline design and valve configuration, thereby meeting the system's need for the simultaneous supply of process water and oxidant solution.

[0004] The purpose of the utility model is achieved through the following technical solutions:

[0005] A process water and oxidant supply system for desulfurization operation, the process water and oxidant supply system comprising: a process water storage tank, an oxidant storage tank, a process water pump, an oxidant pump, an oxidant mixer, an oxidant spray gun and a compressed air supply unit;

[0006] The process water storage tank is connected to the oxidant mixer via a process water pump;

[0007] The oxidant storage tank is connected to the oxidant mixer via an oxidant pump;

[0008] The oxidant mixer is in communication with the oxidant lance, and the inlet end of the oxidant lance is also in communication with a compressed air supply unit;

[0009] The outlet of the oxidant spray gun is arranged in the flue before desulfurization in the desulfurization operation.

[0010] According to a preferred embodiment, an oxidant process water regulating valve is provided between the process water pump and the oxidant mixer.

[0011] According to a preferred embodiment, an oxidant process water check valve is provided between the oxidant process water regulating valve and the oxidant mixer.

[0012] According to a preferred embodiment, the outlet end of the process water pump is further provided with a branch pipeline connected to the process water storage tank.

[0013] According to a preferred embodiment, the outlet end of the process water pump is further provided with a branch pipeline connected to a downstream process unit, and a desulfurization process water regulating valve and a flow meter are further provided between the outlet end of the process water pump and the downstream process unit.

[0014] According to a preferred embodiment, the outlet end of the oxidant pump is also provided with a branch pipeline connected to the oxidant storage tank.

[0015] According to a preferred embodiment, an oxidant regulating valve and a flow meter are provided between the oxidant pump and the oxidant mixer.

[0016] According to a preferred embodiment, an oxidant mixture check valve is further provided between the oxidant mixer and the oxidant spray gun.

[0017] According to a preferred embodiment, a compressed air regulating valve is provided between the compressed air supply unit and the oxidant spray gun.

[0018] According to a preferred embodiment, a compressed air check valve is provided between the compressed air regulating valve and the oxidant spray gun.

[0019] The above-mentioned main scheme of the utility model and its further optional schemes can be freely combined to form multiple schemes, all of which are schemes that can be adopted and claimed for protection by the utility model. After understanding the scheme of the utility model, those skilled in the art can understand that there are many combinations based on the existing technology and common knowledge, all of which are technical schemes to be protected by the utility model, and they are not exhaustively listed here.

[0020] Beneficial effects of the utility model:

[0021] The utility model system can not only meet the needs of circulating fluidized bed semi-dry desulfurization or rotary spray semi-dry desulfurization process water, but also has the ability to dilute and mix oxidants, thereby saving equipment investment and land occupation.

[0022] The utility model system has a regulating valve on the system pipeline, which can flexibly adjust the supply of process water and oxidant according to the flue gas volume, temperature and pollutant concentration in the flue gas.

[0023] The utility model provides a check valve on the pipeline of process water entering the mixer to prevent oxidant from flowing back and corroding the process water pipeline. The pipeline of oxidant entering the oxidant spray gun is provided with a check valve to prevent compressed air from entering the oxidant delivery pipeline, thereby improving the reliability of system operation.

[0024] The oxidant pump outlet and the process water outlet of the system of the utility model are both provided with circulation loops, thereby improving the stability of system operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the working principle of the utility model system;

[0026] Among them, 1 is a process water storage tank; 2 is an oxidant storage tank; 3 is a process water pump; 4 is an oxidant pump; 5 is a desulfurization process water regulating valve; 6 is an oxidant process water regulating valve; 7 is an oxidant regulating valve; 8 is a compressed air regulating valve; 9 is an oxidant process water check valve; 10 is a compressed air check valve; 11 is an oxidant mixer; 12 is an oxidant mixed liquid check valve; 13 is an oxidant spray gun. DETAILED DESCRIPTION

[0027] The following describes the implementation of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific implementations, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0028] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0029] In the description of the present utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate the orientation or position relationship based on the orientation or position relationship shown in the accompanying drawings, or the orientation or position relationship in which the utility model product is usually placed when in use, which is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0030] In addition, the terms "horizontal", "vertical", "overhanging" and the like do not mean that the components are required to be absolutely horizontal or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0031] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] In addition, the present utility model should point out that, in the present utility model, if the specific structure, connection relationship, position relationship, power source relationship, etc. are not specifically written out, the structure, connection relationship, position relationship, power source relationship, etc. involved in the present utility model are all known by technical personnel in this field on the basis of existing technology without creative work.

[0033] The utility model discloses a process water and oxidant supply system for desulfurization operation. The process water and oxidant supply system comprises: a process water storage tank 1 for storing process water, a process water pump 3 for conveying process water, an oxidant storage tank 2 for storing oxidant, an oxidant pump 4 for conveying high-concentration oxidant solution, an oxidant mixer 11 for mixing high-concentration oxidant and process water, an oxidant spray gun 13 for atomizing and spraying diluted oxidant, and a pipeline system and valve. The oxidant spray gun 13 of the technical design of the present application adopts compressed air atomization.

[0034] The outlet of the process water storage tank 1 is connected to the inlet of the process water pump 3. The process water pump 3 pressurizes the process water to 0.6-0.8MPa to meet the downstream use requirements of the process water. The outlet of the process water pump 3 is divided into three routes. The first route flows back to the process water storage tank 1. The loop design improves the flexibility and stability of the system operation; the second route goes to the downstream process of the process water (in the circulating fluidized bed semi-dry method, the process water goes to the quicklime (CaO) digester to digest the desulfurizer CaO into Ca(OH)2, and in the rotary spray semi-dry method, the process water goes to the desulfurization tower for temperature adjustment of the desulfurization tower and flushing of equipment pipelines). A desulfurization process water regulating valve 5 and a flow meter are provided on the pipeline to adjust the process water flow rate; the third route is connected to the oxidant mixer 11, and the process water volume is adjusted through the oxidant process water regulating valve 6, and the process water enters the oxidant mixer 11 through the oxidant process water check valve 9. The oxidant process water check valve 9 is between the oxidant mixer 11 and the oxidant process water regulating valve 6 to prevent the oxidant solution from flowing back and corroding the process water pipeline and valves. A stop valve is installed on the first process water pipeline for system debugging and equipment maintenance.

[0035] The outlet of the oxidant storage tank 2 is connected to the inlet of the oxidant pump 4. The oxidant pump 4 pressurizes the oxidant to 0.6-0.8MPa to meet the injection requirements of the oxidant spray gun 13. The outlet of the oxidant pump 4 is divided into two paths. The first path flows back to the oxidant storage tank 2. The loop design improves the flexibility and stability of the system operation; the second path enters the oxidant mixer 11 after the oxidant amount is adjusted by the oxidant regulating valve 7 on the pipeline, and is fully mixed with the third process water in the oxidant mixer 11 to dilute the high-concentration oxidant to a concentration suitable for spray gun injection and to ensure the mixing effect, forming a low-concentration oxidant solution. The low-concentration oxidant solution enters the oxidant spray gun 13 through the oxidant mixed liquid check valve 12.

[0036] The oxidant spray gun 13 is atomized by compressed air. The compressed air pipeline is connected to the oxidant spray gun 13. The compressed air pipeline is provided with a compressed air regulating valve 8, a flow meter and a compressed air check valve 10, which are respectively used to adjust the usage of compressed air and prevent the solution from flowing into the compressed air pipeline. The diluted low-concentration oxidant solution is atomized by compressed air to form fine droplets, which are mixed with the flue gas in the flue before desulfurization. The strong oxidizing property of the oxidant is used to oxidize the insoluble or slightly soluble NOx (mainly NO) in the flue gas into high-valent nitrogen oxides such as NO2 and N2O5 that are easily soluble in water. At the same time, it can also oxidize SO2 with low solubility into easily soluble SO3, and oxidize zero-valent mercury into soluble divalent mercury (Hg 2+ ), and then use a large amount of alkaline absorbent (generally the main component of alkaline absorbent is calcium hydroxide) sprayed in by semi-dry desulfurization to remove these pollutants together.

[0037] Example 1

[0038] The utility model system is applied to a circulating fluidized bed semi-dry desulfurization system.

[0039] The process water in the process water storage tank 1 is pressurized to 0.6-0.8MPa by the process water pump 3 and then transported. The outlet of the process water pump 3 is divided into three routes. The first route flows back to the process water storage tank 1. The second route goes to the quicklime (CaO) digester after the flow rate is adjusted by the desulfurization process water regulating valve 5 on the pipeline, and is used to digest the desulfurizer CaO into Ca(OH)2 to meet the process needs of the digester. The flow meter after the desulfurization process water regulating valve 5 is used to display the flow rate of the desulfurization process water; the third route of process water enters the oxidant mixer 11 after the flow rate is adjusted by the oxidant process water regulating valve 6 on the pipeline. The flow meter after the oxidant process water regulating valve 6 is used to display the flow rate of the oxidant process water.

[0040] The oxidant with a concentration of 25% to 35% in the oxidant storage tank 2 is pressurized to 0.6 to 0.8 MPa by the oxidant pump 4 and then transported. The outlet of the oxidant pump 4 is divided into two paths, one of which flows back to the oxidant storage tank 2, and the other flows into the oxidant mixer 11 after the flow rate is adjusted by the oxidant regulating valve 7 on the pipeline, and is mixed with the third process water entering the oxidant mixer 11 to dilute the oxidant concentration by 2 to 10 times. The flow meter after the oxidant regulating valve 7 is used to display the flow rate of the oxidant.

[0041] The pressure of the solution at the outlet of the oxidant mixer 11 is 0.5-0.7 MPa. After the diluted oxidant solution passes through the oxidant mixed liquid check valve 12, it is mixed with the compressed air supplied by the compressed air pipeline in the oxidant spray gun 13, and the diluted oxidant solution is atomized and mixed with the pollutants in the flue gas for reaction. The flow meter after the compressed air regulating valve 8 is used to display the flow rate of the compressed air. The valves in the system of the utility model are all in the open state, realizing the function of supplying process water and diluting the oxidant at the same time.

[0042] Example 2

[0043] The utility model system is applied in a rotary spray semi-dry desulfurization system.

[0044] The process water in the process water storage tank 1 is pressurized to 0.6-0.8MPa by the process water pump 3 and then transported. The outlet of the process water pump 3 is divided into three routes. The first route flows back to the process water storage tank 1, and the second route goes to the deacidification tower after the flow rate is adjusted by the oxidant process water regulating valve 6 on the pipeline, and is used for temperature adjustment of the deacidification tower and flushing of equipment pipelines to meet the process requirements of the deacidification tower; the third route of process water enters the oxidant mixer 11 after the flow rate is adjusted by the oxidant process water regulating valve 6 on the pipeline, and the flowmeter after the oxidant process water regulating valve 6 is used to display the flow rate of the oxidant process water.

[0045] The oxidant with a concentration of 25% to 35% in the oxidant storage tank 2 is pressurized to 0.6 to 0.8 MPa by the oxidant pump 4 and then transported. The outlet of the oxidant pump 4 is divided into two paths, one of which flows back to the oxidant storage tank 2, and the other flows into the oxidant mixer 11 after the flow rate is adjusted by the oxidant regulating valve 7 on the pipeline, and is mixed with the third process water entering the oxidant mixer 11 to dilute the oxidant concentration by 2 to 10 times. The flow meter after the oxidant regulating valve 7 is used to display the flow rate of the oxidant.

[0046] The pressure of the solution at the outlet of the oxidant mixer 11 is 0.5-0.7 MPa. After the diluted oxidant solution passes through the oxidant mixed liquid check valve 12, it is mixed with the compressed air supplied by the compressed air pipeline in the oxidant spray gun 13. The diluted oxidant solution is atomized by compressed air and mixed with the pollutants in the flue gas in the inlet flue. The flow meter after the compressed air regulating valve 8 is used to display the flow of compressed air. The valves in the system of the utility model are all in the open state, realizing the function of supplying process water and diluting oxidant at the same time.

[0047] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A process water and oxidant supply system for desulfurization operation, characterized in that: The process water and oxidant supply system comprises: a process water storage tank (1), an oxidant storage tank (2), a process water pump (3), an oxidant pump (4), an oxidant mixer (11), an oxidant spray gun (13) and a compressed air supply unit; The process water storage tank (1) is connected to the oxidant mixer (11) via a process water pump (3); The oxidant storage tank (2) is connected to the oxidant mixer (11) via the oxidant pump (4); The oxidant mixer (11) is in communication with the oxidant spray gun (13), and the inlet end of the oxidant spray gun (13) is also in communication with a compressed air supply unit; The outlet of the oxidant spray gun (13) is arranged in the flue before desulfurization in the desulfurization operation.

2. The process water and oxidant supply system according to claim 1, characterized in that An oxidant process water regulating valve (6) is provided between the process water pump (3) and the oxidant mixer (11).

3. The process water and oxidant supply system according to claim 2, characterized in that An oxidant process water check valve (9) is provided between the oxidant process water regulating valve (6) and the oxidant mixer (11).

4. The process water and oxidant supply system according to claim 1, characterized in that The outlet end of the process water pump (3) is also provided with a branch pipeline which is connected to the process water storage tank (1).

5. The process water and oxidant supply system according to claim 1, characterized in that The outlet end of the process water pump (3) is also provided with a branch pipeline connected to a downstream process unit. A desulfurization process water regulating valve (5) and a flow meter are also provided between the outlet end of the process water pump (3) and the downstream process unit.

6. The process water and oxidant supply system according to claim 1, characterized in that The outlet end of the oxidant pump (4) is also provided with a branch pipeline which is connected to the oxidant storage tank (2).

7. The process water and oxidant supply system according to claim 1, characterized in that An oxidant regulating valve (7) and a flow meter are provided between the oxidant pump (4) and the oxidant mixer (11).

8. The process water and oxidant supply system according to claim 1, characterized in that An oxidant mixed liquid check valve (12) is also provided between the oxidant mixer (11) and the oxidant spray gun (13).

9. The process water and oxidant supply system of claim 1, wherein: A compressed air regulating valve (8) is provided between the compressed air supply unit and the oxidant spray gun (13).

10. The process water and oxidant supply system according to claim 9, characterized in that A compressed air check valve (10) is provided between the compressed air regulating valve (8) and the oxidant spray gun (13).

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