System and method for treating desulfurization wastewater by using dry slag removal system of coal-fired power generation unit

Abstract

The invention relates to a system and method for treating desulfurization wastewater by using a dry slag removal system of a coal-fired unit, and the system comprises a dry slag bin which is provided with an input end, an output end and a level gage; the wastewater conveying device is connected with the input end; the pipeline residue filter is connected with the output end; the drainage device is connected with one end, far away from the output end, of the pipeline residue filter; the flow meter is arranged on the drainage device; the slag discharging device is connected with the end, close to the output end, of the pipeline slag filter, the slag discharging device comprises a pneumatic valve plate, and when the monitored value of the flow meter is zero, the pneumatic valve plate is opened, so that the stable effluent quality of the dry slag bin is guaranteed, the qualified effluent quality of the dry slag bin is guaranteed, and the water quality of the dry slag bin is guaranteed. And stable operation of a subsequent drainage device is further ensured.

Description

Technical Field

[0001] The invention relates to the technical field of wastewater treatment in coal-fired power plants, and in particular to a system and method for treating desulfurization wastewater by utilizing a dry slag removal system of a coal-fired generator set. Background Art

[0002] Wet desulfurization process is widely used in the treatment of flue gas generated by coal-fired power plants. However, this method will produce a large amount of desulfurization wastewater, and the composition of this type of wastewater is complex, usually including suspended matter, high concentrations of sulfites, sulfates, chlorides, fluorides and trace amounts of heavy metal ions (such as mercury, chromium, nickel, lead, etc.).

[0003] In order to achieve the standard discharge of desulfurization wastewater, the existing scheme often uses the "triple box + clarifier" method to achieve wastewater treatment, but this method of wastewater treatment usually has the following defects:

[0004] 1. Due to the general unstable operation of the wastewater cyclone, the water quality of the desulfurization wastewater entering the triple box is unstable, especially the suspended solids and pH value. It is necessary to frequently adjust the dosage of various types of reagents in the triple box, and it is impossible to ensure stable effluent water quality.

[0005] 2. Due to the land occupation and layout of the desulfurization workshop, the volume of the general triple box is small (each box is about 5 cubic meters), the wastewater stays in the triple box for a short time, the wastewater cannot be fully mixed with the reagent, and it is easy to cause the effluent water quality to be unqualified.

[0006] That is, the existing scheme cannot guarantee stable effluent water quality during wastewater treatment, and is likely to result in unqualified effluent water quality, which will seriously affect the operation effect of the subsequent clarification tank.

[0007] Therefore, it is urgent for those skilled in the art to provide a system and method for treating desulfurization wastewater using a dry slag removal system of a coal-fired power generation unit to ensure stable effluent water quality and qualified effluent water quality. Summary of the invention

[0008] The technical problem to be solved by the present invention is to overcome the defects in the prior art, thereby providing a system and method for treating desulfurization wastewater by using a dry slag removal system of a coal-fired power generation unit.

[0009] To achieve the above object, the present invention adopts the following technical solutions:

[0010] A system for treating desulfurization wastewater using a dry slag removal system of a coal-fired generator set, comprising:

[0011] A dry slag bin with an input port, an output port and a level meter;

[0012] A wastewater conveying device connected to the input end;

[0013] A pipeline filter connected to the output end;

[0014] A drainage device connected to an end of the pipeline filter away from the output end;

[0015] A flow meter, arranged on the drainage device;

[0016] A slag discharge device is connected to one end of the pipeline filter close to the output end. The slag discharge device includes a pneumatic valve plate. When the flow meter monitoring value is zero, the pneumatic valve plate opens.

[0017] Preferably, the drainage device includes a wastewater parameter monitoring instrument, a wastewater clarification treatment component and a wastewater branch return component;

[0018] The wastewater parameter monitoring instrument is located upstream of the wastewater clarification treatment component and the wastewater branch return component;

[0019] One end of the wastewater branch reflux component is connected to the pipeline filter, and the other end is connected to the output end;

[0020] The wastewater clarification treatment component includes a first pneumatic valve group, and the wastewater branch reflux component includes a second pneumatic valve group to control the conduction of the wastewater clarification treatment component or the wastewater branch reflux component.

[0021] Preferably, the wastewater parameter monitoring instrument includes at least a turbidity meter and a pH meter.

[0022] Preferably, the wastewater branch return assembly further includes a pipeline booster pump, a first control valve, a first check valve and a first normally closed valve;

[0023] The pipeline filter, the second pneumatic valve group, the pipeline booster pump, the first control valve, the first check valve, the first normally closed valve and the input end are connected in sequence.

[0024] Preferably, the wastewater clarification treatment component further comprises a clarification tank, a water tank, a liquid level meter and a water-liquid reuse pipeline;

[0025] The upper end of the clarifier tank is connected to the water tank, so as to store the clarified water in the water tank;

[0026] The liquid level meter is installed at a preset position of the water tank.

[0027] Preferably, the input end is used to communicate with the slag conveying equipment of the dry slag removal system to convey the slag of a preset temperature to the dry slag bin;

[0028] The preset temperature of the filter residue is in the range of 100-180° C.; the slag has different particle sizes.

[0029] Preferably, the wastewater conveying device comprises a conveying pipe, a third pneumatic valve group installed on the conveying pipe, and a water inlet pipe connecting the conveying pipe and the output end;

[0030] The third pneumatic valve group includes a third pneumatic butterfly valve and a third normally open manual butterfly valve connected to both ends of the third pneumatic butterfly valve.

[0031] A method for treating desulfurization wastewater using a dry slag removal system of a coal-fired generator set based on the above system comprises the following steps:

[0032] Monitor the real-time storage amount of dry slag in the dry slag bin;

[0033] When the real-time storage volume exceeds the preset storage volume, the desulfurization wastewater is transported to the dry slag bin;

[0034] In the process of treating desulfurization wastewater in the dry slag bin, the wastewater and waste slag output from the dry slag bin are filtered by a pipeline filter, and a drainage device is turned on and a slag discharge device is turned off;

[0035] The wastewater flow of the drainage device is monitored, and when the wastewater flow is zero, the slag discharge device is turned on.

[0036] Preferably, the method further comprises the following steps:

[0037] Monitoring parameters of wastewater transported from the pipeline filter to the drainage device, wherein the parameters include at least real-time turbidity and real-time pH value;

[0038] When the real-time turbidity is lower than the preset turbidity value and the real-time pH value is higher than the preset pH value, the wastewater clarification treatment component is turned on; when the real-time turbidity is higher than the preset turbidity value or the real-time pH value is lower than the preset pH value, the wastewater branch reflux component is turned on.

[0039] Preferably, the method further comprises the following steps:

[0040] Clarifying the water injected into the clarifier tank through the first pneumatic valve group, and storing the clarified water in a water tank;

[0041] The real-time liquid level value in the water tank is monitored, and when the real-time liquid level value exceeds a preset liquid level value, the water in the water tank is pressurized through a water-liquid reusing pipeline for reuse.

[0042] Compared with the prior art, the present invention has the following beneficial effects:

[0043] The above scheme provides a system for treating desulfurization wastewater by using the dry slag removal system of a coal-fired power generation unit. The desulfurization wastewater is introduced into the dry slag bin through a wastewater conveying device, and the slag in the dry slag bin can be used to treat the desulfurization wastewater. On the one hand, it can effectively improve the pH value of the desulfurization wastewater without adding other auxiliary materials, which is convenient for removing heavy metals using organic sulfur in the subsequent drainage device. On the other hand, the dry slag bin has a large volume and contains a sufficient amount of slag. The residence time of the desulfurization wastewater in the dry slag bin can be effectively guaranteed, and the slag has different particle sizes and a large specific surface area. It has a certain adsorption effect on harmful substances in the desulfurization wastewater, and can remove most of the suspended matter in the desulfurization wastewater without adding other auxiliary materials, and can effectively solve the fluctuation of the desulfurization wastewater quality, ensure stable effluent water quality and qualified effluent water quality, and further ensure the stable operation of the subsequent drainage device. In addition, in this scheme, through the arrangement of the drainage device, pipeline filter, slag discharge device and flow meter, the pipeline filter can separate the wastewater and waste residue output from the output end, and the flow meter can monitor the flow of wastewater. When the flow of wastewater is not zero, the pneumatic valve plate of the slag discharge device is in a closed state, so as not to affect the drainage of the drainage device; and when the flow of wastewater is zero, the pneumatic valve plate of the slag discharge device is in an open state, so as to avoid wastewater being mixed in the waste residue and affecting the reuse of the waste residue. Correspondingly, the method for treating desulfurization wastewater using the dry slag removal system of a coal-fired power generation unit provided by the above scheme has the advantages of ensuring stable effluent water quality and ensuring qualified effluent water quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0045] Figure 1 A schematic diagram of the structure of one example of the system provided by the present invention.

[0046] Description of reference numerals:

[0047] 100. Slag conveying equipment; 1. Dry slag bin; 11. Input end; 12. Output end; 13. Material level meter; 2. Wastewater conveying device; 21. Conveying pipe; 22. Third pneumatic valve group; 221. Third pneumatic butterfly valve; 222. Third normally open manual butterfly valve; 23. Water inlet pipe; 3. Pipe filter; 4. Drainage device; 41. Wastewater parameter monitoring instrument; 411. Turbidimeter; 412. pH meter; 42. Wastewater clarification treatment component; 421. First pneumatic valve group; 4211. First pneumatic butterfly valve; 4212. The first normally open manual butterfly valve; 422, clarification tank; 423, water tank; 424, liquid level meter; 425, water-liquid reuse pipeline; 43, wastewater branch reflux component; 431, second pneumatic valve group; 4311, second pneumatic butterfly valve; 4312, second normally open manual butterfly valve; 432, pipeline booster pump; 433, first control valve; 434, first check valve; 435, first normally closed valve; 5, flow meter; 6, slag discharge device; 61, pneumatic valve plate; 62, flexible joint; 63, manual gate plate; 64, electric air remover. DETAILED DESCRIPTION

[0048] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only 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.

[0049] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying 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 limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0050] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" 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.

[0051] The existing desulfurization wastewater is highly acidic, with a pH value between 2 and 5, and suspended solids fluctuating between hundreds and tens of thousands. In order to achieve standard discharge of desulfurization wastewater, the desulfurization wastewater is usually adjusted from highly acidic to weakly alkaline, and then organic sulfur is added to remove heavy metal ions, and finally flocculants and coagulants are added to remove suspended solids and gypsum in the wastewater.

[0052] See also Figure 1 An embodiment of the present invention provides a system for treating desulfurization wastewater using a dry slag removal system of a coal-fired power generation unit, comprising a dry slag bin 1, a wastewater conveying device 2, a pipeline slag filter 3, a drainage device 4, a flow meter 5 and a slag removal device 6.

[0053] Specifically, the dry slag bin 1 has an input end 11, an output end 12 and a material level meter 13; the wastewater conveying device 2 is connected to the input end 11; the pipeline filter 3 is connected to the output end 12; the drainage device 4 is connected to the end of the pipeline filter 3 away from the output end 12; the flow meter 5 is arranged on the drainage device 4; the slag discharge device 6 is connected to the end of the pipeline filter 3 close to the output end 12, and the slag discharge device 6 includes a pneumatic valve plate 61. When the monitoring value of the flow meter 5 is zero, the pneumatic valve plate 61 is opened.

[0054] Since the slag of the coal-fired power generation unit (i.e. the slag stored in the dry slag bin 1 by the dry slag removal system) is mainly composed of silicon dioxide, aluminum oxide, iron oxide, calcium oxide, magnesium oxide, etc., it is usually crushed to between 5mm and 40mm before being introduced into the dry slag bin 1 for storage, and the proportion of slag with a particle size of 5mm does not exceed 40%. In addition, the dry slag bin 1 of this size is usually large in volume, and the layer height of the slag in the slag bin is about 6m.

[0055] It can be seen that, compared with the existing desulfurization wastewater treatment method, in the above scheme, the desulfurization wastewater is introduced into the dry slag bin 1 through the wastewater conveying device 2, and the slag in the dry slag bin 1 can be used to treat the desulfurization wastewater. On the one hand, it can effectively improve the pH value of the desulfurization wastewater without adding other auxiliary materials, which is convenient for the subsequent drainage device 4 to remove heavy metals using organic sulfur. On the other hand, the dry slag bin 1 has a large internal volume and contains a sufficient amount of slag. The residence time of the desulfurization wastewater in the dry slag bin 1 can be effectively guaranteed, and the slag has different particle sizes and a large specific surface area, which has a certain adsorption effect on harmful substances in the desulfurization wastewater, thereby achieving the removal of most of the suspended matter in the desulfurization wastewater without adding other auxiliary materials, thereby effectively solving the fluctuation of the desulfurization wastewater water quality, ensuring stable effluent water quality and qualified effluent water quality, and further ensuring the stable operation of the subsequent drainage device 4. In addition, in the present scheme, through the arrangement of the drainage device 4, the pipeline filter 3, the slag discharge device 6 and the flow meter 5, the pipeline filter 3 can separate the wastewater and waste slag outputted from the output end 12, and the flow meter 5 can monitor the flow of the wastewater. When the flow of the wastewater is not zero, the pneumatic valve plate 61 of the slag discharge device 6 is in a closed state, thereby not affecting the drainage of the drainage device 4; and when the flow of the wastewater is zero, the pneumatic valve plate 61 of the slag discharge device 6 is in an open state, thereby avoiding the wastewater from being mixed in the waste slag, thereby affecting the recycling of the waste slag.

[0056] In order to further ensure the output of qualified effluent water quality and thus ensure the stable operation of the drainage device 4, in this embodiment, the drainage device 4 includes a wastewater parameter monitoring instrument 41, a wastewater clarification treatment component 42 and a wastewater branch reflux component 43. Among them, the wastewater parameter monitoring instrument 41 is located upstream of the wastewater clarification treatment component 42 and the wastewater branch reflux component 43; one end of the wastewater branch reflux component 43 is connected to the pipeline filter 3, and the other end is connected to the output end 12; the wastewater clarification treatment component 42 includes a first pneumatic valve group 421, and the wastewater branch reflux component 43 includes a second pneumatic valve group 431 to control the conduction of the wastewater clarification treatment component 42 or the wastewater branch reflux component 43.

[0057] Furthermore, the wastewater parameter monitoring instrument 41 at least includes a turbidity meter 411 and a pH meter 412 .

[0058] It can be known that the wastewater parameter monitoring instrument 41 can monitor the parameters of the wastewater transported from the pipeline filter 3 to the drainage device 4, and the parameters include at least real-time turbidity and real-time pH value, and then the real-time turbidity can be compared with the turbidity preset value (set based on the parameters of qualified wastewater), and the real-time pH value can be compared with the pH preset value (set based on the parameters of qualified wastewater). When the real-time turbidity is lower than the turbidity preset value and the real-time pH value is higher than the pH preset value, the wastewater clarification treatment component 42 is turned on to achieve wastewater clarification treatment. When the real-time turbidity is higher than the turbidity preset value or the real-time pH value is lower than the pH preset value, the wastewater branch reflux component 43 is turned on so that the unqualified wastewater can flow back to the dry residue bin 1 for secondary treatment. In addition, a corresponding control valve can also be set between the pipeline filter 3 and the wastewater parameter monitoring instrument 41.

[0059] Specifically, the wastewater branch reflux assembly 43 also includes a pipeline booster pump 432, a first control valve 433, a first check valve 434 and a first normally closed valve 435; the pipeline filter 3, the second pneumatic valve group 431, the pipeline booster pump 432, the first control valve 433, the first check valve 434, the first normally closed valve 435 and the input end 11 are connected in sequence. Among them, the second pneumatic valve group 431 may include a second pneumatic butterfly valve 4311 and a second normally open manual butterfly valve 4312 located upstream and downstream of the second pneumatic butterfly valve 4311. In addition, the first normally closed valve 435 and the first control valve 433 can be set as manually controlled butterfly valves.

[0060] Further, the wastewater clarification treatment component 42 also includes a clarifier 422, a water tank 423, a liquid level meter 424 and a water reuse pipeline 425; the upper end of the clarifier 422 is connected to the downstream of the pipeline filter 3 through the first pneumatic valve group 421; the upper end of the clarifier 422 is connected to the water tank 423 to store the clarified water in the water tank 423; the liquid level meter 424 is installed at a preset position of the water tank 423 to monitor the real-time liquid level value of the water tank 423. When the real-time liquid level value in the water tank 423 exceeds the preset liquid level value, or when water is needed, the water in the water tank 423 is pressurized for reuse through the water reuse pipeline 425. Among them, the first pneumatic valve group 421 may include a first pneumatic butterfly valve 4211 and a first normally open manual butterfly valve 4212. An agitator can be installed in the clarification tank 422, and a mud discharge pipe assembly is connected to the lower end of the clarification tank 422. In this solution, impurities in the wastewater treated by the dry slag bin 1 can be greatly reduced, thereby effectively reducing the mud discharge amount of the mud discharge pipe assembly.

[0061] It is worth noting that, during the water clarification process, organic sulfur and a small amount of coagulant and flocculant can be added to the clarification tank 422. It can be understood that the input of flocculant and flocculant at the beginning of the desulfurization wastewater treatment (i.e. before the wastewater is input into the drainage device 4) is reduced in this solution, and the amount of coagulant and flocculant added to the clarification tank 422 can also be reduced to a certain extent.

[0062] It can be known that when wastewater needs to flow back, the pipeline booster pump 432, the first control valve 433, the first normally closed valve 435 and the second pneumatic butterfly valve 4311 of the second pneumatic valve group 431 are opened, and the first pneumatic butterfly valve 4211 of the first pneumatic valve group 421 is closed.

[0063] See also Figure 1 The input end 11 is used to communicate with the slag conveying device 100 of the dry slag removal system to convey the slag of a preset temperature to the dry slag bin 1; the preset temperature range of the filter slag is 100 to 180° C.; the slag has different particle sizes.

[0064] It can be known that the temperature of the slag discharged from the furnace is about 700°C. After cooling with air and suction by negative pressure in the furnace, the temperature of the slag entering the dry slag bin 1 is generally between 100 and 180°C. The present invention utilizes the heat of the slag itself to evaporate and reduce the amount of desulfurization wastewater, which can effectively reduce the amount of desulfurization wastewater entering the subsequent process and achieve concentration and reduction of desulfurization wastewater.

[0065] See also Figure 1 The wastewater conveying device 2 includes a conveying pipe 21, a third pneumatic valve group 22 installed on the conveying pipe 21, and a water inlet pipe 23 connecting the conveying pipe 21 and the output end 12; the third pneumatic valve group 22 includes a third pneumatic butterfly valve 221 and a third normally open manual butterfly valve 222 connected to both ends of the third pneumatic butterfly valve 221.

[0066] See also Figure 1 The slag discharge device 6 also includes a flexible joint 62, a manual gate plate 63 and an electric air remover 64; the flexible joint 62, the manual gate plate 63, the pneumatic valve plate 61 and the electric air remover 64 are sequentially connected through a slag discharge pipeline. The setting of the flexible joint 62 can prevent the slag discharge outlet from shaking due to system vibration.

[0067] The embodiment of the present invention also provides a method for treating desulfurization wastewater by using a dry slag removal system of a coal-fired power generation unit based on the above system, which specifically includes the following steps:

[0068] Monitor the real-time storage amount of dry slag in dry slag bin 1;

[0069] When the real-time storage volume exceeds the preset storage volume, the desulfurization wastewater is transported to the dry slag bin 1. The preset storage volume can be set according to the desulfurization wastewater treatment requirements, such as being set to 70% of the storage volume of the dry slag bin 1.

[0070] In the process of treating desulfurization wastewater in the dry slag bin 1 , the pipeline filter 3 is used to filter the wastewater and waste slag output from the dry slag bin 1 , and the drainage device 4 is turned on and the slag discharge device 6 is closed.

[0071] The wastewater flow rate of the drainage device 4 is monitored, and when the wastewater flow rate is zero, the slag discharge device 6 is turned on to discharge the waste slag.

[0072] Furthermore, the method further comprises the following steps:

[0073] Monitoring parameters of wastewater transported from the pipeline filter 3 to the drainage device 4, the parameters at least including real-time turbidity and real-time pH value;

[0074] When the real-time turbidity is lower than the preset turbidity value and the real-time pH value is higher than the preset pH value, the wastewater clarification treatment component 42 is turned on; when the real-time turbidity is higher than the preset turbidity value or the real-time pH value is lower than the preset pH value, the wastewater branch reflux component 43 is turned on.

[0075] Furthermore, the method further comprises the following steps:

[0076] Clarify the water injected into the clarification tank 422 through the first pneumatic valve group 421, and store the clarified water in the water tank 423;

[0077] The real-time liquid level value in the water tank 423 is monitored. When the real-time liquid level value exceeds the preset liquid level value, the water in the water tank 423 is pressurized through the water reuse pipeline 425 for reuse.

[0078] In summary, the above system and method are used to illustrate a specific desulfurization wastewater process, and the specific process is as follows:

[0079] Step 1: Check and ensure that the pneumatic valve plate 61, the first pneumatic valve group 421, the second pneumatic valve group 431, the third pneumatic valve group 22, the first control valve 433, and the first normally closed valve 435 are all in a closed state.

[0080] Step 2: Use the material level meter 13 to monitor the real-time storage volume of the slag in the dry slag bin 1. When the real-time storage volume exceeds the preset storage volume (i.e. 70% of the storage volume of the dry slag bin 1), open the third pneumatic valve group 22.

[0081] Step 3: Desulfurization wastewater is transported to the input end 11 at the upper end of the dry slag bin 1 through the delivery pipe 21, the third pneumatic valve group 22 and multiple water inlet pipes 23, so that the desulfurization wastewater is sprayed into the dry slag bin 1, and is transferred from the input end 11 to the output end 12 under the action of gravity. In this process, the desulfurization wastewater contacts the surface of slag with different particle sizes and a certain temperature range, so that the slag filters the desulfurization wastewater (removes most of the suspended matter), adjusts the pH value (metal oxides in the slag form alkaline slag water when they meet water) and evaporates and concentrates (the slag temperature is generally between 100 and 180°C), so that the output end 12 of the dry slag bin 1 maintains stable effluent water quality and qualified effluent water quality. It is worth noting that, generally speaking, after the desulfurization wastewater is treated with dry slag, the suspended matter is less than 1000 mg / L, the pH is greater than 8, and the concentration reduction per hour is greater than 3m 3 .

[0082] Step 4: The wastewater and waste residue outputted through the output end 12 are filtered by the pipeline filter 3, the waste residue is separated upstream of the pipeline filter 3, and the wastewater flows through the pipeline filter 3 and is monitored by the flow meter 5, the turbidity meter 411, and the pH meter 412. When the real-time turbidity is lower than the preset turbidity value and the real-time pH value is higher than the preset pH value, the wastewater clarification treatment component 42 is turned on and step 5 is executed; when the real-time turbidity is higher than the preset turbidity value or the real-time pH value is lower than the preset pH value, the wastewater branch reflux component 43 is turned on to allow the wastewater to flow back to the dry residue bin 1 for secondary treatment; when the flow meter 5 detects that the wastewater flow is zero, the slag discharge device 6 is turned on to discharge the waste residue using the slag discharge device 6.

[0083] Step 5: Add a certain amount of flocculant, coagulant aid, and organic sulfur to the wastewater injected into the wastewater clarification treatment component 42 to remove the remaining suspended solids and heavy metals in the desulfurization wastewater, and store the clarified water in the water tank 423. At the same time, the real-time liquid level value in the water tank 423 is monitored by the liquid level meter 424. When the real-time liquid level value exceeds the preset liquid level value, the water in the water tank 423 is pressurized through the water reuse pipeline 425 for reuse.

[0084] It is worth noting that the control of the valves mentioned above can be achieved by using a control system.

[0085] The above-mentioned embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and substitutions made by technicians in this field on the basis of the present invention shall fall within the scope of protection required by the present invention.

Claims

1. A system for treating desulfurization wastewater using a dry slag removal system of a coal-fired power generation unit, characterized in that: include: A dry slag bin (1) having an input end (11), an output end (12) and a material level meter (13); A wastewater conveying device (2) connected to the input end (11); A pipeline filter (3) connected to the output end (12); A drainage device (4) connected to an end of the pipeline filter (3) away from the output end (12); A flow meter (5) is arranged on the drainage device (4); A slag discharge device (6) is connected to one end of the pipeline filter (3) close to the output end (12), and the slag discharge device (6) includes a pneumatic valve plate (61). When the value monitored by the flow meter (5) is zero, the pneumatic valve plate (61) opens.

2. A system for treating desulfurization wastewater using a dry slag removal system of a coal-fired power generation unit according to claim 1, characterized in that: The drainage device (4) comprises a wastewater parameter monitoring instrument (41), a wastewater clarification treatment component (42) and a wastewater branch return component (43); The wastewater parameter monitoring instrument (41) is located upstream of the wastewater clarification treatment component (42) and the wastewater branch return component (43); One end of the wastewater branch reflux component (43) is connected to the pipeline filter (3), and the other end is connected to the output end (12); The wastewater clarification treatment component (42) includes a first pneumatic valve group (421), and the wastewater branch return flow component (43) includes a second pneumatic valve group (431) to control the conduction of the wastewater clarification treatment component (42) or the wastewater branch return flow component (43).

3. A system for treating desulfurization wastewater using a dry slag removal system of a coal-fired power generation unit according to claim 2, characterized in that: The wastewater parameter monitoring instrument (41) comprises at least a turbidity meter (411) and a pH meter (412).

4. A system for treating desulfurization wastewater using a dry slag removal system of a coal-fired power generation unit according to claim 2, characterized in that: The wastewater branch return assembly (43) further includes a pipeline booster pump (432), a first control valve (433), a first check valve (434) and a first normally closed valve (435); The pipeline filter (3), the second pneumatic valve group (431), the pipeline booster pump (432), the first control valve (433), the first check valve (434), the first normally closed valve (435) and the input end (11) are connected in sequence.

5. A system for treating desulfurization wastewater using a dry slag removal system of a coal-fired power generation unit according to claim 2, characterized in that: The wastewater clarification treatment component (42) further includes a clarification tank (422), a water tank (423), a liquid level meter (424) and a water-liquid reuse pipeline (425); The upper end of the clarification tank (422) is connected to the water tank (423) so as to store the clarified water in the water tank (423); The liquid level meter (424) is installed at a preset position of the water tank (423).

6. A system for treating desulfurization wastewater using a dry slag removal system of a coal-fired power generation unit according to claim 1, characterized in that: The input end (11) is used to communicate with a slag conveying device (100) of a dry slag removal system so as to convey slag of a preset temperature to the dry slag bin (1); The preset temperature of the filter residue is in the range of 100-180° C.; the slag has different particle sizes.

7. The system for treating desulfurization wastewater using a dry slag removal system of a coal-fired power generation unit according to claim 1, characterized in that: The wastewater conveying device (2) comprises a conveying pipe (21), a third pneumatic valve group (22) installed on the conveying pipe (21), and a water inlet pipe (23) connecting the conveying pipe (21) and the output end (12); The third pneumatic valve group (22) comprises a third pneumatic butterfly valve (221) and a third normally open manual butterfly valve (222) connected to both ends of the third pneumatic butterfly valve (221).

8. A method for treating desulfurization wastewater using a dry slag removal system of a coal-fired power generation unit based on the system described in any one of claims 1 to 7, characterized in that: The following steps are involved: Monitoring the real-time storage amount of dry slag in the dry slag bin (1); When the real-time storage volume exceeds the preset storage volume, the desulfurization wastewater is transported to the dry slag bin (1); In the process of treating desulfurization wastewater in the dry residue bin (1), the wastewater and waste residue output from the dry residue bin (1) are filtered using a pipeline residue filter (3), and a drainage device (4) is turned on and a residue discharge device (6) is turned off; The wastewater flow rate of the drainage device (4) is monitored, and when the wastewater flow rate is zero, the slag discharge device (6) is turned on.

9. The method for treating desulfurization wastewater using a dry slag removal system of a coal-fired power generation unit according to claim 8, characterized in that: The following steps are also included: Monitoring parameters of the wastewater transported from the pipeline filter (3) to the drainage device (4), wherein the parameters at least include real-time turbidity and real-time pH value; When the real-time turbidity is lower than the preset turbidity value and the real-time pH value is higher than the preset pH value, the wastewater clarification treatment component (42) is turned on; when the real-time turbidity is higher than the preset turbidity value or the real-time pH value is lower than the preset pH value, the wastewater branch reflux component (43) is turned on.

10. The method for treating desulfurization wastewater using a dry slag removal system of a coal-fired power generation unit according to claim 8, characterized in that: The following steps are also included: Clarifying the water injected into the clarification tank through the first pneumatic valve group, and storing the clarified water in a water tank (423); The real-time liquid level value in the water tank (423) is monitored, and when the real-time liquid level value exceeds a preset liquid level value, the water in the water tank (423) is pressurized through a water-liquid reusing pipeline (425) for reuse.

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