Water-saving high-salinity device and process for vacuum belt conveyor

Abstract

The invention discloses a water-saving high-salt device and process for a vacuum belt conveyor, and a first vacuum tank and a second vacuum tank are arranged in the vacuum belt conveyor and are respectively arranged at the front section and the rear section of the vacuum belt conveyor. The energy-saving high-salinity device further comprises a first steam-water separator, a clarification water tank, a clear water tank, a booster water pump, a second steam-water separator, a filtrate water tank, a vacuum pump, a filter, a flushing water tank, a flushing water pump and a gypsum bin. The vacuum belt conveyor is functionally divided, a high-salinity water system is implemented in the front section, and a low-salinity water system is implemented in the rear section; the clarified filtrate is used as part of lubricating water and sealing water of the vacuum belt conveyor, so that the consumption of process water and clear water consumed by the vacuum belt conveyor is reduced, and the aim of saving water is fulfilled; meanwhile, the filtrate water of the high-salt system enters the desulfurization wastewater zero-discharge system for further concentration and evaporation of high salt, so that the energy consumption of the desulfurization wastewater zero-discharge system is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of limestone-gypsum wet desulfurization, and more specifically, relates to a water-saving high-salt device and process for a desulfurization vacuum belt conveyor. Background Art

[0002] In recent years, the "Water Pollution Prevention and Control Action Plan" (referred to as the "Water Ten") issued by the State Council has put forward clear goals and requirements for the prevention and control of wastewater pollution. Desulfurization wastewater has complex components, large changes in water quality, great harm, and is difficult to treat. It has become the focus of the next step in the treatment of coal-fired power plant wastewater pollution. In the wastewater treatment system of the limestone-gypsum wet desulfurization process of thermal power plants, the vacuum belt conveyor side requires a large amount of process water and generates a large amount of wastewater. The existing vacuum belt conveyor treatment process has the problem of high water and energy consumption. Summary of the invention

[0003] In view of the above-mentioned problems, the present invention provides a water-saving high-salt device and process for a vacuum belt conveyor. The present invention divides the vacuum belt conveyor into functions, implements a high-salt concentration water system in the front section, and implements a low-salt concentration water system in the rear section. The high-salt system and the low-salt system are used as lubricating water and sealing water in the front and rear sections respectively, thereby achieving the goal of saving water and energy. The filtrate separated by the vacuum belt conveyor is divided into two types, one is slurry and the other is mixed filtrate. The vacuum tank inside the vacuum belt conveyor is divided into two parts. The mixed slurry filtered out from the vacuum tank in the front half of the liquid phase is discharged to the clarified water tank through the lower part of the steam-water separator. Part of the clarified clear liquid is used for the high-concentration sealing water and lubricating water in the front of the vacuum belt conveyor, and the other part enters the desulfurization wastewater zero discharge system for high-salt concentration and evaporation. The concentrated slurry and bottom mud at the bottom of the clarified water tank are returned to the desulfurization reuse water system. The process water (filter cloth washing water) is arranged on the upper part of the vacuum tank at the rear of the vacuum belt conveyor to wash the gypsum so that the gypsum meets the quality requirements. The liquid phase (mixed filtrate) in the rear vacuum tank is discharged to the filtrate water tank through the lower part of the steam-water separator and returned to the desulfurization reuse water system. The gas phases at the front and rear are all discharged into the atmosphere through the vacuum pump, and part of the liquid flows to the flushing water tank by gravity. This part of low-concentration flushing water is used for low-concentration sealing water and lubricating water at the rear of the vacuum belt conveyor, and the other part is returned to the desulfurization reuse water system.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is: A water-saving high-salt device for a vacuum belt conveyor comprises a high-salt concentration water system and a low-salt concentration water system. The vacuum tank inside the vacuum belt conveyor is divided into a first vacuum tank and a second vacuum tank. The high-salt concentration water system comprises the first vacuum tank, a first steam-water separator, a clarified water tank, a clean water tank and a booster water pump; the low-salt concentration water system comprises the second vacuum tank, a second steam-water separator, a filtrate water tank, a flushing water tank and a flushing water pump.

[0005] Furthermore, the filtrate outlet of the first vacuum tank is connected to the inlet of the first steam-water separator, the liquid phase outlet of the first steam-water separator is connected to the inlet of the clarified water tank, the clear liquid outlet of the clarified water tank is connected to the inlet of the clean water tank, the sludge outlet of the clarified water tank is connected to the desulfurization recycled water system, the outlet of the clean water tank is connected to the booster water pump and then divided into two branches, one branch is connected to the desulfurization wastewater zero discharge system, and the other branch is connected to the vacuum belt conveyor in the front half.

[0006] Furthermore, the filtrate outlet of the second vacuum tank is connected to the inlet of the second steam-water separator, the liquid phase outlet of the second steam-water separator is connected to the inlet of the filtrate water tank, and the outlet of the filtrate water tank is connected to the desulfurization reuse water system.

[0007] Furthermore, the gas phase outlets of the first steam-water separator and the second steam-water separator are connected to each other and are connected to a vacuum pump and a filter in sequence. The gas phase outlet of the filter is connected to the atmosphere, and the vacuum pump is connected to a process water delivery pipeline.

[0008] Furthermore, the liquid phase outlet of the filter is connected to the inlet of the flushing water tank, and the outlet of the flushing water tank is divided into two branches, one branch is connected to the desulfurization reuse water system, and the other branch is connected to the flushing water pump and then to the vacuum belt conveyor in the rear half.

[0009] Furthermore, the first vacuum tank is connected to a gypsum cyclone station to convey waste liquid to be treated, and the second vacuum tank is connected to a process water conveying pipeline.

[0010] The present invention also proposes a water-saving and high-salt process for a vacuum belt conveyor, which is carried out using the water-saving and high-salt device for the vacuum belt conveyor as described above, and the process is as follows: The waste liquid to be treated from the gypsum cyclone station enters the first vacuum tank of the vacuum belt conveyor. The slurry from the first vacuum tank first passes through the first steam-water separator, and then a part of it is discharged to the clarified water tank. After the liquid in the clarified water tank is clarified, the upper part of the clear liquid enters the clean water tank, and the bottom mud enters the original desulfurization reuse water system. A part of the liquid entering the clean water tank passes through the booster water pump to the desulfurization wastewater zero discharge system, and is concentrated and evaporated to remove high salt, and the other part is used as sealing water and lubricating water for the front half of the vacuum belt conveyor; The filtrate from the second vacuum tank of the vacuum belt conveyor first passes through the second steam-water separator, and the liquid phase is discharged into the filtrate water tank. The liquid inside the filtrate water tank flows back to the original desulfurization reuse water system; The gas phases of the first steam-water separator and the second steam-water separator are discharged into the atmosphere through the action of a vacuum pump and a filter; The vacuum pump is connected to a process water delivery pipeline, and the liquid water in the filter is discharged into a flushing water tank. The liquid entering the flushing water tank is divided into two branches. One part is used as sealing water and lubricating water for the rear half of the vacuum belt conveyor through the flushing water pump, and the other part of the liquid flows back to the original desulfurization reuse water system.

[0011] Furthermore, the waste liquid to be treated is subjected to the action of a vacuum belt conveyor (in turn, it passes through a high salt concentration water system and a low salt concentration water system) to obtain a filter cake with a moisture content not higher than 10%, and the filter cake enters a gypsum bin; the solid content of the waste liquid to be treated from the gypsum cyclone station is 40% to 50%.

[0012] Compared with the prior art, the present invention reduces the consumption of process water and clean water of the vacuum belt conveyor by implementing a high-salt system and a low-salt system, thereby achieving the goal of water saving. At the same time, the filtrate water of the high-salt system enters the desulfurization wastewater zero discharge system for further concentration and evaporation of the high salt, thereby reducing the processing flow of evaporation and concentration, reducing the amount of evaporation and concentration, and thus reducing the energy consumption of the desulfurization wastewater zero discharge system. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the process structure of the vacuum belt conveyor dehydration system of the present invention; In the figure: 1. First vacuum tank; 2. Second vacuum tank; 3. First steam-water separator; 4. Second steam-water separator; 5. Clarifying water tank; 6. Clean water tank; 7. Booster water pump; 8. Desulfurization wastewater zero discharge system; 9. Desulfurization reuse water system; 10. Filtrate water tank; 11. Vacuum pump; 12. Filter; 13. Flushing water tank; 14. Flushing water pump; 15. Gypsum silo. DETAILED DESCRIPTION

[0014] To make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described in detail below. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other implementation methods obtained by ordinary technicians in this field without creative work belong to the scope of protection of the present invention.

[0015] Attached Figure 1 The vacuum belt conveyor dehydration flow chart of this embodiment is shown. This embodiment includes: a vacuum belt conveyor, a first vacuum tank 1, a first steam-water separator 3, a clarified water tank 5, a clean water tank 6, a booster water pump 7, a second vacuum tank 2, a second steam-water separator 4, a filtrate water tank 10, a vacuum pump 11, a filter 12, a flushing water tank 13, a flushing water pump 14, a gypsum bin 15, etc. The vacuum belt conveyor has a first vacuum tank 1 and a second vacuum tank 2 inside, which are arranged at the front section and the rear section of the vacuum belt conveyor respectively.

[0016] like Figure 1As shown, the solid content of the waste liquid from the gypsum cyclone station is 40% to 50%. The filter cake with a moisture content of no more than 10% is obtained through the action of the vacuum belt conveyor, and the filter cake enters the gypsum bin 15. The slurry coming out of the first vacuum tank 1 of the vacuum belt conveyor first passes through the first steam-water separator 3, and a part of it is lowered to the clarified water tank 5. After the liquid in the clarified water tank 5 is clarified, the upper part of the clear liquid enters the clean water tank 6, and the bottom mud enters the original desulfurization reuse water system 9. A part of the liquid entering the clean water tank 6 passes through the booster pump 7 to the desulfurization wastewater zero discharge system 8, and is concentrated and evaporated to produce high salt, and the other part is used as sealing water and lubricating water for the front half of the vacuum belt conveyor.

[0017] The filtrate coming out of the second vacuum tank 2 of the vacuum belt conveyor first passes through the second steam-water separator 4, and the liquid phase part is discharged into the filtrate water tank 10. The liquid in the filtrate water tank 10 is returned to the original desulfurization reuse water system 9. The gas phases of the first steam-water separator 3 and the second steam-water separator 4 are discharged into the atmosphere through the action of the vacuum pump 11 and the filter 12, and the liquid flows into the flushing water tank 13 by gravity. A part of the liquid entering the flushing water tank 13 is used as sealing water and lubricating water for the second half of the vacuum belt conveyor through the flushing water pump 14, and the other part of the liquid is returned to the original desulfurization reuse water system 9.

[0018] The lubricating water and sealing water of the front half of the vacuum belt conveyor of the present invention adopt high-salt clarified wastewater, which reduces the use of process water to a certain extent, and the lubricating water and sealing water of the rear half of the vacuum belt conveyor adopt low-salt flushing water, which reduces the use of process water to a certain extent. In addition, using high-salt clarified wastewater as liquid of the desulfurization wastewater zero discharge system 8 reduces the processing flow of evaporation and concentration to a certain extent, reduces the amount of evaporation and concentration, and reduces energy consumption.

[0019] In summary, the present invention divides the vacuum belt conveyor into functional divisions, with a high-salt concentration water system being implemented in the front section and a low-salt concentration water system being implemented in the back section; the clarified filtrate is used as part of the lubrication water and sealing water of the vacuum belt conveyor, thereby reducing the process water and clean water consumption of the vacuum belt conveyor and achieving the goal of water conservation; at the same time, the filtrate water of the high-salt system enters the desulfurization wastewater zero discharge system 8 for further concentration and evaporation of the high salt, thereby reducing the energy consumption of the desulfurization wastewater zero discharge system 8.

[0020] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A water-saving high-salt device for a vacuum belt conveyor, characterized in that: The invention comprises a high-salt concentration water system and a low-salt concentration water system. The vacuum tank inside the vacuum belt conveyor is divided into a first vacuum tank (1) and a second vacuum tank (2). The high-salt concentration water system comprises the first vacuum tank (1), a first steam-water separator (3), a clarified water tank (5), a clean water tank (6) and a booster water pump (7); the low-salt concentration water system comprises a second vacuum tank (2), a second steam-water separator (4), a filtrate water tank (10), a flushing water tank (13) and a flushing water pump (14).

2. A water-saving and high-salt device for a vacuum belt conveyor according to claim 1, characterized in that: The filtrate outlet of the first vacuum tank (1) is connected to the inlet of the first steam-water separator (3), the liquid phase outlet of the first steam-water separator (3) is connected to the inlet of the clarified water tank (5), the clear liquid outlet of the clarified water tank (5) is connected to the inlet of the clear water tank (6), the sludge outlet of the clarified water tank (5) is connected to the desulfurization reuse water system (9), and the outlet of the clear water tank (6) is connected to the booster water pump (7) and then divided into two branches, one branch is connected to the desulfurization wastewater zero discharge system (8), and the other branch is connected to the vacuum belt conveyor in the front half.

3. A water-saving and high-salt device for a vacuum belt conveyor according to claim 2, characterized in that: The filtrate outlet of the second vacuum tank (2) is connected to the inlet of the second steam-water separator (4), the liquid phase outlet of the second steam-water separator (4) is connected to the inlet of the filtrate water tank (10), and the outlet of the filtrate water tank (10) is connected to the desulfurization reuse water system (9).

4. A water-saving and high-salt device for a vacuum belt conveyor according to claim 3, characterized in that: The gas phase outlets of the first steam-water separator (3) and the second steam-water separator (4) are connected to each other and are then connected to a vacuum pump (11) and a filter (12) in sequence; the gas phase outlet of the filter (12) is connected to the atmosphere; and the vacuum pump (11) is connected to a process water delivery pipeline.

5. A water-saving and high-salt device for a vacuum belt conveyor according to claim 4, characterized in that: The liquid phase outlet of the filter (12) is connected to the inlet of the flushing water tank (13), and the outlet of the flushing water tank (13) is divided into two branches, one branch is connected to the desulfurization recycling water system (9), and the other branch is connected to the flushing water pump (14) and then connected to the vacuum belt conveyor in the rear half.

6. The water-saving and high-salt device of a vacuum belt conveyor according to claim 5, characterized in that: The first vacuum tank (1) is connected to a gypsum cyclone station to convey waste liquid to be treated, and the second vacuum tank (2) is connected to a process water conveying pipeline.

7. A water-saving and high-salt process for a vacuum belt conveyor, using the water-saving and high-salt device for a vacuum belt conveyor as claimed in claim 6, characterized in that: The process is as follows: The waste liquid to be treated from the gypsum cyclone station enters the first vacuum tank (1) of the vacuum belt conveyor. The slurry from the first vacuum tank (1) first passes through the first steam-water separator (3), and then a part of it is discharged into the clarified water tank (5). After the liquid in the clarified water tank (5) is clarified, the upper part of the clear liquid enters the clean water tank (6), and the bottom mud enters the original desulfurization reuse water system (9). A part of the liquid entering the clean water tank (6) passes through the booster pump (7) to the desulfurization wastewater zero discharge system (8), where it is concentrated and evaporated to remove high salt, and the other part is used as sealing water and lubricating water for the front half of the vacuum belt conveyor; The filtrate from the second vacuum tank (2) of the vacuum belt conveyor first passes through the second steam-water separator (4), and the liquid phase is discharged into the filtrate water tank (10). The liquid inside the filtrate water tank (10) flows back to the original desulfurization reuse water system (9).

8. The water-saving and high-salt process of a vacuum belt conveyor according to claim 7, characterized in that: The gas phases of the first steam-water separator (3) and the second steam-water separator (4) are discharged into the atmosphere through the action of a vacuum pump (11) and a filter (12).

9. The water-saving and high-salt process of a vacuum belt conveyor according to claim 8, characterized in that: The vacuum pump (11) is connected to a process water delivery pipeline, and the liquid phase water in the filter (12) is discharged into the flushing water tank (13). The liquid entering the flushing water tank (13) is divided into two branches, one part of which is used as sealing water and lubricating water for the rear half of the vacuum belt conveyor through the flushing water pump (14), and the other part of the liquid is returned to the original desulfurization reuse water system (9).

10. The water-saving and high-salt process of a vacuum belt conveyor according to claim 7, characterized in that: The waste liquid to be treated is passed through a vacuum belt conveyor to obtain a filter cake with a moisture content of no more than 10%, and the filter cake enters a gypsum bin (15); the solid content of the waste liquid to be treated from the gypsum cyclone station is 40% to 50%.

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