High-salt, high-COD and high-ammonia-nitrogen wastewater separation system

Abstract

The utility model relates to a high-salt high-COD (Chemical Oxygen Demand) high-ammonia nitrogen wastewater separation system which comprises an evaporation and drying all-in-one machine, a feeding tank, a feeding pump, a feeding preheater, a stripping tower, a concentrated solution cooler, a condensing tank and a discharging cooler, the feeding end of the feeding tank is connected with the evaporation and drying all-in-one machine, and the discharging end of the feeding tank is connected with the feeding preheater through the feeding pump; the feeding preheater is connected with the feeding end of the stripping tower, the stripping tower is connected with the concentrated solution cooler, the concentrated solution cooler is respectively connected with the condensation tank and the discharging cooler, and the condensation tank is connected with the stripping tower. Compared with traditional evaporation separation equipment, the high-salt, high-COD and high-ammonia-nitrogen wastewater separation system has the advantages that the separation effect of the stripping tower on low-boiling-point substances is higher than that of the traditional evaporation separation equipment, the steam and equipment operation pressure is lower, the energy consumption is lower, the equipment is simple, the investment is low, and the automation degree is high.

Description

Technical Field

[0001] The utility model relates to the technical field of wastewater separation systems, in particular to a high-salt, high-COD and high-ammonia-nitrogen wastewater separation system. Background Art

[0002] In the production process of some new materials, complex wastewater with high salt, high COD and high ammonia nitrogen will be generated, and it is necessary to remove salt, COD and ammonia nitrogen at the same time, and the treatment is difficult.

[0003] The existing wastewater separation systems of this kind are relatively complex and have high energy consumption. A large amount of heat will be generated during the production process, resulting in waste of resources. Summary of the Utility Model

[0004] Aiming at the deficiencies in the prior art, the utility model provides a high-salt, high-COD and high-ammonia-nitrogen wastewater separation system with simple equipment, low energy consumption and low cost.

[0005] The utility model is realized by the following technical solutions:

[0006] A high-salt, high-COD and high-ammonia-nitrogen wastewater separation system includes an evaporation and drying integrated machine, a feed tank, a feed pump, a feed preheater, a stripping tower, a concentrated liquid cooler, a condensate tank and a product cooler. The feed end of the feed tank is connected to the evaporation and drying integrated machine, and the discharge end of the feed tank is connected to the feed preheater through the feed pump. The feed preheater is connected to the feed end of the stripping tower. The stripping tower is connected to the concentrated liquid cooler. The concentrated liquid cooler is respectively connected to the condensate tank and the product cooler. The condensate tank is connected to the stripping tower.

[0007] In order to further improve the separation efficiency of COD and ammonia nitrogen, the top of the stripping tower has a first feed inlet, which is connected to the feed preheater. The bottom of the stripping tower has a first discharge outlet, and the first discharge outlet is connected to the first feed inlet through a circulation pump.

[0008] In order to facilitate the collection of water vapor with high COD and high ammonia nitrogen, the top of the stripping tower has a second discharge outlet, which is connected to the concentrated liquid cooler.

[0009] In order to maintain the stable operation of the system, the top of the stripping tower has a second feed inlet, which is connected to the condensate tank.

[0010] In order to carry out mass and energy exchange with the downward flowing material, the stripping tower is provided with a steam inlet.

[0011] In order to ensure the heat exchange effect, a multi-stage distributor is arranged in the stripping tower from top to bottom.

[0012] The stripping column of the present utility model is a device that utilizes the mass transfer process between liquid and gas to separate a mixed liquid into components of different purities through the difference in volatility of different components. Its working principle is as follows:

[0013] The mixed liquid (distilled water separated by the evaporation dryer) enters the bottom of the stripping column. Due to the difference in volatility of different components, the easily volatile components are partially evaporated into gas, while the less volatile components mainly remain in liquid form;

[0014] The gas rises to the top of the column, passes through the packing layer in the column, and makes full contact with the descending liquid, resulting in mass transfer between the gas and liquid phases;

[0015] Under the action of the packing layer, the easily volatile components are transferred from the liquid phase to the gas phase, and at the same time, the less volatile components are transferred from the gas phase to the liquid phase. This mass transfer between the gas and liquid phases is called rocking mass transfer;

[0016] The rocking mass transfer process causes the less volatile components in the liquid to gradually accumulate in the form of pure liquid, while the easily volatile components gradually decrease and disappear into the gas phase;

[0017] Finally, relatively pure gas of the easily volatile components will be collected at the top of the column, while relatively liquid rich in less volatile components will remain at the bottom of the column. According to needs, pure gas and pure liquid can be collected separately through collection pipes or valves at different positions;

[0018] In short, the stripping column uses the principle of rocking mass transfer to separate the mixed liquid into two components of pure gas and pure liquid, realizing the purification and separation of different components. This principle is widely used in the fields of fractionation and purification in the chemical industry.

[0019] The beneficial effects of the present utility model are: Compared with traditional evaporation separation equipment, the stripping column of this high-salt, high-COD, and high-ammonia-nitrogen wastewater separation system has a higher separation effect on low-boiling substances, lower steam and equipment operating pressures, lower energy consumption, simpler equipment, lower investment, and higher automation. Description of the Drawings

[0020] Figure 1 It is the schematic diagram of the high-salt, high-COD, and high-ammonia-nitrogen wastewater separation system of the present utility model;

[0021] Figure 2 It is the structural schematic diagram of the stripping column of the present utility model. Detailed Embodiments

[0022] The following elaborates on the preferred embodiments of the present utility model in conjunction with the drawings, so that the advantages and features of the present utility model can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present utility model.

[0023] AsFigure 1 A high-salt, high-COD, and high-ammonia-nitrogen wastewater separation system shown in the figure includes an evaporation and drying integrated machine, a feed tank 1, a feed pump 2, a feed preheater 3, a stripping tower 4, a concentrated liquid cooler 5, a condensate tank 6, and a discharge cooler 7. The feed end of the feed tank 1 is connected to the evaporation and drying integrated machine, and the discharge end of the feed tank 1 is connected to the feed end of the feed preheater 3 through the feed pump 2. The discharge end of the feed preheater 3 is connected to the feed end of the stripping tower 4. The stripping tower 4 is connected to the concentrated liquid cooler 5. The concentrated liquid cooler 5 is respectively connected to the condensate tank 6 and the discharge cooler 7. The condensate tank 6 is connected to the stripping tower 4 through a return pump 9.

[0024] Specifically, as shown in Figure 2 the figure, a multi-stage distributor 405 is arranged in the stripping tower 4 from top to bottom. The top of the stripping tower 4 has a first feed port 401, a second feed port 404, and a second discharge port 403. The first feed port 401 is connected to the discharge port of the feed preheater 3. The bottom of the stripping tower 4 has a first discharge port 402, and the first discharge port 402 is connected to the first feed port 401 through a circulation pump 8. The second discharge port 403 is connected to the feed port of the concentrated liquid cooler 5. The second feed port 404 is connected to the discharge port of the condensate tank 6 through a return pump 9. In addition, a steam inlet 406 is provided on the stripping tower.

[0025] The working principle of the present utility model is as follows:

[0026] The evaporation and drying integrated machine can separate and discharge the salts and macromolecular organic matters in the high-salt, high-COD, and high-ammonia-nitrogen solution, and distillate water with high COD and high ammonia nitrogen is separated during its operation. The feed tank 1 and the feed pump 2 are mainly used to temporarily store the distillate water coming from the evaporation and drying integrated machine and transport it to the stripping tower 4 for separation. The stripping tower 4 purifies the bottom material by continuously removing COD and ammonia nitrogen in the tower, and the reflux liquid at the top continuously circulates in the stripping tower 4. The PLC control system real-time detects the data of the sensors and automatically controls the start and stop of the pumps and valves through a preset program.

[0027] The distilled water containing high COD and high ammonia nitrogen evaporated from the evaporation and drying integrated machine is discharged from the outside of the evaporation and drying integrated machine to the feed tank 1 for temporary storage. After being conveyed by the feed pump 2 and heat-exchanged in the feed preheater 3, it enters the top of the stripping tower 4 through the first feed port 401; the material flows from the top of the tower to the bottom under the action of gravity. During this process, the steam introduced through the steam inlet 406 in the middle of the tower exchanges substances and heat with the downward-flowing material during the upward movement; the steam takes away the COD and ammonia nitrogen in the solution and flows to the top of the tower and is discharged through the second discharge port 403; the remaining part with low COD and low ammonia nitrogen flows downward to the bottom of the tower; the low-COD and low-ammonia nitrogen solution at the bottom of the tower returns to the stripping tower 4 through the circulation pump 8 and the first feed port 401 to reduce COD and ammonia nitrogen in a cycle. Among them, a part of the low-COD and low-ammonia nitrogen solution that reaches the treatment effect is discharged from the bypass, and recovers part of the heat with the feed preheater 3, and is discharged after being cooled by the discharge cooler 7; the high-COD and high-ammonia nitrogen water vapor evaporated from the top of the tower is condensed and cooled by the concentrated liquid cooler 5 and temporarily stored in the condensate tank 6. Part of it returns to the top of the tower through the return pump 9 and the second feed port 404 to maintain the stable operation of the system, and the remaining concentrated solution enriched with COD and ammonia nitrogen is discharged.

[0028] Compared with the existing evaporation separation equipment, the stripping tower of the present utility model has a higher separation effect on low-boiling substances than the traditional evaporation separation equipment. Its steam and equipment operating pressure are lower, the energy consumption is lower, the equipment is simple, the investment is low, and the degree of automation is high.

[0029] The above embodiments only represent several implementation modes of the present utility model, and the description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the utility model patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present utility model, several deformations and improvements can still be made, and these all belong to the protection scope of the present utility model.

Claims

1. A high-salt, high-COD, high-ammonia nitrogen wastewater separation system, characterized by: The invention comprises an evaporation-drying integrated machine, a feed tank, a feed pump, a feed preheater, a stripping tower, a concentrated liquid cooler, a condensing tank and a discharge cooler. The feed end of the feed tank is connected to the evaporation-drying integrated machine, the discharge end of the feed tank is connected to the feed preheater through the feed pump, the feed preheater is connected to the feed end of the stripping tower, the stripping tower is connected to the concentrated liquid cooler, the concentrated liquid cooler is respectively connected to the condensing tank and the discharge cooler, and the condensing tank is connected to the stripping tower.

2. The high-salt, high-COD, high-ammonia nitrogen wastewater separation system according to claim 1 is characterized by: The top of the stripping tower is provided with a first feed inlet, which is connected to a feed preheater. The bottom of the stripping tower is provided with a first discharge port, which is connected to the first feed inlet through a circulation pump.

3. The high-salt, high-COD, high-ammonia-nitrogen wastewater separation system according to claim 2 is characterized in that: The top of the stripping tower is provided with a second discharge port, and the second discharge port is connected to a concentrated liquid cooler.

4. The high-salt, high-COD, high-ammonia-nitrogen wastewater separation system according to claim 3 is characterized by: The top of the stripping tower is provided with a second feed inlet, and the second feed inlet is connected to the condensation tank.

5. The high-salt, high-COD, high-ammonia-nitrogen wastewater separation system according to claim 2 is characterized in that: The stripping tower is provided with a steam inlet.

6. The high-salt, high-COD, high-ammonia-nitrogen wastewater separation system according to claim 5 is characterized by: The stripping tower is provided with multiple stages of distributors from top to bottom.

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