Salt-containing wastewater crystallization and drying device

Abstract

The utility model discloses a salt-containing wastewater crystallization and drying device, which relates to the field of salt-containing wastewater crystallization and drying, and comprises a spiral airflow crystallization and drying device, a fan, a three-phase separator and a heat pump system, the spiral airflow crystallization drying device comprises an outer shell and a spiral body; the spiral body is rotationally connected into the outer shell and can rotate along the axis of the spiral body. The outer shell is communicated with a feed port, a discharge port, an air inlet and an air outlet; the feed port and the air inlet are positioned at one end of the spiral body, and the discharge port and the air outlet are positioned at the other end of the spiral body; the three-phase separator is communicated with the gas outlet and an inlet of the heat pump system; an outlet of the heat pump system is communicated with an inlet of the fan; an outlet of the fan is communicated with the air inlet; air holes are formed in the spiral body; the spiral body is also wrapped with a hydrophobic breathable semi-permeable membrane to cover the breathable holes; the salt-containing wastewater crystallization and drying device can efficiently realize crystallization and drying of salt-containing wastewater at low cost.

Description

Technical Field

[0001] The utility model belongs to the technical field of saline wastewater drying, and in particular relates to a saline wastewater crystallization drying device. Background Art

[0002] The full-scale treatment of saline wastewater is a process of reducing, stabilizing and detoxifying saline wastewater by conditioning, concentrating, crystallizing and drying or incinerating it. The drying of saline wastewater has become the most complex and costly part of the operation of saline wastewater treatment systems. It has the characteristics of high hardness and easy scaling, high viscosity and easy wall adhesion. The current conventional crystallization drying method is to use inter-wall heat exchange, such as drum dryers, paddle dryers, etc., which usually require supporting heating steam and cooling circulating water. Such equipment generally has serious scaling, poor sealing, small processing capacity, high energy consumption, high operation and maintenance costs, and is prone to secondary pollution to the surrounding environment during operation.

[0003] Prior art, such as the patent application with application number CN202110138729.5, discloses a process device for heat pump-driven carrier gas extraction of waste liquid with low evaporation energy consumption, high concentration efficiency and high safety, including a hazardous waste liquid circulation system, an extraction air circulation system, a heat pump system and a data acquisition system. This scheme is only suitable for the treatment of hazardous waste liquid without crystallization (without clogging the semipermeable membrane and pipeline), which is difficult to match the existing treatment status of saline wastewater, and the technical versatility is not ideal; for example, the patent application with application number CN201610229721.9 discloses an industrial liquid hazardous waste treatment system, which consists of three parts: an air circulation treatment microsystem, a waste liquid concentration treatment microsystem and a heat pump system circulation microsystem. This scheme does not take into account the drying of waste liquid, system scaling problems, and heat source air distribution uniformity problems, and has poor applicability for the drying effect of saline wastewater.

[0004] Therefore, how to achieve the crystallization and drying of the above-mentioned salt-containing waste liquid efficiently and at low cost has become an urgent problem to be solved in this field. Utility Model Content

[0005] The utility model aims at the deficiencies in the prior art and provides a salt-containing wastewater crystallization and drying device, which can realize the crystallization and drying of salt-containing wastewater with high efficiency and low cost.

[0006] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0007] A salt-containing wastewater crystallization and drying device comprises a spiral airflow crystallization and drying device, a fan, a three-phase separator and a heat pump system; the spiral airflow crystallization and drying device comprises an outer shell and a spiral body; the spiral body is rotatably connected in the outer shell and can rotate along its own axis; the outer shell is connected with a feed port, a discharge port, an air inlet and an air outlet; the feed port and the air inlet are located at one end of the spiral body, and the discharge port and the air outlet are located at the other end of the spiral body; the three-phase separator is connected with the air outlet and the inlet of the heat pump system; the outlet of the heat pump system is connected with the inlet of the fan; the outlet of the fan is connected with the air inlet; the spiral body is provided with air holes; the spiral body is also wrapped with a hydrophobic and breathable semi-permeable membrane to cover the air holes.

[0008] Optionally, the hydrophobic, breathable semipermeable membrane is made of a composite of one or more polymer materials such as polytetrafluoroethylene, polyethylene or polypropylene.

[0009] Optionally, the pore size of the hydrophobic breathable semipermeable membrane is Φ10-Φ50 nm; the pore size of the breathable pore is Φ1.5-Φ3 mm.

[0010] Optionally, the three-phase separator includes a cover tube, a wire mesh and a cyclone; the wire mesh and the cyclone are located inside the cover tube; the cover tube is in the shape of an inverted frustum, and the small diameter end is connected to the air outlet, and the large diameter end is connected to the inlet of the heat pump system; the cyclone is in the shape of an inverted cone; one end of the wire mesh is connected to the large diameter end of the cover tube, and the other end is connected to the large diameter end of the cyclone.

[0011] Optionally, the wire mesh is made of metal with a diameter of Φ0.05-Φ0.15 mm, and the pores through which the medium of the cyclone passes are 0.5-1.0 mm.

[0012] Optionally, the spiral airflow crystallization dryer further includes a vibration module and a rotation module; the rotation module is located outside the outer shell and is connected to the spiral body to drive the spiral body to rotate; the vibration module is connected to the spiral body.

[0013] Optionally, the cold medium of the heat pump system is refrigerant; the outlet temperature of the heat pump system is 45-80° C.; and the heat pump system is also connected to a condensate collector.

[0014] Optionally, a liquid distribution spray pipe is provided at the end of the feed port inserted into the outer shell; and the discharge port is connected to a crusher.

[0015] The beneficial effects of the utility model are:

[0016] A spiral body is arranged in the spiral airflow crystallization dryer, through which air holes are arranged and covered with a hydrophobic and breathable semipermeable membrane, so that the circulating hot air can achieve micro-nano-level uniform air distribution. The circulating hot air and the saline wastewater are in full contact on the surface of the semipermeable membrane, which increases the heat exchange efficiency and the liquid vaporization rate. At the same time, a three-phase separator is arranged at the air outlet of the spiral airflow crystallization dryer to achieve efficient separation of particles, entrained liquid foam and humid hot air. The heat pump system is used to recover part of the condensation heat. The production process is fully enclosed, without secondary pollution, and is energy-saving, environmentally friendly, safe and reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0018] Figure 2 It is an enlarged structural schematic diagram of the three-phase separator of the utility model.

[0019] Marked in the figure are: 1 is a spiral airflow crystallization dryer, 2 is a fan, 3 is a three-phase separator, 31 is a cover tube, 32 is a wire mesh, 33 is a cyclone, 4 is a heat pump system, 5 is a feed port, 6 is an air inlet, 7 is a liquid distribution spray pipe, 8 is a discharge port, 9 is an air outlet, 10 is a crusher, 11 is a condensate collector, 12 is a spiral body, 13 is an outer shell, 14 is a vibration module, and 15 is a rotation module. DETAILED DESCRIPTION

[0020] The utility model is described in detail below with reference to the accompanying drawings.

[0021] It should be noted that the terms such as "upper", "lower", "left", "right", "front", "back", etc. used in the utility model are only for the convenience of description and are not used to limit the scope of implementation of the utility model. Changes or adjustments in their relative relationships should be regarded as the scope of implementation of the utility model without substantially changing the technical content.

[0022] like Figure 1 As shown, a salt-containing wastewater crystallization and drying device is provided, including a spiral airflow crystallization dryer 1, a fan 2, a three-phase separator 3 and a heat pump system 4.

[0023] The spiral airflow crystallization dryer 1 includes an outer shell 13 and a spiral body 12; the spiral body 12 is rotatably connected in the outer shell 13 and can rotate along its own axis; specifically, the spiral airflow crystallization dryer 1 also includes a vibration module 14 and a rotation module 15; the rotation module 15 is located on the outside of the outer shell 13 and is connected to the spiral body 12. The rotation module 15 is a rotary motor, and the output shaft of the rotary motor is connected to the central axis of the spiral body 12. Of course, in some other embodiments, it can also be connected through a transmission device; the rotation module 15 can control the rotation frequency of the spiral body 12; the vibration module 14 can be a vibration motor, and the specific structure refers to the prior art. The vibration module 14 is connected to the spiral body 12, and the material form and discharge rate of the spiral airflow crystallization dryer 1 can be controlled by the vibration module 14. Specifically, the salt-containing wastewater can achieve uniform material distribution and control the flow rate to ensure its crystallization and drying effect after vibration.

[0024] The outer shell 13 is connected with a feed port 5, a discharge port 8, an air inlet 6 and an air outlet 9; the feed port 5 and the air inlet 6 are located at one end of the spiral body 12, and the discharge port 8 and the air outlet 9 are located at the other end of the spiral body 12; the feed port 5 and the air inlet 6 are located at the top of the outer shell 13, the discharge port 8 is located at the bottom of the outer shell 13, and the air outlet 9 is located at the top of the outer shell 13; the feed port 5 is used for the entry of salt-containing wastewater, and the discharge port 8 is used for discharging the material after crystallization and drying; the air inlet 6 is used for the entry of a drying heat source, and the dry hot air becomes saturated humid hot air after crystallization and drying, and is discharged from the air outlet 9 of the spiral airflow crystallization dryer 1.

[0025] The three-phase separator 3 is connected to the air outlet 9 and the inlet of the heat pump system 4; the outlet of the heat pump system 4 is connected to the inlet of the fan 2; the outlet of the fan 2 is connected to the air inlet 6; the spiral body 12 is provided with air holes; the spiral body 12 is also wrapped with a hydrophobic breathable semipermeable membrane to cover the air holes; the three-phase separator 3 and the heat pump system 4 are used to realize the circulation of the dry heat source, and the hydrophobic breathable semipermeable membrane is used to realize the micro-nano-level uniform distribution of hot air. After the hot air and the saline wastewater are fully in contact on the surface of the semipermeable membrane, the saline wastewater is instantly crystallized and dried. At the same time, the heat pump system 4 is used to realize the latent heat recovery of the condensation of the moist hot air. There is no need to separately equip the cooling circulating water and steam heat source, which saves energy and avoids secondary pollution to the external environment of the system, so as to achieve the purpose of low-energy consumption and efficient crystallization and drying of the saline wastewater.

[0026] The specific material and preparation method of the hydrophobic breathable semipermeable membrane can refer to the prior art. As an option, the hydrophobic breathable semipermeable membrane is made of a composite of one or more polymer materials such as polytetrafluoroethylene, polyethylene or polypropylene; the material of the hydrophobic breathable semipermeable membrane has low surface energy and does not allow water to wet the surface, and can also resist organic pollution and operate at a high temperature of 150°C; the membrane pore size of the hydrophobic breathable semipermeable membrane is Φ10~Φ50nm; the pore size of the air pores is Φ1.5~Φ3mm; after the saline wastewater enters the spiral airflow crystallization dryer 1, the heat source air is evenly distributed in a micro-nano manner through the hydrophobic breathable semipermeable membrane, and the heat source air is fully in contact with the saline wastewater on the surface of the semipermeable membrane, thereby increasing the heat exchange efficiency and the liquid vaporization rate.

[0027] like Figure 2 As shown, the three-phase separator 3 includes a cover tube 31, a wire mesh 32 and a cyclone 33; the wire mesh 32 and the cyclone 33 are located inside the cover tube 31; the cover tube 31 is in the shape of an inverted truncated cone, and the small diameter end is connected to the air outlet 9, and the large diameter end is connected to the inlet of the heat pump system 4; the cyclone 33 is in the shape of an inverted cone; one end of the wire mesh 32 is connected to the large diameter end of the cover tube 31, and the other end is connected to the large diameter end of the cyclone 33; the three-phase separator 3 is a gas, liquid and solid separation device, and its specific function In order to remove the particulate impurities and liquid foam entrained in the humid hot exhaust gas and obtain pure humid hot air; the wire mesh 32 is made of metal with a diameter of Φ0.05~Φ0.15 and is used to intercept the foam and droplets entrained in the humid hot air; the cyclone 33 adopts a spiral intermittent and uniform arrangement of a number of baffles to control the medium to pass through the pore size of 0.5-1.0mm, so that the particles entrained in the humid air enter the bottom of the three-phase separator 3 and return to the spiral airflow crystallization dryer 1, and the pure humid hot air enters the heat pump system 4.

[0028] After the hot and humid air discharged after three-phase separation is processed by the heat pump system 4, the hot and humid air is cooled, and the water vapor is condensed into water droplets and discharged from the air. The heat pump refrigerant recovers heat energy to achieve evaporation during the dehumidification process of the hot and humid air, and the redundant energy is dissipated to the outside of the system through heat exchange of the cooling circulating water system, ensuring the continuous and stable operation of the compressor; the refrigerant converted into steam after evaporation is converted into high-temperature refrigerant by compression of the compressor; the dry air after cooling is converted into higher temperature dry air through the recovered condensation heat to achieve energy recycling; the refrigerant of the heat pump is a refrigerant such as R134a or R142b, and the heat pump is also connected to a condensed water collector 11. The whole system is closed in design, hot air is recycled, no secondary pollution is caused to the outside, and the energy utilization rate is high. The outlet temperature of the heat pump system 4 is 45-80°C, so that the circulating hot air of 45-80°C is used as the drying heat source.

[0029] Furthermore, a liquid distribution spray pipe 7 is provided at the end of the feed port 5 inserted into the outer shell 13 ; and the discharge port 8 is connected to a crusher 10 .

[0030] When the utility model is in use, the salt-containing wastewater to be treated is transported to the feed port 5, and the salt-containing wastewater enters the outer shell 13 of the spiral airflow crystallization dryer 1 and is fully mixed with the outlet high-temperature drying heat source of the fan 2, so that the water-containing salt-containing wastewater is fully dried, and gas-solid separation is achieved after being fully crystallized and dried in the spiral airflow crystallization dryer 1. After crystallization and drying, the solid is discharged from the system through the discharge port 8 at the bottom of the spiral airflow crystallization dryer 1, and the saturated wet air enters the three-phase separator 3;

[0031] After the saturated wet air passes through the three-phase separator 3 to remove particulate impurities and liquid foam, it enters the heat pump system 4 to separate the air and moisture in the wet and hot exhaust gas, and at the same time the heat pump system 4 recovers part of the condensation heat; the condensed hot air recovered by the heat pump system 4 reaches the dry air temperature and is sent back into the spiral airflow crystallization dryer 1 through the fan 2 as a dry heat source. The utility model adopts a fully enclosed design, and uses 45-80°C micro-nano-level dry hot air to achieve thorough crystallization and drying of water-containing and salt-containing wastewater. At the same time, a heat pump is used to realize partial condensation heat recovery, and there is no need to separately equip cooling circulating water and steam heat sources, which saves 30% energy compared with traditional drying equipment.

[0032] The above are only preferred implementations of the utility model. The protection scope of the utility model is not limited to the above embodiments. All technical solutions under the idea of ​​the utility model belong to the protection scope of the utility model. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the utility model should be regarded as the protection scope of the utility model.

Claims

1. A salt-containing wastewater crystallization and drying device, characterized in that: The invention comprises a spiral airflow crystallization dryer (1), a fan (2), a three-phase separator (3) and a heat pump system (4); the spiral airflow crystallization dryer (1) comprises an outer shell (13) and a spiral body (12); the spiral body (12) is rotatably connected in the outer shell (13) and can rotate along its own axis; the outer shell (13) is connected with a feed inlet (5), a feed outlet (8), an air inlet (6) and an air outlet (9); the feed inlet (5) and the air inlet (6) are located at the outer shell (13). The spiral body (12) is provided with an air outlet (8) and an air outlet (9) at one end thereof, and the spiral body (12) is provided with an air hole. The spiral body (12) is also wrapped with a hydrophobic and breathable semipermeable membrane to cover the air hole.

2. The salt-containing wastewater crystallization and drying device according to claim 1 is characterized in that: The hydrophobic and breathable semipermeable membrane is made of a composite of one or more polymer materials such as polytetrafluoroethylene, polyethylene or polypropylene.

3. The salt-containing wastewater crystallization and drying device according to claim 1 is characterized in that: The membrane pore size of the hydrophobic breathable semipermeable membrane is Φ10-Φ50nm; the pore size of the breathable pore is Φ1.5-Φ3mm.

4. The salt-containing wastewater crystallization and drying device according to claim 1 is characterized in that: The three-phase separator (3) comprises a cover tube (31), a wire mesh (32) and a cyclone (33); the wire mesh (32) and the cyclone (33) are located inside the cover tube (31); the cover tube (31) is in the shape of an inverted truncated cone, and the small-diameter end is connected to the air outlet (9), and the large-diameter end is connected to the inlet of the heat pump system (4); the cyclone (33) is in the shape of an inverted cone; one end of the wire mesh (32) is connected to the large-diameter end of the cover tube (31), and the other end is connected to the large-diameter end of the cyclone (33).

5. The salt-containing wastewater crystallization and drying device according to claim 4 is characterized in that: The wire mesh (32) is made of metal with a diameter of Φ0.05-Φ0.15 mm, and the pores for the medium to pass through the cyclone (33) are 0.5-1.0 mm.

6. The salt-containing wastewater crystallization and drying device according to claim 1 is characterized in that: The spiral airflow crystallization dryer (1) further comprises a vibration module (14) and a rotation module (15); the rotation module (15) is located outside the outer shell (13) and is connected to the spiral body (12) to drive the spiral body (12) to rotate; the vibration module (14) is connected to the spiral body (12).

7. The salt-containing wastewater crystallization and drying device according to claim 1 is characterized in that: The cold medium of the heat pump system (4) is a refrigerant; the outlet temperature of the heat pump system (4) is 45-80° C.; and the heat pump system (4) is also connected to a condensed water collector (11).

8. The salt-containing wastewater crystallization and drying device according to claim 1 is characterized in that: The end of the feed port (5) inserted into the outer shell (13) is provided with a liquid distribution spray pipe (7); the discharge port (8) is connected to a crusher (10).

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