CN111803981A - A kind of high-salt, high-viscosity and easy-scaling material-liquid deep concentration evaporator and method - Google Patents

Abstract

The invention discloses a high-salt, high-viscosity and fouling-prone material liquid deep concentration evaporator and a method, which are composed of a shell, a heating plate, a central shaft, a rotary scraper, a driving motor, a bracket, a head and a support. The heating plate is a hollow disk-shaped structure. The lower part of the heating plate is provided with an inverted U-shaped notch. The heating plate is embedded in the bracket inside the casing. The rotary scraper is installed on the central axis and rotates with the central axis. between the heating plates. The present invention operates in the mode of mechanical scraping, and the rotating scraper can clean the surface dirt, crystals or solid attachments of the heating plate in time, and the evaporator does not have the problem of scaling and clogging. The invention can realize high concentration rate evaporation of the material liquid, has the characteristics of large evaporation heat transfer area, high production capacity, less supporting process equipment, etc., and is especially suitable for all kinds of high-viscosity, salt-containing, easy-scaling and complex-component materials. deep evaporation of the liquid.

Description

A kind of high-salt, high-viscosity and easy-scaling material-liquid deep concentration evaporator and method

technical field

The invention relates to an evaporator, in particular to an evaporator suitable for deep concentration of high-salt, high-viscosity and easy-scaling material liquid, and belongs to the technical field of evaporation.

Background technique

In the evaporation field, there are a large number of feed liquids with high viscosity, high salt, and easy scaling, such as landfill leachate, MVR mother liquor, multi-effect evaporation residual liquid, etc. This kind of feed liquid has complex components, high salinity, and a large amount of calcium and magnesium ions. Conventional technologies often use traditional scraper evaporators, forced circulation evaporators or direct incineration to evaporate and concentrate the above-mentioned feed liquids. Because the heat exchange surface of the traditional ^scraper evaporator is only the inner wall of the equipment, the heat exchange area is small and the evaporation production capacity is low. When the forced circulation evaporator is used to treat the above-mentioned feed liquid, it is usually necessary to match the corresponding pretreatment process to reduce the calcium and magnesium content in the feed liquid, resulting in a long process flow of the evaporation system, high operating costs, and a long forced circulation evaporator. A large amount of scale layer will still be deposited on the surface of the heat exchange tube after time operation, which will not only increase the heat transfer resistance, but even cause the heat exchange tube to be blocked, affecting the normal operation of the system. The environmental burden and energy consumption of the incineration treatment method are relatively large, and the incinerator has serious high-temperature corrosion problems when processing the above-mentioned feed liquid.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a high-salt, high-viscosity, and fouling-prone feed liquid deep concentration evaporator and method for the deficiencies of the above-mentioned prior art.

A high-salt, high-viscosity, and fouling-prone material liquid deep concentration evaporator and method, characterized in that: the evaporator comprises a shell, a heating plate, a central shaft, a rotating scraper, a drive motor, a bracket, a head and a support;

The shell is a horizontal cylindrical structure, the top of the shell is provided with a secondary steam outlet, a feed port and a raw steam inlet, the bottom of the shell is provided with a discharge port and a condensate outlet, and the lower part of the shell is provided with a support ;

The head is installed on both sides of the evaporator shell, the head is provided with a shaft hole for installing the central shaft, and the sealing and bearing components of the central shaft are installed at the shaft hole; the driving motor is connected with the central shaft;

The bracket is a frame for supporting and fixing the heating plate, and the bracket is fixed inside the evaporator shell;

The heating plate is a hollow plate-shaped structure, the top of the heating plate is provided with a steam interface, and the bottom is provided with a condensate interface. A plurality of the heating plates are installed on the bracket at equal distances to form a heating plate group. The steam interface on the top of each heating plate connected with each other, and the bottom condensate interface is connected with each other;

The rotating scraper is installed on the central shaft and rotates with the central shaft for scraping off the dirt on the heating plate, and each rotating scraper is installed between the heating plates at intervals.

Preferably, the support is made of square steel, the width of the support is equal to the width of the heating plate, and the length is the same as the length of the evaporator cylinder. Greater than or equal to the width of the rotating scraper.

Preferably, the rotary scraper is of a paddle type structure, the number of blades of the rotary scraper is not less than two, the blades of the rotary scraper are arranged at equal distances in the circumferential direction, and the length of the rotary scraper is equal to the radius of the heating plate.

Preferably, the lower part of the heating plate is provided with an inverted U-shaped notch to facilitate installation, and the inside of the heating plate is provided with a guide support rib.

Preferably, a polytetrafluoroethylene plate is attached to the surface of the rotating scraper.

Preferably, the drive motor is a variable frequency motor.

The present invention also provides a working method of a high-salt, high-viscosity, and fouling-prone material-liquid deep-concentration evaporator. 1/2 place; turn on the raw steam required for evaporation, the raw steam enters each heating plate in parallel through the steam joint of the heating plate, and provides the required heat for the evaporation of the material liquid. After the condensate interface is collected, the condensate outlet of the casing is discharged to the evaporator; the drive motor is turned on, and the motor drives the rotary scraper on the central shaft to rotate circumferentially, and the scraper blade continuously brings the liquid to the surface of the heating plate, and the surface of the heating plate is The dirt, crystals or solids remaining after evaporation should be cleaned up in time to keep the heat exchange surface of the heating plate clean. The secondary steam generated by the evaporation of the material liquid is discharged from the evaporator through the secondary steam outlet of the shell, and the concentrated liquid after the evaporation of the material liquid is discharged from the material outlet.

Compared with the prior art, the beneficial effects of the present invention are:

Compared with the traditional scraper evaporator, the invention can significantly expand the heat transfer area of the evaporator. Under the same height and diameter, the heat transfer area of the evaporator of the invention can reach 10-20 times that of the traditional scraper evaporator. Significantly increases the evaporation capacity of the evaporator. Compared with the traditional forced circulation evaporator, the present invention adopts the mechanical scraping mode to operate, and the rotating scraper can clean the surface dirt, crystals or solid attachments of the heating plate in time. The high concentration ratio of the feed liquid is evaporated; the feed liquid is in a mixed flow state of Kuta flow and film flow on the surface of the heating plate, the evaporator has a high heat transfer coefficient, and the amount of evaporated water per unit area can reach 20~150kg/m ² ; In addition, The use of this evaporator does not require pretreatment such as decalcification and magnesium removal of the feed liquid, which can reduce the investment and operating costs of the supporting equipment of the evaporation system. The evaporator of the invention is especially suitable for the evaporation and concentration of various kinds of high-viscosity, salt-containing and fouling-prone feed liquids.

Description of drawings

Fig. 1 is the structural representation of a kind of high-salt, high-viscosity and easy-scaling material-liquid deep-concentration concentrated evaporator of the present invention

Figure 2 is a side view of the structure of a high-salt, high-viscosity, and easily fouling material-liquid deep-concentration evaporator structure of the present invention

Figure 3 is the outline drawing of the evaporator heating plate

Figure 4 is the outline drawing of the evaporator blade scraper

Figure 5 is the outline drawing of the evaporator heating plate bracket

In the figure, 1 is the shell, 2 is the heating plate, 3 is the central axis, 4 is the rotating scraper, 5 is the drive motor, 6 is the bracket, 7 is the head, 8 is the support, 11 is the secondary steam outlet, 12 It is the feed port, 13 is the raw steam inlet, 14 is the discharge port, 15 is the condensate outlet, 21 is the steam port, 22 is the condensate port, 23 is the guide support rib, and 31 is the seal and bearing assembly.

Detailed ways

The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The examples are only used to explain the present invention, but not to limit the scope of the present invention.

Example 1:

As shown in Figures 1 and 2, a high-salt, high-viscosity, and easy-to-scale liquid deep concentration evaporator includes a casing 1, a heating plate 2, a central shaft 3, a rotating scraper 4, a drive motor 5, a bracket 6, a seal Head 7, support 8. The shell 1 is a horizontal cylindrical structure with a diameter of 1800mm and a length of 6000m. The top of the shell is provided with a secondary steam outlet 11, a feed port 12 and a raw steam inlet 13, and the bottom of the shell is provided with a discharge Port 14 and condensate outlet 15, and a support 8 is installed at the lower part of the shell; as shown in Figure 3, the heating plate is a hollow disk-shaped structure, and the inside of the heating plate is provided with a guide support rib 23, and the total thickness of the heating plate is 20mm. The diameter of the disk surface is 1000mm, the lower part of the heating disk is provided with an inverted U-shaped notch, and the width of the notch is 200mm. The steam ports on the top of each heating disk are connected with each other, and the condensate ports at the bottom are connected with each other; The inlet is connected; the condensate interface on the far right of the heating plate group is blocked by a blind plate, and the condensate interface on the left is connected with the condensate outlet of the evaporator shell; as shown in Figure 4, the rotary scraper 4 is a four-blade The blade type structure, the rotating scraper is installed on the central axis 3 and rotates with the central axis. The rotating scraper is 495mm long, the scraper surface is 28mm wide, and the distance between adjacent rotating scrapers is 50mm; the diameter of the central axis 3 is 150mm; as shown in Figure 5 As shown in the figure, the bracket 6 is welded by 100-type square steel, and a heating plate embedding groove is opened along the length direction of the bracket, the groove width is 20mm, and the groove spacing is 30mm; The heat exchange area is about 200m ² ; the central axis of the rotating scraper (116 in total) is installed to the central position of the heating plate through the lower notch of the heating plate; the sealing head 7 is installed on both sides of the evaporator shell, and a shaft is provided on the sealing head The sealing and bearing assembly 31 of the central shaft is installed at the shaft hole; the drive motor 5 adopts a frequency conversion motor and is connected to the central shaft 3 .

The working method of this embodiment is as follows:

The material liquid treated in this example is landfill leachate, the material is fed into the evaporator through the feed port of the shell, and the liquid level is kept at 1/2 of the height of the heating plate; Through the steam joint of the heating plate, it enters into each heating plate in parallel to provide the required heat for the evaporation of the material liquid. The condensate after the heat release of the raw steam is collected by the condensate interface at the bottom of the heating plate, and then discharged from the evaporator through the condensate outlet of the shell. . Turn on the drive motor, the motor power is 50kW, the motor drives the rotary scraper on the central shaft to rotate circumferentially, the scraper blade continuously brings the material liquid to the surface of the heating plate, and removes the residual dirt, crystals or solids after the surface of the heating plate evaporates in time Clean up to keep the heat exchange surface of the heating plate clean. The secondary steam generated by the evaporation of the material liquid is discharged from the evaporator through the secondary steam outlet of the shell, and the concentrated liquid after the evaporation of the material liquid is discharged from the material outlet.

In this embodiment, the heat exchange area is 200m ² , the diameter of the equipment is 1800mm, the length is 6000mm, the evaporation temperature of landfill leachate is 100°C, the temperature of raw steam is 150°C, and the heat transfer temperature difference of the evaporator is 50°C. The evaporating water volume of the evaporator is 25~30m ³ /h.

The landfill leakage liquid has a high salinity and contains a large amount of calcium and magnesium ions. Conventional evaporators have serious problems of scaling and plugging. In this embodiment, the mechanical scraping method is adopted, and the rotating scraper can timely clean the surface dirt, crystals or solid attachments of the heating plate, and can realize the deep evaporation and concentration of the landfill leachate. It has the advantages of large evaporation capacity and continuous operation.

Comparative example 1:

In this comparative example, a conventional wiper evaporator with the same external dimensions as in the first embodiment is used to treat the same landfill leachate as in the first embodiment. The wiper evaporator has a diameter of 1800mm and a height of 6000mm. The heat exchange area of the evaporator is 34m ² . The raw steam temperature is 150°C, the landfill leachate evaporation temperature is 100°C, the heat transfer temperature difference is 50°C, and the evaporation water volume of the evaporator in this embodiment is 4-5 m ³ /h.

Under the conditions of the same external dimensions, the heat transfer area of the wiped-blade evaporator of this comparative example is only 17% of that of the first embodiment; under the conditions of the same operating parameters, the evaporation of this comparative example is only the first embodiment. 15%~20%.

Although the present invention has been described above with reference to the accompanying drawings, the present invention is not limited to the above-mentioned specific embodiments. The above-mentioned specific embodiments are only illustrative rather than restrictive. Under the inspiration of the invention, many modifications can be made without departing from the spirit of the present invention, which all belong to the protection scope of the present invention.

Claims (7)

1. a high-salt, high-viscosity, and easily fouling material-liquid deep-concentration evaporator, characterized in that: the evaporator comprises a casing, a heating plate, a central shaft, a rotary scraper, a drive motor, a support, a head and a support; The shell is a horizontal cylindrical structure, the top of the shell is provided with a secondary steam outlet, a feed port and a raw steam inlet, the bottom of the shell is provided with a discharge port and a condensate outlet, and the lower part of the shell is provided with a support ; The head is installed on both sides of the evaporator shell, the head is provided with a shaft hole for installing the central shaft, and the sealing and bearing components of the central shaft are installed at the shaft hole; the driving motor is connected with the central shaft; The bracket is a frame for supporting and fixing the heating plate, and the bracket is fixed inside the evaporator shell; The heating plate is a hollow plate-shaped structure, the top of the heating plate is provided with a steam interface, and the bottom is provided with a condensate interface. A plurality of the heating plates are installed on the bracket at equal distances to form a heating plate group. The steam interface on the top of each heating plate connected with each other, and the bottom condensate interface is connected with each other; The rotating scraper is installed on the central shaft and rotates with the central shaft for scraping off the dirt on the heating plate, and each rotating scraper is installed between the heating plates at intervals. 2. A kind of high-salt, high-viscosity and easy-scaling material-liquid deep concentration evaporator according to claim 1, characterized in that: the support is made of square steel, the width of the support is equal to the width of the heating plate, and the length is the same as that of the evaporator cylinder. The length of the body is equal, the beam of the bracket is provided with a number of equidistant gaps, the gap width is equal to the thickness of the heating plate, and the distance between the gaps is greater than or equal to the width of the rotating scraper. 3. A kind of high-salt, high-viscosity and easy-scaling material-liquid deep concentration evaporator according to claim 1, characterized in that: the rotary scraper is a paddle-type structure, and the number of blades of the rotary scraper is not less than two, The blades of the rotating scraper are arranged at equal distances in the circumferential direction, and the length of the rotating scraper is equal to the radius of the heating plate. 4. A high-salt, high-viscosity, and easily fouling material-liquid deep concentration evaporator according to claim 1, characterized in that: the lower part of the heating plate is provided with an inverted U-shaped notch, and the inside of the heating plate is provided with a diversion support rib plate. 5 . The deep concentration evaporator of high-salt, high-viscosity, and easily fouling feed liquid according to claim 1 , wherein a polytetrafluoroethylene plate is attached to the surface of the rotating scraper. 6 . 6. A high-salt, high-viscosity, and fouling-prone feed-liquid deep-concentration evaporator according to claim 1, wherein the drive motor is a frequency conversion motor. 7. A working method for a high-salt, high-viscosity, and easily fouling material-liquid deep-concentration evaporator, characterized in that: the material is fed into the evaporator through the feed port of the shell, and the liquid level is maintained at 1/3 of the height of the heating plate ~1/2 place; turn on the raw steam required for evaporation, and the raw steam enters into each heating plate in parallel through the steam joint of the heating plate to provide the required heat for the evaporation of the material liquid. After the condensate interface is collected, the condensate outlet of the casing is discharged from the evaporator; the drive motor is turned on, and the motor drives the rotating scraper on the central shaft to rotate circumferentially, and the scraper blade continuously brings the liquid to the surface of the heating plate, and the heating plate The residual dirt, crystals or solids after the surface is evaporated are cleaned up in time to keep the heat exchange surface of the heating plate clean. The secondary steam generated by the evaporation of the material liquid is discharged from the secondary steam outlet of the shell to the evaporator. After the material liquid evaporates The concentrated liquid is discharged from the discharge port.

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