CN110655132A - Gas-liquid direct contact type evaporation and condensation universal device - Google Patents

Abstract

The invention relates to a gas-liquid direct contact type evaporation and condensation universal device which comprises a box body, a heating porous plate, a circulating pump, a liquid level controller, a water inlet pump, related pipelines and valves. The device utilizes air as a gas-liquid contact carrier, and when dry and cold air is in contact with hot wastewater, water in the hot wastewater is taken away, so that the wastewater is evaporated and concentrated; when the hot humid air is contacted with the cooled condensed water, the hot humid air is cooled, and the moisture is condensed into cold water, so that the hot humid air is dehumidified into dry and cold air. Meanwhile, the heat exchange pipe is directly welded with the pore plate, and waste water and heating circulating water or cooling water exchange heat in the device, so that the use of an additional heat exchanger is reduced. In order to avoid the corrosion of high-concentration waste water to the heat exchange pipe and the porous plate, the technology of plating the plastic coating on the porous plate is adopted, so that the service life of the equipment is prolonged. On the other hand, a high-low liquid level device is arranged at the bottom of the device and is used for a water inlet/outlet pump to keep the liquid level inside the device balanced. The device has the advantages of simple equipment, short process flow, convenient control and easy maintenance, and realizes the clean and environment-friendly treatment of high-concentration wastewater.

Description

Gas-liquid direct contact type evaporation and condensation universal device

Technical Field

The invention relates to a gas-liquid direct contact evaporation concentration or condensation dehumidification treatment device, in particular to a general heat exchange device for improving the evaporation concentration efficiency of low-temperature high-concentration wastewater and cooling and dehumidifying hot humid air by using air, belonging to the technical field of environment-friendly, energy-saving and quantitative reduction treatment of high-concentration industrial wastewater difficult to treat.

Background

The chemical industries of pharmacy, printing and dyeing, papermaking and the like belong to high-pollution industries, and a large amount of sewage is generated every day. Although the amount of industrial wastewater generated by the enterprises every day is not large, COD and TDS ammonia nitrogen are high, the industrial wastewater belongs to wastewater which is difficult to treat and degrade, the traditional treatment and disposal technology is difficult to effectively discharge in a harmless manner, and huge harm and safety risk are brought to the environment.

At present, various processes are used for treating high-concentration industrial wastewater, and a pretreatment and concentration technology is generally adopted. Wherein, the membrane concentration treatment technology can improve the concentration of industrial wastewater pollutants, greatly reduce the total amount of sewage, has low operation cost and is comprehensively popularized. But in actual engineering. The concentration of pollutants after membrane concentration still can not meet the requirement of harmless high-temperature incineration, the concentrated sewage still contains more moisture, and the salinity in the sewage can not be crystallized, so that a large amount of energy is still consumed for harmless incineration reprocessing, and the cost is higher. Therefore, it is necessary to continue the reduction treatment of the high concentration wastewater after the membrane concentration.

The reduction of high-concentration wastewater after membrane treatment can be realized only by a thermal evaporation concentration process. In order to reduce the evaporation energy consumption, many thermal evaporation technologies make full use of the latent heat of the secondary steam evaporated to evaporate high-concentration wastewater, such as multiple-effect evaporation, steam recompression technology and the like.

Through actual engineering projects, market research and patent retrieval, the current multiple-effect evaporation and steam recompression technology is used for high-concentration wastewater reduction treatment, and several problems are difficult to effectively solve: 1) the high-concentration wastewater has high salt content and is in a high-temperature solution environment, so that the wastewater has strong corrosivity on metal containers, metal heat exchange tubes and the like, the safety risk is high, and the service life of equipment is short; 2) evaporation and condensation equipment is mostly made of metal materials, high-concentration wastewater is easy to scale on the metal surface or separate out in a metal heat exchange tube, so that the serious scaling problem or the pipeline blockage problem is caused, and the normal and continuous operation of a system is influenced; 3) the multiple-effect evaporation and mechanical compression re-evaporation process has complex equipment, high investment and low investment cost performance for low waste water amount.

In view of the above problems, low temperature evaporation techniques have been attracting attention in recent years because low temperature evaporation can use solar energy waste heat, can use plastic materials and air as a carrier to perform evaporation concentration, and thus some problems such as metal corrosion and scaling are solved. However, the core low-temperature evaporation equipment structure design of the low-temperature evaporation technology and the condensation and dehumidification of the evaporated hot moisture are still difficult in technology, the problems that the evaporation heat exchange efficiency is not high, an additional heat exchanger is used for heating, metal corrosion is easy to occur in the cooling and dehumidification of a metal surface cooler and the like exist, and the popularization and the application of the low-temperature evaporation technology are seriously influenced.

Generally, the existing multi-effect evaporation and mechanical recompression evaporation heat concentration technology adopting a metal heat exchanger has technical problems which are difficult to overcome in the field of high-concentration wastewater treatment, and a novel low-temperature evaporation technology needs to adopt a high-efficiency evaporation technology, a non-metal hot and humid air condensation heat exchanger and the like. Therefore, it is necessary to find a process equipment or a device which can not only overcome the difficult problem of metal corrosion and scaling, but also has higher evaporation efficiency, dehumidification performance and the like, and simultaneously can be well adapted to various water quantities, and the investment cost is low, thereby realizing the high-efficiency energy-saving environment-friendly treatment of high-concentration wastewater reduction.

Disclosure of Invention

The invention aims to provide a gas-liquid direct contact type universal device for evaporation and condensation, which is provided for solving the technical problem that the traditional evaporation process is difficult to effectively treat industrial wastewater difficult to degrade and solves the problems of corrosion and scaling in the existing high-concentration wastewater evaporation heat concentration process, low-temperature evaporation efficiency, corrosion of a condensation dehumidification metal heat exchanger and the like.

The invention provides a gas-liquid direct contact type evaporation and condensation universal device which comprises a box body, a porous plate, a circulating liquid feeding device, a liquid return channel, a liquid level testing sensor, a liquid inlet and outlet device, a relevant auxiliary pipeline, a valve and a control system.

Wherein, the outer part of the box body shell 1-1 is wrapped with a heat preservation layer, the lower part is provided with an air inlet 1-2, the middle part is arranged with a porous plate at the lower part, the upper part is provided with an air outlet 1-3, and the bottom is in a contraction shape and is used for collecting and draining liquid. The solution return channel on the porous plate is hermetically connected with the porous plate through a partition plate 4-1, and a gap is reserved between the solution return channel and the side surface and the bottom of the box body 1-1, so that the upper part of the porous plate is communicated with the bottom of the box body 1-1, and the partition plate 4-1 is immersed below the solution level 5-3 to form a solution return channel 4-2. The perforated plate is hermetically connected with the baffle plate 4-1, and other side edges are hermetically fixed with the box body.

The porous plate is composed of a base plate 2-1, liquid collecting pipes 2-4 fixed on two sides of the base plate 2-1 and a plurality of heat exchange pipes 2-5, wherein a plurality of air holes 2-6 communicated up and down are formed in the base plate 2-1, the heat exchange pipes 2-5 are communicated with the liquid collecting pipes 2-4, the liquid collecting pipes 2-4 are provided with liquid inlet connectors 2-2 and liquid outlet connectors 2-3, the liquid inlet connectors 2-2 and the liquid outlet connectors 2-3 extend out of openings in the side face of a box body, and gaps are sealed.

The bottom of the box body 1-1 is connected with a pipeline 3-3, a valve 3-2 and a solution pump 3-1, according to the flowing direction of the solution, the solution enters the pipeline 3-3 and the valve 3-2 in sequence and is sent to the box body by the solution pump 3-1, and the position of the inlet of the box body is higher than the height position of the porous plate. In addition, the bottom of the box body 1 is also connected with a pipeline 6-3, a valve 6-2 and a solution pump 6-1, according to the flowing direction of the solution, the solution enters the pipeline 6-3 from a pipe orifice 6-4 in sequence when the evaporation function is realized, and is sent to the box body through the valve 6-2 by the solution pump 6-1, and the solution enters the pipeline 6-3 and the valve 6-2 in sequence when the condensation dehumidification function is realized, and is sent to the pipe orifice by the solution pump 6-1 to be discharged out of the box body.

The liquid containing part at the bottom of the box body is provided with a high liquid level sensor 5-1 and a low liquid level sensor 5-2. When the device realizes the evaporation function, when the low liquid level sensor 5-2 detects the liquid level, the solution pump 6-1 is started to pump the solution until the high liquid level sensor 5-2 detects the liquid level and the solution pump 6-1 is closed; when the device realizes the condensation dehumidification function, when the high liquid level sensor 5-1 detects the liquid level, the solution pump 6-1 is started to discharge the solution until the low liquid level sensor 5-1 detects the liquid level and the solution pump 6-1 is closed.

The working process of the invention is as follows:

according to the air flow process, air is blown from an air inlet 1-2 of the box body, passes through air holes 2-6 of the porous plate under the action of air pressure, and directly contacts with a solution on the porous plate for heat exchange, when the evaporation function is realized, dry and cold air and hot solution heat exchange become hot and wet air to take away solution moisture, when the condensation dehumidification function is realized, the hot and wet air and cold solution heat exchange become dry and cold air to lose moisture, an outlet 1-3 at the top of the box body is discharged, and the box body 1-1 is wrapped with a heat insulation material to effectively reduce the heat energy loss of the system.

According to the solution circulation process, the solution contained at the bottom of the box body 1-1 enters a pipeline 3-3, is sent to a porous plate in the box body through the pipeline 3-3 by a solution pump 3-1 through a valve 3-2, and flows back to the bottom of the box body 1-1 to be mixed with the solution under the action of a channel 4-2 formed by a partition plate 4-1 after being directly contacted with gas and liquid and exchanging heat with a heat exchange tube 2-5 on the porous plate.

According to the process of controlling the amount of the solution at the bottom of the tank body, when the device realizes an evaporation function, the low liquid level sensor 5-2 detects the liquid level, the controller starts the solution pump 6-1, external solution enters the tank body through the inlet 6-4, the pipeline 6-3 and the valve 6-2 until the high liquid level sensor 5-2 detects the liquid level 5-3, and the controller closes the solution pump 6-1; when the device realizes the condensation dehumidification function, the high liquid level sensor 5-1 detects the liquid level 5-3, and the solution pump 6-1 is started; the condensed water is discharged from an outlet 6-4 through a pipeline 6-3 and a valve 6-2 until a low liquid level sensor 5-1 detects a liquid level 5-3, and a controller turns off a solution pump 6-1, so that the total amount of the bottom solution is stable.

According to the circulation heat exchange process of external heating fluid or cooling fluid, external liquid enters from the porous plate liquid inlet connecting port 2-2 and enters the heat exchange tube 2-5 through the liquid collecting tube 2-4 in a distributed mode, the heat exchange tube 2-5 and the substrate 2-1 exchange heat with circulating solution through the tube wall and the substrate under the action of heat conduction, and fluid after heat exchange flows back to the liquid collecting tube 2-4 on the other side and flows out from the liquid outlet connecting port 2-3.

From the overall system, this gas-liquid direct contact evaporation condensation universal device both can realize high enriched waste water low temperature evaporation concentration minimizing, can realize hot humid air condensation dehumidification again, and the commonality is strong. Meanwhile, air is used as a water vapor carrier and directly exchanges heat with a low-temperature solution, so that the problems of equipment corrosion and scaling are reduced or even avoided, organic matter evaporation is effectively reduced, and the technical problem of the traditional evaporator and condensation heat exchanger in the aspect of high-concentration wastewater concentration is effectively solved. Moreover, a high-temperature steam heat source can be used, and low-temperature heat sources such as solar energy, flue gas waste heat and the like can be utilized, so that the operating energy consumption cost is reduced.

Compared with the existing widely used high-concentration waste water evaporation or evaporation hot vapor cooling equipment process or equipment, the gas-liquid direct contact type evaporation and condensation universal device provided by the invention has the characteristics and advantages that:

(1) the gas-liquid direct contact type evaporation and condensation universal device can evaporate solution and cool and dehumidify, can effectively reduce the manufacturing and installation processes of the whole process equipment as a universal device, and reduces the production cost of the system process

(2) This gas-liquid direct contact evaporation condensation universal device utilizes the air as evaporating the steam carrier, and air and high enriched waste water direct contact, evaporating temperature are low, have reduced even avoided equipment corrosion and scale deposit problem.

(3) This gas-liquid direct contact evaporation condensation universal device, heat exchange tube and bubble driven solution heat exchange efficiency are high on the perforated plate, reduce external solution cooling or heat transfer system that heaies up, can effectively utilize the low temperature heat source, accord with energy-conserving, the requirement of environmental protection.

(4) The gas-liquid direct contact type evaporation and condensation universal device adopts a low-temperature process, can be processed by adopting a plastic material, has less electromechanical equipment, high automatic control reliability and convenient whole processing, installation and maintenance.

(5) The gas-liquid direct contact type evaporation and condensation universal device has the advantages that air and solution contact heat exchange is realized, the temperature of the solution is adjustable, the device is suitable for industrial sewage with various concentrations and various components during evaporation, the waste heat of condensate can be recycled during condensation and dehumidification, the universality of the device is very strong, the energy is saved, the environment is protected, and the device has a wide application prospect.

Drawings

FIG. 1 is a schematic view of the overall structure of a gas-liquid direct contact type evaporation and condensation universal device.

Reference numbers in the figures: the device comprises a box body 1-1, an air inlet 1-2, an air outlet 1-3, a porous plate substrate 2-1, a liquid inlet connector 2-2, a liquid outlet connector 2-3, a solution pump 3-1, a valve 3-2, a pipeline 3-3, a partition plate 4-1, a solution backflow channel 4-2, a high liquid level sensor 5-1, a low liquid level sensor 5-2, a liquid level 5-3, a solution pump 6-1, a valve 6-2, a pipeline 6-3 and a liquid inlet and outlet pipe opening 6-4.

FIG. 2 is a schematic view showing the structure of the perforated plate of FIG. 1 according to the present invention

Reference numbers in the figures: the device comprises a porous plate substrate 2-1, a liquid inlet connector 2-2, a liquid outlet connector 2-3, a liquid collecting pipe 2-4, a heat exchange pipe 2-5 and air holes 2-6.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings 1 and 2, and the specific examples of the technical solutions of the present invention.

The evaporation function is realized according to a general device:

and dry and cold air is blown from the air inlet 1-2 of the box body, passes through the air holes 2-6 of the porous plate under the action of air pressure, is directly contacted with hot solution on the porous plate for heat exchange, and is changed into hot and humid air which is discharged from the air outlet 1-3 at the top of the box body 1-1.

The bottom of the box body 1-1 is filled with solution, the solution enters a pipeline 3-3, the solution is sent to a porous plate in the box body through the pipeline 3-3 by a solution pump 3-1 through a valve 3-2, although the solution is in direct contact with dry air for heat exchange and is evaporated moisture to dissipate heat, the solution is heated by a heat exchange tube 2-5 on the porous plate and a substrate 2-1 on the porous plate at the same time, so that a certain temperature is maintained, and the solution which cannot be contained in the porous plate flows back to the bottom of the box body 1-1 through a channel 4-2 formed by a partition plate 4-1 to be mixed with the.

As the water in the hot solution is taken out of the device by the dry and cold air, the solution at the bottom of the box body is continuously reduced, the low liquid level sensor 5-2 detects the liquid level, the controller starts the solution pump 6-1, the external solution enters the box body through the inlet 6-4, the pipeline 6-3 and the valve 6-2 until the high liquid level sensor 5-2 detects the liquid level 5-3, the controller closes the solution pump 6-1, and the evaporated solution is replenished.

External heating fluid, such as steam or hot water, enters from the porous plate liquid inlet connecting port 2-2, is distributed to enter the heat exchange tube 2-5 through the liquid collecting tube 2-4, the heat exchange tube 2-5 and the substrate 2-1 heat the solution through the tube wall and the substrate under the action of heat conduction, and the fluid after heat exchange and cooling flows back to the liquid collecting tube 2-4 at the other side and flows out from the liquid outlet connecting port 2-3.

Realize the condensation dehumidification function according to the device:

hot and humid air is blown in from the air inlet 1-2 of the box body, passes through the air holes 2-6 of the porous plate under the action of air pressure, directly contacts with a condensation solution on the porous plate for heat exchange, and is changed into cold and dry air which is discharged from the air outlet 1-3 at the top of the box body 1-1.

The bottom of the box body 1-1 is filled with condensed solution to enter a pipeline 3-3, the condensed solution is sent to a porous plate inside the box body through the pipeline 3-3 by a solution pump 3-1 through a valve 3-2, the condensed solution is in direct contact with hot and humid air for heat exchange, heat in the hot and humid air is absorbed and heated, and the heated condensed solution is cooled by a heat exchange tube 2-5 on the porous plate and a substrate 2-1 on the porous plate simultaneously, so that the temperature is kept constant, and the solution which cannot be contained on the porous plate flows back to the bottom of the box body 1-1 to be mixed with the condensed solution through a channel 4-2 formed by a partition plate 4.

As the condensed solution absorbs moisture in hot and humid air, the solution at the bottom of the box body is continuously increased, when the high liquid level sensor 5-1 detects the liquid level 5-3, the solution pump 6-1 is started, the condensed solution is discharged from the outlet 6-4 through the pipeline 6-3 and the valve 6-2 until the low liquid level sensor 5-1 detects the liquid level 5-3, and the controller closes the solution pump 6-1, so that the total amount of the condensed solution at the bottom is stable.

External cooling fluid, such as cooling circulating water, enters from the porous plate liquid inlet connecting port 2-2, is distributed to enter the heat exchange tube 2-5 through the liquid collecting tube 2-4, the heat exchange tube 2-5 and the substrate 2-1 cool a condensate solution through the tube wall and the substrate under the action of heat conduction, and the heated fluid flows back to the liquid collecting tube 2-4 on the other side and flows out from the liquid outlet connecting port 2-3.

In general, the box body 1-1 is wrapped with heat insulation materials, so that the heat energy loss of the system can be effectively reduced.

Claims (9)

1. A gas-liquid direct contact type evaporation and condensation universal device is characterized by comprising a box body, a porous plate, a circulating liquid feeding device, a liquid return channel, a liquid level testing sensor, a liquid inlet and outlet device, a relevant auxiliary pipeline, a valve and a control system.

2. The gas-liquid direct contact type evaporation and condensation universal device according to claim 1, characterized in that the outer shell of the box body 1-1 is wrapped with a heat insulation layer, the lower part is provided with an inlet 1-2, the upper part is provided with an air outlet 1-3, and the bottom is in a contraction shape for collecting and discharging liquid.

3. The universal device for vapor-liquid direct contact type evaporative condensation as claimed in claim 1, wherein the perforated plate is composed of a base plate 2-1, two side liquid collecting pipes 2-4 fixed on the base plate 2-1, and a plurality of heat exchange pipes 2-5, wherein the base plate 2-1 is provided with a plurality of air holes 2-6 communicated up and down, the heat exchange pipes 2-5 are communicated with the liquid collecting pipes 2-4, and the liquid collecting pipes 2-4 are provided with liquid inlet connectors 2-2 and liquid outlet connectors 2-3.

4. The gas-liquid direct contact evaporation and condensation universal device according to claim 1, wherein the bottom of the box body 1 is connected with the pipeline 3-3, the valve 3-2 and the solution pump 3-1, the pipeline 3-3, the valve 3-2, the solution pump 3-1, the pipeline 3-3 are connected with the box body and the inlet position is higher than the height position of the porous plate according to the solution flowing direction.

5. The universal device for vapor-liquid direct contact evaporation and condensation as claimed in claim 1, wherein the liquid return channel is hermetically connected with the perforated plate through a partition plate 4-1, a gap is reserved between the liquid return channel and the side surface and the bottom of the box body, the distance between the partition plate 4-1 and the bottom is less than the height of the liquid level by 5-3, so that the upper part of the perforated plate is communicated with the bottom of the box body to form a solution return channel 4-2.

6. A gas-liquid direct contact type evaporation and condensation universal device according to claim 1, claim 3 and claim 5, characterized in that the perforated plate is hermetically fixed with the box body at the other side except for being hermetically connected with the partition plate 4-1, the liquid inlet connecting port 2-2 and the liquid outlet connecting port 2-3 extend from the side opening of the box body, and the gap is sealed.

7. The universal device for vapor-liquid direct contact evaporation and condensation as claimed in claim 1, wherein the liquid containing part at the bottom of the tank body is provided with a high liquid level sensor 5-1 and a low liquid level sensor 5-2, and the liquid level in the tank body is between the heights of the liquid level sensor 5-1 and the low liquid level sensor 5-2.

8. The gas-liquid direct contact type evaporation and condensation universal device according to claim 1, characterized in that the bottom of the box body 1-1 is connected with the pipeline 6-3, the valve 6-2 and the solution pump 6-1, according to the flow direction of the solution, the solution enters the pipeline 6-3 from the pipe orifice 6-4 in sequence when the evaporation function is realized, the solution is sent to the box body through the valve 6-2 by the solution pump 6-1, and the solution enters the pipeline 6-3 and the valve 6-2 in sequence when the condensation and dehumidification function is realized, and is sent to the pipe orifice 6-4 by the solution pump 6-1 to be discharged out of the box body.

9. A gas-liquid direct contact evaporation and condensation universal device according to claim 1, claim 6 and claim 7, characterized in that when the device realizes the evaporation function, when the low liquid level sensor 5-2 detects the liquid level 5-3, the solution pump 6-1 is started to pump the solution, until the high liquid level sensor 5-2 detects the liquid level 5-3, the solution pump 6-1 is stopped; when the device realizes the condensation dehumidification function, when the high liquid level sensor 5-1 detects the liquid level 5-3, the solution pump 6-1 is started to discharge the solution until the low liquid level sensor 5-1 detects the liquid level 5-3, and the solution pump 6-1 is closed.

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