JP2003236302A - Multiple-effect concentration system and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multiple-effect concentration system for concentrating a liquid efficiently. <P>SOLUTION: A condenser 9, a 3rd evaporation concentrator 5, a 3rd heat exchanger 2c, a 2nd evaporation concentrator 4, a 2nd heat exchanger 2b, a 1st evaporation concentrator 3 and a 1st heat exchanger 2a are evacuated by a vacuum apparatus 10 composed of a high pressure pump 10a and an ejector 10b. The inner pressure of the 1st evaporation concentrator 3 is set to a prescribed pressure by a pressure sensing/controlling apparatus V/S1 and a 5th solenoid valve V5 and the inner pressure of the 2nd evaporation concentrator 4 is set to a 2nd prescribed pressure lower than the 1st prescribed pressure and higher than a 3rd prescribed pressure by a 2nd pressure sensing/controlling apparatus V/S2. Waste water is quickly separated into steam and concentrated water in each evaporation concentrator by utilizing the pressure difference and the concentrated water is transferred without using a pump. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-effect concentrating system and method, and more specifically, a multi-effect concentrating method capable of obtaining a concentrate having a low water content and high-purity pure water from a liquid such as waste water or a pharmaceutical liquid. Concentration system and method.

[0002]

2. Description of the Related Art A conventional multi-effect concentrating system is provided with a plurality of atmospheric pressure evaporative concentrators, and each evaporative concentrator sequentially concentrates waste water or pharmaceuticals to form a concentrated liquid. The concentrated solution is transferred from the evaporative concentrator to the next evaporative concentrator using a pump, or is discharged to the tank storing the concentrated solution using the pump.

[0003]

However, in the conventional multiplex concentrating system, the heated wastewater or the supply liquid such as the pharmaceutical liquid flowing into each evaporative concentrator is subject to the atmospheric pressure in the evaporative concentrator. A large number of evaporative concentrators are required because it is not possible to efficiently and rapidly separate waste water, pharmaceutical liquids, or the like into steam and concentrated water in each evaporative concentrator. Accordingly, a large number of pumps are required to transfer the concentrated liquid concentrated in each evaporative concentrator. Therefore, the conventional multi-effect concentration system is expensive, and much cost is required for concentration.

The present invention was devised to solve the above-mentioned problems, and an object thereof is to provide a multi-effect concentrating system and method capable of concentrating a liquid rapidly and efficiently. .

[0005]

In order to achieve the above object, a multi-effect concentrating system and method according to the present invention, wherein each of the evaporative concentrators and the respective heat concentrators are used in concentrating a waste water, a pharmaceutical solution or the like by a multi-effect concentrating device. The evaporative concentrators and the heat exchangers are sequentially communicated with the exchanger to make the evaporative concentrators and the heat exchangers in different depressurized states, and then the heated feed liquid flowing into each evaporative concentrator is directed to the downstream side. Each evaporative concentrator receives a low pressure below atmospheric pressure as it goes.

According to a first aspect of the present invention, there is provided a multi-effect concentrating system for concentrating a liquid in multiple stages, the first heat exchanger heating the liquid, and the second heat exchanger arranged downstream of the first heat exchanger.
A first evaporative concentrator for separating a vapor of a component that is relatively easily vaporized from the heated liquid to obtain a low-order concentrated liquid;
A second heat exchanger arranged downstream of the first evaporative concentrator for heating the lower concentrated liquid using the steam;
A second evaporative concentrator disposed downstream of the heat exchanger for separating a vapor of a component that is relatively easily evaporated from the heated lower-order concentrated solution to obtain a higher-order concentrated solution; A condenser for liquefying the vapor disposed downstream of the condenser, a decompression device for decompressing the condenser, the first heat exchanger, the first evaporative concentrator, the second heat exchanger, and the Second
The first heat exchanger, the first evaporative concentrator, and the second evaporative concentrator so that the internal pressure decreases in the order of the condenser.
A heat exchanger and a pressure adjusting means for adjusting the internal pressure of the second evaporative condenser are provided.

The invention of claim 2 includes a waste liquid tank for containing a waste liquid, a heating steam pipe and a waste liquid pipe, each of which has at least first, second and third heat exchangers. A plurality of heat exchangers for heating the waste liquid and the waste liquid tank are arranged upstream of the first heat exchanger via a waste liquid inflow pipe having a first electronic opening / closing valve; A plurality of evaporative concentrators including at least first, second and third evaporative concentrators respectively arranged downstream of the plurality of heat exchangers;
A condenser in communication with the third evaporative concentrator, the first,
Heated waste liquid outlets of the second and third heat exchangers and the first and second
And the first, second and third heating waste liquid discharge pipes respectively connecting the heating waste liquid inlets of the third and third evaporative concentrators, the concentrated waste liquid outlets of the first and second evaporative concentrators and the second and third heats. The concentrated waste liquid inlet of the exchanger is connected to each other, and the first and second concentrated liquid transfer pipes provided with the second and third electronic on-off valves, the concentrated waste liquid outlet of the evaporative concentrator and the sludge tank are provided. A concentrated liquid transfer pipe connected to the ninth electronic on-off valve, an outer pipe inlet for steam of the second and third heat exchangers, and first and second
First and second evaporative vapor transfer pipes respectively connecting to vapor outlets of the evaporative concentrator, outlets of vapor outer pipes of the second and third heat exchangers, and first and second condensed water storage / condensation The first and second condensed water discharge pipes that respectively connect the upper ends of the tanks and the first and second condensed water storage / condensation tanks have a predetermined amount of condensed water stored in the first and second tanks. First and second level sensors for detecting whether or not the level has reached, respectively, and the first and second electronic control valves provided with fourth and sixth electronic control valves at the lower ends of the first and second tanks, respectively. 2 condensate discharge pipes are respectively connected, and the first condensate discharge pipe is connected to an upper end of the second condensed water storage / condensation tank, which is higher than the predetermined level and the first and second condensed waters. The first and second tanks are located at a position lower than the connection position with the discharge pipe. And first and second pressure control pipes respectively connected to the second and third evaporation vapor transfer pipes, and the first and second pressure control pipes include fifth and seventh electronic on-off valves, respectively. First and second pressure sensing / regulating devices provided between the fifth and seventh electronic on-off valves and the first and second tanks, respectively, the second pressure regulating pipe, and the third evaporation device. A vent line connected between a connection with a vapor transfer pipe and the seventh electronic on-off valve and having an eighth electronic on-off valve; and a concentrated liquid provided in the sludge tank and stored in the sludge tank. Level sensor for detecting the level of the liquid, a concentrated liquid discharge pipe having a tenth electronic on-off valve in communication with the lower end of the sludge tank and the atmosphere, and a liquid higher than the predetermined level and the concentrated liquid transfer. Connection position between pipe and sludge tank It is connected to the sludge tank at a lower position, and is connected between the connecting portion of the second pressure adjusting pipe and the third evaporative vapor transfer pipe and the seventh electronic opening / closing valve, and the eighth electronic opening / closing is provided on the way. A branch line equipped with a valve V8 and a pneumatic pump connected via a pneumatic line on the opposite side of the connection position of the sludge tank and the branch line with an eleventh electronic opening / closing valve in the middle. It is a multi-effect concentration system characterized by the following.

In the multi-effect concentrating system of the present invention, a condenser, a third evaporative concentrator, a third heat exchanger, a second evaporative concentrator, and a second heat exchanger are provided by a decompression device including a high pressure pump and an ejector. , The internal pressure of the first evaporative concentrator, the first heat exchanger, etc. is reduced, and the internal pressure of the first evaporative concentrator is set to a first predetermined pressure by a pressure sensing / regulating device and an electronic on-off valve. The pressure sensing / regulating device and other electronic opening / closing valve bring the internal pressure of the second evaporative concentrator to a second predetermined pressure lower than the first predetermined pressure and higher than the third predetermined pressure of the third evaporative concentrator. Set. As a result, the heating liquid flowing into each evaporative concentrator is subjected to a small pressure below the atmospheric pressure as it goes downstream, and is transferred downstream due to the pressure difference.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows the circuit of the multi-effect enrichment system of the present invention. The multi-effect concentrating system includes a waste liquid tank 1, an outer pipe for heating steam and an inner pipe for waste liquid, which are provided inside the first, second and third heat exchangers 2a, 2b, 2c for heating the waste liquid. 1, second and third evaporative concentrators 3, 4, 5, sludge tank 20, circulating water tank 30,
It has a condenser 9 and a pressure reducing means for reducing the pressure inside the condenser 9, that is, a vacuum device 10. The vacuum device 10 preferably includes a high pressure pump 10a and an ejector 10b.

The first, second and third evaporative concentrators 3, 4,
5, and the first, second and third heat exchangers 2a, 2b, 2
c is arranged in the order of the first heat exchanger 2a, the first evaporative condenser 3, the second heat exchanger 2b, the second evaporative condenser 4, the third heat exchanger 2c, the third evaporative condenser 5, The third evaporative condenser 5 communicates with the condenser 9 whose pressure has been reduced by the vacuum device 10 via the third evaporative vapor transfer pipe 112, and the waste liquid inner pipe of the first heat exchanger 2a has the first electron. The waste liquid inflow pipe 101 having the open / close valve V1 is connected to the waste liquid tank 1 by the control of the first electronic open / close valve V1.

The first, second and third heat exchangers 2a, 2b,
2c is a first, second and third heated waste liquid discharge pipe 102,
Through 105 and 110, they are connected to the first, second and third evaporative concentrators 3, 4, and 5, respectively. Therefore, the heated waste liquid is discharged into the first, second and third heat exchangers 2a, 2
From the waste liquid outlets b, 2c, through the first, second and third heated waste liquid discharge pipes 102, 105, 110, the first, second
And to the heating waste liquid inlets of the third evaporative concentrators 3, 4, and 5. The first and second evaporative concentrators 3 and 4 are the second and third
The second and third heat exchangers 2 are passed through the first and second concentrated liquid transfer pipes 104 and 109 equipped with the electronic opening / closing valves V2 and V3.
b, 2c. Therefore, the concentrated waste liquid is discharged from the waste liquid outlets of the first and second evaporative concentrators 3 and 4 into the first and second concentrated liquid transfer pipes 104 and 109 having the second and third electronic on-off valves V2 and V3. Through the second and third
It is supplied to the waste liquid inlets of the heat exchangers 2b and 2c.

The concentrated waste liquid outlet of the evaporative condenser 5 is connected to the upper end of the sludge tank 20 via a concentrated liquid transfer pipe 113 having a ninth electronic opening / closing valve V9. The steam outer pipe inlets of the second and third heat exchangers 2b and 2c are the first and second evaporative concentrators 3 and 4 which are arranged immediately upstream, and the steam outlets and the first and second evaporative vapor transfer pipes 103, 108 communicate with each other.

First, second and third evaporative concentrators 3, 4, 5
First, second and third connected to the inner space of the lower end of the
Each of the heating waste liquid discharge pipes 102, 105, 110 is
As shown in FIG. 2, the ring chamber 336 has a shape along the outer periphery of the lower ends of the first, second and third evaporative concentrators 3, 4, 5 and is located between the wall 332 and the ring wall 334. It is tangentially open to the side.

The outlet of the steam outer pipe of the second heat exchanger 2b is connected to the upper end of the first condensed water storage / condensation tank 201 via the first condensed water discharge pipe 107. First condensed water storage /
The condensation tank 201 is equipped with a first level sensor LS1 for sensing the level of condensed water stored in the tank 201, and the first condensed water discharge pipe 402 having a fourth electronic control valve V4 at the lower end of the tank 201. Are connected. When the first level sensor LS1 senses that the condensed water is stored in the tank 201 to a predetermined level, the condensed water stored in the tank 201 is discharged via the first condensed water discharge pipe 402. , The fourth electronic control valve V4 is controlled.

The first condensed water storage / condensation tank 201 is higher than the predetermined level and the first condensed water discharge pipe 107.
Is connected to the first pressure adjusting pipe 401 at a position lower than the connection position between the tank 201 and the tank 201. The first pressure adjusting pipe 401 is connected in the middle of the second evaporative vapor transfer pipe 108,
It may be directly connected to the second evaporative concentrator 4.

The pressure control pipe 401 has a fifth electronic opening / closing valve V5.
Is equipped with a fifth electronic on-off valve V5 and a tank 201.
In between, a first pressure sensing / regulating device V / S1 is provided. Here, the first pressure sensing / regulating device V / S1 controls the pressure of the first evaporative concentrator 3 to be a first predetermined pressure higher than the pressure of the second evaporative concentrator 4.

The first pressure sensing / regulating device V / S1 includes a first condensed water storage / condensation tank 201, a first condensed water discharge pipe 107, a steam outer pipe of the second heat exchanger 2b, which communicate with each other. First evaporative vapor transfer pipe 103 and first evaporative concentrator 3
Measure the internal pressure of. When the internal pressure is lower than the first predetermined pressure, the first condensed water storage / condensation tank 201 is ventilated to the outside to increase the pressure. The fourth electronic waste closing valve V4 is opened when the pressure detected by the first pressure sensing / regulating device V / S1 is higher than the first predetermined pressure, and
The second evaporative vapor transfer pipe 108 of the second evaporative condenser 4 whose pressure is set lower than that of the evaporative condenser 3 and the first condensed water storage /
The condensation tank 201 is connected to reduce the pressure.

The outlet of the outer pipe for steam of the third heat exchanger 2c is connected to the upper end of the second condensed water storage / condensation tank 202 via the second condensed water discharge pipe 111, and the second condensed water storage A first condensed water discharge pipe 402 for discharging the condensed water stored in the first condensed water storage / condensation tank 201 is connected to the upper end of the / condensation tank 202.

The second condensed water storage / condensation tank 202 detects the level of the condensed water stored in the tank 202.
It has a level sensor LS2. When the second level sensor LS2 detects that the condensed water is stored in the tank 202 up to a predetermined level, the tank 20
The condensed water stored in the tank 202 is connected via the second condensed water discharge pipe 404 which connects the lower end of 2 and the middle of the third vaporized vapor transfer pipe 112 and which is equipped with the sixth electronic on-off valve V6. The sixth electronic on-off valve V6 is controlled so as to discharge it to the condenser 9.

In the second condensed water storage / condensation tank 202,
The second condensed water discharge pipe 1 is higher than the predetermined level and
At a position lower than the connection position between 11 and the tank 201, the second
It is connected to the pressure control pipe 403. Second pressure control pipe 4
03 may be connected to the third vaporized vapor transfer pipe 112,
It may be directly connected to the third evaporative condenser 5.

The second pressure control pipe 403 is equipped with a seventh electronic opening / closing valve V7, and the seventh electronic opening / closing valve V7 and the tank 2 are provided.
Between 02, a second pressure sensing / regulating device V / S2 is provided. The second pressure sensing / regulating device V / S2 has a second predetermined pressure at which the pressure of the second evaporative condenser 4 is higher than the pressure of the third evaporative condenser 5 and lower than the pressure of the first evaporative condenser 3. Control to become.

The second pressure sensing / regulating device V / S2 is in communication with the second condensed water storage / condensation tank 202, second.
The internal pressures of the condensed water discharge pipe 111, the outer pipe of the third heat exchanger 2c, the second evaporation transfer pipe 108, and the second evaporation concentrator 4 are measured, and when the internal pressure is lower than the second predetermined pressure, Two
The condensed water storage / condensation tank 202 is ventilated to the outside to increase the pressure. The seventh electronic on-off valve V7 is opened when the pressure detected by the second pressure sensing / regulating device V / S2 is higher than the second predetermined pressure, and the pressure is set lower than the pressure of the second evaporative concentrator 4. Third of the third evaporative concentrator 5
The evaporative vapor transfer pipe 112 and the vapor second condensed water storage / condensation tank 202 are connected to each other to lower the pressure.

The sludge tank 20 is the sludge tank 20.
A third level sensor LS3 for detecting the level of the concentrated liquid stored therein is provided, and at the lower end of the sludge tank 20, a concentrated liquid discharge pipe 406 having a tenth electronic opening / closing valve V10 which is open to the atmosphere is provided. It is connected. When it is detected by the third level sensor LS3 that the condensed water is stored in the sludge tank 20 to a predetermined level, the concentrated liquid stored in the sludge tank 20 is discharged to the outside via the concentrated liquid discharge pipe 406. The tenth electronic on-off valve V10 is controlled so as to operate.

The sludge tank 20 is connected to the branch line 405 at a position higher than the predetermined level and lower than the connection position between the concentrated liquid transfer pipe 113 and the sludge tank 20. The branch line 405 is connected between the connecting portion between the second pressure adjusting pipe 403 and the third evaporative vapor transfer pipe 112 and the seventh electronic on-off valve V7, and is provided with the eighth electronic on-off valve V8 on the way. ing. Sludge tank 20 and branch line 4
A pneumatic line 407 is connected to the opposite side of the connection position with 05. The pneumatic line 407 communicates with the pneumatic pump 50 via the eleventh electronic on-off valve V11.

When the concentrated liquid is stored in the sludge tank 20 to the predetermined level, the eighth and ninth electronic on-off valves V8 and V9 are closed, and the tenth and eleventh electronic on-off valves V1.
When the pneumatic pump 50 is operated with 0 and V11 open, the concentrated liquid in the sludge tank 20 is forcibly discharged to the outside due to the pressure difference.

The vacuum device 10 circulates the circulating water in the circulating water tank 30 in the order of the circulating water tank 30, the high pressure pump 10a and the ejector 10b. The condenser 9 discharges the condensed water condensed in the condenser 9 as pure water into the circulating water tank 30 through the condensed water transfer pipe 114 that connects the ejector 10b and the steam pipe of the condenser 9 to the condenser 9 of the condenser 9. Decompress the steam tube.

Since the vapor pipe (not shown) provided in the condenser 9 in which the cooling water is circulated through the pipe for cooling water (not shown) is decompressed by the vacuum device 10, the third vaporized vapor transfer pipe The steam that has flowed into the steam pipe of the condenser 9 via 112 is liquefied in the condenser 9 and is circulated as condensed water via the condensed water transfer pipe 114 as a circulating water tank 3.
Released to zero.

The condensed water stored in the circulating water tank 30 after being filtered by this system is 97% to 9%.
8% pure water can also be discharged via the discharge line 115 and used for other purposes.

Next, a method for concentrating the waste liquid by the multi-effect concentrating system configured as described above will be described. First, the condenser 9, the third evaporative concentrator 5, and the third heat exchange are performed by the vacuum device 10 with all the electronic on-off valves V1 to V9 excluding the tenth and eleventh electronic on-off valves V10 and V11 opened. The pressure inside the vessel 2c, the second evaporative condenser 4, the second heat exchanger 2b, the first evaporative condenser 3 and the first heat exchanger 2a is reduced, and the first pressure sensing / regulating device V / S is also provided.
The first and fifth electronic on-off valves V5 set the internal pressure of the first evaporative condenser 3 to a first predetermined pressure, and the second pressure sensing / regulating device V / S2 and the seventh electronic on-off valve V7 provide the second evaporative concentration. The internal pressure of the vessel 4 is set to a second predetermined pressure that is lower than the first predetermined pressure but higher than the third predetermined pressure of the third evaporative concentrator 5. Here, the internal pressure of the third evaporative concentrator 5 is
Since the third evaporative concentrator 5 is arranged upstream of the first and second evaporative concentrators 3 and 4 (position close to the vacuum device 10),
It is lower than the internal pressure of the first and second evaporative concentrators 3 and 4. The third predetermined pressure of the third evaporative concentrator 5 is the vacuum device 10
Can be set by

The waste liquid stored in the waste liquid tank 1 flows into the inner pipe of the first heat exchanger 2a in the depressurized state via the waste liquid inflow pipe 101 and is heated to a predetermined temperature. Next, the waste liquid heated by the inner pipe of the first heat exchanger 2a flows into the first evaporative condenser 3 in the reduced pressure state via the first waste liquid discharge pipe 102. Due to the connection mode between the first waste liquid discharge pipe 102 and the first evaporative condenser 3, the waste liquid forms a rotary flow in the first evaporative condenser 3, and is centrifugally separated to be separated into vapor and waste liquid.
It becomes the next concentrated liquid. In this embodiment, the steam is water vapor composed of water that is relatively easily vaporized, and the primary concentrated liquid contains components that are relatively difficult to vaporize.

The primary concentrated liquid is transferred to the inner pipe of the second heat exchanger 2b in a depressurized state via the first concentrated liquid transfer pipe 104,
The vapor centrifugally separated in the first evaporative condenser 3 is passed through the first evaporative vapor transfer tube 103 so as to heat the primary concentrated liquid flowing into the inner tube of the second heat exchanger 2b in a reduced pressure state. It is supplied to the outer tube of the 2 heat exchanger 2b. Therefore, the primary concentrated liquid is heated to the predetermined temperature in the second heat exchanger 2b.

The primary concentrated liquid heated to a predetermined temperature in the inner tube of the second heat exchanger 2b flows into the second evaporative concentrator 4 via the second waste liquid discharge pipe 105, and the second heat exchanger. The steam that has flowed into the outer pipe of 2b and has heated the primary concentrated liquid is passed through the first condensed water discharge pipe 107 to the first condensed water storage / condensation tank 201.
Is released to.

Here, the condensed water discharged to the first condensed water storage / condensation tank 201 via the first condensed water discharge pipe 107 is stored up to a predetermined level in the first condensed water storage / condensation tank 201. Then, the fourth electronic development valve V4 is opened and transferred to the second condensed water storage / condensation tank 202 via the first condensed water discharge pipe 402.

The primary concentrated liquid flowing into the second evaporative condenser 4 via the second waste liquid discharge pipe 105 is again centrifuged,
Separated into steam and waste liquid to form a secondary concentrated liquid. The secondary concentrated liquid that has been centrifugally separated by the second evaporative condenser 4 is transferred to the inner pipe of the third heat exchanger 2c in the depressurized state via the second concentrated liquid transfer pipe 109, and then the second evaporative concentrator 4 is used. Centrifuged steam is
The secondary concentrated liquid that has flowed into the inner pipe of the third heat exchanger 2c in the depressurized state is discharged to the outer pipe of the third heat exchanger 2c via the second evaporative vapor transfer pipe 108 so as to be heated. Therefore,
The secondary concentrate is heated to a predetermined temperature.

The secondary concentrated liquid heated to a predetermined temperature in the inner pipe of the third heat exchanger 2c flows into the third evaporative condenser 5 through the third waste liquid discharge pipe 110, and the third heat exchange. Bowl 2c
The steam that has flowed into the outer pipe of the above and heated the secondary concentrated liquid is discharged to the second condensed water storage / condensation tank 202 via the second condensed water discharge pipe 111.

Here, the condensed water discharged to the second condensed water storage / condensation tank 202 via the second vapor discharge pipe 111 is condensed with the condensed water introduced via the first condensed water discharge pipe 402. They are combined and stored in the second condensed water storage / condensation tank 202. When the amount of condensed water in the second condensed water storage / condensation tank 202 reaches a predetermined level, the sixth electronic opening / closing valve V
6 is opened, and the condensed water is discharged to the condenser 9 via the second condensed water discharge pipe 402.

The secondary concentrated liquid that has flowed into the third evaporative condenser 5 via the third waste liquid discharge pipe 110 is centrifugally separated and separated into steam and waste liquid to become a third concentrated liquid. Third evaporative concentrator 5
The steam that has been centrifugally separated in (3) is flown into the condenser 9 in the depressurized state via the third evaporative vapor transfer pipe 112, becomes pure condensed water, and sequentially passes through the condensed water transfer pipe 114 and the ejector 10b. Is discharged to the circulating water tank 30. The third concentrated solution centrifugally separated by the third evaporative concentrator 5 is discharged to the sludge tank 20 via the third concentrated solution transfer pipe 113. When the third concentrated liquid is stored in the sludge tank 20 to a predetermined level, the eighth and ninth electronic on-off valves V8 and V9 are closed, and the tenth and eleventh electronic on-off valves V19 and V11.
Is released, and the pneumatic pump 50 is operated to discharge the concentrated liquid to the outside via the concentrated liquid discharge pipe 406.
In this embodiment, the electronic on-off valves V1 to V8 and the pressure sensing / regulating devices V / S1 and V / S2 constitute pressure adjusting means.

According to the invention, a multistage evaporative concentrator 3,
Low pressure is maintained at 4 and 5 downstream. The liquid is heated by the multistage heat exchangers 2a, 2b, 2c, and is sequentially concentrated by separating the vapors in the multistage evaporative concentrators 3, 4, 5. By utilizing the pressure difference, the concentrated liquid and the vapor are transferred to the heat exchanger in the next stage without using a transfer pump. Further, since the concentrated liquid is heated by the separated steam, the heat is effectively used and is efficient. By the multi-stage concentration, components that are relatively easily evaporated in the mixed liquid such as waste water and pharmaceutical liquid are separated from the liquid, and substances that are relatively hard to be evaporated remaining in the liquid are sequentially concentrated. For example, when the substance that is relatively hard to evaporate is an unnecessary substance such as an impurity, the component that is relatively easy to evaporate can be recovered as a high-purity liquid.

In the above description of the embodiments, the present system and method have been described for waste liquids, but the present system and method can be applied to other liquids such as pharmaceutical liquids instead of waste liquids.

[0040]

According to the present invention, in the case of concentrating waste water or pharmaceutical liquid with a multi-effect concentrator, each evaporative concentrator and each heat exchanger are sequentially connected to each other by a depressurizing means. After making the heat exchanger and each heat-reducing state different from each other, the heated feed liquid that flows into each evaporative concentrator receives a lower pressure from each evaporative concentrator as it goes to the downstream side. In addition, each evaporative concentrator can quickly separate waste water or pharmaceutical liquid into steam and concentrated water. Therefore, not only the number of evaporative concentrators is reduced, but also a pump for transferring the concentrated liquid concentrated in each evaporative concentrator is not required. As a result, the system equipment is inexpensive,
Concentration costs are also reduced.

[Brief description of drawings]

FIG. 1 is a schematic diagram of the circuit of a multi-effect enrichment system according to the present invention.

2 is a cross-sectional view of the lower end of the evaporative concentrator of the multi-effect concentrating system of FIG.

[Explanation of symbols]

1 ... Waste liquid tank, 2a, 2b, 2c ... Heat exchanger, 3,
4, 5 ... Evaporative concentrator, 9 ... Condenser, 10 ... Decompression device, 2
0 ... Sludge tank, 30 ... Circulating water tank, 50 ... Pneumatic pump, 103, 108, 112 ... Evaporative vapor transfer pipe, V
1, V2, V3, V4, V5, V6, V7, V8, V
9, V10 ... Electronic on-off valve as pressure adjusting means, 10
2, 105, 110 ... Waste liquid discharge pipes, 104, 109, 1
13 ... Concentrated liquid transfer pipe, 107, 111 ... Condensed water discharge pipe,
402, 404 ... Condensate discharge pipe, 401, 403 ... Pressure adjusting pipe, V / S1, V / S2 ... Pressure sensing / adjusting device as pressure adjusting means, 405 ... Aeration line, 406 ... Concentrated liquid discharge pipe, 407 ... Pneumatic line

Claims (6)

[Claims] 1. A multi-effect concentrating system for concentrating a liquid in multiple stages, comprising: a first heat exchanger for heating the liquid; and a heated liquid arranged downstream of the first heat exchanger. A first evaporative concentrator for separating a vapor of a component that is relatively easily vaporized to obtain a low-order concentrated liquid; and a first evaporative concentrator arranged downstream of the first evaporative concentrator to use the vapor to separate the low-order concentrated liquid. A second heat exchanger for heating, and a second heat exchanger arranged downstream of the second heat exchanger for separating a vapor of a component that is relatively easily evaporated from the heated low-order concentrate to obtain a higher-order concentrate A second evaporative condenser, a condenser arranged downstream of the second evaporative condenser for liquefying the vapor, a decompression device for decompressing the condenser, the first heat exchanger, the first The evaporative concentrator, the second heat exchanger, the second evaporative concentrator, and the condenser are arranged in this order. A multi-effect concentrating system comprising: the first heat exchanger, the first evaporative concentrator, the second heat exchanger, and pressure adjusting means for adjusting the internal pressure of the second evaporative concentrator so that the pressure becomes low. . 2. A multi-effect concentrating system, comprising a waste liquid tank for containing a waste liquid, each having a heating steam pipe and a waste liquid pipe therein, and at least first, second and third heat exchanges. A plurality of heat exchangers for heating the waste liquid including a container and the waste liquid tank are arranged upstream of the first heat exchanger via a waste liquid inflow pipe having a first electronic opening / closing valve. A plurality of evaporative concentrators including at least first, second, and third evaporative concentrators respectively arranged downstream of the plurality of heat exchangers; and a condenser in communication with the third evaporative concentrator. , First, second and third heating waste liquid discharges connecting the heating waste liquid outlets of the first, second and third heat exchangers and the heating waste liquid inlets of the first, second and third evaporative concentrators, respectively. A pipe, concentrated waste liquid outlets of the first and second evaporative concentrators, and the second
And the concentrated waste liquid inlet of the third heat exchanger, respectively,
And first and second equipped with second and third electronic on-off valves
A concentrated liquid transfer pipe, a concentrated liquid waste outlet of the evaporative concentrator and a sludge tank are connected, and a concentrated liquid transfer pipe having a ninth electronic opening / closing valve, and steam outer pipe inlets of the second and third heat exchangers And first and second evaporative vapor transfer tubes that connect the vapor outlets of the first and second evaporative concentrators, respectively, and the outlets of the outer vapor tubes of the second and third heat exchangers and the first and second evaporative vapor transfer tubes. First and second condensed water discharge pipes respectively connecting the upper ends of the second condensed water storage / condensation tanks, and the first and second condensed water storage / condensation tanks are stored in the first and second tanks. First and second level sensors for detecting whether or not the amount of condensed water has reached a predetermined level, respectively, and fourth and sixth electronic control valves are provided at the lower ends of the first and second tanks, respectively. First and second condensed water discharge pipes are respectively connected, and the first condensed water discharge pipe The pipe is connected to the upper end of the second condensed water storage / condensation tank, and is located at a position higher than the predetermined level and lower than the connection position with the first and second condensed water discharge pipes. First and second pressure adjusting pipes respectively connected to the two tanks and respectively connected to the second and third evaporative vapor transfer pipes, and the first and second pressure adjusting pipes are fifth and seventh electronic switching devices, respectively. First and second pressure sensing / regulating devices provided between the fifth and seventh electronic on-off valves and the first and second tanks, respectively, and the second pressure regulating pipe and the second The third electronic vapor on / off valve is connected to the third vaporized vapor transfer pipe, and the eighth electronic on-off valve is connected.
A ventilation line having an electronic opening / closing valve, a third level sensor provided in the sludge tank for detecting the level of the concentrated liquid stored in the sludge tank, a lower end of the sludge tank and the atmosphere, A concentrated liquid discharge pipe provided with an electronic opening / closing valve, connected to the sludge tank at a position higher than the predetermined level and lower than a connection position between the concentrated liquid transfer pipe and the sludge tank, and the second A branch line that is connected between the connection portion between the pressure control pipe and the third evaporative vapor transfer pipe and the seventh electronic on-off valve, and has an eighth electronic on-off valve in the middle; and a sludge tank and the branch line. A multi-effect concentrating system, comprising: a pneumatic pump connected to the opposite side of the connection position via a pneumatic line provided with an eleventh electronic on-off valve on the way. 3. The first and second pressure adjusting tubes are the second
And the third waste liquid discharge pipes connected to the inner space portions at the lower ends of the first, second and third evaporative concentrators, respectively. A ring chamber having a shape along the outer circumference of the first, second and third evaporative concentrators, and defined between the outer wall and the inner wall of the first, second and third evaporative concentrators, The steam pipe of the condenser is connected to a condensed water transfer pipe connected to an ejector that communicates with a circulating water tank. Multi-effect concentration system. 4. A method for concentrating waste liquid using the multi-effect concentrating system according to claim 1, wherein the first to ninth electronic on-off valves are opened, The pressure reducing device reduces the pressure inside the condenser, the third evaporative condenser, the third heat exchanger, the second evaporative condenser, the second heat exchanger, the first evaporative condenser and the first heat exchanger, The first pressure sensing / regulating device and the fifth electronic on-off valve set the internal pressure of the first evaporative condenser to a first predetermined pressure, and the second pressure sensing / regulating device and the seventh electronic on-off valve set the second evaporative concentration. Setting the internal pressure of the vessel to a second predetermined pressure lower than the first predetermined pressure and higher than the third predetermined pressure of the third evaporative concentrator, and reducing the waste liquid stored in the waste liquid tank. Is supplied to the inner pipe of the first heat exchanger via the waste liquid inflow pipe. And heating to a constant temperature, the waste liquid that has been heated in the inner pipe of the first heat exchanger is introduced into the first evaporator concentrator depressurized state via the first waste liquid discharge pipe,
A step of centrifuging into steam and a primary concentrate, and a step of centrifuging the primary concentrate in the first evaporative concentrator
The vapor transferred to the inner pipe of the second heat exchanger in the depressurized state via the concentrated liquid transfer pipe and centrifugally separated by the first evaporative condenser is passed through the first evaporative vapor transfer pipe to the second vapor. Heating the primary concentrate supplied to the outer pipe of the heat exchanger and flowing into the inner pipe of the second heat exchanger; and the primary concentrate heated in the inner pipe of the second heat exchanger. Is the second
Steam that flows into the second evaporative concentrator via the waste liquid discharge pipe and heats the primary concentrated liquid is discharged to the first condensed water storage / condensation tank via the first condensed water discharge pipe; , A step of centrifuging the primary concentrated liquid, which has flowed into the second evaporative concentrator via the second waste liquid discharge pipe, into a vapor and a secondary concentrated liquid again, and centrifugal separation in the second evaporative concentrator. Second concentrated liquid is second
The vapor transferred to the inner pipe of the third heat exchanger in the reduced pressure steam via the concentrated liquid transfer pipe and centrifugally separated by the second evaporative condenser is passed through the second evaporative steam transfer pipe to the first evaporative vapor transfer pipe. Heating the secondary concentrate supplied to the outer pipe of the third heat exchanger and flowing into the inner pipe of the third heat exchanger; and the secondary concentration heated by the inner pipe of the third heat exchanger. Liquid is third
A step in which the steam that has flowed into the third evaporative concentrator via the waste liquid discharge pipe and has heated the secondary concentrated liquid is discharged into the second condensed water storage / condensation tank via the second condensed water discharge pipe; A step of separating the secondary concentrated liquid flowing into the third evaporative concentrator via the third waste liquid discharge pipe into a vapor and a third concentrated liquid, and centrifuging in the third evaporative concentrator. The vapor flows into the depressurized vapor condenser via the third vaporization vapor transfer pipe and is liquefied into pure condensed water. The condensed water is circulated through the condensed water transfer pipe and the ejector sequentially to the circulating water tank. Discharged to the sludge tank through the third concentrated liquid transfer pipe, the third concentrated liquid being discharged to the sludge tank through the third concentrated liquid transfer pipe. Is set by the vacuum device, and the internal pressure of the third evaporative concentrator is 1 and multiple effect concentration method comprising the steps of: lower than the internal pressure of the second evaporator concentrator. 5. The first pressure sensing / regulating device includes a first condensed water storage / condensation tank, a first condensed water discharge pipe, a steam outer pipe of the second heat exchanger, and a first evaporation which are in communication with each other. The internal pressures of the vapor transfer pipe and the first evaporative concentrator 3 are measured, and when the measured internal pressure is lower than the first predetermined pressure, the first condensed water storage / condensation tank is increased to increase the pressure. Is vented to the outside, and the fourth electronic on-off valve has a lower pressure than the first evaporative concentrator so as to reduce the pressure detected by the first pressure sensing / regulating device when the pressure is higher than the first predetermined pressure. Second of the second evaporative concentrator of
Evaporative vapor transfer pipe and the first condensed water storage / condensation tank 20
A second pressure sensing / regulating device in communication with each other.
Condensed water storage / condensation tank, second condensed water discharge pipe, said third
When the internal pressures of the outer tube of the heat exchanger, the second evaporative transfer tube, and the second evaporative concentrator are measured and the internal pressure is lower than the second predetermined pressure, the second pressure is increased to increase the pressure.
The condensed water storage / condensation tank is ventilated to the outside, and the seventh electronic on-off valve is configured to reduce the pressure when the pressure detected by the second pressure sensing / regulating device is higher than the second predetermined pressure. The multi-effect concentrating method according to claim 4, wherein the third evaporative vapor transfer pipe of the third evaporative concentrator is connected to the second condensed water storage / condensation tank. 6. The eighth and ninth electronic on-off valves are closed and the tenth and eleventh electronic on-off valves are opened when the amount of the third concentrated liquid discharged to the sludge tank reaches a predetermined level. Operate the air pressure pump to remove 3 of the sludge tank.
Discharging the next concentrated liquid to the outside via the concentrated liquid discharge pipe, and the amount of condensed water discharged to the first condensed water storage / condensation tank via the first condensed water discharge pipe to a predetermined level. When it reaches, the step of opening the fourth electronic on-off valve and transferring it to the second condensed water storage / condensation tank via the first condensed water discharge pipe, and the second condensed water via the second vapor discharge pipe. When the total amount of the condensed water discharged to the storage / condensation tank and the condensed water flowing into the second condensed water storage / condensation tank via the first condensed water discharge pipe reaches a predetermined level, The step of opening the sixth electronic on-off valve to discharge the condensed water of the second condensed water storage / condensation tank to the condenser via the second condensed water discharge pipe, The multiplex according to claim 4. Utility concentration method.