CN1097559C - Vaporizing and concentration drying apparatus and method - Google Patents

Abstract

Vaporizing and concentration drying apparatus and method are disclosed. The apparatus and method prepare good quality of condensed water and save evaporation energy and are wide used in making contamined waste water become distilled water and in purification of the waste water and in concentration and drying of varieties of environmental polluting sludge. The apparatus and method recover and reuse the heating energy, which energy was applied to the vapor so as to heat the vapor to a high temperature and to remove the environmental polluting impurities, such as odor, B.O.D. and C.O.D. laden in the vapor, so that the apparatus and method remarkably save the cost for the heating energy. The apparatus saves the energy by 2 to 10 times in comparison with the conventional apparatus.

Description

Evaporation and concentration drying equipment and method

technical field

This invention relates generally to evaporation and concentration drying apparatus and methods, and in particular to an improvement in such apparatus and methods for recovering and reusing the heat of vaporization by liquefaction at an elevated temperature, i.e. Latent heat in the decompression evaporation process, so as to save heating energy, and is used to oxidize or carbonize various impurities evaporated at a certain high temperature, such as odors, B.O.D. and C.O.D. filled in evaporation, so as to remove various impurities evaporated And provide good quality condensate.

Background technique

In traditional evaporation equipment, the cooling water used for condensing steam must be added to the equipment together with the heat required for evaporation, that is, the heat of boiling (100Kcal) and the heat of vaporization (latent heat of evaporation, 539Kcal/1). In the case of producing distilled water by evaporating and concentrating wet materials such as wet mud or waste water using the above-mentioned evaporation equipment, a part of environmental pollution impurities such as odors, B.O.D. middle. Various impurities in the steam are liquefied together with the steam when the steam is condensed. The distilled water thus does not meet the permissible standard water quality, so that the distilled water needs to be reprocessed in order to achieve the permissible standard quality.

General evaporation equipment and general evaporation methods cannot recover and reuse the latent heat of evaporation (539Kcal/l) of steam, but waste the latent heat through a condensation system for cooling and condensing steam full of various impurities. Secondly, this waste of latent heat is necessarily accompanied by substantial costs.

In addition, general evaporation equipment or general evaporation methods cannot remove various impurities such as odor, B.O.D. and C.O.D., which are evaporated and liquefied together with steam to reduce the quality of distilled water. As such, distilled water must be treated through an additional water purification process in order to improve the quality of the distilled water. Additional water purification processes to improve distilled water quality are complex and increase the cost of producing distilled water.

When using a reduced-pressure evaporation method to evaporate water into steam, the heat of vaporization can be saved by reducing the pressure corresponding to a certain degree of vacuum. However, this reduced pressure evaporation method still has a problem that the condensed water is full of odor, B.O.D. and C.O.D., so that the condensed water needs to be treated through additional deodorization and water purification processes.

In general heating evaporation equipment, the total heat required to evaporate one liter of zero-degree (0°C) water at atmospheric pressure is 639Kcal. That is, the boiling heat for boiling water at 100°C is 100Kcal, and the vaporization heat for evaporating boiling water is 539Kcal, so the total heat for evaporating one liter of water is 639Kcal, that is, 100Kcal+539Kcal=639Kcal. When using a decompression evaporator to evaporate 1 liter of zero-degree (0°C) water, the water boils at 35°C under a vacuum of about 10 Torr (750mmHg), so that the total heat used to evaporate 1 liter of water is 605Kcal, which is 35Kcal +570Kcal=605Kcal (when the evaporation pressure is 0.1Kg/cm ² .A, the latent heat can be about 570Kcal).

However, general evaporation equipment must use a condenser to condense and liquefy the vapor, so that a large amount of cooling water for condensation must be added to the equipment. Secondly, the latent heat of steam (539Kcal) cannot be recovered and reused, but discarded.

It has been briefly stated that the total heat to be applied to water is 574Kcal or 639Kcal when evaporating one liter of zero degree (0°C) water at atmospheric pressure using either the general reduced pressure evaporation method or the general heating evaporation method. Second, additional energy for supplying cooling water to the condenser must be added to the equipment. In the process of condensing steam, the latent heat of evaporation (539Kcal) cannot be recovered and is discarded. In addition, general evaporation equipment itself cannot remove various environmental pollutants such as odor, B.O.D., and C.O.D. from condensed water, so that condensed water needs to be treated through additional deodorization and water purification processes.

Contents of the invention

Therefore, the object of the present invention is to provide a kind of evaporation and concentration drying equipment and method, wherein, the above various problems are overcome and can provide high-quality condensed water and save vaporization energy, so that by reusing The emerging potential saves heating energy, and can be widely used to make polluted wastewater into distilled water, purify wastewater, and concentrate and dry various environmental pollution muds.

The apparatus and method of the present invention can recover and reuse heating energy, which is applied to the steam so as to heat the steam to a certain high temperature for oxidation or carbonization, and remove various environmental pollutants filled in the steam, such as odor , B.O.D. and C.O.D., etc., so that the device and method can significantly save the cost of heating energy.

Compared with the traditional equipment, the invention can reduce the production cost of the evaporation equipment and the operation cost of the equipment, thereby providing economic benefits for users. Compared with traditional equipment, the equipment of the present invention can also save energy by 2 to 10 times. In the equipment of the present invention, the odor and various impurities in the steam can be oxidized and carbonized and completely removed from the steam when the steam is heated to a high temperature, so that the equipment can provide high-quality distilled water without using another water purification device.

Description of drawings

The above and other objects, features and other advantages of the present invention will be more clearly understood through the following detailed descriptions made in conjunction with the accompanying drawings, wherein

Fig. 1 is a partial sectional view of evaporation and concentration drying equipment of a preferred embodiment of the present invention;

Fig. 2 is the perspective view of a heat recovery device of Fig. 1 equipment, shows the internal structure of this device;

Fig. 3 is a partial cut-away front view of the heat recovery device in Fig. 2, showing the heat exchange state between the counter-current high-temperature steam and the forward-flow low-temperature steam in this device:

Figure 4 is a partial perspective view of the stirring blades and plate steam chambers installed in an evaporator of the apparatus of Figure 1; and

Fig. 5 is a partially enlarged view showing each plate-type steam chamber in Fig. 4 .

Detailed ways

Referring to Fig. 1, wherein shows the structure of the evaporation and concentration drying equipment of a preferred embodiment of the present invention with partial sectional view. In this figure, reference numeral 1 denotes a container for holding wet material to be treated by evaporation. The container 1 equipped with a coil R in it is provided at its top with a first inlet 15a for filling with wet material to be treated, such as water or wet slurry. The outer shell of the vessel 1 is a double structural wall for the recovery of waste heat from the condensed water to be circulated in the vessel 1 . The container 1 is connected to an evaporator 10 for evaporating and concentrating the dried wet material, which is an agitation type evaporator and holds therein a wet material such as waste water or wet mud. The evaporator 10 is provided at its top with a second inlet 15b for selectively filling the wet material to be evaporated. The bottom of the evaporator 10 is circular and has a groove 11 at the bottom of the side wall of the circular bottom. A screw 11s for discharging the slurry to the outside of the evaporator 10 is placed in the groove 11 . In order to stir the wet material in the evaporator 10, a plurality of plate-type semicircular steam chambers 13 are arranged vertically in the evaporator 10, so that the chambers 13 are arranged in the horizontal direction and spaced equidistantly from each other. As shown in Figures 4 and 5. A number of stirring blades 12 are provided between the chambers 13 . Each blade 12 is rotatable in two opposite directions in the space delimited by each chamber 13, thereby agitating the wet material to be evaporated. As shown in FIG. 5, the inner end portions of the opposite side walls of the plate steam chambers 13 are smoothly tapered to a single ridge, so that the stirring blades 12 located between the plate steam chambers 13 are smoothly rotated. Each stirring blade 12 is sleeved on a blade shaft S, and the shaft S extends along the center of the evaporator 10 in the length direction. Each plate-type steam chamber 13 communicates with a steam chamber 14 formed in the double-structured wall panels of the evaporator 10 . The top of the evaporator 10 is connected via a connecting pipe 16 to an overflow prevention chamber 17 which itself is connected to the interior of the evaporator 10 via a U-shaped bend 18 . An elbow 18 extends from the bottom of the chamber 17 to the interior of the evaporator 10 .

A first conduit _R1 extends from the top of the flood prevention chamber 17 to a vapor compressing turbine 20 . The conduit _R1 is provided with a control valve 21 for supplying preheated air to the steam flowing in the conduit _R1 . The rear end of the vapor compression turbine 20 itself is connected to a vapor compression pump 30 via a second conduit _R2 . A third conduit _R3 extends from the vapor compression pump 30 to a heat recovery device 60 . As shown in Figures 1 to 3, the _heat recovery unit 60 adapted to recover heat from high-temperature steam and reuse the recovered heat for preheating low-temperature steam is equipped with a bundle of ninth or steam conduits _R9 , which are located at The devices 60 extend horizontally and are equally spaced apart. The opposite ends of the heat recovery device 60 are themselves connected via fourth and sixth conduits _R4 and _R6 , respectively, to an auxiliary boiler 40 and evaporator 10 with their own heating means. In the auxiliary boiler 40 , the fourth conduit R ₄ is connected to a steam heating coil 42 in front of the nozzle of a burner 41 . The burner 41 is mounted on the front wall of the boiler 40 and generates a flame to be guided to the inside of the boiler 40 . The coil 42 surrounding a steam heating chamber 43 in the boiler 40 is itself connected to the heat recovery unit 60 via a fifth conduit _R5 . In this way, the latent heat of the steam can be recovered by the device 60 and reused for preheating the low temperature steam flowing in the steam conduit _R9 .

A seventh conduit R ₇ with a pressure regulator 51 and a relief valve 52 extends from the vapor chamber 14 of the evaporator 10 at the circular bottom of the evaporator 10 and is connected to the vessel 1 . In vessel 1, the condensate loses heat as it passes through coil R. Thereafter, the condensed water is sent to a condensed water tank 50 to be collected in the tank 50 .

In the operation of the above-mentioned plant, wet material to be evaporated, such as waste water, is introduced into the container 1 through the first inlet 15a of the container 1, which recovers waste heat from the condensed water. The waste water itself is sent to the evaporator 10 via an eighth conduit _R8 , where it is evaporated or concentrated to dryness into vapor. The steam itself flows in turn via the connecting pipe 16 to the flood prevention chamber 17 and is then sent into the turbine 20 via the first conduit R ₁ . The control valve 21 of the first conduit _R1 adds an appropriate amount of preheated air to the steam before it is sent to the turbine 20 . Here, the preheated air added to the steam according to the characteristics of various evaporated impurities filled in the steam is to promote the oxidation of these impurities. However, it should be understood that the steam full of various impurities may be carbonized at high temperature without adding preheated air according to the characteristics of the evaporation body. At this time, the evaporation chamber 10 is evacuated due to the action of the vapor compression turbine 20 and the vapor compression pump 30, so that the evaporator 10 has an internal temperature of about 60° C. and a vacuum ranging from about 300 mmHg to about 400 mmHg Spend. The vapor is thereafter recompressed by the vapor compression pump 30 so that the vapor pressure increases.

The high-pressure steam is itself sent via the third conduit _R3 to the steam conduit _R9 of the heat recovery unit 60 and discharged from the unit 60 to the auxiliary boiler 40 via the fourth conduit _R4 . In the auxiliary boiler 40, the steam is heated by the steam heating means while passing through the steam heating pipe 42 and the steam heating chamber 43, thereby becoming high-temperature steam, and the temperature of the steam ranges from about 600°C to 800°C. As the steam is heated in the boiler 40, various impurities contained in the steam, such as odor, BOD and COD, are removed by oxidation and carbonization. The steam returns to the heat recovery device 60 via the fifth conduit R ₅ after being heated by the boiler 40 . In unit 60, the steam at 600°C to 800°C exchanges heat with live steam which is freshly fed into conduit _R9 of unit 60 and has a low temperature ranging from 60°C to 100°C. In the heat recovery device 60, the steam heated by the steam heating device of the boiler 40 is guided around the steam conduit _R9 by each guide partition of the device 60, and the low-temperature steam passes through the conduit _R9 . That is, the high-temperature steam in the device 60 flows from the rear to the front of the device 60 in a tortuous path and exchanges heat with the low-temperature steam passing through the conduit _R9 from the front to the rear.

As shown in FIG. 2, the guide partitions may be placed vertically in the heat recovery unit 60 so that the partitions are spaced at equal intervals. Each partition will prolong the heat exchange time of the vapor in the device 60 , thereby improving the heat exchange effect of the device 60 . However, in the first stage of plant operation, the water in the boiler 40 is heated by the heating means of the boiler 40 so as to become high-temperature steam. The high-temperature steam from the carbonized or oxidized boiler 40 passes through a tenth conduit R ₁₀ , a third conduit R ₃ with a regulator 41, a heat recovery device 60, a fourth conduit R ₄ , a boiler 40, and a fifth conduit R ₅ , the device 60 and the sixth conduit R ₆ are provided to each plate vapor chamber 13 and vapor chamber 14 of the evaporator 10 . In the evaporator 10, the high-temperature steam supplied from the boiler 40 exchanges heat with the waste water so that the waste water becomes a low-temperature steam of about 60°C to 100°C. The steam of about 60°C to 100°C is sent into the heat recovery device 60 through the above process and absorbs heat of the high temperature steam supplied from the boiler 40 through the fifth conduit _R5 . Due to heat exchange, the temperature of the low-temperature steam increases from 60°C to 100°C to 450°C to 600°C. The preheated steam at 450°C to 600°C is itself discharged from the device 60 to the boiler 40 via the fourth conduit _R4 . Meanwhile, the vapor whose temperature is lowered to 150° C. to 200° C. due to heat exchange in the heat recovery device 60 is discharged to the evaporator 10 through the sixth conduit R ₆ .

The preheated steam at 450°C to 600°C discharged from the device 60 to the boiler 40 via the fourth conduit _R4 is heated in the boiler 40 by the steam heating device of the boiler 40 and sent into the steam heating coil 42 and the steam heating chamber 43, Thereby it is oxidized or carbonized and becomes a high-temperature steam of 600°C to 800°C. The oxidized or carbonized steam of the boiler 40 is sent into the device 60 through the fifth conduit _R5 , and flows from the rear of the device 60 to the front along a tortuous path, and the temperature from 60°C to 100°C is passed through the conduit _R9 from the front to the rear. ℃ low temperature steam exchange heat. Here, heating energy that heats the steam and raises the temperature of the steam to 600° C. to 800° C. by acting on the steam by the steam heating means in the boiler 40 is recovered in the heat recovery means 60 . That is, the heating energy filled in the high-temperature steam of 600°C to 800°C is recovered and reused for preheating the steam flowing through the steam conduit _R9 of the device 60, as shown in FIG. 3 . Due to the preheating, the temperature of the vapor sent from the evaporator 10 increases from 60°C to 80°C to 450°C to 600°C. Since the temperature of the steam to be fed into the boiler 40 is increased from 60°C to 80°C to 450°C to 600°C by heat exchange in the device 60, the heating energy of the heating device of the boiler 40 can be greatly saved.

The vapor discharged from the device 60 through the sixth conduit _R6 and having a temperature of 150° C. to 200° C. and whose various impurities are oxidized or carbonized is supplied to each plate type vapor chamber 13 and vapor chamber 14 of the evaporator 10 . In the evaporator 10, the steam supplied from the device 60 exchanges heat with the waste water, thereby losing its heat of vaporization and being liquefied and becoming relatively high-temperature condensed water, so that the water or wet material of the evaporator 10 is liquefied at a high temperature from The latent heat of 539Kcal (when the evaporation pressure is 1.013Kg/cm ² .A) is recovered in the steam. This condensed water at about 80° C. to 120° C. is itself sent to the coil R of the vessel 1 via a seventh conduit R ₇ having both a pressure regulator 51 and a relief valve 52 . Coil R again recovers waste heat from the condensate. The condensed water is collected in the condensed water tank 50 . When the condensed water is filtered in the tank 50, various impurities that have been oxidized or carbonized are removed from the condensed water, so that the condensed water becomes good distilled water.

In the above examples, waste water was evaporated by the reduced-pressure evaporation method. However, it should be understood that waste water may be evaporated at a certain high pressure not lower than atmospheric pressure. That is, the apparatus of the present invention can evaporate waste water under pressurized conditions.

The operational effects of the present invention will be described below.

The wet material or waste water to be evaporated in container 1 absorbs waste heat from the high temperature condensed water flowing through the coil R. Thereafter, the preheated waste water is naturally introduced into the evaporator 10 through the eighth conduit _R8 due to the depressurizing action of the vapor compression turbine 20 and the depressurizing action of the vapor compression pump 30 . In the evaporator 10, the respective agitating blades 12 agitate the waste water so that the waste water will be evaporated as described below. After mixing the preheated wastewater, the sludge of the wastewater is collected in the groove 11 of the evaporator 10 . The rejects themselves in the groove 11 are discharged to the outside of the evaporator 10 through the reject discharge screw 11s. At the same time, the remaining waste water without slurry absorbs the heat of vaporization from the high-temperature steam of 150° C. to 200° C. flowing in each plate steam chamber 13 and in the steam chamber 14 of the evaporator 10, thereby being evaporated and Become a low-temperature vapor. The waste water itself in the vapor state is sent from the evaporator 10 via the connecting pipe 16 into the overflow prevention chamber 17, which has a U-shaped bend 18 extending from the bottom of the chamber 17 to the inside of the evaporator 10 And adapted to prevent waste water from possibly overflowing the evaporator 10 during evaporation in the evaporator 10 . The vapor of the waste water is thereafter fed into the vapor compression turbine 20 via a first conduit R ₁ extending from the top of the chamber 17 to the vapor compression turbine 20 . Before the steam is fed into the turbine 20, the steam may optionally be added with a predetermined amount of preheated air under the control of a control valve 21, which is placed in front of the steam inlet of the turbine 20.

The vapor from the vapor compression turbine 20 is itself fed to a vapor compression pump 30 where the vapor is compressed to increase its pressure. At this time, the waste water in the evaporator 10 evaporates at a temperature of about 60° C. due to the depressurization condition in the evaporator 10 . In addition, the evaporator 10 achieves a vacuum ranging from about 300 mmHg to about 400 mmHg due to the depressurizing action of the vapor compression turbine 20 and due to the depressurizing action of the vapor compression pump 30 . As indicated by the following basic equation (E-1) for ideal gases, the vapor pressure can be increased by either the turbine 20 or the pump 30 so that the vapor is liquefied at a certain high pressure and a certain high temperature. Of course, the apparatus of the present invention may use a vacuum booster, a vacuum molecular pump or a vapor compression device instead of the vapor compression turbine 20 of the above-mentioned main embodiment.

PV＝n _t RT…………………………………(E-1) where

P - vapor pressure;

V - vapor volume;

T - the absolute temperature of the vapor;

R - gas constant; and

n _t - the total number of moles of each gas contained in the volume V of vapor.

The steam itself passes through the steam conduit R ₉ of the heat recovery unit 60 under the condition that the steam pressure is increased by the turbine 20 and the pump 30 . While passing through vapor conduit R ₉ , the vapor absorbs heat from the high temperature vapor flowing countercurrently around conduit R ₉ in device 60 . The steam full of various impurities is sent to the steam heating chamber 43 of the boiler 40 after being preheated in the conduit _R9 , and is heated to a temperature of 600°C to 800°C by the steam heating device of the boiler 40, thereby being oxidized or carbonized . The oxidized or carbonized high-temperature steam returns to the heat recovery device 60 and flows reversely in the device 60 around the steam conduit _R9 along a tortuous path. At this time, new vapor that is newly fed into the device 60 and has a lower temperature of 60° C. to 100° C. flows in the vapor conduit R ₉ of the device 60 . In the device 60, the steam once heated by the steam heating device of the boiler 40 is guided by the guide partitions placed in the vertical direction of the device 60 and surrounds the steam conduit _R9 , thereby exchanging heat with the new steam, as shown in the figure 2 and 3 are shown.

The steam preheated to a temperature of 450°C to 600°C is sent to the steam heating pipe 42 and the steam heating chamber 43 through the fourth conduit _R4 , thereby becoming oxidized or carbonized high temperature steam of 600°C to 800°C. Simultaneously, the steam which has lost heat energy and whose temperature has been lowered to 150° C. to 200° C. is sent into the respective plate steam chambers 13 and 14 of the evaporator 10 via the conduit R ₆ . While passing through the plate-type steam chambers 13 and 14 of the evaporator 10, steam at 150°C to 200°C exchanges heat with waste water to be liquefied and becomes condensed water at about 80°C to 120°C. This is because, as indicated by Equation E-1 above, since the vapor liquefies at a certain temperature proportional to its vapor pressure, high pressure vapor liquefies at a certain high temperature proportional to its vapor pressure.

The condensed water at about 80° C. to 120° C. is itself fed into the coil R of the vessel 1 via a seventh conduit R ₇ with a pressure regulator 51 and a relief valve 52 . Coil R again recovers waste heat from the condensate and imparts waste heat to the waste water in vessel 1 . The condensed water is collected in the condensed water sump 50 after losing waste heat. On the other hand, steam at a temperature of 60° C. to 100° C. prepared by evaporating waste water using latent heat recovered by the evaporator 10 is sent to the heat recovery unit 60 via the overflow prevention chamber 17 .

Various impurities in the steam, such as odor, B.O.D., and C.O.D., which evaporate together with the steam and fill the steam, are mixed with a predetermined amount of preheated air supplied by the control valve 21, which is installed in the turbine. 20 to the front of the steam inlet. Due to mixing with the preheated air, various impurities of the steam become oxidizable impurities. The oxidizable impurities are sent to the steam heating means of the boiler 40, that is, the steam heating tube 42 and the steam heating chamber 43. Thus, various impurities are oxidized and burned in the boiler 40 in a high-temperature atmosphere of 600°C to 800°C, thereby being removed from the steam. In addition, without adding preheated air according to the characteristics of the steam, the steam full of various impurities can be carbonized in a high-temperature atmosphere of 600°C to 800°C to remove various impurities such as odor, B.O.D., and C.O.D. from the steam . The steam heating energy once applied to the steam by the steam heating means of the boiler 40 to create a high temperature atmosphere is recovered by the means 60 and reused for preheating the low temperature steam in the means 60 . In this regard, the steam heating energy saved by the apparatus of the present invention is equal to the recovered energy used to preheat the steam in the device 60 .

It should be understood that the energy efficiency of the plant of the present invention can be improved by insulating the vessel 1, evaporator 10, auxiliary boiler 40, etc.

In order to measure the effectiveness of the application of the apparatus and method of the present invention, the following example was carried out. That is, excrement as wet material to be evaporated was heated, oxidized and burned at 620°C or heated and carbonized at 620°C. The results are shown in Table (T-1) below. As shown in Table (T-1), the wet material treated by the device of the present invention and the method of the present invention can be most effectively purified.

                                                         

(A) (B)pH 5.8----8.6 9.0 9.8COD 150(mg/l) 6.4(mg/l) 6.6(mg/l)BOD 150(mg/l) 5.6(mg/l) 5.9(mg /l) SS 150 (mg/l) 4.0 (mg/l) 4.5 (mg/l) n-Hexane 30 (mg/l) 0.8 (mg/l) 4.0 (mg/l) TN 60 (mg/l) 16.1 (mg/l) 16.5(mg/l)TP 8(mg/l) 0.033(mg/l) O.034(mg/l)NH ₃ -N - 5.358(mg/l) 4.632(mg/l)

As described above, the present invention can reduce the cost of producing evaporation and concentration drying equipment and the operating cost of the equipment compared with conventional evaporation equipment, thereby providing economic benefits to users. This equipment also maintains its improved performance, so that this equipment can prepare good distilled water at low cost and is widely used for evaporation and concentration drying of toxic waste water and environmental pollution waste water, and for evaporation, concentration and drying of waste mud. Secondly, the heat recovery device of the apparatus of the present invention can recover steam heating energy which was once applied to the steam by the heating device of the boiler in order to heat the steam to a certain high temperature and remove various substances such as odor, B.O.D. and C.O.D. kinds of impurities. The recovered energy is re-used to preheat the steam that is newly fed to the heat recovery unit. In this connection, the amount of heating energy saved by the plant according to the invention is equal to the recovered energy used to preheat the vapor in the heat recovery unit.

Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will understand that various changes, additions and substitutions can be made without departing from the scope and spirit of the present invention. It's all possible.

Claims (3)

1. An evaporation and concentration drying equipment, wherein the improvements include: A container for holding wet material therein, said container has a double-walled structure and is equipped with a coiled pipe therein, and a first inlet is provided at the top thereof for filling wet material into the container, said The coil is connected to a condensate sump: an agitated evaporator for recovering latent heat of vapor and utilizing the recovered latent heat to evaporate wet material, said evaporator being connected to the bottom of said vessel via a conduit for receiving wet material from said vessel, said evaporator comprising: a second inlet at the top of the evaporator; a round bottom; - a groove provided on one side wall near the circular bottom and equipped with a helical groove for discharging the rejects to the outside of the evaporator; A plurality of plate-type semicircular steam chambers communicated with each other, each of the plate-type steam chambers is vertically installed inside the evaporator, so that each plate-type chamber is arranged in the horizontal direction and spaced at equal intervals, and each of the plate-type steam chambers The chamber is connected to said coil of the vessel via a conduit equipped with a pressure regulator and a relief valve: A plurality of agitating blades for agitating the wet material in the evaporator, each blade is located between the plate chambers, and each blade rotates bidirectionally so as to evenly agitate the wet material; a blade shaft extending lengthwise along the center of the evaporator and supporting the stirring blades; and an overflow prevention chamber for preventing liquid from overflowing said evaporator during evaporation, said overflow prevention chamber being connected to the top of the evaporator via a connecting pipe and via a U-shaped bend protruding from its bottom into the interior of the evaporator The tube is connected to the inside of the evaporator; A heat recovery device for recovering the latent heat of the vapor and for preheating the low-temperature vapor fed into it from the evaporator, said device being connected via respective conduits to said evaporator, the steam surrounding a steam heating chamber of an auxiliary boiler The inlet of the heating coil, the plate steam chambers of the evaporator and the outlet of the steam heating coil, the device comprising: a plurality of horizontally extending steam conduits through which low-temperature steam passes; and a plurality of partitions mounted vertically in the unit and equally spaced; The auxiliary boiler is used to receive preheated steam from the heat recovery device and heat the preheated steam to a certain high temperature to oxidize or carbonize the steam. The auxiliary boiler is connected to the heat recovery device and has a burner, the steam heating plate tube and steam heating chamber; a vapor compression turbine and a vapor compression pump for compressing the vapor supplied from the evaporator to increase the vapor pressure, both the turbine and the pump being provided in a conduit extending from the overflow prevention chamber of the evaporator to the heat recovery unit ;as well as A preheat air supply control valve is provided on the conduit preceding the vapor compression turbine, said valve being adapted to control the supply of preheat air to the vapor flowing from the evaporator via the conduit to the heat recovery unit. 2. Apparatus according to claim 1, wherein the inner end portions of the opposed side walls of the plate vapor chambers of the evaporator merge smoothly into a single ridge so that all the plate vapor chambers disposed between Each agitating blade rotates smoothly. 3. A method of evaporation and concentration drying, comprising the following steps: Heating water in an auxiliary boiler to generate steam, and removing various impurities from the steam by carbonizing or oxidizing steam, supplying steam to a plurality of plate steam chambers of an evaporator to make the steam and the moisture in the evaporator waste heat recovery from the steam by discharging the steam to a wet material container coil after the heat exchange through a conduit equipped with a pressure regulator and a relief valve; The internal pressure of the evaporator is increased or decreased by operating the vapor compression turbine and the vapor compression pump, so that the wet material is sent from the container to the evaporator, and the wet material is evenly stirred by the rotation of the evaporator's multiple agitating blades in the opposite direction, so that The wet material exchanges heat with the carbonized steam of 150°C to 200°C flowing in each plate steam chamber and evaporates the wet material, and the steam generated by the wet material of 60°C to 100°C is discharged from the evaporator through a connecting pipe At the same time, collect the slurry residue of the wet material in a groove of the evaporator so as to discharge the slurry residue to the outside; The overflow liquid contained in the vapor of 60°C to 100°C returns to the evaporator through a U-shaped elbow connecting the overflow prevention chamber and the evaporator, and the preheating air is selectively turned on by operating a preheating air supply control valve. Air is supplied to said 60°C to 100°C vapor, and a plurality of steam conduits for sending the 60°C to 100°C vapor into the heat recovery unit by means of both a vapor compression turbine and a vapor compression pump; Make the steam from 60°C to 100°C in each steam pipe of the heat recovery device exchange heat with the high-temperature steam from 600°C to 800°C, the steam from 600°C to 800°C is supplied from the auxiliary boiler and arranged at equidistant intervals of the device Under the guidance of the separated partitions, it flows in reverse along the tortuous path and around the steam pipes in the device, preheats the steam from 60°C to 100°C to 450°C to 600°C, and changes its temperature from 600°C to 600°C due to heat exchange. The steam from ℃ to 800 ℃ lowered to 150 ℃ to 200 ℃ is discharged from the heat recovery device to each plate steam room of the evaporator, and at the same time, the preheated 450 ℃ to 600 ℃ steam is sent to the steam heating plate of the auxiliary boiler tube and steam heating chamber; Burners are used to heat the preheated steam at 450°C to 600°C flowing in both the steam heating coil and the steam heating chamber of the auxiliary boiler, thereby increasing the temperature of the steam from 450°C to 600°C to 600°C to 800°C and oxidize or carbonize various impurities in the preheated steam to remove odors and various impurities, and return the steam at 600°C to 800°C to the heat recovery device so that the high temperature steam at 600°C to 800°C can be combined with heat Low-temperature steam from 60°C to 100°C flowing in each steam pipe of the recovery unit for heat exchange; and Make the steam at 150°C to 200°C in each plate steam chamber of the evaporator exchange heat with the water and wet material in the evaporator, and recover the latent heat of 539 Kcal from the steam by liquefaction at a certain high temperature, so that the steam becomes about 80°C To 120 ℃ condensed water, by means of the conduit equipped with a pressure regulator and a relief valve, the condensed water of about 80 ℃ to 120 ℃ is sent to the coil of the container, so that the condensed water is reconnected with the container The wet material exchanges heat and recovers waste heat from the condensate, and collects the condensate in a condensate pool.

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