JP2007125457A - Organic waste liquid treatment apparatus and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic waste liquid treatment apparatus and method which enable a continuous extraction of distillate which can be discharged, from organic waste liquid etc. without using chemicals. <P>SOLUTION: The organic waste liquid treatment apparatus 1 comprises a first evaporator 18 which evaporates liquid d to be treated, and condenses and extracts purified water with a low concentration of ammonia and high-concentration ammonia water, a second evaporator 20 which evaporates a residue f having not been evaporated in the first evaporator 18, a first partial condenser 19 which condenses steam e evaporated in the first evaporator 18, in two stages, a high-temperature side condensation part and a low-temperature side condensation part, and a second partial condenser 21 which condenses steam h evaporated in the second evaporator 20, in two stages, a high-temperature side condensation part and a low temperature side condensation part. Distillate b condensed in the high-temperature side condensation part of the first partial condenser 19, and distillate c condensed in the low-temperature side condensation part of the second partial condenser 21 are returned to the first evaporator 18 as a part of the liquid d to be treated. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention reduces the volume of organic waste liquid such as stored manure discharged from barns and so-called digested liquid after anaerobic fermentation of the organic waste liquid to extract biogas, and facilitates handling such as storage and transportation. The present invention relates to a processing apparatus and a processing method for organic waste liquid that produce a simple fertilizer and can be continuously processed.

  For example, in biogas plants, biogas is collected from stored manure by anaerobic fermentation, but a large amount of nitrogen and SS remain in the digestive juice after the treatment. It cannot be discharged directly into the water environment. Therefore, it is desired to use digestive juice effectively as liquid fertilizer. However, since the digestive juice has almost no change in weight or volume from the state before collecting biogas, storage and transportation of a large amount of digestive juice has been a problem. For example, in a barn with 200 cattle, approximately 16 tons of stored manure is discharged per day, but since it is sprayed as fertilizer twice a year in spring and autumn, approximately 3000 tons of digestive juice for half a year An extremely large tank for storing the water is required. In addition, it is sufficient if an environment in which digestive juice can be sprayed around the tank as a liquid fertilizer is required, but when spraying it on distant land, labor and cost of transportation are required. Furthermore, since the digestive juice cannot be used as a liquid fertilizer in a place where the agricultural field is small and cannot be sprayed, wastewater treatment is performed with great effort and cost.

In order to solve such problems, Japanese Patent Application Laid-Open No. 2003-117593 proposes an organic waste liquid treatment apparatus and treatment method. This is a stock solution of organic waste containing ammonia and water, a solution obtained by pre-treating organic waste (partial removal of solids, etc.), and digestion and desorption after organic waste is treated with methane fermentation. Liquid, or liquid from which digestion detachment liquid has been partially removed, and is concentrated by heating and concentrating to separate into concentrated liquid and condensed water, eliminating the need for wastewater treatment equipment and concentrating steps The condensed water obtained in (1) can be discharged by a simple method, and is described as a processing apparatus and a processing method for improving the usability and transportability when the concentrated liquid is effectively used as a liquid fertilizer.

  FIG. 4 is a diagram showing a schematic configuration of the organic waste liquid treatment apparatus described in the publication. This shows a case in which digestive liquid after methane fermentation of organic waste such as livestock manure is processed. The digested liquid in the digested liquid storage tank 100 is guided to the absorption tower 111 in the first evaporator 110 by the pump 101, and is heated by the heat exchangers 102, 103, and 104 during that time. In the digested liquid sprayed on the absorption tower 111, evaporated ammonia is introduced into the heat exchanger 113 of the first evaporator 110 via the pump 112. A digestion liquid from which ammonia has been removed circulates in the heat exchanger 113, and the introduced ammonia is cooled and condensed by exchanging heat with the circulation digestion liquid.

  The condensed ammonia water is cooled by the heat exchanger 104 and separated into concentrated ammonia on the gas side and the remaining liquid by the gas-liquid separator 105. The separated liquid is sprayed on the absorption tower 111, and the concentrated ammonia on the gas side is cooled and condensed by the heat exchanger 102 and stored in the ammonia tank 200. This concentrated ammonia water can be used as a liquid fertilizer. On the other hand, the digested liquid from which ammonia has been removed is extracted by the pump 114 and heated by the heater 115, further heated by the heat exchanger 113 and circulated, and a part of the digested liquid is extracted to the second evaporator 120. be introduced.

  In the second evaporator 120, the digested liquid from which ammonia has been removed is sent out to the pump 121 and heated and circulated in the heater 122 and further in the heat exchanger 123. The digested liquid is heated and concentrated by the heater 122 and the heat exchanger 123, and the evaporated water is taken out from the vapor outlet 124. The extracted steam is introduced into a wet gas cleaning device 126 such as a scrubber through a pump 125, where gas cleaning is performed. The liquid after cleaning from the wet gas cleaning device 126 is mixed with the circulating digestion liquid of the second evaporator 120. The wet gas scrubber 126 is supplied with chemicals for gas scrubbing with sodium hydroxide aqueous solution and nitric acid aqueous solution from chemical tanks 130 and 140, respectively.

The steam cleaned by the wet gas cleaning device 126 is cooled and condensed by exchanging heat with the circulating digested liquid in the heat exchanger 123 described above, and taken out as condensed water (distilled water). The condensed water is cooled by the heat exchanger 103 via the condensed water receiving tank 127 and the pump 128 and stored in the condensed water (distilled water) storage tank 300. Condensed water can be discharged into ordinary rivers as it is or after simple treatment. On the other hand, the digested liquid heated and concentrated by the heater 122 and the heat exchanger 123 is extracted from the second evaporator 120 and stored in the concentrated liquid storage tank 400. This concentrated digestive juice can be used as a liquid fertilizer, and its utilization and transportability are enhanced by concentration.
Japanese Unexamined Patent Publication No. 2003-117593 (page 4-5, FIG. 1)

In such a conventional organic waste liquid processing apparatus and processing method, in order to obtain purified water that satisfies the drainage standard, chemicals for gas cleaning such as aqueous sodium hydroxide solution and aqueous acid solution are supplied from the chemical tanks 130 and 140 to the wet gas cleaning device 126. Therefore, the cost for processing the digestive juice increases, and it takes time to supply chemicals.
In addition, in the conventional organic waste liquid treatment apparatus and treatment method, when using a liquid obtained by pre-treating organic waste (partial removal of solids etc.), for example, it is considered to use concentrated sulfuric acid, If concentrated sulfuric acid is used, the concentrated solution becomes acidic and must be neutralized. Therefore, the safety and cost of using chemicals are increased, which is not preferable.

  Therefore, in order to solve such problems, the present invention has an object to provide an organic waste liquid treatment apparatus and treatment method for continuously taking out a distillate that can be discharged from an organic waste liquid without using chemicals. To do.

  The organic waste liquid treatment apparatus according to the present invention condenses evaporated vapor for a treatment liquid containing ammonia, an ammonium salt, and moisture, such as an organic waste liquid and digestive liquid obtained by subjecting the organic waste liquid to a certain treatment. In this way, the purified water having a low ammonia concentration and the high concentration ammonia water are separated and taken out, and a first evaporator that evaporates the treatment liquid and a residue that has not evaporated in the first evaporator are removed. A second evaporator that evaporates, a first partial condenser that condenses the vapor evaporated in the first evaporator in two stages of a high-temperature side condensing unit and a low-temperature side condensing unit, and the vapor evaporated in the second evaporator A second partial condenser that condenses the high-temperature-side condenser section and the low-temperature-side condenser section in two stages, and the condensed liquid condensed in the high-temperature-side condenser section of the first partial condenser, The distilled liquid condensed in the low temperature side condensing part of the vessel is a part of the treatment liquid. Characterized in that it is obtained by so as to reflux to said first evaporator.

Further, in the organic waste liquid processing apparatus according to the present invention, the first evaporator and the second evaporator evaporate in the second evaporator rather than the evaporation amount of the processing liquid evaporated in the first evaporator. It is preferable that the evaporation amount of the treatment liquid is set to be large.
In the organic waste liquid treatment apparatus according to the present invention, a tank for storing ammonia obtained in the low temperature side condenser is connected to the first partial condenser, and a high temperature side condenser is connected to the second partial condenser. It is preferable that a tank for storing the distillate obtained in the above as purified water is connected, and a tank for storing a residue that has not evaporated is connected to the second partial condenser.

  The organic waste liquid treatment apparatus according to the present invention is a concentrator in which each of the first evaporator and the first partial condenser and the second evaporator and the second partial condenser are integrally configured. An evaporator to which the treatment liquid is supplied, a plurality of heat transfer tubes provided inside the evaporator and through which steam passes, a steam tube for sending the steam generated in the evaporator to the heat transfer tube, and an evaporator And a compressor provided in a steam pipe that feeds into the heat transfer pipe as superheated steam adiabatically compressed, and the superheated steam sent to the heat transfer pipe through the steam pipe is supplied into the evaporator When the treatment liquid touches the heat transfer tube and evaporates, latent heat is taken away and condenses, and the portion of the treatment liquid that touches the heat transfer tube at a high temperature and takes out the condensed distilled liquid is Condensate is used as the condensing part, and the condensed liquid is obtained by touching the heat transfer tube while the temperature of the processing liquid is low. Ri is preferably a portion is obtained by said low-temperature side condenser section issuing.

Further, in the organic waste liquid treatment apparatus according to the present invention, the high temperature side condensing unit and the low temperature side condensing unit are configured by a block in which a plurality of the heat transfer tubes are divided in the vertical direction, and the high temperature side condensing unit However, it is constituted by a lower block into which steam pressurized by the compressor is sent, and the low temperature side condensing part is on the secondary side of the high temperature side condensing part, and the treatment liquid sprayed from above is It is preferable that the upper block is touched first.
In the organic waste liquid treatment apparatus according to the present invention, it is preferable that the concentrator depressurizes the inside of the evaporator to a predetermined pressure by a vacuum pump connected to the evaporator.

On the other hand, the method for treating an organic waste liquid according to the present invention is a method for treating an organic waste liquid or a treatment liquid containing ammonia, ammonium salt and moisture, such as a digested liquid obtained by subjecting the organic waste liquid to a certain treatment. The purified water having a low ammonia concentration and the high-concentration ammonia water are condensed and extracted, and are not evaporated in the first evaporation step for evaporating the treatment liquid and the first evaporation step. A second evaporation step for evaporating the residue, a first condensation step for condensing the vapor evaporated in the first evaporation step in two stages of high temperature side condensation and low temperature side condensation, and the vapor evaporated in the second evaporation step at a high temperature. A second condensing solution that condenses in two stages, a side condensing step and a low temperature condensing step, condensing on the high temperature side by the first condensing step, and a distillate condensed on the low temperature side by the second condensing step And the above Characterized in that as part of the management solution was to be returned to the first evaporation step.
In the organic waste liquid treatment method according to the present invention, the first evaporation step and the second evaporation step evaporate in the second evaporation step rather than the evaporation amount of the treatment solution evaporated in the first evaporation step. It is preferable that the evaporation amount of the treatment liquid is large.

  Therefore, in the organic waste liquid processing apparatus and processing method according to the present invention, the processing liquid is evaporated in two stages of the first evaporator and the second evaporator, and the vapor generated in each is condensed on the high temperature side and the low temperature side. In this way, the water is condensed so that a solution other than the distilled liquid taken out as ammonia water or effluent water is returned to the first evaporator as a reflux liquid. This makes it possible to obtain high-concentration ammonia water in the continuous treatment without using chemicals, and it is possible to efficiently extract a large amount of discharged water from the treatment liquid to be supplied.

  Further, according to the present invention, using a concentrator integrated with an evaporator and a partial condenser, steam pressurized by adiabatic compression of the compression / condenser is fed into the heat transfer tube and sprayed onto the heat transfer tube. When the treatment liquid touches, new steam is generated, while the superheated steam in the heat transfer tube is deprived of latent heat and condenses, so it is installed outside the system that always heats the heat transfer tube to evaporate the treatment liquid. It is possible to reduce the burden on the heating device and the cooling device outside the system that condenses the superheated steam.

Next, an embodiment of an organic waste liquid treatment apparatus and treatment method according to the present invention will be described below with reference to the drawings. In the biogas plant, as described above, biogas such as CH ₄ , CO ₂ , H ₂ S, and H ₂ is collected from the stored manure discharged from the barn, and the organic waste liquid treatment apparatus of this embodiment uses the biogas. The digested liquid obtained from the gas plant is applied to a solid-liquid separator and separated into a solid and a filtrate. The solid content obtained here can be used as fermented compost as it is because the organic matter is mineralized by methane bacteria in the biogas plant. In the present embodiment, the volume of the digested filtrate from which the solid content has been removed (hereinafter, the filtrate thus obtained is referred to as “stock solution”) can be reduced, and a large amount can be discharged into a general river. It is what I did.

FIG. 1 is a diagram conceptually showing an embodiment of an organic waste liquid treatment apparatus. First, the structure of the organic waste liquid treatment apparatus 1 will be described.
The organic waste liquid treatment apparatus 1 has a digestive liquid tank 11 for temporarily storing digestive liquid sent from a biogas plant, to which a metering pump 12 for sending a predetermined amount of digestive liquid to the secondary side is connected. Has been. A solid-liquid separator 13 is connected via the metering pump 12. For example, a filter press, a screw press, or a centrifugal separator is used as the solid-liquid separator 13.

  The solid-liquid separator 13 is connected to a compost tank 14 for storing the solid content separated and discharged from the digested liquid, and further preheats the stock solution from which the solid content has been removed from the digested liquid. A heating container 15 is connected. Sending the stock solution from which the solid content has been removed using the solid-liquid separator 13 is because, for example, in the digestive liquid from the biogas plant that handles stored manure, impurities such as waste remain without being fermented. This is so as not to adversely affect the evaporator or the like connected to the secondary side.

  The organic waste liquid treatment apparatus 1 of the present embodiment is configured to separate the stock solution into purified water and ammonia water by continuous treatment, and there is a supply pump 16 on the secondary side of the heating container 15 and constant per unit time. An amount of stock solution is sent continuously. A mixing tank 17 is connected to the supply pump 16, and a first evaporator 18 is connected to the end of the mixing tank 17. The first evaporator 18 is connected to a first partial condenser 19 to which the vapor of the raw liquid evaporated there is sent, and a second evaporator 20 to which the raw liquid remaining without being evaporated by the first evaporator 18 is sent. Yes. The second evaporator 20 is connected to a second partial condenser 21 into which the vapor evaporated there is sent, and a tank 23 into which the stock solution remaining without being evaporated in the second evaporator 20 is sent.

  The first divider 19 and the second divider 21 condense the vapor generated in the first evaporator 18 and the second evaporator 20 separately at two stages of temperature, so-called partial condensation. is there. Since the ammonia contained in the stock solution has a lower boiling point than water and the evaporated and vaporized ammonia is less likely to condense than water, the first and second dividers 19 and 21 have a low ammonia concentration. Thus, a high temperature side condensing part that condenses the high boiling point in the high temperature zone and a low temperature side condensing part that condenses the low boiling point in the low temperature zone so as to increase the ammonia concentration are provided.

  For the evaporators 18 and 20 and the condensers 19 and 21, for example, the following configurations are used. The first evaporator 18 and the second evaporator 20 are provided with heat transfer tubes in the evaporator, and the heat transfer tubes are generated by a boiler so that the undiluted liquid sprayed and touches the heat transfer tubes to evaporate. It is comprised so that steam may be sent. The first and second dividers 19 and 21 connected to the first and second evaporators 18 and 20, respectively, have cooling towers installed as cooling sources for the high-temperature side condenser and the low-temperature side condenser. A flow path is formed so that the cold water generated there circulates both. In that case, it is comprised so that a temperature difference may arise between a high temperature side condensation part and a low temperature side condensation part by adjusting the flow volume of cold water.

  In the first divider 19, a high-temperature side condensing part from which a distillate having a low ammonia concentration is taken out is connected to the mixing tank 17, and a low-temperature side condensing part from which a distillate having a high ammonia concentration is taken out is connected to the tank 22. ing. On the other hand, in the second evaporator 20, a high temperature side condensing part for taking out a distillate having a low ammonia concentration is connected to the tank 24, and a low temperature side condensing part for taking out a distillate having a high ammonia concentration is connected to the mixing tank 17. That is, in the organic waste liquid treatment apparatus 1 of this embodiment, two sets of evaporators and partial condensers are used to perform evaporation and condensation to continuously extract ammonia water and purified water from the stock solution. In this case, the reflux structure is such that the distillate having a low ammonia concentration taken out from the partial condenser is returned to the evaporator again.

  By the way, since the stock solution obtained from the biogas plant contains a large amount of phosphorus, potassium, ammonia nitrogen, etc. in addition to water, the finally obtained distillate is defined as a drainage standard that can be discharged. It is necessary not to exceed the total nitrogen content of 120 mg / L. In this regard, the conventional organic waste liquid treatment apparatus has been purified using chemicals. In this embodiment, the stock solution is evaporated and condensed in two stages, ie, the first evaporator 18 and the first partial condenser 19, the second evaporator 20 and the second partial condenser 21, and further the partial ammonia is condensed. A distillate (purified water) having an ammonia content equal to or less than a reference value is efficiently taken out by refluxing a low-concentration distillate and adding it to the stock solution to cause evaporation and condensation again. In addition, the liquid mixture of the undiluted | stock solution sent out from the mixing tank 17 and the refluxed distillate is called "processing liquid" below.

  That is, in the first evaporator 18, ammonia having a low boiling point evaporates before water, so that the treatment liquid (residue) that has not evaporated is supplied to the second evaporator 20 in a state where the ammonia concentration is low, and again there. Purified water that can be discharged is taken out by evaporating and contracting with the second partial condenser. And the low ammonia concentration distillate fractionated by the first and second fractionators 19 and 21 exceeds the drainage standard and cannot be included in the effluent water. If it becomes the ammonia water which becomes, it will become inefficient thing with which the ratio taken out from the supplied stock solution as discharge water fell. Therefore, in the present embodiment, purified water that can be discharged at a high rate is taken out by refluxing and reprocessing the distillate having a reduced ammonia concentration and reprocessing.

  In such a configuration, the conditions for the reflux amount are set so that the total evaporation amount in the first and second evaporators 18 and 20 is reduced and the separation of water and ammonia is improved. Here, with respect to the first stage evaporation performed in the first evaporator 18, the evaporation amount is suppressed to be small, and the first regenerator 19 for condensing the vapor takes a large amount of reflux to be recirculated. On the other hand, with respect to the second stage evaporation performed in the second evaporator 20, the evaporation amount is increased, and the recirculation amount to be refluxed is reduced as much as possible in the second partial condenser 21 that condenses the vapor. This is because a large amount of purified water that can be discharged from the stock solution can be taken out and ammonia water can be reduced. Specifically, the following flow rate ratio is taken as an example.

FIG. 2 is a block diagram showing the distillation section after the mixing tank 17 that constitutes the organic waste liquid treatment apparatus 1, and particularly shows numerical values of the flow rate ratio and the ammonia concentration in the fluid in each treatment step. .
First, during the steady operation in which the operation of the organic waste liquid treatment apparatus 1 is continuously performed, the feed pump 16 supplies the raw material a having a flow rate (100) from the heating container 15 to the mixing tank 17, and the first partial condenser. A distillate (reflux) b having a flow rate (20) is returned from 19, and a distillate (reflux) c having a flow rate (10) is returned from the second condenser 21. The processing liquid d is set to flow out.

  Accordingly, the flow rate (130) of the processing liquid d supplied to the first evaporator 18 is set to a flow rate (30) with a small amount of evaporation in the first stage, and the recirculation amount to be refluxed from the first divider 19 is reduced. Therefore, (20) of the evaporation amount (30) is sent to the mixing tank 17 and refluxed to the first evaporator 18. On the other hand, the flow rate (100) of the processing liquid (residue) f that has not evaporated in the first evaporator 18 is supplied to the second evaporator 20. In the second evaporator 20 in the second stage, the amount of evaporation is increased to (80), and the amount of reflux returning from the second divider 21 to the first evaporator 18 is set to (10).

Next, an embodiment of the organic waste liquid treatment method will be described according to the flow of treatment performed by the operation of the organic waste liquid treatment apparatus 1 shown in FIG.
The digested liquid sent from the biogas plant is temporarily stored in the digested liquid tank 11, and a predetermined amount of digested liquid is sent to the solid-liquid separator 13 by the metering pump 12. In the solid-liquid separator 13, the stock solution from which the solid content has been removed by centrifugation is sent to the heating container 15, and the solid content such as sawdust is placed in the compost tank 14. The solid content thus sent to the compost tank 14 is used as fermented compost containing inorganic nitrogen, phosphorus, and potash. In the heating container 15, the stock solution is heated by a heater while being stirred and preheated. Then, a constant amount of the stock solution is supplied to the mixing tank 17 per unit time by the supply pump 16.

  Here, the flow rate of the stock solution a supplied from the supply pump 16 per unit time will be described as (100). Since the flow rate and ammonia concentration in each step are shown in FIG. 2, the following will be described with reference to FIG. The stock solution a at the flow rate (100) has an ammonia concentration of 1200 mg / kg. At the time of steady operation, the reflux liquid b at the flow rate (20) at the ammonia concentration of 445 mg / kg is returned from the first divider 19, and the flow rate (10) at the ammonia concentration of 1805 mg / kg from the second divider 21. The reflux liquid c is returned.

  From the mixing tank 17, the treatment liquid d having a flow rate (130) with the ammonia concentration lowered to 1130 mg / kg is fed into the first evaporator 18. The first evaporator 18 is set so as to reduce the amount of evaporation in the first stage. As described above, the flow rate (30) of the flow rate (130) evaporates, and the vapor e is sent to the first partial condenser 19. Will be sent. On the other hand, the flow rate (100) of the flow rate (130) is sent to the second evaporator 20 side as the residue f in order to increase the evaporation amount in two stages. At this time, since the boiling point of ammonia is low, a lot of ammonia is evaporated and contained in the vapor e, and the ammonia concentration of the vapor e shows a high value of 4198 mg / kg, and conversely, the residue f is 210 mg / kg. Ammonia concentration decreases.

  In the first partial condenser 19, when high-concentration ammonia e is first sent to the high-temperature side condensing part, the distillate in which water having a high boiling point is first condensed is returned to the mixing tank 17 as the reflux liquid b. . And the vapor | steam which passed the high temperature side condensation part is sent to a low temperature side condensation part, and is condensed, The distillate becomes ammonia water g and is stored in the tank 22. FIG. In the first divider 19, since the reflux amount is set so as to increase, the supplied steam e is condensed as much as possible to the reflux liquid b in the high-temperature side condensing part of the flow rate (30). Then, ammonia water g having a flow rate (10) is condensed in the low temperature side condensing part. At this time, the ammonia concentration of the reflux liquid b is as low as 445 mg / kg as described above, and conversely, the ammonia water g is as high as 11700 mg / kg.

  The low ammonia concentration residue f sent from the first evaporator 18 to the second evaporator 20 further evaporates here, and the vapor h is taken out and sent to the second partial condenser 21 and does not evaporate. The residue i is stored in the tank 23. Also at this time, since the boiling point of ammonia is low, much ammonia is evaporated and contained in the vapor h. Therefore, the ammonia concentration of the steam h was 259 mg / kg, and conversely, the residue i had a low ammonia concentration of 13 mg / kg.

  On the other hand, when the steam h supplied to the second partial condenser 21 is first sent to the high-temperature side condensing part, the water having a high boiling point is first condensed, and the distillate having an ammonia concentration of 40 mg / kg is the drainage standard. Is stored in the tank 24 as purified water (discharged water) j. And the vapor | steam which passed the high temperature side condensation part is sent to a low temperature side condensation part, is condensed, a distillate is obtained, and this distillate is returned to the mixing tank 17 as the recirculation | reflux liquid c. In the second partial condenser 21, the flow rate (70) is condensed from the supplied flow rate (80) of steam h into the discharged water j as much as possible in the high-temperature side condensing part, and the remaining flow rate (10) is condensed in the low-temperature side condensing part. Thus, the reflux liquid c is obtained.

Therefore, in the present embodiment, the stock solution a delivered from the supply pump 16 is continuously processed, and the flow rate (70) of the stock solution a of the flow rate (100) supplied per unit time is discharged to the tank 24 as discharged water. The flow rate (10) is collected as ammonia water, and the flow rate (20) is taken out as a residue i to the tank 23.
At this time, the vaporization is performed in two stages of the first evaporator 18 and the second evaporator 20, and the steam generated in each is condensed to condense on the high temperature side and the low temperature side, and the tank is obtained as ammonia water g or effluent water j. Distilled liquids other than those taken out at 22 and 24 are returned to the first evaporator 18 as reflux liquids b and c. As a result, high-concentration ammonia water g can be obtained in the continuous treatment, and 70% of the supplied stock solution can be efficiently taken out as discharge water j.

  By the way, in the said embodiment, the 1st evaporator 18 and the 1st divider 19 and the 2nd evaporator 20 and the 2nd divider 21 were mentioned as an example, and what was each comprised separately was demonstrated. However, these may be integrally configured. For example, FIG. 3 shows a concentrator in which an evaporator and a partial condenser are integrally configured. FIG. 3 is a diagram conceptually showing the structure of the concentrator.

In the concentrator 30, the treatment liquid is sprayed into the evaporator 31, and the falling treatment liquid is heated by the plurality of heat transfer tubes 32. The generated steam is configured to be sent. That is, a steam pipe 33 is connected to the evaporator 31, and a compressor 34 for adiabatically compressing the generated steam is provided there.
Therefore, in the concentrator 30, the steam pressurized by the adiabatic compression of the compressor 34 is sent to the heat transfer tube 32, and the treated liquid sprayed on the heat transfer tube 32 is touched to generate new steam. On the other hand, the superheated steam in the heat transfer tube 32 is configured to be deprived of latent heat and condensed.

  Further, the concentrator 30 is configured to evacuate the inside so as to lower the boiling point. That is, a vacuum pump 35 is connected to the concentrator 30, the inside is maintained at a pressure of 25 kPa abs., And the evaporation and condensation of the treatment liquid is performed at around 65 ° C., which is the boiling point of water at the same pressure. Yes. In the concentrator 30, heat transfer tubes 32 are installed in units of several hundreds, and three blocks divided into a predetermined number in the vertical direction are formed. And the steam pipe 33 is connected so that the superheated steam pressurized through the compressor 34 may be sent into the lowest block. As described above, the heat transfer tube 32 condenses the steam and is also configured as a partial condenser.

  Specifically, the lower part and the middle part of the heat transfer tube 32 divided into three blocks are configured as the high temperature side condensing unit 36, and the upper part of the heat transfer tube 32 is configured as the low temperature side condensing unit 37. In other words, the steam in the heat transfer tube 32 is deprived of latent heat and condensed by the processing liquid sprayed in the evaporator 31, but the high boiling content is mainly condensed because the temperature of the processing liquid rises from the middle stage to the lower stage. In the upper stage, the low-boiling component is mainly condensed because the processing liquid having a lower temperature first touches the heat transfer tube 32. The condensing units 36 and 37 are provided with auxiliary tanks 38 and 39 for storing the distillate condensed in each step.

Therefore, if the first evaporator 18 and the first partial condenser 19, and the second evaporator 20 and the second partial condenser 21 of the embodiment are replaced with the concentrator 30, the organic material described in the embodiment is used. The effluent treatment is performed as follows.
First, in the concentrator 30 replaced with the first evaporator 18 and the first partial condenser 19, the evaporator 31 is processed from the input line 41 to the mixing tank 17 (refer to FIG. 1 and FIG. 2 as appropriate). Liquid d is supplied. The processing liquid d sent to the concentrator 30 is sprayed on the heat transfer tube 32 in the evaporator 31 and partially touches the surface to evaporate. At that time, the treatment liquid d falls while touching the heat transfer tubes 32 arranged in the vertical direction, and the residue that has not evaporated becomes the residue f.

  Since the inside of the concentrator 30 is evacuated, the treatment liquid d evaporates even at a low temperature. Then, the vapor evaporated by touching the heat transfer tube 32 is adiabatically compressed by the compressor 34 in the middle of the steam tube 33, and is sent to the heat transfer tube 32 in a pressurized state. At the start of operation, superheated steam is temporarily sent from outside the system to the heat transfer tube 32, thereby causing evaporation of the processing liquid that has touched the heated heat transfer tube 32. Accordingly, the superheated steam in the heat transfer tube 32 is condensed by depriving of latent heat when the treatment liquid sprayed in the evaporator 31 touches the heat transfer tube 32.

  At that time, in the high temperature side condensing section 36, the temperature of the treatment liquid that touches the middle and lower heat transfer tubes 32 is increased, so that the superheated steam is condensed at a temperature slightly lower than the boiling point, and the distillate in the auxiliary tank 38. enter. Then, the superheated steam that has not been condensed in the high temperature side condensing unit 36 is sent to the low temperature side condensing unit 37 where it is completely condensed and the distillate is stored in the auxiliary tank 39. Then, in the concentrator 30 constituting the first evaporator 18, the distillate in the auxiliary tank 38 is sent out by a predetermined amount as the reflux liquid b and returned again to the concentrator 30 constituting the first partial condenser 19. . On the other hand, the distillate stored in the auxiliary tank 39 is sent to the tank 22 as ammonia water g.

  On the other hand, the residue f that has not evaporated in the evaporator 31 is supplied to the concentrator 30 that constitutes the second evaporator 20, and is similarly sprayed onto the heat transfer tube 32 in the evaporator 31 to partially evaporate. Those that have not evaporated take residue i, which is taken out to tank 23 Further, the inside of the concentrator 30 is also evacuated, and the residue f evaporates at a low temperature, and the vapor evaporated by touching the heat transfer tube 32 is subjected to adiabatic compression by the compressor 34 in the middle of the steam tube 33. It is fed into the heat transfer tube 32 in a pressurized state. Then, at the start of operation, superheated steam is temporarily sent from outside the system to the heat transfer tube 32, thereby causing evaporation of the processing liquid that has touched the heated heat transfer tube 32.

  The superheated steam in the heat transfer tube 32 is condensed by depriving latent heat when the processing liquid sprayed in the evaporator 31 touches the heat transfer tube 32, but is heated at a temperature slightly lower than the boiling point in the high temperature side condensing unit 36. The steam is condensed and the distillate enters the auxiliary tank 38, and the distillate condensed in the low temperature side condensing unit 37 enters the auxiliary tank 39 and is stored. In the concentrator 30 constituting the second evaporator 20, the distillate in the auxiliary tank 38 is taken out into the tank 24 as effluent water j, and the distillate stored in the auxiliary tank 39 is a predetermined amount as the reflux liquid c. It is sent out and returned to the concentrator 30 constituting the first divider 19 again.

  Therefore, according to the organic waste liquid treatment apparatus using such a concentrator 30, high-concentration ammonia water g can be obtained even in the continuous treatment as in the above embodiment, and 70% of the supplied stock solution is discharged. It can be taken out efficiently as water j. Then, by using the concentrator 30 to evaporate and condense, a heating device provided outside the system that constantly heats the heat transfer tube 32 in order to evaporate the processing liquid, or conversely, superheated steam is condensed. Similarly, the burden on the cooling device outside the system can be reduced.

As mentioned above, although one Embodiment was described about the processing apparatus and the processing method of the organic waste liquid concerning this invention, this invention is not limited to this, A various change is possible in the range which does not deviate from the meaning.
In the above embodiment, the supply amount of the processing liquid d, the evaporation amount in the first evaporator 18 or the second evaporator 20, or the first divider 19 or the second divider at the flow rate as shown in FIG. Although the ratio of partial reduction in the vessel 21 is set, this is an example, and other flow rates may be set.

It is the figure which showed notionally one Embodiment of the organic waste liquid processing apparatus. It is the block diagram which extracted and showed the distillation part which comprises the organic waste liquid processing apparatus of embodiment, Comprising: The flow rate ratio in each process process and the ammonia concentration in a fluid are shown numerically. It is the figure which showed notionally the structure of the concentrator which comprised the evaporator and the partial condenser integrally. It is the figure which showed schematic structure of the conventional organic waste liquid processing apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Organic waste liquid processing apparatus 11 Digestion liquid tank 12 Metering pump 13 Solid-liquid separator 14 Compost tank 15 Heating container 16 Supply pump 17 Mixing tank 18 1st evaporator 19 1st partial condenser 20 2nd evaporator 21 2nd minute Condenser 22, 22, 23 Tank a Stock solution b, c Reflux solution d Treatment liquid e, h Steam f, i Residual g Ammonia water j Discharged water

Claims (8)

For treatment liquids containing ammonia, ammonium salts, and moisture, such as digestive liquid that has been subjected to a certain treatment on organic waste liquid and its organic waste liquid, purified water with low ammonia concentration and high concentration ammonia water by condensing evaporated vapor In an organic waste liquid treatment device that is separated and removed,
A first evaporator for evaporating the treatment liquid;
A second evaporator for evaporating the residue that has not evaporated in the first evaporator;
A first partial condenser that condenses the vapor evaporated in the first evaporator in two stages, a high temperature side condensing unit and a low temperature side condensing unit;
A second partial condenser that condenses the vapor evaporated in the second evaporator in two stages of a high temperature side condensing part and a low temperature side condensing part,
The distillate condensed in the high temperature side condensing part of the first partial condenser and the distillate condensed in the low temperature side condensing part of the second partial condenser are returned to the first evaporator as a part of the processing liquid. An organic waste liquid treatment apparatus, characterized by being made to cause In the processing apparatus of the organic waste liquid of Claim 1,
The first evaporator and the second evaporator are set so that the evaporation amount of the processing liquid evaporated in the second evaporator is larger than the evaporation amount of the processing liquid evaporated in the first evaporator. An organic waste liquid treatment apparatus characterized by In the processing apparatus of the organic waste liquid of Claim 1 or Claim 2,
A tank for storing ammonia obtained at the low temperature side condenser is connected to the first partial condenser, and a tank for storing the distilled liquid obtained at the high temperature side condenser as purified water is connected to the second partial condenser. The organic waste liquid treatment apparatus is characterized in that a tank for storing a residue that has not evaporated is connected to the second condenser. In the processing apparatus of the organic waste liquid in any one of Claims 1 thru | or 3,
The first evaporator and the first partial condenser, and the second evaporator and the second partial condenser are each a concentrator configured integrally.
An evaporator that is supplied with the treatment liquid, a plurality of heat transfer tubes that are provided inside the evaporator and through which steam passes, a steam tube that sends steam generated in the evaporator to the heat transfer tube, and generated in the evaporator And a compressor provided in the steam pipe for feeding the steam into the heat transfer pipe as superheated steam adiabatically compressed,
When the superheated steam sent to the heat transfer tube via the steam pipe is supplied into the evaporator and the treatment liquid touches the heat transfer pipe and evaporates, the latent heat is taken away and condensed. The portion where the condensed liquid is extracted by touching the heat transfer tube in a state where the temperature is high is referred to as the high-temperature side condensing portion, and the portion where the condensed liquid is extracted by touching the heat transfer tube when the temperature of the treatment liquid is low An organic waste liquid treatment apparatus characterized by being a condensing unit. In the processing apparatus of the organic waste liquid described in Claim 4,
The high temperature side condensing unit and the low temperature side condensing unit are configured by blocks in which a plurality of the heat transfer tubes are divided in the vertical direction, and the high temperature side condensing unit is fed with steam pressurized by the compressor. It is constituted by a lower block, and the low temperature side condensing part is a secondary side of the high temperature side condensing part, and is constituted by an upper block that comes into contact with the processing liquid sprayed from above. Organic waste liquid treatment equipment characterized by In the processing apparatus of the organic waste liquid of Claim 4 or Claim 5,
2. The organic waste liquid treatment apparatus according to claim 1, wherein the concentrator is configured to depressurize the inside of the evaporator to a predetermined pressure by a vacuum pump connected to the evaporator. For treatment liquids containing ammonia, ammonium salts, and moisture, such as digestive liquid that has been subjected to a certain treatment on organic waste liquid and its organic waste liquid, purified water with low ammonia concentration and high concentration ammonia water by condensing evaporated vapor In the processing method of organic waste liquid that is separated and removed,
A first evaporation step for evaporating the treatment liquid;
A second evaporation step of evaporating the residue that has not evaporated in the first evaporation step;
A first condensing step of condensing the vapor evaporated in the first evaporating step in two stages of high temperature side condensation and low temperature side condensation;
A second condensing step of condensing the vapor evaporated in the second evaporating step in two stages of high temperature side condensation and low temperature side condensation;
The distillate condensed on the high temperature side by the first condensing step and the distillate condensed on the low temperature side by the second condensing step are refluxed to the first evaporation step as a part of the processing liquid. A method for treating organic waste liquid. In the processing method of the organic waste liquid of Claim 7,
In the first evaporation step and the second evaporation step, the evaporation amount of the processing liquid evaporated in the second evaporation step is larger than the evaporation amount of the processing liquid evaporated in the first evaporation step. Waste liquid treatment method.

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