Liquid addition device and liquid addition method

Abstract

To provide a liquid addition device and liquid addition method high in durability by preventing corrosion of a pipe.SOLUTION: A liquid addition device 1 is equipped with a first pipe 11 through which slurry of a material to be processed 2 flows, and a second pipe 12 that flows a liquid 3 to be added to the material to be processed 2. The second pipe 12 has a smaller pipe diameter than the first pipe 11, and a tip of the second pipe 12 is connected to the first pipe 11 in a state where it is inserted inside the first pipe 11, and has a liquid addition unit 20 that adds the liquid 3 so as to encapsulate within the material to be processed 2 along a direction through which the material to be processed 2 flows within the first pipe 11, the liquid addition unit 20 being provided in the central area of the first pipe 11 in a cross-sectional view along the radial direction of the first pipe 11.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a liquid adding device and a liquid adding method that can be connected to a hydrothermal treatment reactor or the like. [Background technology]

[0002] 2. Description of the Related Art Conventionally, there has been known a liquid adding device that adds a second liquid to a first liquid to produce a dilute liquid (for example, see Patent Document 1).

[0003] Patent Document 1 describes a liquid addition device that adds a second liquid to the first liquid through a first pipe that flows a first liquid and a second pipe that is connected to the first pipe. The tip of the second pipe is inserted into the first pipe to a position approximately at the center of the inner diameter of the first pipe, so that a minute amount of the second liquid added to the first liquid is uniformly dispersed in the first pipe. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-163245 A Summary of the Invention [Problem to be solved by the invention]

[0005] In Patent Document 1, the second liquid added to the first liquid is uniformly dispersed in the first pipe, so that if the second liquid is, for example, a strong acid or strong alkali, the second liquid may come into contact with the inner wall of the first pipe, causing corrosion. Even if a small amount of the second liquid is added to the first liquid, it is not suitable for cases where the first liquid and the second liquid are not to be mixed before being transported to the next process. [Means for solving the problem]

[0006] SUMMARY OF THE PRESENT EMBODIMENTS Accordingly, an object of the present invention is to provide a liquid adding device and a liquid adding method which are highly durable and prevent corrosion of piping.

[0007] A characteristic configuration of the liquid addition device according to the present invention is that it comprises a first pipe through which a slurry-like material to be treated flows, and a second pipe through which a liquid to be added to the material to be treated flows, the second pipe having a smaller pipe diameter than the first pipe, and connected to the first pipe with a tip of the second pipe inserted inside the first pipe, and having a liquid addition section that adds the liquid so as to enclose it inside the material to be treated along the direction in which the material to be treated flows, and the liquid addition section is provided in a central region of the first pipe when viewed in a cross section along the radial direction of the first pipe.

[0008] In this configuration, a second pipe having a smaller pipe diameter than the first pipe through which the slurry-like material flows is connected to the first pipe with its tip inserted inside the first pipe, and the second pipe has a liquid adding section that adds liquid to the material along the flow direction of the material. The liquid adding section is provided in the central region of the first pipe in a cross-sectional view along the radial direction of the first pipe, so that liquid can be added to the central region of the first pipe. According to this configuration, the material to be treated flowing in the first pipe is in a slurry state and has a high viscosity relative to the liquid, so that the liquid added to the central region is unlikely to diffuse in the radial direction. Therefore, the liquid flows through the first pipe while covered by the material to be treated, so that the liquid can be transported to the next process while sealed inside the material to be treated without diffusing into the material to be treated.

[0009] Another characteristic feature is that the liquid is an acid or an alkali.

[0010] If the liquid is an acid or alkali, corrosion may occur when the liquid diffuses in the workpiece and comes into contact with the inner wall of the first pipe. According to this configuration, the liquid is added to the central region of the first pipe in a cross-sectional view along the radial direction of the first pipe, and flows through the first pipe covered with the slurry-like workpiece, so that the liquid does not come into contact with the inner wall of the first pipe. Therefore, even when a strong acid or strong alkali is added, it is possible to prevent corrosion of the first pipe. In addition, since the liquid does not diffuse into the workpiece, it is possible to transport the workpiece while suppressing the reaction between the liquid and the workpiece. This is useful when adding the liquid before the next process but not wanting the reaction to occur until the next process.

[0011] Another characteristic feature is that the device further includes a box-shaped structure that hermetically surrounds the connection portion of the first pipe and the second pipe and the first pipe and the second pipe adjacent to the connection portion.

[0012] By providing a box-shaped structure that hermetically surrounds the connection between the first and second pipes and the first and second pipes adjacent to the connection, if liquid leaks from the connection, it is possible to collect the liquid inside the box-shaped structure, thereby preventing the liquid from leaking outside the device, thereby protecting surrounding equipment and ensuring the safety of workers.

[0013] Another characteristic feature is that the box-shaped structure has a liquid level detector that detects the level of the liquid contained therein.

[0014] By having a liquid level detector that detects the liquid level inside the box-shaped structure, an alarm can be sounded if the leaked liquid reaches or exceeds a certain level, prompting inspection of the equipment, thereby protecting surrounding equipment and ensuring the safety of workers.

[0015] Another characteristic feature is that the first pipe has a temperature detection section downstream of the liquid addition section, which detects the temperature of the workpiece.

[0016] When liquid is added to the workpiece, the liquid reacts with the workpiece and generates heat. By detecting the temperature of the workpiece downstream of the liquid addition section, the progress of the reaction and the amount of liquid added to the workpiece can be confirmed.

[0017] Another characteristic feature is that the first pipe is positioned higher downstream from the liquid adding portion.

[0018] Since the slurry-like material to be treated flowing through the first pipe is pumped, if the first pipe is located higher downstream from the liquid addition section, the first pipe will be filled with the material to be treated or the liquid, and no gas phase will be generated in the first pipe. This increases the accuracy of the temperature detected by the temperature detection section, and allows a plug-in sensor to be used as the temperature detection section.

[0019] Another characteristic feature of the present invention is that the apparatus further comprises an alarm that issues an alarm when the temperature detected by the temperature detection section is outside a preset temperature range.

[0020] By issuing an alarm when the temperature of the workpiece measured by the temperature detection unit is lower than a preset temperature, the operator is notified that the amount of liquid added is too small, and the amount added can be adjusted. Also, by issuing an alarm when the temperature of the workpiece is higher than a preset temperature, the operator is notified that the amount of liquid added is too large, and the amount added can be adjusted.

[0021] Another characteristic feature is that the liquid supply device further includes an additive amount adjuster that adjusts the amount of the liquid added, and a control unit that controls the additive amount adjuster based on the temperature detected by the temperature detection unit.

[0022] By providing an addition amount adjuster and a control unit, the control unit can instruct the addition amount adjuster to increase or decrease the amount of liquid added based on the temperature detected by the temperature detection unit, making it possible to automatically adjust the amount of liquid added.

[0023] Another characteristic configuration is that the device further includes a memory unit that stores the temperature detected by the temperature detection unit, and a calculation unit that calculates the amount of temperature rise within a specified time from the temperature information stored in the memory unit, and the control unit controls the addition amount adjuster based on the amount of temperature rise.

[0024] By providing a memory unit and a calculation unit, the control unit can instruct the addition amount adjuster to increase or decrease the amount of liquid added based on the amount of temperature rise within a specified time, making it possible to adjust the amount of liquid added so that the temperature of the workpiece is constant. Also, since the amount of liquid added is adjusted based on the amount of temperature rise of the workpiece, it becomes possible to add an appropriate amount of liquid while suppressing temperature fluctuations of the workpiece, compared to when the amount of liquid added is adjusted based on the absolute temperature of the workpiece.

[0025] Another characteristic configuration is that the first pipe has a bent portion bent at a right angle, and the second pipe is connected to the first pipe at the bent portion.

[0026] By having the first pipe bent at a right angle, the degree of freedom in the arrangement of the first pipe can be improved, and the liquid addition device can be made compact. In addition, since the material to be treated is in a slurry state, even if the second pipe is connected to the first pipe at the bent part, the liquid added to the material to be treated does not spread in the radial direction of the first pipe. This makes it possible to improve the degree of freedom in the design of the liquid addition device.

[0027] Another characteristic feature is that the liquid addition section is an opening shaped by cutting the tip of the second pipe obliquely, and the opening is formed on the downstream side of the first pipe.

[0028] The liquid addition section is an opening shaped by cutting the tip of the second pipe at an angle, and the opening is located downstream in the first pipe, so that the liquid can be added along the direction of flow of the material to be treated. Therefore, the liquid flows in the same direction as the material to be treated, so there is no turbulence caused by crossing the flow of the material to be treated, and no diffusion occurs. Furthermore, since the opening is shaped by cutting the tip of the second pipe at an angle, the liquid addition section can be provided by simple processing.

[0029] Another characteristic configuration is that the second pipe inserted inside the first pipe is bent in an L shape toward the downstream side of the first pipe, and the liquid addition section is an opening provided at the tip of the second pipe.

[0030] The second pipe inserted inside the first pipe is bent in an L-shape toward the downstream side of the first pipe, and the liquid addition part is an opening provided at the tip of the second pipe, so that the liquid can be added along the flow direction of the workpiece. Therefore, since the liquid flows in the same direction as the workpiece, turbulence is not generated by intersecting with the flow of the workpiece, and diffusion does not occur. In addition, compared to an opening with a shape in which the tip of the second pipe is cut obliquely, the liquid is less likely to be added toward the radial direction of the first pipe, so that contact between the liquid and the inner wall of the first pipe can be more suppressed.

[0031] Another characteristic feature is that the first pipe is connected to a hydrothermal treatment reactor on the downstream side, the material to be treated is a slurry derived from biomass, and the liquid is sulfuric acid.

[0032] When sulfuric acid is added to a biomass-derived slurry and hydrothermal treatment is performed, the sulfuric acid functions as a catalyst for organic matter decomposition, which is the initial reaction of the hydrothermal treatment, and therefore the hydrothermal treatment reaction can proceed efficiently. Although sulfuric acid cannot be added directly to a hydrothermal treatment reactor due to its high temperature, sulfuric acid can be added to the hydrothermal treatment reactor by incorporating sulfuric acid into the material to be treated before it is put into the hydrothermal treatment reactor. The sulfuric acid added to the hydrothermal treatment reactor is mixed with the material to be treated and diffuses into the hydrothermal treatment reactor to react with the material to be treated, so that it is less likely to come into contact with the inner wall of the hydrothermal treatment reactor, and the risk of corrosion of the hydrothermal treatment reactor can be reduced.

[0033] Another characteristic feature is that the hydrothermal treatment reactor has an agitating blade, and the agitating blade performs agitation at a predetermined speed or less.

[0034] By having the hydrothermal treatment reactor have an agitator blade, the agitator blade can agitate the material to be treated in the hydrothermal treatment reactor, thereby increasing the reaction rate of the hydrothermal treatment. In addition, when high-speed agitation is performed, sulfuric acid diffuses into the material to be treated at once and comes into contact with the inner wall of the hydrothermal treatment reactor, increasing the risk of corrosion of the hydrothermal treatment reactor. Therefore, by performing slow agitation at a predetermined speed or less, the diffusion of sulfuric acid can be caused slowly, thereby reducing the risk of corrosion of the hydrothermal treatment reactor. Furthermore, it is possible to avoid the risk of the material to be treated put into the hydrothermal treatment reactor being short-circuited to the reactor outlet, so that it is possible to ensure a sufficient residence time for the material to be treated.

[0035] Another characteristic feature is that the hydrothermal treatment in the hydrothermal treatment reactor is carried out continuously.

[0036] When the hydrothermal treatment reaction is carried out by batch processing, the material to be treated is retained in the first pipe or the hydrothermal treatment reactor, and the sulfuric acid added inside the material to be treated diffuses and comes into contact with the inner wall of the first pipe, increasing the risk of corrosion. Therefore, by using a continuous treatment that does not cause retention, the risk of corrosion of the equipment can be reduced.

[0037] A feature of the liquid adding method of the present invention is that it is a liquid adding method for adding liquid to a slurry-like material to be treated flowing through a first pipe, and includes an adding step of adding the liquid in a central region of the first pipe in a cross-sectional view along the radial direction of the first pipe so as to enclose the liquid inside the material to be treated along the direction in which the material flows.

[0038] This method includes an adding step of adding liquid to the slurry-like material flowing through the first pipe in a central region of the first pipe in a cross-sectional view along the radial direction of the first pipe so as to enclose the liquid inside the material along the flow direction of the material. Since the material flowing through the first pipe is a highly viscous slurry, the added liquid is unlikely to diffuse in the radial direction, and the liquid flows through the first pipe covered by the material. Therefore, according to this method, it is possible to add the liquid so as to enclose the liquid inside the material without diffusing it into the material, and transport it to the next process.

[0039] Another feature is that the method includes a temperature detection step of detecting the temperature of the workpiece downstream of the confluence where the workpiece and the liquid confluence in the first pipe, and a control step of controlling the amount of the liquid added based on the temperature detected in the temperature detection step.

[0040] By including the temperature detection step and the control step as in this method, the control step can control the increase or decrease in the amount of liquid added based on the temperature detected in the temperature detection step, and the amount of liquid added can be automatically adjusted. Therefore, it is possible to add an appropriate amount of liquid according to the flow rate of the workpiece, etc.

[0041] Another feature is that the method includes a temperature detection step of detecting the temperature of the workpiece downstream of the confluence where the workpiece and the liquid confluence in the first pipe, a storage step of storing the temperature detected in the temperature detection step, a calculation step of calculating an amount of temperature rise within a specified time from the temperature information stored in the storage step, and a control step of controlling the amount of liquid added based on the amount of temperature rise.

[0042] By including a temperature detection step, a storage step, a calculation step, and a control step as in this method, the temperature detected in the temperature detection step is stored in the storage step, and the control step can control the increase or decrease in the amount of liquid added based on the amount of temperature rise within a predetermined time calculated in the calculation step, making it possible to adjust the amount of liquid added so that the temperature of the workpiece is kept constant. Therefore, the appropriate amount of liquid can be added more accurately. [Brief description of the drawings]

[0043] [Figure 1] FIG. 2 is a schematic diagram showing the configuration of a liquid adding device. [Diagram 2] FIG. 2 is a schematic diagram showing the configuration of a liquid adding device. [Diagram 3] 4 is a schematic diagram of a central region in a cross-sectional view along a radial direction of the first pipe. FIG. [Figure 4] FIG. 11 is a schematic diagram of a liquid addition section according to another embodiment. [Diagram 5] FIG. 11 is a schematic diagram of a liquid addition section according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0044] Hereinafter, an embodiment of the liquid adding device according to the present invention will be described with reference to the drawings. In this embodiment, as an example of the liquid adding device, it will be described as a device that adds concentrated sulfuric acid to a dehydrated cake, which is a processing object. However, the present invention is not limited to the following embodiment, and various modifications are possible within the scope of the gist of the present invention.

[0045] 1 is a schematic diagram of a liquid addition device 1 according to this embodiment. The liquid addition device 1 includes a first pipe 11, a second pipe 12, an addition amount adjuster 30, a hydrothermal treatment reactor 5, a control system 8, and an alarm device 9. The second pipe 12 is connected to the first pipe 11, and the first pipe 11 is connected to the hydrothermal treatment reactor 5 on the downstream side in the flow direction of the material to be treated 2. Hereinafter, the upstream side and downstream side of the first pipe 11 in the flow direction of the material to be treated 2 are also simply referred to as the upstream side and the downstream side.

[0046] A slurry-like material to be treated 2 flows through the first pipe 11. The material to be treated 2 is a dehydrated cake obtained after anaerobically treating organic waste. Examples of organic waste include sewage sludge, human waste sludge, agricultural village wastewater sludge, food waste such as kitchen garbage, lignocellulosic waste such as used paper and paper waste, agricultural residues, and livestock manure. These organic wastes may be treated individually or in combination. The material to be treated 2 may be a dehydrated cake obtained by dehydrating a mixture of anaerobically treated organic waste and organic waste that has not been anaerobically treated.

[0047] Anaerobic treatment is a biological treatment method in which organic waste is decomposed by the metabolic action of anaerobic microorganisms that grow in an anaerobic environment without oxygen. In this configuration, the dehydrated cake, which is the treated material 2, is dehydrated after being subjected to anaerobic treatment in a methane fermentation tank, for example, and then flows through the first pipe 11.

[0048] The moisture content of the workpiece 2 is, for example, 40 to 90%. Since the workpiece 2 contains solid matter, it exhibits physical properties different from those of a Newtonian fluid such as water, and has a large piping loss and high viscosity. The workpiece 2 in this embodiment has a viscosity of, for example, about 1 to 10 Pa·s, and flows in a laminar state through the first piping 11 by being pumped. The viscosity of the workpiece 2 varies depending on its type, composition, and moisture content, and is, for example, about 100 to 500 mPa·s, or about 5 to 15 kPa·s.

[0049] As shown in FIG. 2, the first pipe 11 is approximately horizontal near the confluence where the material 2 to be treated and the liquid 3 to be added to the material 2 to be treated are joined, and the position becomes higher toward the hydrothermal treatment reactor 5. That is, the hydrothermal treatment reactor 5 is disposed vertically above the confluence, and the first pipe 11 is connected to the hydrothermal treatment reactor 5 while bending in an arc toward the hydrothermal treatment reactor 5 after the confluence. The length of the first pipe 11 from the confluence to the hydrothermal treatment reactor 5 can be determined arbitrarily, but it is preferable that it is a relatively short distance, and for example, it is preferable that it is 1000 to 2000 mm when the pipe diameter is 100 to 200 mm. The first pipe 11 may be bent upward by bending processing, or may be formed by joining a substantially horizontal pipe and a bent pipe.

[0050] The second pipe 12 carries a liquid 3 to be added to the object 2. The liquid 3 may be an acidic or alkaline chemical, and is sulfuric acid in this embodiment. The sulfuric acid is added to improve the efficiency of the hydrothermal treatment in the hydrothermal treatment reactor 5, which will be described later.

[0051] The second pipe 12 has a smaller pipe diameter than the first pipe 11, and the pipe diameter of the second pipe 12 is, for example, 1 / 8 to 1 / 4 of the first pipe 11, and about 1 / 6 in this embodiment. The second pipe 12 is connected to the first pipe 11 with its tip inserted inside the first pipe 11. In this embodiment, the second pipe 12 is inserted vertically from above to below the first pipe 11. The connection part 13 where the first pipe 11 and the second pipe 12 are connected is formed by inserting the second pipe 12 into the first pipe 11 and then welding the periphery. Note that a branch pipe having the same pipe diameter as the second pipe 12 may be formed in the first pipe 11, and the second pipe 12 may be inserted into the branch pipe and then joined. The liquid 3 flowing through the second pipe 12 is supplied by an addition amount adjuster 30 (see FIG. 1). The addition amount adjuster 30 is composed of, for example, a pump such as a diaphragm pump and a valve. The liquid 3 is stored in a tank not shown.

[0052] The tip of the second pipe 12 is provided with a liquid addition section 20 for adding the liquid 3 to the first pipe 11. The liquid addition section 20 is an outlet for the liquid 3 flowing through the second pipe 12. In this embodiment, the liquid addition section 20 is an opening in a shape in which the tip of the second pipe 12 is cut obliquely, and is formed so that the cut end faces the downstream side. The cutting angle of the opening can be, for example, 30 to 60 degrees with respect to the central axis of the second pipe 12. If the cutting angle is 45 degrees or more, the liquid 3 is added toward the vertical downward side of the first pipe 11, increasing the risk of the liquid 3 coming into contact with the first pipe 11, so it is desirable that the cutting angle of the opening is 45 degrees or less. The tip of the second pipe 12 is inserted at a position approximately in the center with respect to the diameter of the first pipe 11, and the liquid addition section 20 is provided in the central region 11A of the first pipe 11. 3, the central region 11A of the first pipe 11 is a region along the central axis of the first pipe 11, occupying approximately 10% to 20% of the center of the first pipe 11 in a cross-sectional view along the radial direction of the first pipe 11. Therefore, when the liquid 3 is added to the workpiece 2 from the liquid adding section 20, the liquid 3 is added to the central region 11A.

[0053] Since the liquid adding section 20 is formed so that its opening faces the downstream side, the liquid 3 added to the object 2 flows along with the flow of the object 2. Therefore, the flow direction of the liquid 3 and the flow direction of the object 2 do not intersect to generate turbulence, and the liquid 3 added to the object 2 flows in a laminar flow state together with the object 2 inside the first piping 11.

[0054] The addition rate of liquid 3 is preferably about 1 to 2% of the object 2, that is, the flow rate of liquid 3 is preferably 1 / 50 to 1 / 100 of the flow rate of the object 2. Since the flow rate of the object 2 is much larger than that of liquid 3 and the object 2 flows through the first piping 11 in a laminar flow state, the liquid 3 added to the object 2 hardly diffuses into the object 2, and the liquid 3 flows downstream while remaining enclosed in the central region 11A.

[0055] The viscosity of the liquid 3 is, for example, 1 to 40 mPa·s. In general, it takes time for the liquid added to a slurry having a high viscosity to diffuse. Therefore, the liquid 3 flows downstream while being enclosed in the central region 11A without diffusing into the highly viscous object 2. Therefore, the object 2 can be transported to the hydrothermal treatment reactor 5 without diffusing the liquid 3 into the object 2, and it is possible to prevent the liquid 3 from contacting the inner wall of the first pipe 11. Furthermore, according to this embodiment, the liquid 3 hardly diffuses, so that the object 2 can be transported to the hydrothermal treatment reactor 5 without causing a reaction between the object 2 and the liquid 3. Therefore, it is possible to design the hydrothermal treatment reactor 5 so that the reaction between the object 2 and the liquid 3 occurs while the liquid 3 is added before the hydrothermal treatment reactor 5. Furthermore, the shorter the distance from the confluence of the workpiece 2 and the liquid 3 to the hydrothermal treatment reactor 5, the shorter the time it takes to transport the workpiece 2 containing the liquid 3 to the hydrothermal treatment reactor 5, and the more effectively the diffusion of the liquid 3 can be suppressed.

[0056] Acidic and alkaline chemicals such as sulfuric acid are highly reactive, and leakage is likely to cause corrosion of equipment or accidents. In this embodiment, as shown in FIG. 2, a box-shaped structure 6 is provided to prevent the leaked liquid 3 from leaking outside the liquid adding device 1. The box-shaped structure 6 hermetically surrounds the first pipe 11 and the second pipe 12 near the connection part 13 where the risk of leakage is high. The range surrounding the first pipe 11 and the second pipe 12 can be determined arbitrarily, and for example, a range of about 2 to 6 times the outer diameter of the first pipe 11 can be surrounded. The box-shaped structure 6 is preferably corrosion-resistant, and is preferably made of metal from the viewpoint of ease of manufacture. More specifically, it is preferable to use stainless steel such as SUS304 that has corrosion resistance. The connection parts of the box-shaped structure 6 and the first pipe 11 and the second pipe 12 are preferably sealed by welding. This blocks the internal space of the box-shaped structure 6 from the external space, and therefore it is possible to prevent the liquid 3 accumulated in the box-shaped structure 6 from leaking to the external space. The box-shaped structure 6 is not limited to a rectangular parallelepiped or a cube, and may be, for example, a cylindrical structure. Also, the box-shaped structure 6 is not limited to being made of metal, and may be made of a corrosion-resistant resin.

[0057] The box-shaped structure 6 has a liquid level detector 60 that detects the level of the liquid 3 that has leaked from the connection part 13 and accumulated inside the box-shaped structure 6. The liquid level detector 60 is provided vertically below the first pipe 11, for example, at a position 10 mm to 100 mm from the bottom surface of the box-shaped structure 6. The liquid adding device 1 may be equipped with an alarm that issues an alarm when leakage of the liquid 3 is detected by the liquid level detector 60. Moreover, the box-shaped structure 6 may have an acid leakage detection system that detects leaked acid instead of the liquid level detector 60.

[0058] The first pipe 11 has a temperature detector 7 for measuring the temperature of the workpiece 2 downstream of the junction where the workpiece 2 and the liquid 3 join. The temperature detector 7 is, for example, a plug-in contact thermometer, and directly measures the temperature of the workpiece 2. The thermometer is inserted inside the first pipe 11. When the workpiece 2 reacts with the liquid 3 (for example, sulfuric acid) added to the workpiece 2, the temperature of the workpiece 2 rises due to the heat of reaction. Therefore, if the temperature measured by the temperature detector 7 is less than a predetermined value, it can be determined that the amount of the liquid 3 added is insufficient, and if the temperature is equal to or greater than the predetermined value, it can be determined that the amount of the liquid 3 added is excessive. In this embodiment, the first pipe 11 is located higher from the junction toward the hydrothermal treatment reactor 5, so that no gas phase is generated in the first pipe 11, and the first pipe 11 is filled with the workpiece 2 and the liquid 3. Therefore, it is possible to reliably measure the temperature of the workpiece 2. The temperature detection unit 7 may be a non-contact thermometer, and the amount of liquid 3 added may be adjusted according to the temperature of the outer wall of the first pipe 11.

[0059] 1, the liquid adding device 1 in this embodiment includes a control system 8 that controls the addition amount adjuster 30 based on the temperature detected by the temperature detection unit 7. The control system 8 includes a memory unit 83 that stores the temperature detected by the temperature detection unit 7, a calculation unit 82 that calculates the amount of temperature rise within a predetermined time from the temperature information stored in the memory unit 83, and a control unit 81 that controls the addition amount adjuster 30 and the alarm device 9 based on the temperature or the amount of temperature rise.

[0060] Each functional unit of the control system 8 is constructed by hardware or software or both with a CPU as a core component. The control unit 81 controls the alarm device 9 to issue an alarm when the temperature measured by the temperature detection unit 7 is out of a predetermined value, and controls the addition amount adjuster 30 to increase or decrease the amount of the liquid 3 added. The addition amount adjuster 30 adjusts the amount of the liquid 3 added by driving a pump or opening or closing a valve in response to an instruction from the control unit 81. The predetermined temperature can be a value measured in advance as a reference temperature according to the components and flow rate of the workpiece 2. The components and flow rate of the workpiece 2 may be measured, for example, by a concentration meter or flow meter provided upstream of the connection unit 13.

[0061] The memory unit 83 stores the temperature detected by the temperature detection unit 7 at intervals of, for example, 10 seconds. The calculation unit 82 calculates the amount of temperature rise within a predetermined time (for example, 1 minute) using the temperature information stored in the memory unit 83. The control unit 81 controls the addition amount adjuster 30 to increase or decrease the amount of liquid 3 added when the amount of temperature rise is out of a preset reference value. The reference value can be a value obtained by measuring in advance the amount of temperature rise according to the components and flow rate of the workpiece 2 and the amount of liquid 3 added. By controlling the addition amount adjuster 30 based on the amount of temperature rise instead of the temperature, it is possible to suppress temperature fluctuations in the workpiece 2, and therefore it is possible to add an appropriate amount of liquid 3 to the workpiece 2.

[0062] The alarm device 9 may be provided in an operation room or the like of the liquid addition device 1. In this way, for example, the alarm device 9 can inform an operator in the operation room that the temperature or the amount of temperature increase is not within the appropriate range, thereby urging the operator to adjust the addition amount adjuster 30.

[0063] Next, the hydrothermal treatment reactor 5 will be described. The hydrothermal treatment reactor 5, which is connected to the first pipe 11 on the downstream side, is a device that performs hydrothermal treatment on the object to be treated 2. Hydrothermal treatment refers to a process in which the object to be treated 2 is carbonized by high-temperature and high-pressure treatment in a gas atmosphere that does not contain oxygen or has a low oxygen concentration, or in a state in which oxygen is blocked. The hydrothermal treatment reactor 5 has an agitator blade 50 for mixing and agitating the object to be treated 2 inside. The agitator blade 50 can be a flat paddle blade, an inclined paddle blade, a helical ribbon blade, or the like. Since the object to be treated 2 has high viscosity, the agitator blade 50 is preferably an anchor paddle blade. The hydrothermal treatment reactor 5 has an inlet at the bottom for introducing the object to be treated 2, and an outlet at the top for discharging the object to be treated 2 that has been subjected to hydrothermal treatment. Therefore, the object to be treated 2 is introduced from the bottom of the hydrothermal treatment reactor 5 and discharged from the top.

[0064] The material 2 to be treated becomes a carbonized sludge slurry by being hydrothermally treated. When the material 2 to be treated is mixed and stirred in the hydrothermal treatment reactor 5, the liquid 3 sealed inside the material 2 to be treated is diffused into the hydrothermal treatment reactor 5. The diffused liquid 3 reacts with the material 2 to be treated or the material 2 to be treated whose fluidity has been increased by the hydrothermal treatment, and functions as a catalyst for the decomposition of organic matter, which is the initial reaction of the hydrothermal treatment. At this time, it is preferable to stir the material 2 to be treated at a slow speed below a predetermined speed (for example, below 40 rpm). This is because strong stirring with a high peripheral speed increases the risk that sulfuric acid will come into contact with the inner wall of the hydrothermal treatment reactor 5 and cause corrosion. In addition, the material 2 to be treated introduced into the hydrothermal treatment reactor 5 is less likely to short-circuit to the discharge outlet, so it is possible to ensure the residence time required for the hydrothermal treatment.

[0065] The hydrothermal treatment according to the present embodiment is preferably carried out continuously, because if it is carried out in a batch manner, the object 2 to be treated will remain in the first piping 11, and the liquid 3 sealed inside the object 2 to be treated will diffuse and come into contact with the first piping 11, increasing the risk of corrosion.

[0066] Next, a liquid adding method for adding a liquid 3 to a workpiece 2 will be described with reference to Fig. 1. The liquid adding method according to this embodiment includes an adding step, a temperature detection step, a storage step, a calculation step, and a control step.

[0067] In the addition step, the liquid 3 is added from the liquid addition section 20 provided in the second pipe 12 to the workpiece 2 flowing in a laminar flow state through the first pipe 11. The amount of the liquid 3 added is adjusted by the addition amount adjuster 30, which is controlled by the control section 81. The liquid 3 added to the workpiece 2 is sealed in the central area 11A of the first pipe 11 through which the workpiece 2 flows, and is transported through the first pipe 11 to the hydrothermal treatment reactor 5. Since the flow rate and viscosity of the workpiece 2 relative to the liquid 3 are high, the liquid 3 is unlikely to diffuse into the workpiece 2. Therefore, the risk of the liquid 3 coming into contact with the inner wall of the first pipe 11 can be reduced, and the corrosion of the first pipe 11 can be prevented. In addition, since the reaction between the workpiece 2 and the liquid 3 can be suppressed, it is possible to design the hydrothermal treatment reactor 5 so that the reaction between the workpiece 2 and the liquid 3 occurs in the hydrothermal treatment reactor 5 while adding the liquid 3 before the hydrothermal treatment reactor 5.

[0068] Meanwhile, heat is generated by reaction at the contact point between the workpiece 2 and the liquid 3. In the temperature detection process, the temperature detection unit 7 detects the temperature of the workpiece 2. Since the temperature detection unit 7 is provided downstream of the junction where the workpiece 2 and the liquid 3 join, the temperature detection unit 7 detects the temperature of the workpiece 2 whose temperature has increased due to the addition of the liquid 3. The temperature of the workpiece 2 detected in the temperature detection process is stored by the memory unit 83 in the storage process. The memory unit 83 stores the temperature detected in the temperature detection process at intervals of, for example, 10 seconds. Then, in the calculation process, the calculation unit 82 calculates the amount of temperature increase within a predetermined time (for example, 1 minute) using the temperature information stored in the memory unit 83.

[0069] In the control step, the control unit 81 controls the addition amount adjuster 30 based on the temperature detected in the temperature detection step or the amount of temperature rise calculated in the calculation step. For example, when the temperature detected in the temperature detection step is out of a preset value, the control unit 81 controls the addition amount adjuster 30 to increase or decrease the amount of liquid 3 added. Alternatively, for example, when the amount of temperature rise is out of a preset reference value, the control unit 81 controls the addition amount adjuster 30 to increase or decrease the amount of liquid 3 added, and the addition step is performed. Note that in the control step, the control unit 81 may activate the alarm device 9 based on the temperature detected in the temperature detection step or the amount of temperature rise calculated in the calculation step.

[0070] In this way, by adding liquid 3 so that the temperature detected by temperature detection unit 7 becomes constant, it is possible to add an appropriate amount of liquid 3 and also to suppress corrosion of the inner wall of first piping 11 that occurs when liquid 3 diffuses inside workpiece 2 and comes into contact with first piping 11. Therefore, this is a liquid adding method that makes it possible to add an acid or alkali as liquid 3.

[0071] Other embodiments (1) As shown in Fig. 4, the liquid adding part 20 may be an opening provided on the side surface of the second pipe 12 and downstream of the first pipe 11. By providing the liquid adding part 20 on the side surface of the tip side of the second pipe 12, the added liquid 3 is added along the flow direction of the workpiece 2, so that turbulence is not generated and diffusion of the liquid 3 is further suppressed. In addition, the liquid 3 is not added toward the vertical downward side of the first pipe 11, so that the risk of the liquid 3 adhering to the inner wall of the first pipe 11 can be reduced.

[0072] (2) As shown in Fig. 5, the second pipe 12 inserted inside the first pipe 11 may be bent into an L-shape toward the downstream of the first pipe 11, and the liquid adding part 20 may be an opening provided at the tip of the second pipe 12. As a result, the liquid 3 is added along the flow direction of the workpiece 2, so that turbulence is not generated and the diffusion of the liquid 3 is further suppressed. In addition, the liquid 3 is not added toward the vertical downward side of the first pipe 11, so that the risk of the liquid 3 adhering to the inner wall of the first pipe 11 can be reduced.

[0073] (3) In the above embodiment, in the connection part 13 between the first pipe 11 and the second pipe 12, the first pipe 11 is approximately horizontal and the second pipe 12 is inserted from above the first pipe 11. However, the first pipe 11 does not have to be approximately horizontal. In addition, the first pipe 11 may have a curved part that is curved at a right angle in a plan view or a side view, and the second pipe 12 may be connected to the first pipe 11 at the curved part. Here, a right angle means 80 degrees to 100 degrees. Furthermore, the second pipe 12 does not have to be inserted from above. As long as the liquid addition part 20 is formed on the downstream side of the second pipe 12, the liquid 3 can be added along the flow of the object to be treated 2, so the positional relationship between the first pipe 11 and the second pipe 12 in the connection part 13 does not matter.

[0074] (4) The control unit 81 may control the addition amount adjuster 30 according to the necessary amount of the liquid 3 added, which is calculated from the concentration and flow rate of the workpiece 2. In this case, the memory unit 83 stores the concentration and flow rate of the workpiece 2 measured by a concentration meter and a flow meter provided upstream of the connection unit 13. The calculation unit 82 calculates the necessary amount of the liquid 3 added from this information and the target temperature, etc. The control unit 81 controls the addition amount adjuster 30 based on the necessary amount of the liquid 3 added calculated by the calculation unit 82. The calculation unit 82 may calculate the difference between the temperature detected by the temperature detection unit 7 and the target temperature, or may change the calculation method of the necessary amount of the liquid 3 added so that the difference becomes smaller. This makes it possible to automatically control the amount of the liquid 3 added according to the flow rate of the workpiece 2, etc. [Industrial Applicability]

[0075] INDUSTRIAL APPLICABILITY The present invention can be used in a liquid adding device that adds liquid to a slurry-like fluid. [Explanation of symbols]

[0076] 1:Liquid addition device 11:First piping 11A: Central area 12:Second piping 13: Connection part 2: Workpiece 20:Liquid addition section 3:Liquid 30: Addition amount adjuster 5: Hydrothermal treatment reactor 6: Box-like structure 60: Liquid level detector 7: Temperature detection section 81: Control section 82: Calculation section 83: Storage section 9:Alarm device

Claims

1. A first pipe through which a slurry-like material to be treated flows; A second pipe for flowing a liquid to be added to the object to be treated, The second piping is A pipe diameter is smaller than that of the first pipe, The second pipe is connected to the first pipe in a state where a tip end of the second pipe is inserted into the first pipe, a liquid adding section that adds the liquid so as to enclose the liquid inside the object to be treated along a flow direction of the object to be treated in the first pipe, The liquid addition section is a liquid addition device provided in a central region of the first pipe in a cross-sectional view taken along a radial direction of the first pipe.

2. 2. The liquid adding device according to claim 1, wherein the liquid is an acid or an alkali.

3. The liquid adding device according to claim 1 or 2, further comprising a box-shaped structure hermetically surrounding a connection portion between the first pipe and the second pipe and the first pipe and the second pipe adjacent to the connection portion.

4. The liquid adding device according to claim 3 , wherein the box-shaped structure has a liquid level detector for detecting the level of the liquid contained therein.

5. 3. The liquid adding device according to claim 1, wherein the first pipe has a temperature detection section downstream of the liquid adding section, the temperature detection section detecting a temperature of the workpiece.

6. The liquid adding device according to claim 5 , wherein the first pipe is positioned higher downstream from the liquid adding portion.

7. 6. The liquid adding device according to claim 5, further comprising an alarm that issues an alarm when the temperature detected by the temperature detection unit is outside a preset temperature range.

8. An additive amount adjuster for adjusting the additive amount of the liquid; The liquid adding device according to claim 5 , further comprising a control unit that controls the adding amount adjuster based on the temperature detected by the temperature detection unit.

9. A storage unit that stores the temperature detected by the temperature detection unit; A calculation unit that calculates an amount of temperature rise within a predetermined time from the temperature information stored in the storage unit, The liquid adding device according to claim 8 , wherein the control unit controls the adding amount regulator based on the amount of increase.

10. The first pipe has a curved portion curved at a right angle, The liquid adding device according to claim 1 or 2, wherein the second pipe is connected to the first pipe at the curved portion.

11. 3. The liquid adding device according to claim 1, wherein the liquid adding portion is an opening formed by cutting a tip of the second pipe at an angle, the opening being formed on a downstream side of the first pipe.

12. The second pipe inserted into the first pipe is bent in an L shape toward a downstream side of the first pipe, The liquid adding device according to claim 1 or 2, wherein the liquid adding portion is an opening provided at a tip of the second pipe.

13. The first pipe is connected to a hydrothermal treatment reactor on the downstream side, The material to be treated is a slurry derived from biomass, 2. The liquid adding device according to claim 1, wherein the liquid is sulfuric acid.

14. The hydrothermal treatment reactor has an agitator blade, The liquid adding device according to claim 13, wherein the stirring blade performs stirring at a predetermined speed or less.

15. 15. The liquid adding device according to claim 13 or 14, wherein the hydrothermal treatment in the hydrothermal treatment reactor is carried out continuously.

16. A liquid adding method for adding a liquid to a slurry-like material to be treated flowing through a first pipe, comprising: A liquid adding method comprising: an adding step of adding the liquid in a central region of the first pipe in a cross-sectional view along a radial direction of the first pipe so as to seal the liquid inside the workpiece along a flow direction of the workpiece.

17. a temperature detection step of detecting a temperature of the object to be treated downstream of a junction where the object to be treated and the liquid join in the first pipe; The liquid adding method according to claim 16, further comprising a control step of controlling an amount of the liquid added based on the temperature detected in the temperature detection step.

18. a temperature detection step of detecting a temperature of the object to be treated downstream of a junction where the object to be treated and the liquid join in the first pipe; a storage step of storing the temperature detected in the temperature detection step; a calculation step of calculating an amount of temperature rise within a predetermined time from the temperature information stored in the storage step; The liquid adding method according to claim 16, further comprising a control step of controlling an amount of the liquid added based on the amount of increase.

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