JP2013176712A - Fluid purification device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluid purification device capable of making an inner cylinder 22 and an outer cylinder 22 less in fatigue due to thermal expansion and shrinkage than before.SOLUTION: A fluid purification device includes: an inflow pipe 26 which has a double structure, in which an inner cylinder 22 is arranged inside an outer cylinder 21, and has its tip portion inserted into the inner cylinder 22 along its longitudinal direction so as to let waste water W flow in the inner cylinder 22; and a reaction tank 20 in which the waste water W is purified by subjecting organic matter in the waste water W to oxidative decomposition while an oxidizer introduced into an inter-cylinder space is mixed with the waste water W in the inner cylinder 22 after made to flow in the inner cylinder 22 from a tip opening of the inner cylinder 22 and the obtained mixed fluid is heated and pressurized. The fluid purification device is provided with a plurality of fluid discharge ports 26a arranged side by side along a longitudinal direction of the inflow pipe 26 at a tip portion of the inflow pipe 26.

Description

  The present invention relates to a fluid purification device that purifies a purification target fluid by oxidizing and decomposing the organic substance in the purification target fluid while pressurizing and heating a mixed fluid of the purification target fluid containing an organic substance and an oxidizing agent.

  Conventionally, as a method for purifying wastewater such as human waste, sewage, settlement wastewater, livestock manure, food factory wastewater, a method of performing biological treatment using activated sludge has been generally used. However, with this method, it has been impossible to treat high-concentration organic solvent wastewater that hinders the activity of microorganisms in activated sludge at the same concentration or wastewater containing plastic fine particles that cannot be biodegraded. In addition, wastewater containing a large amount of organic suspended solids (Suspended Solids) increases activated sludge, which increases costs due to increased aeration and excess sludge treatment. It had to be removed by physicochemical treatment such as coagulation sedimentation.

  On the other hand, in recent years, development of fluid purification devices that purify wastewater by oxidizing and decomposing organic matter in the mixed fluid while heating and pressurizing the mixed fluid of wastewater and oxidant such as air has been performed. In this type of fluid purification device, the organic substance in the mixed fluid is chemically oxidized and decomposed by heating and pressurizing the mixed fluid of the wastewater and the oxidizing agent in the reaction tank. In such oxidative decomposition, it is possible to purify even high-concentration organic solvent wastewater and plastic fine particle-containing wastewater that were impossible with biological treatment. In addition, even wastewater containing a large amount of organic suspended solids can be decomposed almost completely into oxidatively decomposed water, nitrogen gas, and carbon dioxide. .

  As a reaction tank in such a fluid purification apparatus, a pressure balance type reaction tank described in Patent Document 1 is known. As shown in FIG. 1, the pressure balance type reaction tank 900 has a double cylinder structure including a cylindrical outer cylindrical body 901 and a cylindrical reaction vessel 902 disposed inside the cylindrical outer cylindrical body 901. ing. The outer cylindrical body 901 is made of a stainless material that is sufficiently thick to withstand high pressure. The reaction vessel 902 is made of a corrosion-resistant nickel alloy. On the lower lid of the outer cylindrical body 901, an air supply pipe 903 for pressure-feeding air as an oxidant into an inter-cylinder space formed between the outer cylindrical body 901 and the reaction vessel 902 inside the outer cylindrical body 901. Has penetrated. The reaction vessel 902 is cantilevered by the lower lid in a state where the lower end of the reaction vessel 902 penetrates the lower lid of the outer cylindrical body 901. A through-hole 902 a for receiving the inflow pipe 904 is formed in the upper end wall of the reaction vessel on the free end side of the reaction vessel 902. On the inner side of the outer cylindrical body 901, the end of the inflow pipe 904 that penetrates the outer cylindrical body upper cover from the outer side of the outer cylindrical body 901 and enters the outer cylindrical body 901 is provided on the upper end wall of the reaction vessel 902. It enters the inside of the reaction vessel 902 through the through-hole 902a. Wastewater pumped through the inflow pipe 904 flows into the reaction vessel 902 and then moves in the reaction vessel 902 from the upper side of the outer cylindrical body toward the lower side of the outer cylindrical body.

  In the pressure balance type reaction tank 900 having such a configuration, air as an oxidant moves as follows. In other words, the air pressure-fed into the inter-cylinder space between the outer cylindrical body 901 and the reaction vessel 902 via the air supply pipe 903 provided on the lower lid of the outer cylindrical body 901 moves downward in the inter-cylinder space. From the top to the top of the outer cylinder 901. In the vicinity of the upper lid, a gap is formed between a through port 902a provided in the upper end wall of the reaction vessel 902 and an inflow pipe 904 having a smaller diameter than the through port 902a. The inter-cylinder space between the outer cylindrical body 901 and the reaction vessel 902 communicates with the space inside the reaction vessel 902 through the gap. In the inter-cylinder space, the air that has moved to the vicinity of the upper lid of the outer cylindrical body 901 flows into the reaction vessel 902 through the gap between the through-hole 902a and the inflow pipe 904, and is then mixed with the waste water. It moves in the direction 902 from the upper side to the lower side.

  Since the inter-cylinder space between the outer cylindrical body 901 and the reaction vessel 902 and the reaction vessel 902 communicate with each other, the mixed fluid of the atmospheric pressure in the inter-cylinder space and the air and waste water in the reaction vessel 902 The pressure is almost the same. For this reason, a large pressure can be applied to the mixed fluid in the reaction vessel 902 without generating a pressure difference between the inside and outside of the reaction vessel 902. As a result, the reaction vessel 902 made of an expensive nickel alloy can be made into a non-breakdown pressure specification with a small thickness, and cost reduction can be realized.

  However, this pressure balance type reaction tank 900 has a problem that, in the entire region in the longitudinal direction of the reaction vessel 902, the region near the tip of the inflow pipe 904 becomes particularly hot, and metal fatigue due to expansion and contraction tends to occur. Specifically, in the vicinity of the tip of the inflow pipe 904, the organic matter mixed with air is heated and pressurized, and heat is generated as it is rapidly oxidized and decomposed. If the organic matter concentration in the wastewater is high, heat generated by the oxidative decomposition of organic matter occurs in a large amount and in the vicinity of the inflow pipe 904, so that the mixed fluid in the vicinity of the inflow pipe 904 becomes very hot. As a result, the region near the tip of the inflow pipe in the reaction vessel 902 becomes particularly hot. For the same reason, even in the outer cylindrical body 901, the region near the tip of the inflow pipe becomes particularly hot and easily causes metal fatigue.

  The present invention has been made in view of the above background, and the object of the present invention is to prevent fatigue caused by thermal expansion and contraction of the inner cylinder (for example, the reaction vessel 902) and the outer cylinder (for example, the outer cylinder 901). It is providing the fluid purification apparatus which can be suppressed more.

  In order to achieve the above object, the present invention comprises a dual structure in which a cylindrical inner cylinder is disposed inside a cylindrical outer cylinder, and a fluid to be purified is placed inside the inner cylinder. An in-cylinder space between the outer tube and the inner tube, and an inflow tube in which its tip is inserted along the longitudinal direction of the inner tube with respect to the inner tube in order to flow in An oxidant introduction port provided in the outer cylinder for introduction into the inner cylinder, and an opening provided in a region on the rear end side of the front end of the inflow pipe in the entire area in the longitudinal direction of the inner cylinder. And an oxidant introduced into the inter-cylinder space is allowed to flow into the inner cylinder through the opening, and then mixed with a purification target fluid inside the inner cylinder, and the obtained mixed fluid The reaction to purify the fluid to be purified by decomposing organic matter in the fluid to be purified by oxidation reaction while heating and pressurizing The fluid purifying apparatus comprising a plurality of fluid outlets arranged along the longitudinal direction of the inlet pipe, is characterized in that provided in the front end portion of the inlet pipe.

  In the present invention, the purification target fluid in the inflow pipe is discharged from the plurality of fluid discharge ports provided at the distal end portion of the inflow pipe to the inside of the inner cylinder and mixed with the oxidant. These fluid discharge ports are arranged along the longitudinal direction of the inflow pipe, and the longitudinal direction of the inflow pipe is along the longitudinal direction of the inner cylinder. For this reason, in the longitudinal direction of the inner cylinder, rapid oxidative decomposition of the organic matter in the purification target fluid occurs in the vicinity of a plurality of different fluid discharge ports. In this way, by dispersing a plurality of positions in the longitudinal direction of the inner cylinder that cause rapid oxidative degradation of organic matter, compared to the conventional case where rapid oxidative degradation of organic matter occurs at only one position in the longitudinal direction. Thus, local heat generation of the inner cylinder can be suppressed, and fatigue due to thermal expansion and contraction of the inner cylinder and the outer cylinder can be suppressed.

The schematic block diagram which shows the pressure balance type reaction tank of patent document 1. FIG. The schematic block diagram which shows the fluid purification apparatus which concerns on embodiment. The perspective view which shows the inner cylinder of the reaction tank of the fluid purification apparatus. The longitudinal cross-sectional view which shows the reaction tank. The cross-sectional view which shows the inflow pipe of the reaction tank. The cross-sectional view which shows the inner cylinder with the inflow pipe. The longitudinal cross-sectional view which shows the inner cylinder and inflow pipe | tube of a vertical reaction tank in the fluid purification apparatus which concerns on a modification.

Hereinafter, an embodiment of a fluid purification apparatus to which the present invention is applied will be described.
First, a basic configuration of the fluid purification device according to the embodiment will be described. FIG. 2 is a schematic configuration diagram illustrating a fluid purification device according to the embodiment. The fluid purification device according to the embodiment includes a raw water tank 1, a stirrer 2, a raw water supply pump 3, a raw water pressure gauge 4, a raw water inlet valve 5, an oxidant pressure feed pump 6, an oxidant pressure gauge 7, an oxidant inlet valve 8, and heat. It includes an exchanger 9, a heat medium tank 10, a heat exchange pump 11, an outlet pressure gauge 12, an outlet valve 13, a gas-liquid separator 14, a reaction tank 20, a control unit (not shown), and the like.

  The control unit individually corresponds to a power feeding circuit composed of a combination of an earth leakage breaker, a magnet switch, a thermal relay, and the like to each of the agitator 2, the raw water supply pump 3, the oxidant pressure feed pump 6, the oxidant pressure feed pump 6, and the heat exchange pump 11. Have as much as you want. And the on / off of the power supply with respect to these apparatuses is controlled separately by turning on / off the magnet switch of a feed circuit with the control signal from a programmable sequencer.

  The raw water pressure gauge 4, the oxidant pressure gauge 7, and the outlet pressure gauge 12 each output a voltage having a value corresponding to the pressure detection result. Moreover, the thermometer 24 of the reaction vessel 20 outputs a voltage corresponding to the temperature detection result. The voltages output from these measuring devices are individually converted into digital data by an A / D converter (not shown) and then input to the programmable sequencer as sensing data. The programmable sequencer controls driving of various devices based on the sensing data.

  In the raw water tank 1, waste water W containing an organic substance having a relatively large molecular weight is stored in an untreated state. The waste water W is composed of at least one of organic solvent waste water, paper making waste water generated in the paper manufacturing process, and toner manufacturing waste water generated in the toner manufacturing process. Papermaking wastewater and toner manufacturing wastewater may contain persistent organic substances.

  The stirrer 2 stirs the wastewater W as the purification target fluid to uniformly disperse suspended solids contained in the wastewater, thereby achieving a uniform organic substance concentration. The waste water W in the raw water tank 1 is continuously pumped by a raw water supply pump 3 composed of a high pressure pump, and flows into the reaction tank 20 through the raw water inlet valve 5 at a high pressure. The raw water inlet valve 5 plays the role of a check valve and allows the waste water W pumped from the raw water supply pump 3 to flow from the raw water supply pump 3 side to the reaction tank 20 side described later, Prevent reverse flow.

  The reaction tank 20 has a double cylinder structure including an outer cylinder 21 and an inner cylinder 22 disposed inside the reaction cylinder 20. The waste water W that has passed through the raw water inlet valve 5 flows into the inner cylinder 22 of the reaction tank 20 through an inflow pipe (26 in FIG. 3) described later.

  The inflow pressure of the waste water W due to the driving of the raw water supply pump 3 is detected by the raw water pressure gauge 4 disposed on the upstream side of the raw water inlet valve 5 and input as sensing data to the programmable sequencer of the control unit. The inflow pressure of the waste water W when the raw water supply pump 3 is driven and the pressure in the inner cylinder 22 are substantially the same. The programmable sequencer determines whether the pressure in the inner cylinder 22 is appropriate based on the detection result of the pressure sent from the raw water pressure gauge 4 when the raw water supply pump 3 is being driven.

  The oxidant pressure feed pump 6 composed of a compressor sends air taken in as an oxidant to the reaction tank 20 through the oxidant inlet valve 8 while compressing the air to a pressure similar to the inflow pressure of the waste water W. The oxidant inlet valve 8 plays the role of a check valve, and allows the air fed from the oxidant pressure feed pump 6 to flow from the oxidant pressure feed pump 6 side to the reaction tank 20 side, Prevent reverse flow.

  The air pumped into the reaction tank 20 enters the inter-cylinder space between the outer cylinder 21 and the inner cylinder 22 and then flows into the vicinity of the longitudinal inlet of the inner cylinder 22. And it mixes with the waste water W sent in the inner cylinder 22 by the inflow pipe, and turns into a mixed fluid.

  The inflow pressure of the air generated by driving the oxidant pump 6 is detected by an oxidant pressure gauge 7 disposed upstream of the oxidant inlet valve 8 and input as sensing data to a programmable sequencer of the control unit. . The inflow pressure of air when the oxidant pressure gauge 7 is driven and the pressure in the reaction tank 20 are substantially the same. The programmable sequencer determines whether or not the pressure in the reaction vessel 20 is appropriate based on the detection result of the pressure sent from the oxidant pressure gauge 7 when the oxidant pressure feed pump 6 is being driven.

  The amount of air pumped by driving the oxidant pump 6 is determined based on the stoichiometric amount of oxygen necessary to completely oxidize the organic matter in the wastewater. More specifically, COD (Chemical Oxygen Demand) of wastewater, total nitrogen (TN), total phosphorus (TP), etc. are necessary for complete oxidation of organic matter based on organic matter concentration, nitrogen concentration, phosphorus concentration, etc. in wastewater W The amount of oxygen is calculated, and the pumping amount of air is set based on the result.

  The inflow of air is set by the worker, but the type of organic matter contained in the wastewater W is stable over time, and the physical properties such as turbidity, light transmittance, electrical conductivity, specific gravity, etc. When the correlation with the amount of oxygen is relatively good, the programmable sequencer is configured to perform the process of automatically correcting the above-mentioned control range based on the result of detecting the physical property by a sensor or the like. May be.

  As the oxidizing agent, in addition to air, any one of oxygen gas, ozone gas, hydrogen peroxide water, or a mixture of two or more of them can be used. From the viewpoint of suppressing the release of heat from the inner cylinder 22, it is preferable to use a gas such as air, oxygen gas, or ozone gas. This is because the gas has a lower thermal conductivity than the liquid, so that the gas can function as a heat insulating material by filling the space between the cylinders with the gas.

  As shown in FIG. 3, a heater 23 for heating the mixed fluid in the inner cylinder 22 is wound around the outer surface of the inner cylinder 22. In FIG. 2, the mixed fluid in the inner cylinder 22 is heated by the heater 23, and the temperature is also raised by heat generated by oxidative decomposition of the organic matter. When the wastewater W contains organic matter at a high concentration, the mixed fluid may be heated to a desired temperature only by a large amount of heat generated when a large amount of organic matter is decomposed by oxidation. In this case, heating by the heater 23 is performed only when the apparatus is started up, and the power supply to the heater 23 can be turned off after the oxidative decomposition is started.

  Examples of the pressure applied to the mixed fluid in the inner cylinder 22 include a range of 0.5 to 30 Mpa (desirably 5 to 30 Mpa). The pressure in the inner cylinder 22 is adjusted by an outlet valve 13 described later. When the pressure in the inner cylinder 22 becomes higher than the threshold value, the outlet valve 13 automatically opens the valve and discharges the fluid mixture in the inner cylinder 22 to the outside, thereby maintaining the pressure in the inner cylinder 22 near the threshold value. To do.

  Examples of the temperature of the mixed fluid in the inner cylinder 22 include 100 to 700 ° C. (desirably 200 to 550 ° C.). The temperature is adjusted by turning on and off the heater described above. When a heat exchanger is also provided on the outer peripheral surface of the outer cylinder 21, the temperature of the mixed fluid in the inner cylinder 22 can be adjusted also by turning on / off the heat exchanger.

  When temperature = 374.2 ° C. or higher and pressure = 21.8 MPa or higher are adopted as temperature and pressure conditions, the critical temperature and critical pressure of water are exceeded, and the critical temperature and critical pressure of air are also exceeded. In this state, the mixed fluid becomes a supercritical fluid having an intermediate property between liquid and gas. In such a supercritical fluid, the organic matter is well dissolved in the supercritical fluid and is in good contact with air, so that the oxidative decomposition of the organic matter proceeds rapidly.

  As a condition of temperature and pressure, a relatively high pressure of temperature = 200 ° C. or higher (preferably 374.2 ° C. or higher) and pressure = 21.8 MPa (preferably 10 MPa or higher) is adopted. The waste water in the mixed fluid may be converted into high-temperature and high-pressure steam.

  In the inner cylinder 22, the mixed fluid is brought into a high temperature and high pressure state to promote oxidative decomposition of organic matter and ammonia nitrogen in the mixed fluid. The mixed fluid obtained by oxidizing and decomposing organic matter and ammonia nitrogen is discharged from the reaction tank 20. Then, after being cooled rapidly, after being depressurized by the outlet valve 113, it is separated into liquid and gas by the gas-liquid separator 114.

  FIG. 4 is a longitudinal sectional view showing the reaction tank 20. The inner cylinder 22 is a cylinder made of acid-resistant titanium (Ti). Instead of titanium, one made of Ta, Au, Pt, Ir, Rh, or Pd may be used. Moreover, you may use what consists of an alloy containing at least any one among Ti, Ta, Au, Pt, Ir, Rh, and Pd.

  The outer cylinder 23 is a cylinder made of a metal material having excellent strength, such as stainless steel (SUS304, SUS316), Inconel 625, and the like. The pressure inside the reaction tank 20 is controlled to a high pressure of 0.5 to 30 Mpa, desirably 5 to 30 Mpa. The outer cylinder 23 is thick so that it can withstand such a high pressure. On the other hand, since the inner cylinder 22 is required to have corrosion resistance rather than pressure resistance, titanium that exhibits excellent corrosion resistance is adopted as a material.

  Waste water W pumped toward the reaction tank 20 by the raw water supply pump (3 in FIG. 2) passes through the raw water inlet valve (5 in FIG. 2) and then is connected to the outlet side of the raw water inlet valve. Enter the tube 15. The feed pipe 15 is connected to an inflow pipe 26 provided on the inlet side of the reaction tank 20 by an inlet joint 17. The waste water W pumped from the feed pipe 15 into the reaction tank 20 flows into the inner cylinder 22 through the inflow pipe 26 in the reaction tank 20. Then, it moves from the left side to the right side in the drawing along the longitudinal direction in the inner cylinder 20.

  On the other hand, the air A pumped into the reaction tank 20 by the oxidant introduction pump (6 in FIG. 2) flows into the inter-cylinder space between the outer cylinder 21 and the inner cylinder 22. Then, the inter-cylinder space moves from the right side to the left side in the drawing along the longitudinal direction. The inner cylinder 22 has a tip opening at the end on the left side in the figure, centered on the center line of the cylinder cross section and having the same diameter as the cylinder inner diameter. The distal end portion of the inflow pipe 26 for allowing the waste water W to flow into the inner cylinder 22 is inserted into the inner cylinder 22 through the distal end opening. Since the outer diameter of the distal end portion of the inflow pipe 26 is much smaller than the inner diameter of the inner cylinder 22, the inner cylinder 22 is provided between the outer peripheral surface of the inflow pipe 26 and the inner peripheral surface of the inner cylinder 22. A gap is formed. The air A that has moved to the left end of the inter-cylinder space between the outer cylinder 21 and the inner cylinder 22 turns to the left in the figure than the inner cylinder 22 and then passes through the gap into the inner cylinder 22. enter in.

  The inside of the inner cylinder 22 is at a high temperature in addition to the high pressure. The temperature is 100 to 700 ° C, desirably 200 to 550 ° C. When the operation of the fluid purification device is started, the mixed fluid of the waste water W and the air A in the inner cylinder 22 is under pressure, but the temperature is not so high. Therefore, at the start of operation, the programmable sequencer causes the heater (23 in FIG. 3) to generate heat, and raises the temperature of the mixed fluid in the inner cylinder 22 to 200 to 550 ° C.

  When the oxidative decomposition of the organic substance is started in the inner cylinder 22 and the temperature of the mixed fluid in the inner cylinder 22 is maintained at a high temperature, the inner cylinder 22 and the outer cylinder 21 are in the inter-cylinder space. Air A traveling from the right side to the left side in the figure while contacting the outer peripheral surface of the cylinder 22 and the heater (23) flows into the inner cylinder 22 while being preheated by heat conduction from the outer peripheral surface of the inner cylinder 22 and the heater. It becomes like this.

  In the inner cylinder 22, hydrochloric acid derived from a chloro group of organic chloride and sulfuric acid derived from a sulfonyl group such as an amino acid may be generated, and the inner wall of the inner cylinder 22 may be placed under strong acidity. For this reason, a cylinder made of titanium having excellent corrosion resistance is adopted as the inner cylinder 22. However, since titanium is a very expensive material, if the thickness of the inner cylinder 22 is increased to a value that can withstand high pressure, the cost becomes very high. Therefore, the outer cylinder 21 is disposed outside the inner cylinder 22, and the required pressure resistance is exhibited by the outer cylinder 21 made of stainless steel or the like that is cheaper than titanium. Since the pressure in the inter-cylinder space between the inner cylinder 22 and the outer cylinder 21 becomes almost the same value as the pressure in the inner cylinder 22 by the air A being pumped, for the inner cylinder 22 made of thin titanium, A large pressure is not applied.

  The mixed fluid (W + A) that has moved to the vicinity of the right end of the inner cylinder 22 in the drawing is in a state in which organic substances and inorganic compounds are almost completely oxidized and decomposed. A conveyance pipe 16 for conveying the mixed fluid purified in the inner cylinder 22 is connected to the downstream end of the inner cylinder 22 in the fluid conveyance direction via an outlet joint 18. The mixed fluid purified by the oxidative decomposition of the organic matter enters the transport pipe 16.

  In the transport pipe 16, the water in the purified mixed fluid is cooled to change the state from the supercritical state or the high temperature / high pressure vapor state to the liquid state. On the other hand, oxygen and nitrogen in the mixed fluid change the mode from the supercritical state to the gas state. The mixed fluid that has passed through the transport pipe 16 is separated into treated water and gas by the gas-liquid separator 14, and the treated liquid is stored in the treated liquid tank. Gas is also released into the atmosphere.

  The treated water contains almost no suspended solids or organic matter because hardly decomposable organic matter such as phenol that cannot be removed by biological treatment with activated sludge is almost completely oxidized and decomposed. It contains only a small amount of inorganic material that could not be oxidized. Even as it is, it can be reused as industrial water depending on the application. Further, if a filtration process using an ultrafiltration membrane is performed, it can be diverted to an LSI cleaning liquid or the like. The gas separated by the gas-liquid separator 14 is mainly composed of carbon dioxide, nitrogen, and oxygen gas.

  In FIG. 2, a heat exchanger 9 is attached to the outer wall of the transfer pipe 16. The main body of the heat exchanger 9 is composed of an outer tube that covers the outer wall of the transfer tube 16, and a space between the outer tube and the outer wall of the transfer tube 16 is filled with a heat exchange fluid such as water. Then, heat exchange between the outer wall of the transfer pipe 16 and the heat exchange fluid is performed. When the reaction tank 20 is operated, a very high-temperature liquid flows inside the transfer pipe 16, so heat is transferred from the transfer pipe 16 to the heat exchange fluid in the heat exchanger 9, and the heat exchange fluid is heated. The transport direction of the heat exchange fluid in the heat exchanger 9 is opposite to the transport direction of the liquid in the transport pipe 16 so as to perform so-called countercurrent heat exchange. That is, the heat exchange fluid is sent from the outlet valve 13 side to the reaction tank 20 side. This is performed by the heat exchange pump 11 that sends the heat exchange fluid in the heat medium tank 10 to the heat exchanger 9 while sucking the heat exchange fluid. The heat exchange fluid heated through the heat exchanger 9 is sent to a generator through a pipe (not shown). In the generator, power generation is performed by rotating the turbine with an air flow generated when the heat exchange fluid that has been heated to increase the pressure from a liquid to a gas state.

  A part of the heat exchange fluid that has passed through the heat exchanger 9 may be conveyed to the inflow pipe 26 or the raw water tank 1 by a branch pipe and used for preheating the waste water W.

  An exit thermometer (not shown) that detects the temperature of the transport pipe 16 or the temperature of the liquid in the transport pipe 16 is provided near the outlet valve 13 in the transport pipe 16. The programmable sequencer of the control unit controls the drive of the heat exchange pump 11 so that the detection result by the outlet thermometer is below a predetermined upper limit temperature. Specifically, when the detection result by the outlet thermometer reaches a predetermined upper limit temperature, the amount of heat exchange fluid supplied to the heat exchanger 9 is increased by increasing the drive amount of the heat exchange pump 11, The cooling function by the exchanger 9 is enhanced. Accordingly, the liquid is caused to flow into the heat exchanger 9 in a state where the temperature is equal to or lower than the upper limit temperature.

  A heat exchange thermometer (not shown) that detects the temperature of the heat exchange fluid immediately after passing through the heat exchanger 9 is provided in the vicinity of the heat exchanger 9. The temperature of the heat exchange fluid immediately after passing through the heat exchanger 9 is preferably equal to or higher than a predetermined lower limit temperature. Therefore, the programmable sequencer of the control unit controls the driving of the heat exchange pump 11 so that the detection result by the heat exchange thermometer is equal to or lower than a predetermined lower limit temperature. Specifically, when the detection result by the heat exchange thermometer decreases to a predetermined lower limit temperature, the amount of heat exchange fluid supplied to the heat exchanger 9 is decreased by decreasing the drive amount of the heat exchange pump 11. Thereby, the temperature of the heat exchange fluid immediately after passing through the heat exchanger 9 is raised. However, the adjustment of the drive amount of the heat exchange pump 11 based on the detection result by the outlet thermometer is prioritized over the adjustment of the drive amount of the heat exchange pump 11 based on the detection result by the heat exchange thermometer. For this reason, when the detection result by the outlet thermometer is equal to or higher than the predetermined upper limit temperature and the detection result by the heat exchange thermometer is equal to or lower than the predetermined lower limit temperature, the driving amount based on the former detection result The driving amount is increased by prioritizing the adjustment.

  When the organic matter concentration in the wastewater W is relatively high, a large amount of heat is generated by oxidative decomposition of the organic matter. For this reason, although the heater 23 is operated at the initial stage of operation, after the oxidative decomposition of the organic substance is started, the temperature of the mixed fluid of the waste water W and the air A is set to a desired value by the heat generated by the oxidative decomposition of the organic substance. In some cases, the temperature can be naturally increased to the temperature. Therefore, the programmable sequencer of the control unit turns off the heater 23 as the heating means when the detection result by the thermometer 24 that detects the temperature of the outer cylinder 21 becomes higher than a predetermined temperature. Thereby, useless energy consumption can be suppressed.

Next, a characteristic configuration of the fluid purification device according to the embodiment will be described.
In FIG. 4, a plurality of fluid discharge ports 26 a arranged along the longitudinal direction of the inflow pipe 26 are provided at the distal end portion of the inflow pipe 26 inserted into the inner cylinder 22 of the reaction tank 20.

FIG. 5 is a plan sectional view showing the inflow pipe 26. At the tip of the inflow pipe 26, at positions (P ₁ , P ₂ , P ₃ , P ₄ , P ₅ , P ₆ , P ₇ ) where a plurality of fluid discharge ports 26 a are provided in the longitudinal direction of the inflow pipe 26. , Respectively, are provided with a pair of discharge ports composed of two fluid discharge ports 26 a facing each other in the cross-sectional direction of the inflow pipe 26.

  FIG. 6 is a plan sectional view showing the inner cylinder 22 together with the inflow pipe 26. The figure shows an example in which the waste water W is heated and pressurized to 374.2 ° C. or higher and 21.8 MPa or higher in the inner cylinder 22 to change from the liquid state to the supercritical state. The air A is pressurized to 21.8 MPa or more, which is the same pressure as that in the inner cylinder 22, when it passes through an oxidant inlet valve (not shown) (8 in FIG. 2) outside the reaction tank. The critical temperature of air A is below freezing point (−140.7 ° C.), and the critical pressure is 3.72 MPa. Since the temperature of the air A being pumped in a high pressure state by the oxidant pump (6 in FIG. 2) exceeds 0 [° C.] and exceeds the critical pressure, the air A is an oxidant inlet valve (not shown). When it passes through, it becomes supercritical. Then, it enters the inner cylinder 22 in a supercritical state.

On the other hand, when the waste water W passes through a raw water inlet valve (not shown) (5 in FIG. 2) outside the reaction tank, it is 21.8 MPa or more which is the same pressure as that in the inner cylinder 22 (equal or more than the critical pressure of water). Pressure). The critical temperature of water is very high (374.2 ° C.), and the waste water W that has not reached the critical temperature at this point is still in a liquid state. Although the waste water W in the inflow pipe 26 is pressurized to a pressure equal to or higher than the critical pressure, it is conveyed to the tip of the inflow pipe 26 in a liquid state. Then, at position P ₁ , position P ₂ , position P ₃ , position P ₄ , position P ₅ , position P ₆ , position P ₇ (refer to FIG. 5 for the position), the fluid discharge port 26a is directed to the outside of the pipe. Protruding. As shown in the figure, the protruding portion (hereinafter referred to as “the protruding portion of the waste water W discharge port”) has a spherical shape due to surface tension.

In the inner cylinder 22, the supercritical air A moves from the rear end side of the inflow pipe 26 toward the front end side (from the front end side to the rear end side of the inner cylinder). As already described, the air A is preheated in the inter-cylinder space between the outer cylinder (21) and the inner cylinder (22), so the temperature is raised to a temperature equal to or higher than the critical temperature of water. ing. A spherical “exhaust port protruding portion of the waste water W” protruding from the fluid discharge port 26a of the inflow pipe 26 is heated to a temperature higher than the critical temperature by touching the air A, and as shown by an arrow S in FIG. Change from state to supercritical state. At this time, the volume is greatly increased as compared with the liquid state, and the air A in the supercritical state is positively mixed. Since water in a supercritical state has a very high ability to dissolve substances, organic substances and inorganic substances contained in the waste water W are quickly dissolved in water in the supercritical state. Then, while being in contact with the air A, it is rapidly oxidized and decomposed. Such a phenomenon occurs in the vicinity of position P ₁ , position P ₂ , position P ₃ , position P ₄ , position P ₅ , position P ₆ , and position P ₇ .

  In such a configuration, the position where the rapid oxidative decomposition of the organic substance is dispersed in a plurality in the longitudinal direction of the inner cylinder 22, so that the organic substance is rapidly oxidatively decomposed at only one position in the longitudinal direction. Thus, local heat generation of the inner cylinder 22 can be suppressed, and fatigue due to thermal expansion and contraction of the inner cylinder 22 and the outer cylinder (21) can be suppressed.

As shown in FIG. 5, at the distal end portion of the inflow pipe 26, the position P ₁ , the position P ₂ , the position P ₃ , the position P ₄ , the position P ₅ , the position P ₆ , and the position P ₇ in the longitudinal direction respectively. A pair of discharge ports including two fluid discharge ports 26a facing each other in the tube cross-sectional direction is provided. In such a configuration, at least two fluid discharge ports 26 a are provided in the circumferential direction of the inner cylinder 22, and the positions where the rapid oxidative decomposition of the organic matter is dispersed in at least two, so that the inner direction can be Local heat generation of the cylinder 22 and the outer cylinder 21 can be suppressed.

  Moreover, in the fluid purification apparatus which concerns on embodiment, the front-end | tip of the inflow tube 26 is block | closed like illustration. In such a configuration, the waste water W can be reliably discharged from each of the plurality of fluid discharge ports 26a provided along the longitudinal direction with respect to the outer peripheral surface of the inflow pipe 26 by not projecting the waste water W from the pipe tip.

  In addition, although the example which makes waste water W the supercritical state in the inner cylinder 22 was demonstrated, you may make it the above-mentioned high temperature high pressure state (it is less than the critical pressure of water). In this case, the “extruding portion of the waste water W discharge port” is brought into a high-temperature and high-pressure steam state by touching the air A, and the organic matter is dispersed in the air A while increasing the volume in the vicinity of the fluid discharge port 26a. . The organic matter dispersed in the air A is rapidly oxidatively decomposed under high temperature and high pressure conditions.

  In FIG. 6, a plurality of tubular catalysts 25 are arranged in the radial direction of the inner cylinder 22 in a region downstream of the fluid conveyance direction in the entire area in the longitudinal direction of the inner cylinder 22. The catalyst 25 is made of a material that promotes oxidative decomposition of organic substances and ammonia nitrogen contained in the waste water W. Examples of such materials include Ru, Pd, Rh, Pt, Au, Ir, Os, Fe, Cu, Zn, Ni, Co, Ce, Ti, or Mn. Moreover, the compound containing at least any one among them may be sufficient. Most of the organic matter contained in the waste water W is oxidatively decomposed in the first half region in the longitudinal direction of the inner cylinder 22, but organic matter and ammonia nitrogen that are not oxidatively decomposed even after passing through the first half region are separated by this catalyst 25. Oxidative decomposition is promoted. In such a configuration, even if a hardly decomposable organic substance is contained in the waste water W, it can be completely oxidatively decomposed. Even if ammonia nitrogen is contained in a large amount in the waste water W, it can be completely oxidatively decomposed.

  When the organic matter concentration of the waste water W is very high, the amount of heat generated by the oxidative decomposition of the organic matter contained in the waste water W in the inner cylinder 22 causes the waste water W and air A newly flowing into the inner cylinder 22 to flow. It may exceed the amount of heat required to raise the temperature to the desired temperature. In this case, the temperature of the mixed fluid in the inner cylinder 22, the outer cylinder 21, and the inner cylinder 22 continues to rise as it is. Therefore, the programmable sequencer of the control unit feeds the raw water W into the inner cylinder 22 by the raw water supply pump (3) when the detection result by the thermometer (24) becomes higher than a predetermined upper limit temperature. Reduce the speed or temporarily stop driving the raw water supply pump. At this time, the oxidant pump 6 also decreases the driving speed or temporarily stops driving. Thereby, the excessive temperature rise of the inner cylinder 22 or the outer cylinder 21 can be prevented.

  In addition, although the example which arrange | positioned the thermometer (24) so that the temperature of the outer peripheral surface of the outer cylinder 21 was detected was demonstrated, the temperature of the air A in the space between cylinders, the temperature of the outer peripheral surface of the inner cylinder 22, or A thermometer (24) may be disposed so as to detect the temperature of the mixed fluid in the inner cylinder 22.

  Moreover, although the example which has arrange | positioned the reaction tank (20) with the horizontal attitude | position which follows the longitudinal direction of a pipe | tube along a horizontal direction was demonstrated, the vertical attitude | position which follows the longitudinal direction of a pipe | tube along a perpendicular direction, You may arrange | position the reaction tank (20) with the inclination-type attitude | position which makes a direction follow the inclination direction inclined from the perpendicular direction or the horizontal direction.

  FIG. 7 is a longitudinal sectional view showing the inner cylinder 22 and the inflow pipe 26 in the vertical reaction tank. The air A introduced into the inter-cylinder space between the outer cylinder (not shown) and the inner cylinder 22 moves in the inter-cylinder space from the lower side in the vertical direction to the upper side. Then, after entering the inside of the inner cylinder 22 from the tip opening at the upper end of the inner cylinder 22, as indicated by an arrow in the figure, it moves from the upper side to the lower side in the vertical direction.

  The inflow pipe 26 is disposed in such a posture that its tip is directed downward in the vertical direction. And the some fluid discharge port provided in the front-end | tip part of the inflow tube 26 is located in a line toward the downward direction from the upper direction of the perpendicular direction. The air A moving in the inner cylinder 22 from the upper side to the lower side in the vertical direction protrudes in a spherical shape from the fluid discharge port when passing through the position facing the individual fluid discharge ports. The “part” is contacted to change it from a liquid state to a supercritical state or a high temperature and high pressure vapor state. And it mixes with the organic matter in the wastewater W, and contributes to the oxidative decomposition of the organic matter.

What has been described above is merely an example, and the present invention has a specific effect for each of the following modes.
[Aspect A]
While having a double structure in which a cylindrical inner cylinder (for example, inner cylinder 22) is disposed inside a cylindrical outer cylinder (for example, outer cylinder 21), the purification target fluid (for example, waste water W) In order to flow into the inside of the cylinder, an inflow pipe (for example, the inflow pipe 26) in which its tip is inserted along the longitudinal direction with respect to the inner cylinder, and an oxidizing agent (for example, air A) are provided. Of the oxidizer inlet provided in the outer cylinder for introduction into the inter-cylinder space between the outer cylinder and the inner cylinder, and the inflow pipe among the entire longitudinal area of the inner cylinder An opening provided in a region on the rear end side of the front end of the inner cylinder, and after the oxidant introduced into the inter-cylinder space is caused to flow into the inner cylinder from the opening, the inner cylinder Organic matter in the fluid to be purified while mixing with the fluid to be purified inside the body and heating and pressurizing the obtained mixed fluid In a fluid purification device including a reaction tank (for example, the reaction tank 20) that purifies a target fluid to be purified by oxidative decomposition, a plurality of fluid discharge ports (for example, the fluid discharge ports 26a) arranged along the longitudinal direction of the inflow pipe are arranged as described above. It is provided in the said front-end | tip part of an inflow tube.

[Aspect B]
Aspect B is a discharge port comprising two fluid discharge ports facing each other in the cross-sectional direction of the inflow pipe at a position where a plurality of the fluid discharge ports are provided in the longitudinal direction of the inflow pipe, respectively. A pair is provided. In such a configuration, as already described, in the circumferential direction of the inner cylindrical body, at least two fluid discharge ports are provided, and at least two positions that cause rapid oxidative decomposition of organic matter are dispersed in the circumferential direction. In addition, local heat generation of the inner cylinder and the outer cylinder can be suppressed.

[Aspect C]
Aspect C is characterized in that in Aspect B, the tip of the inflow pipe is closed. In such a configuration, as already described, the purification target fluid is not projected from the tip of the inflow pipe, so that the purification target fluid is respectively supplied from a plurality of fluid discharge ports provided along the longitudinal direction with respect to the peripheral surface of the inflow pipe. It can be discharged reliably.

[Aspect D]
Aspect D is any one of aspects A to C, wherein the fluid to be purified before purification is pumped toward the distal end of the inflow pipe (for example, raw water supply pump 3), and the inner cylinder Temperature detection means (for example, a thermometer 24) for detecting the temperature of the mixed fluid, the temperature of the inner cylinder, or the temperature of the outer cylinder, and the pre-purification fluid pumping based on the detection result by the temperature detection means The control means (for example, programmable sequencer) which controls the drive of a means is provided, It is characterized by the above-mentioned. In such a configuration, as already described, it is possible to avoid an excessive increase in the temperature of the inner cylinder 22 and the outer cylinder 21 due to the fact that the organic matter is contained in the waste water W at a very high concentration.

[Aspect E]
Aspect E provides an oxidant pumping means (for example, an oxidant pump 6) for pumping the oxidant toward the oxidant inlet in aspect D, and based on the detection result by the temperature detector, The control means is configured to perform a process for controlling the driving of the oxidant pumping means. In such a configuration, as described above, when the drive speed of the pre-purification fluid pumping means is low, or when the drive of the pre-purification fluid pumping means is temporarily stopped, the oxidant pumping means is operated as usual. Therefore, it is possible to avoid unnecessary consumption of the oxidant due to the driving.

[Aspect F]
Aspect F uses Ti, Ta, Au, Pt, Ir, Rh or Pd, or an alloy containing at least one of them as the inner cylinder in any one of aspects A to E. It is characterized by. With such a configuration, desired corrosion resistance can be exerted on the inner cylinder.

[Aspect G]
Aspect G is characterized in that in any of Aspects A to F, the outer cylinder is made of stainless steel, nickel, or an alloy containing at least stainless steel or nickel. In such a configuration, the outer cylinder can exhibit pressure resistance that can withstand a desired high-pressure condition.

[Aspect H]
Aspect H is a fluid purification apparatus according to any one of the aspects A to G, wherein a catalyst that promotes oxidative decomposition of organic matter or ammonia nitrogen is disposed in the inner cylinder. In such a configuration, even when a hardly decomposable organic substance is contained in the purification target fluid, it can be satisfactorily oxidatively decomposed. Moreover, even if ammonia nitrogen is contained in a large amount in the fluid to be purified, it can be oxidized and decomposed satisfactorily.

[Aspect I]
Aspect I is that in aspect H, the catalyst is Ru, Pd, Rh, Pt, Au, Ir, Os, Fe, Cu, Zn, Ni, Co, Ce, Ti, and Mn. It is characterized by using the thing which consists of a compound containing. In such a configuration, the catalyst can exhibit the oxidative decomposition catalytic performance of organic matter and ammonia nitrogen.

[Aspect J]
Aspect J is characterized in that in any one of Aspects A to I, oxygen gas, ozone gas, air, or hydrogen peroxide water is used as the oxidizing agent. In such a configuration, the oxidizing agent can be supplied to the reaction vessel in a fluid state.

3: Raw water supply pump (fluid pre-purification means)
6: Oxidant pump (oxidant pump)
20: Reaction tank 21: Outer cylinder (outer cylinder)
22: Inner cylinder (inner cylinder)
23: Heater (heating means)
24: Thermometer (temperature detection means)
25: Catalyst 26: Inflow pipe 26a: Fluid discharge port W: Waste water (fluid to be purified)
A: Air (oxidizer)

JP 2001-170334 A

Claims (10)

In addition to having a double structure in which a cylindrical inner cylinder is disposed inside a cylindrical outer cylinder, in order to allow the fluid to be purified to flow into the inner cylinder, An inflow pipe inserted along the longitudinal direction of the cylinder and an oxidizer provided in the outer cylinder for introducing an oxidant into the inter-cylinder space between the outer cylinder and the inner cylinder. And an opening provided in a region on the rear end side with respect to the front end of the inflow pipe in the longitudinal direction of the inner cylindrical body, and introduced into the inter-cylinder space. After the oxidant is caused to flow into the inner cylinder through the opening, the oxidant is mixed with the purification target fluid inside the inner cylinder, and the obtained mixed fluid is heated and pressurized while being mixed in the purification target fluid. In a fluid purification apparatus comprising a reaction tank that decomposes organic matter by an oxidation reaction to purify a fluid to be purified,
A fluid purification apparatus comprising a plurality of fluid discharge ports arranged along the longitudinal direction of the inflow pipe at the tip end portion of the inflow pipe. The fluid purification device according to claim 1,
A discharge port pair comprising two fluid discharge ports facing each other in the cross-sectional direction of the inflow tube is provided at a position where a plurality of the fluid discharge ports are respectively provided in the longitudinal direction of the inflow tube. Fluid purifier. The fluid purification apparatus according to claim 2, wherein
A fluid purification device, wherein a tip of the inflow pipe is closed. The fluid purification device according to any one of claims 1 to 3,
A pre-purification fluid pumping means for pumping the purification target fluid before purification toward the tip of the inflow pipe;
Temperature detecting means for detecting the temperature of the mixed fluid in the inner cylinder, the temperature of the inner cylinder, or the temperature of the outer cylinder;
A fluid purification device comprising: control means for controlling driving of the pre-purification fluid pumping means based on a detection result by the temperature detection means. The fluid purification device according to claim 4, wherein
While providing an oxidizer pumping means for pumping the oxidizer toward the oxidizer inlet,
The fluid purification apparatus according to claim 1, wherein the control means is configured to perform a process of controlling the driving of the oxidant pumping means based on a detection result by the temperature detecting means. The fluid purification device according to any one of claims 1 to 5,
A fluid purification device using Ti, Ta, Au, Pt, Ir, Rh or Pd, or an alloy containing at least one of them as the inner cylinder. The fluid purification device according to any one of claims 1 to 6,
A fluid purification device using stainless steel, nickel, or an alloy containing at least stainless steel or nickel as the outer cylinder. The fluid purification device according to any one of claims 1 to 7,
A fluid purification device, wherein a catalyst that promotes oxidative decomposition of organic matter or ammonia nitrogen is disposed in the inner cylinder. The fluid purification apparatus according to claim 8, wherein
As the catalyst, a catalyst comprising a compound containing at least one element of Ru, Pd, Rh, Pt, Au, Ir, Os, Fe, Cu, Zn, Ni, Co, Ce, Ti, and Mn is used. A fluid purification device characterized by that. The fluid purification device according to any one of claims 1 to 9,
A fluid purification apparatus using oxygen gas, ozone gas, air, or hydrogen peroxide as the oxidant.

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