Neutralization treatment system of ammonia-containing waste water and neutralization treatment method of ammonia-containing waste water

Abstract

To provide a neutralization treatment system of an ammonia-containing waste water capable of efficient neutralization of waste water containing ammonia.SOLUTION: A neutralization treatment system 100 of ammonia-containing waste water neutralizes waste water WF containing ammonia AM. The neutralization treatment system 100 of ammonia-containing waste water includes one or a plurality of sludge oil tank 700, a sludge discharge line 160 to supply waste water WF to the sludge oil tank 700, a neutralizer supply line 170 to supply a neutralizer N to the sludge oil tank 700, and a sensor 720 to measure pH of waste water WF or ammonia concentration of waste water WF.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a system for neutralizing an ammonia-containing waste liquid and a method for neutralizing an ammonia-containing waste liquid. [Background technology]

[0002] As a countermeasure against global warming, ammonia fuel, which does not emit carbon dioxide, a greenhouse gas, when burned, has attracted attention as a promising energy source for realizing a carbon-neutral society. In recent years, the practical application of ammonia-fired gas turbines and ammonia-fired engines that use liquid ammonia as fuel has been progressing. Development is also underway to operate ammonia-fueled ships that use liquid ammonia as fuel, so-called zero-emission ships.

[0003] However, when liquid ammonia is used as fuel for ships and other vessels, unburned ammonia gas from the engine dissolves in the water in the lubricating oil. This water is mixed into the lubricating oil due to humidity during operation or condensation after the engine is stopped. If the engine is operated without removing the water, the ammonia concentration in the engine increases, and the ammonia dissolves in the water in the lubricating oil. Materials exposed to ammonia water or an ammonia atmosphere are prone to corrosion, which is a problem. For this reason, lubricating oil containing ammonia is disposed of as waste liquid.

[0004] Such waste liquid containing ammonia is collected in a collection tank or neutralized (see, for example, Patent Documents 1 and 2). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 6934555 [Patent Document 2] Patent No. 3863610 Summary of the Invention [Problem to be solved by the invention]

[0006] Since the installation space for recovery tanks and the like is limited on ships and at onshore power plants, it is desirable to be able to neutralize waste liquid containing ammonia more efficiently.

[0007] Therefore, an object of the present invention is to provide a system for neutralizing ammonia-containing waste liquid and a method for neutralizing ammonia-containing waste liquid, which can solve the above-mentioned problems and efficiently neutralize ammonia-containing waste liquid. [Means for solving the problem]

[0008] In order to solve the above problems, the present invention provides a system for neutralizing ammonia-containing waste liquid, which neutralizes waste liquid containing ammonia, and includes one or more waste liquid tanks or sludge tanks, a sludge discharge line that supplies the waste liquid to the waste liquid tank or sludge tank, a neutralizing agent supply line that supplies a neutralizing agent to the waste liquid tank or sludge tank, and a sensor that measures the pH of the waste liquid or the ammonia concentration of the waste liquid.

[0009] Furthermore, the neutralization treatment system for ammonia-containing waste liquid of the present invention includes a sludge discharge line for discharging sludge, one or more waste liquid tanks provided at the end of the sludge discharge line, a sludge tank for storing waste liquid from the waste liquid tank, a waste liquid discharge line for supplying the waste liquid to the sludge tank, a neutralizing agent supply line for supplying a neutralizing agent to the waste liquid tank, and a sensor for measuring the pH of the waste liquid in the waste liquid tank or the ammonia concentration of the waste liquid.

[0010] The present invention also provides a method for neutralizing an ammonia-containing waste liquid, which comprises measuring the pH or ammonia concentration of the waste liquid with a sensor, and adding a neutralizing agent to the waste liquid according to either or both of the measured pH value and the measured ammonia concentration value of the waste liquid measured by the sensor, to neutralize the waste liquid. [Effects of the Invention]

[0011] The system for neutralizing ammonia-containing waste liquid and the method for neutralizing ammonia-containing waste liquid of the present invention can efficiently neutralize waste liquid containing ammonia. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a block diagram showing a system for neutralizing ammonia-containing waste liquid and a method for neutralizing ammonia-containing waste liquid according to a first embodiment of the present invention. [Figure 2] FIG. 1 is a block diagram showing a modified example of the system for neutralizing ammonia-containing waste liquid and the method for neutralizing ammonia-containing waste liquid according to the first embodiment of the present invention. [Figure 3] FIG. 1 is a block diagram showing a modified example of the system for neutralizing ammonia-containing waste liquid and the method for neutralizing ammonia-containing waste liquid according to the first embodiment of the present invention. [Figure 4] FIG. 10 is a block diagram showing a system for neutralizing ammonia-containing waste liquid and a method for neutralizing ammonia-containing waste liquid according to a second embodiment of the present invention. [Figure 5] FIG. 10 is a diagram showing a system for neutralizing ammonia-containing waste liquid and a method for neutralizing ammonia-containing waste liquid according to a third embodiment of the present invention, and is a schematic diagram showing a waste liquid tank for storing waste liquid. [Figure 6] FIG. 10 is a diagram showing a system for neutralizing ammonia-containing waste liquid and a method for neutralizing ammonia-containing waste liquid according to a fourth embodiment of the present invention, and is a schematic diagram showing a waste liquid tank for storing waste liquid. DETAILED DESCRIPTION OF THE INVENTION

[0013] [First embodiment] A system 100 for neutralizing ammonia-containing waste liquid and a method for neutralizing ammonia-containing waste liquid according to a first embodiment of the present invention will be described in detail with reference to FIG.

[0014] <Neutralization treatment system for ammonia-containing wastewater> The ammonia-containing waste liquid neutralization treatment system (hereinafter referred to as "neutralization treatment system" as appropriate) 100 shown in FIG. 1 is an apparatus for purifying and neutralizing waste fluid (hereinafter referred to as "waste fluid WF") such as lubricating oil LO, fuel oil, bilge water, etc., which contains ammonia (hereinafter referred to as "ammonia AM") used in an engine 200 such as a combustion engine installed on a ship or in a limited installation space on land (for example, a remote island power plant or an existing power plant).

[0015] An example of the neutralization treatment system 100 according to the present invention will be described below, taking as an example a case where the waste liquid WF is lubricating oil LO used in an engine 200 that burns liquid ammonia. The neutralization treatment system 100 according to the present invention can be used for all ammonia waste liquid as long as the waste liquid WF contains ammonia AM, and an example of the neutralization treatment system 100 according to the present invention will be described below, taking as an example a system equipped with a purifier 1. In an engine 200 that uses liquid ammonia as fuel, the lubricating oil LO inside the engine 200 may be contaminated with sludge SG and aqueous ammonia AW.

[0016] The neutralization treatment system 100 includes a purifier 1. The purifier 1 is a three-phase separation type separator plate centrifuge that separates a lubricating oil (LO) stock solution DO mixed with ammonia water (hereinafter referred to as "ammonia water AW") into a light liquid (purified lubricating oil LO), a heavy liquid (ammonia water AW containing ammonia AM), and a solid sludge (hereinafter referred to as "sludge SG"). The neutralization treatment system 100 mainly includes a lubricating oil tank 300, a lubricating oil supply pump P1, the purifier 1, a waste liquid tank 500, a neutralization tank 600, a sludge tank 700, a heavy liquid discharge line 120, a neutralizing agent supply line 170, a waste liquid discharge line 180, a sensor 720 (a pH meter 721, an ammonia sensor 722, and a liquid level meter 730), a stock liquid supply line 130, and a sludge discharge line 160. The neutralization treatment system 100 is located on board a ship.

[0017] ≪Institution≫ For example, engine 200 shown in FIG. 1 is a marine diesel engine installed on a ship, which uses liquid ammonia as fuel, which has zero emissions of carbon dioxide, a greenhouse gas, and may be a turbine engine. Engine 200 is composed of a mechanism in which a crankshaft and a piston are connected only by a connecting rod. In engine 200, side pressure, which is a lateral force, is generated on the piston, causing uneven wear in the cylinder. For this reason, engine 200 uses lubricating oil LO to improve piston movement. Engine 200 may also be one that burns a mixture of liquid ammonia and a fossil fuel such as natural gas.

[0018] <Lubricant discharge line> 1 is a piping line for sending lubricating oil LO (undiluted liquid DO) used in the engine 200 to the lubricating oil tank 300. One end of the lubricating oil discharge line 150 is connected to the engine 200, and the other end is connected to the lubricating oil tank 300.

[0019] <Lubricating oil tank and lubricating oil> 1, the lubricating oil tank 300 is a tank for storing the stock solution DO containing the lubricating oil LO used by the engine 200. The stock solution DO supplied from the engine 200 to the lubricating oil tank 300 contains ammonia AM derived from the ammonia fuel. For this reason, the lubricating oil tank 300 is a tank with a lid that prevents the vaporized ammonia AM from leaking out of the lubricating oil tank 300. Furthermore, the undiluted liquid DO contains water that has been mixed in the engine 200 .

[0020] <Ammonia water and water> Ammonia water AW is an alkaline aqueous solution in which ammonia AM is dissolved in water. Ammonia water AW has a distinctive pungent odor. Ammonia water AW may corrode the fluororubber O-rings and copper alloy heavy liquid and light liquid impellers used in the purifier 1. For this reason, it is preferable that these parts are made of corrosion-resistant materials.

[0021] <Undiluted solution supply line> 1 is a piping line for supplying the raw liquid DO (lubricating oil LO mixed with sludge SG and ammonia water AW) stored in the lubricating oil tank 300 to the purifier 1. The raw liquid supply line 130 is made up of a heater upstream line 131 from the lubricating oil tank 300 to the heater 400, and a heater downstream line 132 from the heater 400 to the purifier 1. A lubricating oil supply pump P1 is provided in the heater upstream line 131, and a three-way valve 134 is provided in the heater downstream line 132.

[0022] <Lubricating oil supply pump> The lubricating oil supply pump P1 is a pump for sending the stock solution DO in the lubricating oil tank 300 from the stock solution supply line 130 to the purifier 1 via the heater 400. As shown in FIG. 1, the stock solution DO in the heater upstream line 131 is mixed with ammonia water AW.

[0023] <Heater> The heater 400 is an oil heater that heats the lubricating oil LO to be sent to the purifier 1. The heater 400 heats the lubricating oil LO to reduce its viscosity, thereby increasing the efficiency of separation of solids and / or water in the purifier 1. As shown in Fig. 1, the raw solution DO in the heater downstream line 132 is mixed with ammonia water AW and sludge SG.

[0024] <Light liquid discharge line> The light liquid discharge line 140 is a flow path for returning the lubricating oil LO (light liquid) purified by the purifier 1 to the lubricating oil tank 300. The light liquid discharge line 140 is made up of a piping path extending from the discharge port of the purifier 1 to the lubricating oil supply port of the lubricating oil tank 300.

[0025] <Purifier> The purifier 1 is a device for separating / removing sludge SG (solids) and ammonia water AW contained in the raw liquid DO supplied from the lubricating oil tank 300 from the lubricating oil LO. The purifier 1 may be, for example, a plate-type centrifuge that separates the raw liquid DO into three phases: liquid (light liquid), liquid (heavy liquid), and solids, by the centrifugal force of a rotor rotating at high speed.

[0026] <Sludge discharge line> The sludge discharge line 160 is a discharge path for discharging the sludge SG that has been centrifuged in the purifier 1 to the outside of the purifier 1. The upstream side of the sludge discharge line 160 is connected to the sludge discharge port of the purifier 1, and the downstream side is connected to a sludge tank 700 via a waste liquid discharge line 180 (see FIG. 1). The sludge SG in the purifier 1 is released into the waste liquid discharge line 180, stored in the sludge tank 700, and then disposed of.

[0027] <Waste liquid discharge line> The waste liquid discharge line 180 is a waste liquid discharge means for supplying the waste liquid WF to the sludge tank 700 .

[0028] <Waste liquid tank> 1 is a tank for storing waste liquid WF containing sludge SG separated by the purifier 1. The waste liquid tank 500 is disposed downstream of the sludge discharge line 160. There may be one or more waste liquid tanks 500. The sludge SG is deposited on the outermost diameter side of the rotor 3 by the centrifugal force of the purifier 1 and is discharged from the sludge discharge port to the sludge discharge line 160. In the first embodiment, the ammonia water AW (heavy liquid) separated in the purifier 1 is also stored in the waste liquid tank 500. The waste liquid tank 500 may be provided with an input water supply line 712 and a vent line 770, similar to the sludge tank 700.

[0029] <Neutralization tank, neutralizing agent supply line and waste liquid> The neutralization tank 600 is a tank for storing a neutralizer (hereinafter referred to as "neutralizer N") that neutralizes the mixture of sludge SG and ammonia water AW (hereinafter referred to as "waste liquid WF") stored in the waste liquid tank 500. The neutralization tank 600 is provided with a neutralizer supply line 170 that supplies the neutralizer N in the neutralization tank 600 to the waste liquid tank 500. The neutralizing agent supply line 170 is a neutralizing agent supply means for supplying the neutralizing agent N to the waste liquid tank 500 .

[0030] <Neutralizer> The neutralizing agent N is used to neutralize the waste liquid WF containing ammonia water AW in the waste liquid tank 500, and is composed of, for example, a substance having an acidic component such as citric acid. The neutralizing agent N may be a solid (powder (including crystalline state)) or a liquid, as long as it neutralizes the waste liquid WF containing ammonia water AW. The neutralizing agent N is introduced into the waste liquid WF in the sludge tank 700 from the neutralizing agent supply line 170. The neutralizing agent N is supplied according to the measured pH value and ammonia concentration value of the waste liquid WF detected by the sensor 720, and neutralizes the waste liquid WF. The neutralizing agent N is preferably citric acid. Citric acid is easy to handle and highly safe. The neutralizing agent N may be citric acid powder (crystals of anhydrous citric acid (C6H8O7) or citric acid hydrate (C6H8O7·H2O)) or an aqueous citric acid solution. When citric acid is used as the neutralizing agent N, iron oxide may be added to the waste liquid WF as a detoxifying agent. When citric acid and iron oxide are added to ammonia water AW, ammonium iron citrate is produced. Neutralizing agent N and the detoxifying agent can be solid or liquid.

[0031] <Sludge tank> The sludge tank 700 is a tank for storing the waste liquid WF discharged from the waste liquid tank 500. The sludge tank 700 is provided with the waste liquid discharge line 180. If the neutralized waste liquid WF in the sludge tank 700 is at 40°C or higher, a cooling device for cooling the waste liquid WF may be installed. The sludge tank 700 storing the neutralized waste liquid WF in which the ammonia AM has been neutralized and made harmless can be easily carried out and moved from the installation site.

[0032] <Input water supply line> The input water supply line 712 is a flow path for supplying an appropriate amount of water to the sludge tank 700 or the waste liquid tank 500 in accordance with the components, concentration, etc. of the waste liquid WF in the sludge tank 700 or the waste liquid tank 500. The input water supply line 712 may be provided as needed, or may be omitted.

[0033] <Vent line> Vent line 770 is a pipe for discharging gas and water vapor in the gas phase of sludge tank 700 or waste liquid tank 500. Vent line 770 serves to adjust the expansion and contraction of gas caused by changes in the pressure and temperature of the gas inside sludge tank 700, and to remove unnecessary gas. This vent line 770 may be equipped with a valve, a pump, a filter, etc.

[0034] <Sensor> The sensor 720 shown in FIG. 1 or 4 is a detector including a pH meter 721 that measures the pH of the waste liquid WF in the sludge tank 700 or waste liquid tank 500, an ammonia sensor 722 that measures the ammonia concentration of the waste liquid WF, and the like. The pH meter 721 measures the pH of the waste liquid WF in the sludge tank 700 or the waste liquid tank 500, and by adding an optimal amount of neutralizing agent N to the waste liquid WF based on the measured value, the waste liquid WF can be efficiently neutralized. The ammonia sensor 722 measures the ammonia concentration of the waste liquid WF in the sludge tank 700 or the waste liquid tank 500, and by adding an optimal amount of neutralizing agent N to the waste liquid WF based on the measured value, the waste liquid WF can be efficiently neutralized.

[0035] <Heavy liquid discharge line> The heavy liquid discharge line 120 is a flow path for discharging the ammonia water AW (separated water) centrifuged in the purifier 1. The ammonia water AW in the purifier 1 is stored in a sludge tank 700 and then discarded.

[0036] ≪Effect≫ Next, the operation of the system 100 for neutralizing ammonia-containing waste liquid and the method for neutralizing ammonia-containing waste liquid according to the first embodiment of the present invention will be described with reference to FIG.

[0037] As shown in FIG. 1, lubricating oil LO (undiluted oil DO) used in an engine 200 is stored in a lubricating oil tank 300 and then introduced into the purifier 1 through an undiluted oil supply line .

[0038] The ammonia water AW and sludge SG (waste liquid WF) separated in the purifier 1 shown in FIG. 1 are discharged from a sludge discharge line 160 to a waste liquid tank 500, and then sent from a waste liquid discharge line 180 to a sludge tank 700 where they are stored.

[0039] On ships, sludge SG must be landed and treated as industrial waste. However, if the ammonia concentration of the sludge SG is high, landing may be refused. For this reason, it is preferable to neutralize waste liquid WF containing ammonia AM on board the ship.

[0040] In the waste liquid tank 500, as shown in FIG. 1, at least one of the pH and the ammonia concentration of the waste liquid WF stored in the waste liquid tank 500 is measured by a sensor 720 (a pH meter 721, an ammonia sensor 722) (measurement step). Then, the waste liquid WF is neutralized by adding a neutralizing agent N to the waste liquid WF according to at least one of the measured pH value of the waste liquid WF measured by the sensor 720 and the measured ammonia concentration of the waste liquid WF (neutralization step). In this way, the waste liquid WF containing ammonia AM can be efficiently neutralized.

[0041] 1, the neutralization treatment system 100 according to the first embodiment neutralizes waste liquid WF containing ammonia AM. The neutralization treatment system 100 includes one or more waste liquid tanks 500, a sludge discharge line 160 that supplies waste liquid WF to the waste liquid tank 500, a neutralizing agent supply line 170 that supplies neutralizing agent N to the waste liquid tank 500, and a sensor 720 (a pH meter 721, an ammonia sensor 722) that measures the pH of the waste liquid WF or the ammonia concentration of the waste liquid WF.

[0042] According to this configuration, the neutralizing agent N can be supplied to the waste liquid WF according to at least one of the measured pH value of the waste liquid WF detected by the sensor 720 and the measured ammonia concentration value of the waste liquid WF, thereby enabling efficient neutralization.

[0043] The process of supplying the neutralizing agent N to the waste liquid WF in accordance with the measured value of the ammonia concentration of the waste liquid WF may be performed by automatically operating a pump or valve using a control device, or may be performed manually.

[0044] Furthermore, the neutralizing agent N has an acidic component. If the neutralizing agent N is acidic, it can neutralize the waste liquid WF containing ammonia AM.

[0045] Also, the sensor 720 shown in FIG. 1 is either a pH meter 721 or an ammonia sensor 722, or both. In this configuration, the pH value and ammonia concentration can be measured directly, so that an appropriate amount of neutralizing agent N can be supplied to the waste liquid WF.

[0046] In addition, it is preferable that the neutralizer N contains citric acid. According to this configuration, citric acid is easy to handle and highly safe, making it easy to transport and store.

[0047] As shown in FIG. 1, the waste liquid tank 500 is provided with an input water supply line 712 for supplying water to the waste liquid tank 500 . According to this configuration, the waste liquid tank 500 is provided with the input water supply line 712, and by supplying water from the input water supply line 712, the waste liquid WF in the waste liquid tank 500 can be appropriately cooled and diluted.

[0048] The neutralization treatment system 100 includes one or more waste liquid tanks 500 for storing the waste liquid WF. According to this configuration, the neutralization treatment system 100A is provided with one or more waste liquid tanks 500, and thus can store waste liquid WF generated on board a ship or the like as needed depending on the amount of waste liquid WF.

[0049] 1, the method for neutralizing ammonia-containing waste liquid of this embodiment neutralizes waste liquid WF containing ammonia AM. Specifically, the pH or ammonia concentration of the waste liquid WF stored in the sludge tank 700 or the waste liquid tank 500 is measured by a sensor 720 (a pH meter 721, an ammonia sensor 722, etc.), and the waste liquid WF is neutralized by adding a neutralizing agent N to the waste liquid WF according to either or both of the measured pH value and the measured ammonia concentration value of the waste liquid WF measured by the sensor 720.

[0050] According to this method for neutralizing ammonia-containing wastewater, the wastewater WF can be efficiently neutralized by adding a neutralizing agent N to the wastewater WF according to the measured pH value or the measured ammonia concentration value of the wastewater WF measured by the sensor 720.

[0051] [Modification of the first embodiment] The present invention is not limited to the first embodiment described above, and various modifications and changes are possible within the scope of its technical concept, and it goes without saying that the present invention also covers such modified and changed inventions.

[0052] In the following, modifications of the system 100 for neutralizing treatment of ammonia-containing waste liquid and the method for neutralizing treatment of ammonia-containing waste liquid according to the first embodiment will be described, focusing on the differences from the system 100 for neutralizing treatment of ammonia-containing waste liquid and the method for neutralizing treatment of ammonia-containing waste liquid according to the first embodiment. Note that the same reference numerals will be used to designate components that have already been described, and descriptions thereof will be omitted. 2 and 3 are block diagrams showing modified examples of the system 100 for neutralizing ammonia-containing waste liquid and the method for neutralizing ammonia-containing waste liquid according to the first embodiment of the present invention.

[0053] The neutralization treatment system 100 for ammonia-containing waste liquid shown in FIG. 1 may further include a detoxifying agent tank 780 for storing a detoxifying agent (additives for detoxification (hereinafter referred to as "detoxifying agent AD")) and a detoxifying agent supply line 711 for supplying the detoxifying agent AD stored in the detoxifying agent tank 780 to the sludge tank 700 or the waste liquid tank 500, like the neutralization treatment systems 100A and 100B for ammonia-containing waste liquid shown in FIGS. 2 and 3.

[0054] According to this configuration, the neutralization treatment systems 100A, 100B are equipped with a detoxifying agent tank 780 and a detoxifying agent supply line 711, and can detoxify the waste liquid WF by supplying a detoxifying agent AD to the waste liquid WF in the sludge tank 700 or the waste liquid tank 500.

[0055] Thus, the ammonia-containing waste liquid neutralization treatment systems 100A, 100B include a sludge discharge line 160 for discharging sludge SG, one or more waste liquid tanks 500 provided at the end of the sludge discharge line 160, a sludge tank 700 for storing waste liquid WF from the waste liquid tank 500, a waste liquid discharge line 180 for supplying the waste liquid WF to the sludge tank 700, a neutralizing agent supply line 170 for supplying neutralizing agent N to the waste liquid tank 500, and a sensor 720 for measuring the pH of the waste liquid WF in the waste liquid tank 500 or the ammonia concentration of the waste liquid WF.

[0056] According to this configuration, the neutralization processing systems 100A, 100B are equipped with a sensor 720 that measures the pH of the waste liquid WF in the waste liquid tank 500 or the ammonia concentration of the waste liquid WF, and therefore the pH value and ammonia concentration can be measured directly, making it possible to supply an appropriate amount of neutralizing agent N to the waste liquid tank 500.

[0057] 2, the neutralization treatment system 100A is also provided with a detoxifying agent supply line 711 that supplies a detoxifying agent AD containing iron oxide to the sludge tank 700. When citric acid is used as the neutralizing agent N, it is preferable to supply iron oxide as a detoxifying agent to the waste liquid WF. In this configuration, when citric acid and iron oxide are added to the ammonia water AW, ammonium iron citrate is produced, making it possible to render the waste liquid WF harmless.

[0058] 3, the neutralization treatment system 100B is provided with a detoxifying agent supply line 711 that supplies a detoxifying agent AD containing iron oxide to the waste liquid tank 500. In this case, the upstream side of the detoxifying agent supply line 711 is preferably connected to a detoxifying agent tank 780 that stores the detoxifying agent AD. According to this configuration, the neutralization treatment system 100B is provided with the detoxifying agent supply line 711, and thus can supply the detoxifying agent AD to the waste liquid WF in the waste liquid tank 500, thereby detoxifying the waste liquid WF.

[0059] [Second embodiment] FIG. 4 is a block diagram showing a system 100C for neutralizing ammonia-containing waste liquid and a method for neutralizing ammonia-containing waste liquid according to a second embodiment of the present invention.

[0060] The waste liquid tank 500 and the waste liquid discharge line 180 of the first embodiment shown in FIG. 1 may be omitted as in the neutralization treatment system 100C shown in FIG. In this case, the downstream side of the sludge discharge line 160 connected to the purifier 1 is connected to the sludge tank 700. In addition, the downstream side of the neutralizing agent supply line 170 connected to the neutralization tank 600 is connected to the sludge tank 700. Note that the number of sludge discharge lines 160 and purifiers 1 is not limited to one, and there may be multiple sludge discharge lines 160 and purifiers 1. The sludge tank 700 is provided with sensors 720 (pH measuring device 721, ammonia sensor 722, etc.) in the same manner as the waste liquid tank 500 shown in FIG. Even in this case, the neutralization system 100C can achieve the same effects as the neutralization system 100 of the first embodiment.

[0061] 4, the sludge tank 700 of the neutralization treatment system 100C may be provided with an input water supply line 712 for supplying water to the sludge tank 700. In this case, it is preferable to provide a vent line 770 in the sludge tank 700. According to this configuration, the sludge tank 700 is provided with the input water supply line 712, so that the waste liquid WF in the sludge tank 700 can be diluted. In addition, the sludge tank 700 of the neutralization treatment system 100C may be equipped with a detoxifying agent supply line 711 for supplying a detoxifying agent AD, a liquid level measuring device 730 for monitoring the amount (liquid level) of waste liquid WF stored in the sludge tank 700, and a device or structure 740 with an agitation function described below.

[0062] [Third embodiment] FIG. 5 is a diagram showing a system 100D for neutralizing ammonia-containing waste liquid and a method for neutralizing ammonia-containing waste liquid according to a third embodiment of the present invention, and is a schematic diagram showing a sludge tank 700 for storing waste liquid WF.

[0063] As shown in FIG. 5, the waste liquid tank 500 may be provided with a waste liquid discharge line 180, a waste liquid transfer pump 761, a device or structure 740 with an agitation function, a neutralizing agent supply line 170, a sludge discharge line 160, a detoxifying agent supply line 711, an input water supply line 712, a vent line 770, a liquid level measuring device 730, and a sensor 720 (e.g., a pH measuring device 721, an ammonia sensor 722, etc.). Unlike in FIG. 1, a plurality of purifiers 1 are provided.

[0064] The waste liquid discharge line 180 is a flow path for transferring the waste liquid WF in the waste liquid tank 500 to the sludge tank 700. A waste liquid transfer pump 761 is provided in the waste liquid discharge line 180. The waste liquid transfer pump 761 is a pump for transferring the waste liquid WF in the waste liquid tank 500 to the sludge tank 700. In this embodiment, the amount of waste liquid WF stored in the waste liquid tank 500 is measured by a liquid level gauge 730, and the flow rate of the waste liquid discharge line 180 (the discharge rate of the waste liquid transfer pump 761) is controlled according to the amount stored.

[0065] Note that multiple sludge tanks 700, waste liquid discharge lines 180, and waste liquid transfer pumps 761 may be provided depending on the amount of waste liquid WF generated on board the ship. Furthermore, for example, the waste liquid WF can be transferred to any tank depending on the liquid level in the tank using a liquid level gauge 730. Alternatively, for example, the waste liquid WF that overflows from the waste liquid tank 500 may be guided to the sludge tank 700. In this case, the waste liquid transfer pump 761 may be omitted.

[0066] The neutralization treatment system 100D may include one or more sludge tanks 700 for storing neutralized waste fluid WF (Waste fluid). According to this configuration, the neutralization treatment system 100D is provided with one or more sludge tanks 700, and thus can store waste liquid WF generated on board a ship or the like as needed depending on the amount of waste liquid WF.

[0067] A device or structure 740 with an agitation function for agitating the waste liquid WF may be provided within the waste liquid tank 500. The device or structure 740 with an agitation function may be any device or structure that has the function of stirring the waste liquid WF within the waste liquid tank 500, and may be composed of, for example, a stirrer. Note that the device or structure 740 with an agitation function may be provided as appropriate depending on the situation of the waste liquid WF within the waste liquid tank 500, the neutralizing agent N, the detoxifying agent AD to be added to the waste liquid WF, and the like, and may be omitted. According to this configuration, by providing a device or structure 740 with a stirring function in the waste liquid tank 500, the waste liquid WF in the waste liquid tank 500 can be efficiently mixed with the neutralizing agent N or the detoxifying agent AD, thereby making the waste liquid WF harmless.

[0068] Similarly, the sludge tank 700 may be provided with a device or structure 740 having a stirring function for stirring the waste liquid WF. According to this configuration, by providing a device or structure 740 with a stirring function in the sludge tank 700, the waste liquid WF in the sludge tank 700 can be efficiently mixed with the neutralizing agent N and the detoxifying agent AD, thereby making the waste liquid WF harmless.

[0069] As in the first embodiment, the neutralizing agent supply line 170 is a conveying path for supplying the neutralizing agent N into the waste liquid tank 500. In the neutralizing agent supply line 170, the amount of neutralizing agent N corresponding to the measured value of the pH of the waste liquid WF measured by the sensor 720 (for example, a pH meter 721, an ammonia sensor 722, etc.) is sent into the waste liquid tank 500.

[0070] As in the first embodiment, the sludge discharge line 160 is a flow path for discharging the waste liquid WF discharged from the purifier 1 into the waste liquid tank 500. The number of sludge discharge lines 160 and purifiers 1 is not limited to one, and there may be multiple sludge discharge lines 160 and purifiers 1. By providing an appropriate number of sludge discharge lines 160 and purifiers 1, the neutralization treatment system 100D can suitably treat a large amount of waste liquid WF.

[0071] The detoxifying agent supply line 711 is a transport path for supplying the detoxifying agent AD, which detoxifies the waste liquid WF in the waste liquid tank 500, to the waste liquid tank 500. An appropriate detoxifying agent can be selected depending on the components of the waste liquid WF. When the neutralizing agent N is citric acid, the detoxifying agent is preferably iron oxide. The detoxifying agent supply line 711 sends an amount of detoxifying agent AD into the waste liquid tank 500 according to the measured values ​​of the pH, ammonia concentration, etc. of the waste liquid WF measured by the sensor 720. The neutralization treatment system 100D can detoxify the waste liquid WF in the waste liquid tank 500 by providing the detoxifying agent supply line 711 and adding the detoxifying agent AD. The detoxifying agent supply line 711 may be provided as appropriate depending on the components of the waste liquid WF in the waste liquid tank 500, and may be omitted.

[0072] The input water supply line 712 is a flow path for supplying an appropriate amount of water W according to the components, concentration, etc. of the waste liquid WF in the waste liquid tank 500. The neutralization treatment system 100D can dilute the waste liquid WF in the waste liquid tank 500 by providing the input water supply line 712 and adding water. The input water supply line 712 may be provided as appropriate depending on the components and conditions of the waste liquid WF in the waste liquid tank 500, and may be omitted.

[0073] The vent line 770 is a pipe for discharging gas and water vapor in the gas phase of the waste liquid tank 500. The vent line 770 serves to adjust the expansion and contraction of gas caused by changes in the pressure and temperature of the gas in the waste liquid tank 500, and to remove unnecessary gas. The vent line 770 may be provided with a valve, a pump, a filter, etc.

[0074] The liquid level gauge 730 is a gauge for measuring the amount (liquid level) of the waste liquid WF stored in the waste liquid tank 500. By providing the liquid level gauge 730, the waste liquid transfer pump 761 can be driven according to the amount of waste liquid stored in the waste liquid tank 500, and the waste liquid WF can be transferred to the sludge tank 700. The liquid level measuring device 730 may be provided as needed, or may be omitted. In addition, the neutralization treatment system 100D may be provided with a weir instead of the liquid level measuring device 730, so that when the waste liquid WF in the waste liquid tank 500 reaches a predetermined liquid level, it flows (overflows) from the waste liquid discharge line 180 into the sludge tank 700. The sensor 720 is made up of a pH measuring device 721, similar to the first embodiment.

[0075] In this way, the ammonia-containing waste liquid neutralization treatment system 100D is provided with a liquid level measuring device 730 in the waste liquid tank 500, and the neutralized waste liquid WF is transferred to the sludge tank 700 at any time depending on the liquid level of the neutralized waste liquid WF in the waste liquid tank 500.

[0076] According to this configuration, the neutralization treatment system 100D can transfer the neutralized waste liquid WF to the sludge tank 700 according to the liquid level of the waste liquid WF in the waste liquid tank 500. Therefore, if the amount of waste liquid WF stored in the waste liquid tank 500 increases, the waste liquid WF can be automatically sent to the sludge tank 700 as appropriate, thereby efficiently storing a large amount of waste liquid WF.

[0077] [Fourth embodiment] FIG. 6 is a diagram showing a system 100E for neutralizing ammonia-containing waste liquid and a method for neutralizing ammonia-containing waste liquid according to the fourth embodiment, and is a schematic diagram showing a sludge tank 700 for storing the waste liquid WF.

[0078] In the third embodiment, the neutralization treatment system 100D (see FIG. 5) for ammonia-containing waste liquid is described as having one waste liquid tank 500, but a plurality of waste liquid tanks 500A and 500B may be provided, as in the neutralization treatment system 100E shown in FIG. 6. The neutralization treatment system 100E includes multiple waste liquid tanks 500A, 500B and one sludge tank 700. Furthermore, since the amount of waste liquid WF that can be stored can be increased, it can accommodate large ships and large facilities. Furthermore, since neutralization treatment can be performed at multiple locations, treatment of the waste liquid WF can continue even if one of the waste liquid tanks 500A, 500B is unavailable due to maintenance, a malfunction, or the like.

[0079] It is preferable that the two waste liquid tanks 500A, 500B are each provided with a waste liquid discharge line 180, waste liquid transfer pumps 761A, 761B, a device or structure 740 with stirring function, a neutralizing agent supply line 170, a sludge discharge line 160, a detoxifying agent supply line 711, an input water supply line 712, a vent line 770, a liquid level measuring device 730, and a sensor 720 (e.g., a pH measuring device 721, an ammonia sensor 722, etc.).

[0080] The waste liquid WF accumulated in each of the waste liquid tanks 500A, 500B may be transferred from the waste liquid discharge line 180 to the sludge tank 700 by driving the waste liquid transfer pumps 761A, 761B according to the liquid levels in each of the waste liquid tanks 500A, 500B.

[0081] [Variation 1] In the first embodiment, the purifier 1 is a three-phase separation type separation plate centrifuge, but a two-phase separation type separation plate centrifuge may also be used. When a two-phase separation type separation plate centrifuge is used as the purifier 1, it is preferable to provide a pressure sensor 840 that detects the pressure of the ammonia water AW discharged from the heavy liquid extraction section 15 of the purifier 1, and to supply water into the separation chamber of the purifier 1 when the measurement value of the pressure sensor 840 falls below a predetermined value.

[0082] [Variation 2] In the first to fourth embodiments and the first modification, the neutralization treatment systems 100, 100A, 100B, 100C, 100D, and 100E are exemplified as including the purifier 1, but they may not include the purifier 1. Even in this case, the same effects as those of the neutralization treatment systems 100 to 100E of the first to fourth embodiments and the first modification can be achieved. [Explanation of symbols]

[0083] 1 Purifier 100, 100A, 100B, 100C, 100D, 100E Ammonia-containing wastewater neutralization treatment system 160 Sludge discharge line 170 Neutralizer supply line 180 Waste liquid discharge line 500 Waste tank 600 Neutralization Tank 700, 700A, 700B Sludge Tank 701 Treated waste liquid tank 711 Detoxifying Agent Supply Line 712 Input water supply line 720 Sensors 721 pH Meter 722 Ammonia Sensor 730 Liquid level measuring device 740 Devices or structures with stirring function AM Ammonia AW Ammonia water N Neutralizer SG Sludge WF waste liquid

Claims

1. A system for neutralizing ammonia-containing wastewater, which neutralizes ammonia-containing wastewater, one or more sludge tanks; a sludge discharge line for supplying the waste liquid to the sludge tank; a neutralizing agent supply line for supplying a neutralizing agent to the sludge tank; a sensor for measuring the pH of the waste liquid or the ammonia concentration of the waste liquid; Ammonia-containing wastewater neutralization treatment system.

2. a sludge discharge line for discharging sludge; one or more waste tanks provided at the end of the sludge discharge line; a sludge tank for storing the waste liquid from the waste liquid tank; a waste liquid discharge line for supplying the waste liquid to the sludge tank; a neutralizing agent supply line for supplying a neutralizing agent to the waste liquid tank; a sensor for measuring the pH of the waste liquid in the waste liquid tank or the ammonia concentration of the waste liquid; Ammonia-containing wastewater neutralization treatment system.

3. The neutralizing agent has an acidic component.

3. The system for neutralizing ammonia-containing waste liquid according to claim 1 or 2.

4. The sensor is either a pH meter or an ammonia sensor, or both.

3. The system for neutralizing ammonia-containing waste liquid according to claim 1 or 2.

5. The neutralizing agent contains citric acid.

3. The system for neutralizing ammonia-containing waste liquid according to claim 1 or 2.

6. a detoxifying agent supply line for supplying a detoxifying agent containing iron oxide to the sludge tank; 3. The system for neutralizing ammonia-containing waste liquid according to claim 1 or 2.

7. a detoxifying agent supply line for supplying a detoxifying agent containing iron oxide to the waste liquid tank; The system for neutralizing ammonia-containing waste liquid according to claim 2.

8. A device having a stirring function for stirring the waste liquid is provided in the sludge tank. The system for neutralizing ammonia-containing waste liquid according to claim 1.

9. A device having a stirring function for stirring the waste liquid is provided in the waste liquid tank. The system for neutralizing ammonia-containing waste liquid according to claim 2.

10. The sludge tank is provided with a water supply line for supplying water to the sludge tank. The system for neutralizing ammonia-containing waste liquid according to claim 1.

11. The waste liquid tank is provided with a water supply line for supplying water to the waste liquid tank. The system for neutralizing ammonia-containing waste liquid according to claim 2.

12. a liquid level measuring device is provided in the waste liquid tank; transferring the neutralized waste liquid to the sludge tank as needed depending on the liquid level of the neutralized waste liquid in the waste liquid tank; The system for neutralizing ammonia-containing waste liquid according to claim 2.

13. A method for neutralizing an ammonia-containing waste liquid, comprising: The pH or ammonia concentration of the waste liquid is measured with a sensor, adding a neutralizing agent to the waste liquid to neutralize the waste liquid in accordance with either or both of the measured pH value of the waste liquid measured by the sensor and the measured ammonia concentration of the waste liquid; A method for neutralizing ammonia-containing wastewater.

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