JP2004283636A - Sea water desalination apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sea water desalination apparatus capable of satisfactorily eliminating turbid components in sea water and suppressing a decrease in the filtration efficiency with time in a filtration means even when simplifying a pretreatment means, and further, realizing the simplification and miniaturization of the apparatus and the prevention of deterioration of a reverse osmosis membrane by using a prescribed pressurizing means. <P>SOLUTION: This sea water desalination apparatus is provided with the filter means for filtering sea water which is taken in, a pressurizing means for pressurizing and feeding the sea water filtered by the filter means, and a reverse osmosis membrane treatment means for treating the sea water pressurized by the pressurizing means by means of reverse osmosis membrane method. A pretreatment means 13 having a strainer 1a to which a pulse-like application voltage is applied and a filter to which the pulse-like application voltage is applied for passing the sea water passing through the strainer 1a is disposed on the former step of the filter means. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a seawater desalination apparatus using a reverse osmosis membrane, and in particular, a small mobile and portable reverse osmosis membrane desalination apparatus used for homes, well water, fire prevention tanks, seawater pools, small fishing boats, small boats, and the like. About.
[0002]
[Prior art]
As a seawater desalination method, an evaporation method by evaporating seawater and condensing purified water vapor, a reverse osmosis membrane method of obtaining freshwater by passing seawater through a reverse osmosis membrane under pressure, other electrodialysis methods, There are a vapor compression method, a multi-stage flash method, a multiple effect method, and the like. In particular, the reverse osmosis membrane method has advantages such as easy operation as compared with the evaporation method, and is used in many seawater desalination apparatuses. .
[0003]
Generally, in a large-sized seawater desalination apparatus using a reverse osmosis membrane, a sterilization process in which chlorine or the like is added to the seawater withdrawn before the treatment step using the reverse osmosis membrane in order to prevent the growth of microorganisms inside the apparatus. And a coagulation-sedimentation process for removing suspended components in seawater to prevent membrane contamination, and a pretreatment process having a sand filtration means. However, in the case of seawater desalination equipment mounted on small vessels, etc., since the whole desalination equipment tends to be smaller and lighter, the pretreatment process is simplified, and a filter may be provided before the reverse osmosis membrane treatment step. Alternatively, the seawater taken out is clarified by attaching a strainer to the seawater intake and supplied to the reverse osmosis membrane treatment step.
Further, in the reverse osmosis membrane method, the water to be treated is supplied to the reverse osmosis membrane treatment step by pressurizing the water to about 5.5 to 6 MPa, but in a large-sized seawater desalination apparatus, the seawater taken separately from the seawater pump is not used. A pressurizing pump for pressurizing the seawater is provided, the seawater is pumped up by a vacuum pump, the seawater is collected in a tank, and the seawater is added to the reverse osmosis membrane treatment device using a pump with little pulsation such as a spiral pump. It is configured to pump water. On the other hand, a small-sized seawater desalination apparatus is generally configured so that seawater is pumped by a single vacuum pump and pressurized water to be subjected to reverse osmosis membrane treatment is pressurized. I am planning.
[0004]
[Patent Document 1]
JP-A-10-230259 [Patent Document 2]
JP-A-1-99612 [0005]
[Problems to be solved by the invention]
However, when the pretreatment step is simplified as described above, the removal of turbidity contained in seawater tends to be insufficient, and it is not possible to completely prevent the invasion and propagation of microorganisms in the apparatus, and therefore, the reverse osmosis membrane Has been contaminated, the processing efficiency has been reduced, and the life of the film has been shortened. When a strainer is provided at the seawater intake, there has been a problem that marine organisms such as shellfish adhere to the strainer, and water intake efficiency is reduced.
[0006]
Further, when the vacuum pump is provided in the preceding stage of the reverse osmosis membrane processing apparatus, for example, when suddenly stopped during operation of the water supply pump, particularly when the pump and the reverse osmosis membrane processing apparatus suddenly overload state. There is a problem that the so-called "water hammer" shortens the life of the reverse osmosis membrane. However, if an accumulator having a pressure accumulating function is installed for that purpose, there is a fear that the device configuration becomes complicated and large.
[0007]
Further, as means for reducing the size of the apparatus, there is a method of increasing the torque of the pressurizing pump, but a booster such as a large pulley is required. However, the problem with large pulleys is that the risk of accidents such as pinching of fingers by workers is high, and the efficiency of processing from seawater to desalination is reduced due to energy loss due to slippage due to wear of the pulley belt. was there.
[0008]
In addition, when the seawater freshwater equipment is used by general users, such as fishermen and other shipboard workers, it is difficult to thoroughly maintain and manage the equipment, such as washing with fresh water and filling in sterilizing agents. In some cases, microorganisms and germs proliferate in the water or the filter, and even if the seawater desalination apparatus is operated again, the obtained permeated water (freshwater) cannot be used as it is.
[0009]
In a small-sized seawater desalination apparatus, the pressure of the piston must be reduced with low power consumption.Therefore, the diameter of the piston in the pump is designed to be small. There was also a problem that the wear of the steel could be continuously continued normally for only several hours.
[0010]
Therefore, the present invention aims to provide a seawater desalination apparatus that can reduce the size and simplify the seawater desalination apparatus using the reverse osmosis membrane method and that can prevent membrane deterioration of the reverse osmosis membrane even if the accumulator is omitted. is there.
[0011]
[Means for Solving the Problems]
Such an object is achieved by the present invention described in the following (1) to (5).
(1) filtration means for filtering the seawater withdrawn;
Pressurizing means to pressurize and send the seawater filtered by the filtering means,
A reverse osmosis membrane treatment means for treating seawater pressurized by the pressurization means by a reverse osmosis membrane method, and a seawater desalination apparatus,
A pre-treatment unit having a strainer to which a pulse-like applied voltage is applied in a stage preceding the filtering unit, and a filter to which a pulse-like applied voltage is applied to pass seawater passing through the strainer, is provided. Seawater desalination equipment.
(2) filtering means for filtering the seawater withdrawn;
Pressurizing means to pressurize and send the seawater filtered by the filtering means,
A reverse osmosis membrane treatment means for treating seawater pressurized by the pressurization means by a reverse osmosis membrane method, and a seawater desalination apparatus,
A seawater desalination apparatus comprising: a pretreatment unit having a strainer to which a half-wave rectified DC voltage is applied and a filter to which a half-wave rectified DC voltage is applied, in front of the filtering unit.
(3) filtration means for filtering the seawater withdrawn;
Pressurizing means to pressurize and send the seawater filtered by the filtering means,
A reverse osmosis membrane treatment means for treating seawater pressurized by the pressurization means by a reverse osmosis membrane method, and a seawater desalination apparatus,
A strainer to which an AC static voltage is applied before the filtration means,
A seawater desalination apparatus, comprising: a pretreatment unit having a filter to which an AC static voltage is applied.
(4) filtration means for filtering the seawater withdrawn;
Pressurizing means to pressurize and send the seawater filtered by the filtering means,
A reverse osmosis membrane treatment means for treating seawater pressurized by the pressurization means by a reverse osmosis membrane method, and a seawater desalination apparatus,
As the pressurizing means, a plunger pump capable of supplying water while maintaining a basic torque of the motor from 1/20 to 1.5 times the rotation speed using an inverter capable of controlling a magnetic flux vector as a pump motor is used. A seawater desalination apparatus characterized by the above-mentioned.
(5) filtering means for filtering the seawater withdrawn;
Pressurizing means to pressurize and send the seawater filtered by the filtering means,
A reverse osmosis membrane treatment means for treating seawater pressurized by the pressurization means by a reverse osmosis membrane method, and a seawater desalination apparatus,
As the pressurizing means, a plunger pump capable of supplying pressure water at a low rotation speed while providing a reduction gear to a pump motor and doubling the basic torque of the motor from 1/20 to 1/5 is used. Seawater desalination equipment.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a seawater desalination apparatus of the present invention will be described based on a preferred embodiment shown in the accompanying drawings.
FIG. 1 shows an embodiment of the seawater desalination apparatus of the present invention. As shown in this figure, the seawater desalination apparatus of the present invention comprises a filtering means 2 for filtering the seawater withdrawn, a pressurizing means 3 for pressurizing and sending the seawater filtered by the filtering means, A reverse osmosis membrane treatment means 5 for treating seawater pressurized by a reverse osmosis membrane method, and a strainer in which a pulse-like applied voltage is applied to a stage preceding the filtration means 2 and which has passed through the strainer. And a filter to which a pulsed applied voltage for passing seawater is applied.
[0013]
With such a configuration, the turbid components in the seawater are removed by the pretreatment means in advance, so that the reverse osmosis membrane is not clogged and the life of the reverse osmosis membrane is prevented from being shortened. Sustainability can be improved.
[0014]
As shown in FIG. 1, reference numeral 1 denotes a primary filtration unit including a metal strainer and a filter, reference numeral 2 denotes a filtration unit, reference numeral 3 denotes a pressurizing unit, reference numeral 4 denotes a pressure gauge, reference numeral 5 denotes a reverse osmosis membrane treatment device, and reference numeral. Reference numeral 8 denotes a check valve, and reference numeral 9 denotes a needle valve.
[0015]
The seawater is pumped up by the suction force of a pressurizing pump constituting the pressurizing unit 3, the fine particles such as turbid components and microorganisms are removed from the primary filtering unit 1 through the filtering unit 2, and sent to the reverse osmosis membrane treatment device 5. Is done. In the subsequent stage of the reverse osmosis membrane treatment device 5, a treated water pipe 6 for taking out desalinated treated water and a discharge pipe 7 for discharging concentrated waste water in which sodium chloride or the like is concentrated are connected. 8. The discharge pipe 7 is provided with a needle valve 9. The taken-in seawater is pressurized to a predetermined pressure by opening and closing the needle valve 9 provided on the pressurizing means 3 and the discharge pipe 7, and is supplied to the reverse osmosis membrane treatment device 5. A treated water pipe 10 for supplying treated water is connected to a stage preceding the reverse osmosis membrane treatment apparatus 5, and the pressure gauge 4 for monitoring the water pressure and the amount of water supplied to the reverse osmosis membrane treatment apparatus 5 are monitored on the treated water pipe 10. A raw water alarm device 11 is provided. In addition, the pressure is adjusted by opening and closing the needle valve 9 as necessary, and when the raw water is not sent to the water pipe 10 to be treated, the raw water alarm device 11 is operated.
[0016]
As shown in FIGS. 2 and 3, the pretreatment means 13 of the present embodiment is a primary filter configured as a cartridge type filter in which, for example, a cylindrical metal strainer 1a is used as an outer cylinder, and a filter element 1b is combined inside. Through a filter 1 and a lid 1e attached to the upper part of the strainer 1a to seal seawater from being mixed into the filtered water, and a conductive wire 1d connected to a hook 1c provided on the lid 1e. And means 1f for applying a voltage or current to the strainer 1a and the filter element 1b, and a float 1h fixed by a chain 1g extending from the hook 1c. In addition, one end of a treated water supply pipe 10 for supplying the primary filtered seawater to the filtration means 2 is connected near the center of the lid 1e.
[0017]
The strainer 1a has a hollow cylindrical shape, and its outer surface is preferably formed in a mesh shape having a hole diameter of, for example, 0.01 to 3 mm, preferably 0.05 to 0.3 mm. With such a shape, turbid components can be efficiently removed from seawater without excessive resistance. As the constituent material of the strainer, it is preferable to use a corrosion-resistant metal such as stainless steel or titanium, or it is preferable that a coating layer mainly composed of a precious metal material such as platinum or gold is formed on these metal materials. . By using such a material, elution of metal ions can be suppressed.
[0018]
It is preferable to use a filter having a pore diameter of 0.1 μm or more, preferably 1 μm to 100 μm, as the filter element 1b. By setting the pore diameter in this range, the turbid components in the seawater can be satisfactorily removed without applying an excessive load to the filter element. Further, as a constituent material of the filter element, for example, cellulose, cellulose acetate, cellulose diacetate, polycarbonate, polyamide, polysulfone, polyethersulfone, polyolefin, vinylidene fluoride, polyvinylidene fluoride, polytetrafluoroethylene, polyethylene, polypropylene, Any material such as polyacrylonitrile, polybenzoxazinedione, polyvinyl alcohol, modacrylic, polybenzimidazolone, glass fiber, ceramic, and activated carbon can be used.
[0019]
The shape of the filter element 1b is not particularly limited, and any shape such as a hollow fiber, a pleat, and a wind can be used. Among them, a filter obtained by press-molding a nonwoven fabric made of polypropylene and polyester has a pore size of 0%. Since it can be reduced to about 1 μm, it is particularly preferably used as the filter element of the present invention.
[0020]
The seawater first removes relatively large contaminants by passing through a metal strainer 1a, and then passes through a filter element 1b to remove fine particles. With such a configuration, the number of suspended components and microorganisms in the water to be treated passing through the reverse osmosis membrane means 5 is reduced, and the clogging of the reverse osmosis membrane is prevented, in cooperation with the filtration means 2 at the subsequent stage. The load on the reverse osmosis membrane can be reduced, and shortening of the membrane life can be prevented.
In addition, it is good also as a structure which separately provides a cartridge type filter etc. between the primary filtration means 1 and the filtration means 2.
[0021]
A pulse-like applied voltage is applied to the primary filtering means 1 by an applying means 1f. The application of negative and positive pulse voltages to the metal strainer 1a can prevent negatively charged microorganisms and the like from adhering to the strainer. Further, when the strainer is positively charged, heavy metal ions in seawater are less likely to adhere due to the repulsive force between the positive charges, so that intrusion of microorganisms, heavy metal ions, and the like into the inside of the device can be suppressed. Further, by applying a pulse-like applied voltage, the occurrence of a short circuit (short circuit) can be suppressed.
[0022]
In addition, by combining the metal strainer 1a to which the pulse-like applied voltage is applied and the filter element 1b, the ability to remove the turbid components in seawater can be further enhanced, and the life of the reverse osmosis membrane can be effectively shortened. Can be prevented.
[0023]
The pulse-like applied voltage is preferably 0.1 to 5 V as a DC voltage, and more preferably 0.5 to 2 V. Further, it is preferable that the pulse period is reversed between positive and negative at an interval of 0.1 to 10 seconds and a DC voltage is applied for 0.1 to 3 seconds. When the applied voltage is less than 0.1 V, a sufficient effect cannot be obtained. On the other hand, when the applied voltage exceeds 5 V, seawater may be electrolyzed to generate chlorine gas. Further, after applying a negative voltage to the strainer 1a for a certain period of time, by inverting the voltage and applying a positive voltage for a certain period of time, attached components such as scale components in seawater can be desorbed, and the metal strainer 1a is clogged. Can also be prevented. In addition, the invasion and propagation of microorganisms into the device can be suppressed, and as a result, the amount of microorganisms contained in the water to be treated supplied to the reverse osmosis membrane treatment device 5 can be reduced, and the load on the reverse osmosis membrane can be reduced. Can be planned.
[0024]
In addition, by applying a negative pulse voltage to the water to be treated, an effect of improving the water permeability of the reverse osmosis membrane treatment device can be obtained.
[0025]
As the filtration means 2 provided at the subsequent stage of the primary filtration means 1, it is preferable to use a small cartridge type filter which is not particularly limited but is easily replaced. Any cartridge type filter can be used, for example, cellulose, cellulose acetate, cellulose diacetate, polycarbonate, polyamide, polysulfone, polyethersulfone, polyolefin, vinylidene fluoride, polyvinylidene fluoride, polytetrafluoroethylene Any one of polyethylene, polypropylene, polyacrylonitrile, polybenzoxazinedione, polyvinyl alcohol, modacrylic, polybenzimidazolone, glass fiber, ceramic, activated carbon and the like can be used. For example, hollow fiber type, pleated type, and wind type filter elements made of polypropylene, polysulfone, polyester, activated carbon and the like are commercially available, but those made of activated carbon are particularly preferred because of their high deodorizing effect.
[0026]
The reverse osmosis membrane treatment device 5 provided at the subsequent stage of the pressurizing means 3 described below can be composed of any reverse osmosis membrane element such as acetylcellulose, aromatic polyamide, polyether, and aliphatic polyamide, As the shape of the membrane module, any shape such as a flat membrane, a spiral, a hollow fiber, and a tube can be used. A treatment water pipe 6 and a drainage pipe 7 are connected to the subsequent stage of the reverse osmosis membrane treatment apparatus 5, and sodium chloride, magnesium, and the like are removed by the reverse osmosis membrane treatment. Taken out. On the other hand, the concentrated wastewater in which the salts in the seawater are concentrated is discharged from the discharge pipe 7 to the outside of the apparatus.
[0027]
Further, the seawater desalination apparatus of the present invention includes a pretreatment unit having a strainer to which a half-wave rectified DC voltage is applied and a filter to which a half-wave rectified DC voltage is applied, in a stage preceding the filtering unit 2. It is characterized by the following.
[0028]
By applying a half-wave rectification DC voltage, which is a kind of pulse current, to the metal strainer 1a, it is possible to prevent negatively charged microorganisms and the like from adhering to the strainer, and to prevent heavy metal ions in seawater from being positively charged. Are less likely to adhere, and the invasion of microorganisms into the device can be suppressed. In addition, by combining a strainer to which a half-wave rectified DC voltage is applied with a filter, the ability to remove suspended components in seawater can be increased, and a reduction in membrane life can be effectively prevented. Further, by applying a half-wave rectified DC voltage, occurrence of a short circuit (short circuit) can be suppressed.
[0029]
The applied voltage is preferably a half-wave rectified DC voltage of 0.1 to 5 V, and more preferably 0.5 to 2 V. When the applied voltage is less than 0.1 V, a sufficient effect cannot be obtained. On the other hand, when the applied voltage exceeds 5 V, seawater may be electrolyzed to generate chlorine gas. Since microorganisms are usually negatively charged, adhesion of microorganisms, marine organisms such as shellfish and wisteria jars is suppressed by applying a negative voltage to the strainer 1a. Further, after applying a negative voltage for a certain period of time, by inverting the voltage and applying a positive voltage to the strainer 1a, it is possible to remove attached components such as scale components in seawater, thereby preventing clogging. The water permeability of the strainer can be ensured. In addition, it is possible to suppress the invasion and propagation of microorganisms into the device, and to reduce the amount of microorganisms contained in the water to be treated supplied to the reverse osmosis membrane treatment device 5. In addition, by applying a negative voltage to the water to be treated, an effect of improving water permeability in the reverse osmosis membrane can be obtained.
[0030]
In still another embodiment of the present invention, a pre-processing means having a strainer applied with an AC static voltage at the preceding stage of the filtering means and a filter having an applied AC static voltage at the preceding stage of the filtering means, and I do.
[0031]
By applying an AC static voltage to the metal strainer 1a, microorganisms and the like are prevented from adhering to the strainer, and heavy metal ions in seawater are less likely to adhere, and the invasion of microorganisms and heavy metal ions into the apparatus is suppressed. can do. In addition, by combining the metal strainer to which the AC electrostatic voltage is applied and the filter to which the AC electrostatic voltage is applied, the ability to remove the turbid components in the seawater can be further improved, thereby improving the life of the reverse osmosis membrane. Can be prevented from being shortened.
[0032]
In the present embodiment, the primary filtration means 1 includes a metal strainer to which an electrostatic voltage is applied at a frequency of 5 to 250 Hz, a voltage of 0.5 to 5 V, and a current of 0.3 to 3.6 mA in an AC circuit by an applying means 1f; It is preferable to use a filter having a frequency of 5 to 250 Hz, a voltage of 0.5 to 5 V, and a current of 0.3 to 3.6 mA to which an electrostatic voltage is applied. More preferably, a static voltage is preferably applied within a range of a frequency of 8 to 200 Hz, a voltage of 1.0 to 4 V, and a current of 0.3 to 3 mA. When the applied voltage is less than 0.5 V, a sufficient effect cannot be obtained. On the other hand, when the applied voltage exceeds 5 V, seawater is electrolyzed, and chlorine gas or hydrogen gas may be generated.
[0033]
Since microorganisms are usually negatively charged, by applying an alternating static voltage to the strainer 1a, it is possible to prevent adhesion of microorganisms, marine organisms such as shellfish and wisteria jars, and to avoid clogging. . Furthermore, because of the AC voltage, attached components such as scale components in the seawater can be desorbed, so that the entry of microorganisms into the device can be prevented, the propagation of microorganisms in the device can be suppressed, and reverse osmosis can be achieved. The amount of microorganisms contained in the water to be treated supplied to the membrane treatment device can also be reduced. In addition, the effect of improving the water permeability of the reverse osmosis membrane treatment device can be obtained by applying an electrostatic voltage to the water to be treated.
[0034]
The seawater desalination apparatus of the present invention is a filtering means for filtering the seawater withdrawn, a pressurizing means for pressurizing and sending the seawater filtered by the filtering means, and a reverse osmosis membrane for the seawater pressurized by the pressurizing means. And a reverse osmosis membrane treatment means for treating by a method, wherein an inverter capable of controlling a magnetic flux vector is used as a pump motor as the pressurizing means, and a rotation speed is reduced from 1/20 to 1. It is characterized by using a plunger pump capable of supplying water under pressure while maintaining the basic torque of the motor up to five times.
[0035]
By using such a pressurizing means, the raw water (seawater) can be raised to a desired pressure, and the self-priming and pressurization of seawater can be covered by one pump. Further, by using the three-cylinder plunger pump 31, the pressure of the raw water can be smoothly and variably controlled, and the pulsation can be absorbed to reduce the rapid pressure fluctuation to the reverse osmosis membrane, thereby effecting the membrane deterioration. Can be suppressed.
[0036]
FIG. 4 shows an example of the pressing means 3 of the present invention. The pressurizing means 3 includes a pressurizing pump 31 composed of a three-cylinder plunger pump, and a magnetic flux vector control type constant torque motor 32. The motor 32 uses a magnetic flux vector inverter to reduce the rotation speed from 1/20. It is possible to vary up to 1.5 times.
[0037]
In other words, this makes it possible to produce a plunger pump capable of supplying water at a pressure of 6 Mpa with low power consumption while maintaining the basic torque of the motor. With a conventional plunger pump, the pumping capacity up to the pump is about 0.3 m to 1 m. However, since the rotation speed of the plunger pump can be increased by 1.5 times by the inverter until the self-priming of seawater, the pump lifting capacity can be pumped up to about 20 m.
[0038]
Further, the pressurizing ability and the self-priming ability are improved by a factor of five with the power consumption of one tenth of the power consumption of the conventional high-pressure pump. Conventionally, deceleration by a belt pulley was necessary to maintain the rotational torque. However, this device does not require a belt pulley, so there is no danger of a roll-in accident during rotation of the belt pulley, and the device can be downsized. Thus, safety can be improved and operation with low power consumption can be performed.
[0039]
In addition, it is also possible to replace the pressure means with a pump having no pulsation such as a spiral pump. However, in this case, although no accumulator is required, it is preferable to provide a pump for pumping seawater in addition to the pressurizing means 3.
[0040]
As another mode of the pressurizing means of the present invention, a pump motor is provided with a reduction gear, and the pressure water is supplied at a low rotation speed while doubling the basic torque of the motor from 1/20 to 1/5. It is characterized by using a possible plunger pump.
[0041]
FIG. 5 shows the pressurizing means of this embodiment. The pressurizing means 3 includes a pressurizing pump 31 composed of a three-cylinder plunger pump, and a reduction gear 34 as a motor for the pressurizing pump. This enables low-rotation, for example, 6 Mpa pressure water supply while doubling the basic torque of the motor from 1/20 to 1/5 the rotation speed, but assuming a long-term continuous operation of the motor, 60 Hz, It is desirable that the rotation speed is 1/10 of 1750 rotations of the four poles or about 175 rotations. Further, unlike the conventional small-sized seawater desalination apparatus, since the deceleration by the belt pulley is not required to maintain the rotating torque, the apparatus can be reduced in size, simplified and without danger of a roll-in accident during rotation of the belt pulley. Operation with low power consumption is now possible.
[0042]
FIG. 6 shows still another embodiment of the pressurizing means 3. An electric motor, which is a driving device for driving the pressurizing pump, and a one-cylinder or two-cylinder oilless eccentric type plunger pressurizing pump are built in the container 36, and water can be supplied at a pressure of 6.0 MPa. It is possible. Further, an accumulator 37 is provided, and is configured to absorb pulsation by its pressure accumulating function. With this configuration, it is possible to prevent the reverse osmosis membrane from deteriorating due to the pulsation of the pump. In addition, assuming a long-term continuous operation of the motor, it is preferable that the accumulator is mounted at a rotation speed of 1740 rotations. When water to be treated at 1 t / day is supplied under pressure to the reverse osmosis membrane treatment device at 6 Mpa, the power consumption of the pump, which was conventionally required at about 20 kW / hour, can be reduced to about 200 w / h. Since the power consumption is low as described above, the electric motor can be driven by a solar panel.
[0043]
【The invention's effect】
As described above, the seawater desalination apparatus of the present invention can sufficiently remove turbid components in seawater even if the pretreatment means is simplified, and the filtration efficiency in the filtration means such as a reverse osmosis membrane is improved. Can be suppressed, and the amount of permeated water can be dramatically increased. In addition, the propagation of microorganisms in the apparatus can be suppressed, and a decrease in the life of the membrane can be prevented. Further, the seawater desalination apparatus of the present invention can transmit water at a desired pressure with low power consumption by using a predetermined pressurizing means. In addition, the apparatus of the present invention required deceleration by a belt pulley to maintain the rotational torque.However, since such a belt pulley is not required, there is no danger of a roll-in accident during the rotation of the belt pulley, and the Small size and low power consumption operation became possible.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing an example of a seawater desalination apparatus of the present invention.
FIG. 2 is an exploded view showing a primary filtration means of the seawater desalination apparatus of the present invention.
FIG. 3 is an overall perspective view showing a pretreatment means of the seawater desalination apparatus of the present invention.
FIG. 4 is a side view showing one embodiment of a pressurizing means of the seawater desalination apparatus of the present invention.
FIG. 5 is a side view showing another embodiment of the pressurizing means of the seawater desalination apparatus of the present invention.
FIG. 6 is a perspective view showing still another embodiment of the pressurizing means of the seawater desalination apparatus of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Primary filtration means 1a Strainer 1b Filter element 1f Applying means 2 Filtration means 3 Pressurization means 31 Plunger pump 32 Motor 34 Reduction gear 36 Container 37 Accumulator 4 Pressure gauge 5 Reverse osmosis membrane processing means 13 Pretreatment means

Claims (5)

A filtering means for filtering the seawater withdrawn,
Pressurizing means to pressurize and send the seawater filtered by the filtering means,
A reverse osmosis membrane treatment means for treating seawater pressurized by the pressurization means by a reverse osmosis membrane method, and a seawater desalination apparatus,
A strainer to which a pulsed applied voltage is applied in a stage preceding the filtering means,
A filter to which a pulsed applied voltage for passing seawater passing through the strainer is applied,
A seawater desalination apparatus provided with a pretreatment means having: A filtering means for filtering the seawater withdrawn,
Pressurizing means to pressurize and send the seawater filtered by the filtering means,
A reverse osmosis membrane treatment means for treating seawater pressurized by the pressurization means by a reverse osmosis membrane method, and a seawater desalination apparatus,
A strainer to which a half-wave rectified DC voltage is applied in a stage preceding the filtering means,
A filter to which a half-wave rectified DC voltage is applied;
A seawater desalination apparatus provided with a pretreatment means having: A filtering means for filtering the seawater withdrawn,
Pressurizing means to pressurize and send the seawater filtered by the filtering means,
A reverse osmosis membrane treatment means for treating seawater pressurized by the pressurization means by a reverse osmosis membrane method, and a seawater desalination apparatus,
A strainer to which an AC static voltage is applied before the filtration means,
A filter to which an AC static voltage is applied,
A seawater desalination apparatus provided with a pretreatment means having: A filtering means for filtering the seawater withdrawn,
Pressurizing means to pressurize and send the seawater filtered by the filtering means,
A reverse osmosis membrane treatment means for treating seawater pressurized by the pressurization means by a reverse osmosis membrane method, and a seawater desalination apparatus,
As the pressurizing means, a plunger pump capable of supplying water while maintaining a basic torque of the motor from 1/20 to 1.5 times the rotation speed using an inverter capable of controlling a magnetic flux vector as a pump motor is used. A seawater desalination apparatus characterized by the above-mentioned. A filtering means for filtering the seawater withdrawn,
Pressurizing means to pressurize and send the seawater filtered by the filtering means,
A reverse osmosis membrane treatment means for treating seawater pressurized by the pressurization means by a reverse osmosis membrane method, and a seawater desalination apparatus,
As the pressurizing means, a plunger pump capable of supplying pressure water at a low rotation speed while providing a reduction gear to a pump motor and doubling the basic torque of the motor from 1/20 to 1/5 is used. Seawater desalination equipment.

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