JP2022038173A - Oil-containing wastewater separator and its method - Google Patents

Abstract

To provide a separator that can achieve both improved treatment efficiency and space saving when separating oil-containing wastewater from oil-containing scum.SOLUTION: An ultrasonic vibrator 4 is installed in a storage tank 2 so that an upper surface 4a of the ultrasonic vibrator 4 has an inclination angle of 20 degrees with respect to a liquid surface of an oil-containing scum Scoil. This prevents oil-containing drainage water Woil (separated water) separated from the oil-containing scum Scoil from remaining on the top surface 4a. In other words, since the oil-impregnated scum Scoil is always present on the upper surface 4a of the ultrasonic transducer 4, it is possible to promote the separation of the oil-containing drainage Woil (separated water) and dust from the oil-containing scum Scoil due to the cavitation effect. Since the ultrasonic transducer 4 is only installed in the storage tank 2, the oil-containing drainage Woil (separated water) and dust can be separated from the oil-containing scum Scoil with a space-saving and simple structure.SELECTED DRAWING: Figure 1

Description

The present invention relates to an oil-impregnated wastewater separation device for reducing the volume of oil-containing scum and a method thereof.

According to Japanese Patent Application Laid-Open No. 2011-45846 (Patent Document 1), an oil-impregnated scum separated from oil-impregnated wastewater generated in an iron-making factory is subjected to a multi-stage vibrating sieve having different openings to obtain moisture (patent-containing scum). A device for separating (oil-impregnated wastewater) to reduce the volume is described. With this device, it is possible to reduce the volume of scum without using a lot of chemicals and heat energy.

Japanese Unexamined Patent Publication No. 2011-45846

However, since the oil-impregnated wastewater separation device described in the above-mentioned publication needs to arrange a plurality of vibrating sieves, a large installation space is required, and it is still possible to improve the treatment efficiency and save space. There is room for improvement.

The present invention has been made in view of the above, and an object of the present invention is to provide a technique that contributes to both improvement of treatment efficiency and space saving when separating oil-containing wastewater from oil-containing scum.

According to the preferred embodiment of the oil-containing wastewater separation device according to the present invention, the oil-containing wastewater separation device for reducing the volume of the oil-containing scum is configured. The oil-impregnated drainage separation device includes a storage tank capable of storing oil-impregnated scum, an oscillator, and an oscillator electrically connected to the oscillator so as to be able to supply high-frequency power to the oscillator. The oscillator has an upper surface facing the liquid surface side of the oil-containing scum, and is arranged in the storage tank with the upper surface inclined by a predetermined angle with respect to the liquid surface of the oil-containing scum.

According to the present invention, fine bubbles can be generated in the oil-containing scum by the ultrasonic waves generated by the vibrator, and cavitation can be positively caused by the change in sound pressure. As a result, moisture (oil-containing drainage), dust, and the like can be effectively separated from the oil-containing scum by the impact pressure generated when the fine bubbles adhering to the oil-containing scum disappear (collapse). Since the upper surface of the oscillator is inclined at a predetermined angle with respect to the liquid surface of the oil-containing scum, the water (oil-containing drainage) separated from the oil-containing scum does not stay on the upper surface. That is, since the oil-impregnated scum can always be present on the upper surface of the oscillator, it is possible to promote the separation of water (oil-impregnated drainage) and dust from the oil-containing scum due to the cavitation effect. Further, since the upper surface of the oscillator is only tilted at a predetermined angle with respect to the liquid surface of the oil-containing scum, moisture (oil-containing drainage) and dust can be separated from the oil-containing scum with a space-saving and simple structure.

According to a further embodiment of the oil-impregnated drainage separation device according to the present invention, the upper surface of the oscillator has an inclination angle of 15 degrees or more and 25 degrees or less, preferably about 20 degrees with respect to the liquid surface.

As a result of diligent research, the present inventor has found that the reduction rate of oil-containing scum becomes high when the inclination angle of the upper surface of the oscillator with respect to the liquid surface is 15 degrees or more and 25 degrees or less, preferably about 20 degrees. Here, the reduction rate is defined as the volume reduction rate due to the removal of water (oil-impregnated wastewater) from the oil-impregnated scum, and specifically, "oil-containing before volume reduction (before treatment) in the storage tank". The value obtained by subtracting the "volume of the oil-containing scum after volume reduction (after treatment) in the storage tank" from the "volume of scum" is divided by the "volume of oil-containing scum before volume reduction (before treatment) in the storage tank". After that, it is defined as a value multiplied by 100. Based on the results of this research, in this embodiment, the inclination angle of the upper surface of the vibrator with respect to the liquid surface is set to 15 degrees or more and 25 degrees or less, preferably about 20 degrees. Thereby, the volume reduction of the oil-containing scum can be further promoted.

According to a further embodiment of the oil-impregnated drainage separation device according to the present invention, the oscillator is arranged in the storage tank so that the distance between the portion of the upper surface closest to the liquid level and the liquid level is 5 cm or more. ing.

As a result of diligent research, the present inventor, as a result of diligent research, when the distance between the upper surface of the oscillator and the liquid surface of the oil-containing scum is narrow, the vibration of the liquid surface of the oil-containing scum becomes intense, and the oil-containing scum separated by the effect of ultrasonic waves is produced. We have found that a phenomenon such as instant remixing occurs. Based on the results of this research, in this embodiment, the distance between the upper surface of the oscillator and the liquid level of the oil-containing scum is set to 5 cm or more. As a result, it is possible to suppress the reduction of the volume reduction effect of the oil-containing scum.

According to a further embodiment of the oil-impregnated wastewater separation device according to the present invention, the storage tank has a bottom surface. Then, the oscillator is arranged in the storage tank so as to have a space between the oscillator and the bottom surface.

According to this embodiment, the water (oil-impregnated drainage) separated from the oil-containing scum flows into the space between the vibrator and the bottom surface, and the oil-containing scum can be moved to the upper surface side of the vibrator by the convection effect. Further, it is possible to satisfactorily prevent the oscillator from being buried in the water (oil-impregnated drainage) separated from the oil-containing scum. This makes it possible to further promote the separation of water (oil-impregnated drainage) and dust from the oil-impregnated scum due to the cavitation effect.

According to a further embodiment of the oil-impregnated wastewater separator according to the present invention, the ultrasonic frequency output to the oil-containing scum is 20 kHz or more and 100 kHz or less, preferably about 40 kHz.

As a result of diligent research, the present inventor has found that water (oil-containing wastewater) and dust can be effectively separated from oil-containing scum in a specific ultrasonic frequency band. Based on the results of this research, in this embodiment, the ultrasonic frequency output to the oil-containing scum is set to 20 kHz or more and 100 kHz or less, preferably about 40 kHz. As a result, moisture (oil-impregnated drainage) and dust can be effectively separated from the oil-impregnated scum.

According to a further embodiment of the oil-impregnated wastewater separation device according to the present invention, the oil-containing scum stored in the storage tank is 20 L or more and 30 L or less, preferably 30 L, and the high-frequency power is 400 W or more and 600 W or less, preferably 600 W. be. That is, the oscillator supplies high frequency power of 20 W or more and 30 W or less, preferably 20 W, per 1 L of oil-containing scum to the oscillator.

As a result of diligent research, the present inventor has found that there is a correlation between the value of high-frequency power supplied to the oscillator and the amount of oil-containing scum to be processed. When the output is made larger than 600 W, the water quality of the separated water (oil-containing wastewater) deteriorates. On the other hand, if the output is less than 400 W, the processing time becomes long. Based on the results of this research, in this embodiment, the amount of oil-containing scum is 20 L or more and 30 L or less, preferably 30 L, and the high-frequency power supplied to the vibrator is 400 W or more and 600 W or less, preferably 600 W. That is, the oscillator is configured to supply high frequency power of 20 W or more and 30 W or less, preferably 20 W per 1 L of oil-containing scum to the oscillator. This makes it possible to more effectively separate water (oil-impregnated drainage) and dust from the oil-impregnated scum.

According to a further embodiment of the oil-impregnated wastewater separator according to the present invention, a temperature controller capable of adjusting the temperature of the oil-containing scum to 10 ° C. or higher and 40 ° C. or lower is further provided.

As a result of diligent research, the present inventor found that if the temperature of the oil-containing scum is too low, the viscosity of the oil-containing scum becomes high, and clogging occurs when the oil-containing scum after separation (after volume reduction) is processed. If the temperature of the oil-containing scum is too high, the separation effect will be improved, but the concentrated (volume-reduced) oil-containing scum and floating oil will be more easily dissolved in the oil-containing wastewater due to the effect of ultrasonic waves, and the separation effect will be improved. Was found to decrease. Based on the results of this research, in the present invention, the temperature of the oil-containing scum is adjusted to 10 ° C. or higher and 40 ° C. or lower. This makes it possible to more effectively separate water (oil-impregnated drainage) and dust from the oil-impregnated scum.

According to a preferred embodiment of the oil-containing wastewater separation method according to the present invention, an oil-containing wastewater separation method for reducing the volume of oil-containing scum is configured. In the oil-impregnated drainage separation method, (a) the oil-impregnated scum is stored in the storage tank, and (b) the vibrator is arranged in the storage tank so that the upper surface is inclined by a predetermined angle with respect to the liquid surface of the oil-impregnated scum. , (C) Supply high frequency power to the oscillator.

According to the present invention, fine bubbles can be generated in the oil-containing scum by the ultrasonic waves generated by the vibrator, and cavitation can be positively caused by the change in sound pressure. As a result, moisture (oil-containing drainage), dust, and the like can be effectively separated from the oil-containing scum by the impact pressure generated when the fine bubbles adhering to the oil-containing scum disappear (collapse). Since the upper surface of the oscillator is inclined at a predetermined angle with respect to the liquid surface of the oil-containing scum, the water (oil-containing drainage) separated from the oil-containing scum does not stay on the upper surface. That is, since the oil-impregnated scum can always be present on the upper surface of the oscillator, it is possible to promote the separation of water (oil-impregnated drainage) and dust from the oil-containing scum due to the cavitation effect. Further, since the upper surface of the oscillator is only tilted at a predetermined angle with respect to the liquid surface of the oil-containing scum, moisture (oil-containing drainage) and dust can be separated from the oil-containing scum with a space-saving and simple structure.

According to a further embodiment of the oil-impregnated wastewater separation method according to the present invention, in step (b), the vibrator is set so that the upper surface has an inclination angle of 15 degrees or more and 25 degrees or less, preferably about 20 degrees with respect to the liquid surface. Includes the step of placing the in a reservoir.

As a result of diligent research, the present inventor has found that the reduction rate of oil-containing scum becomes high when the inclination angle of the upper surface of the oscillator with respect to the liquid surface is 15 degrees or more and 25 degrees or less, preferably about 20 degrees. Here, the reduction rate is obtained by subtracting "the volume of the oil-containing scum after the volume reduction (after the treatment) in the storage tank" from "the volume of the oil-containing scum before the volume reduction (before the treatment) in the storage tank". The value is defined as a value multiplied by 100 after dividing by "volume of oil-containing scum before volume reduction (before treatment) in the storage tank". Based on the results of this research, in this embodiment, the inclination angle of the upper surface of the vibrator with respect to the liquid surface is set to 15 degrees or more and 25 degrees or less, preferably about 20 degrees. Thereby, the volume reduction of the oil-containing scum can be further promoted.

According to a further embodiment of the oil-impregnated wastewater separation method according to the present invention, in step (b), the oscillator is stored so that the distance between the portion of the upper surface closest to the liquid surface and the liquid surface is 5 cm or more. Includes steps to place in the tank.

As a result of diligent research, the present inventor, as a result of diligent research, when the distance between the upper surface of the oscillator and the liquid surface of the oil-containing scum is narrow, the vibration of the liquid surface of the oil-containing scum becomes intense, and the oil-containing scum separated by the effect of ultrasonic waves is produced. We have found that a phenomenon such as instant remixing occurs. Based on the results of this research, in this embodiment, the distance between the upper surface of the oscillator and the liquid level of the oil-containing scum is set to 5 cm or more. As a result, it is possible to suppress the reduction of the volume reduction effect of the oil-containing scum.

According to a further embodiment of the oil-impregnated wastewater separation method according to the present invention, step (b) is a step of arranging the vibrator in the storage tank in such a manner that a space is provided between the vibrator and the bottom surface of the storage tank. Includes.

According to this embodiment, the water (oil-impregnated drainage) separated from the oil-containing scum flows into the space between the vibrator and the bottom surface, and the oil-containing scum can be moved to the upper surface side of the vibrator by the convection effect. Further, it is possible to satisfactorily prevent the oscillator from being buried in the water (oil-impregnated drainage) separated from the oil-containing scum. This makes it possible to further promote the separation of water (oil-impregnated drainage) and dust from the oil-impregnated scum due to the cavitation effect.

According to the present invention, when separating the oil-containing wastewater from the oil-containing scum, it is possible to improve the treatment efficiency and save space at the same time.

It is a block diagram which shows the outline of the structure of the oil-impregnated drainage separation device 1 which concerns on embodiment of this invention. It is explanatory drawing which showed the experimental result about the relationship between the amount of oil-containing scum school, the reduction rate of oil-containing scum school, and the amount of oil in oil-containing drainage school (separated water). It is explanatory drawing which showed the experimental result about the relationship between the ultrasonic frequency and reduction rate output to the oil-impregnated scum school. It is explanatory drawing which showed the experimental result about the relationship between the output of an ultrasonic oscillator 8 and the reduction rate. It is explanatory drawing which showed the experimental result about the relationship between the inclination angle of the upper surface 4a of the ultrasonic vibrator 4 with respect to the liquid surface of oil-containing scum school, and the rate of change. It is a block diagram which shows the outline of the structure of the oil-impregnated drainage separation device 1A of a modification. It is a block diagram which shows the outline of the structure of the oil-impregnated drainage separation device 1B of a modification.

Next, the best mode for carrying out the present invention will be described with reference to examples.

As shown in FIG. 1, the oil-impregnated drainage separation device 1 according to the present embodiment includes a storage tank 2 capable of storing oil-containing scum, an ultrasonic vibrator 4 arranged in the storage tank 2, and the ultrasonic wave. The mounting table 6 arranged in the storage tank 2 so that the vibrator 4 can be mounted and the ultrasonic vibrator 4 can be electrically connected to the ultrasonic vibrator 4 via the power line L so that high-frequency power can be supplied. It is provided with the ultrasonic oscillator 8 and the temperature controller 30 for controlling the temperature of the oil-containing scum in the storage tank 2.

As shown in FIG. 1, the storage tank 2 has a tapered bottom wall 2a. In other words, it can be said that the bottom wall 2a has a shape that becomes deeper toward the center. A discharge pipe 10 with a valve is connected to about the center of the bottom wall 2a. That is, the discharge pipe 10 with a valve is connected to the deepest part of the storage tank 2. Further, a discharge pipe 12 with a valve is connected to the side wall 2b of the storage tank 2. The discharge pipe 12 with a valve is arranged at a position closer to the bottom wall 2a in the side wall 2b, preferably adjacent to the bottom wall 2a. An oil-containing scum school pumped from the oil-water separation tank 90 by the pump P is supplied to the storage tank 2 via the hose H. The oil-water separation tank 90 is a device that separates waste liquid and wastewater generated in a metal processing factory into floating oil foil, oil-containing scum school, oil-containing drainage Woil, and sludge slg.

The ultrasonic vibrator 4 is made of, for example, piezoelectric ceramics, and has a property of expanding and contracting by applying an AC voltage. That is, the ultrasonic transducer 4 converts electrical energy into mechanical energy, more specifically, converts high frequency power supplied from the ultrasonic oscillator 8 into mechanical vibration to generate ultrasonic waves. In the present embodiment, as the ultrasonic vibrator 4, an immersion type vibrator that is submerged in the storage tank 2 is used. The ultrasonic transducer 4 has a rectangular parallelepiped shape.

As shown in FIG. 1, the mounting table 6 is configured as a grid-like table having a predetermined height, and can be installed in the storage tank 2 by hooking it on the upper edge of the storage tank 2. .. Further, the mounting table 6 has a mounting surface 6a on which the ultrasonic vibrator 4 can be mounted. The mounting surface 6a has an inclination angle of about 20 degrees with respect to the liquid surface of the oil-containing scum Scoil stored in the storage tank 2. By mounting the ultrasonic vibrator 4 on the mounting surface 6a, the upper surface 4a of the ultrasonic vibrator 4 also has an inclination angle of about 20 degrees with respect to the liquid surface of the oil-containing scum school stored in the storage tank 2. Have. The height of the mounting table 6 is the portion of the upper surface 4a of the ultrasonic transducer 4 mounted on the mounting surface 6a that is closest to the liquid level of the oil-containing scum school, and the liquid level of the oil-containing scum school. The distance is set to be 5 cm or more. Since the ultrasonic vibrator 4 is mounted on the mounting surface 6a of the mounting table 6, a predetermined space R is formed between the ultrasonic vibrator 4 and the bottom wall 2a of the storage tank 2. .. In the present embodiment, the mounting table 6 is a grid-like table, but the upper surface 4a of the ultrasonic vibrator 4 has an inclination angle with respect to the liquid level of the oil-containing scum Scoil stored in the storage tank 2. Needless to say, any structure may be used as long as the ultrasonic vibrator 4 can be placed in the state.

The temperature controller 30 includes a heater (not shown), a switch (not shown) capable of intermittently energizing the heater, and a temperature sensor (not shown) for measuring the temperature of the oil-impregnated scum Scoil stored in the storage tank 2. It has a control device (not shown) that controls the switch based on the temperature measured by the temperature sensor. The control device compares the measured temperature with the temperature of the oil-impregnated scum Scoil stored in the storage tank 2 and controls the switch so that the temperature of the oil-impregnated scum Scoil maintains a desired temperature.

Next, the operation of the oil-impregnated wastewater separation device 1 according to the embodiment of the present invention thus configured will be described. First, in a state where the mounting table 6 and the ultrasonic transducer 4 are arranged in the storage tank 2, the oil-containing scum Scoil is stored in the storage tank from the oil-water separation tank 90 until the amount of the oil-containing scum Scoil in the storage tank 2 becomes about 30 L. Supply within 2. At this time, the upper surface 4a of the ultrasonic transducer 4 has an inclination angle of about 20 degrees with respect to the liquid surface of the oil-containing scum school. Further, the distance between the portion of the upper surface of the ultrasonic transducer 4 closest to the liquid level of the oil-containing scum school and the liquid level of the oil-containing scum school is set to be 5 cm or more. Further, a predetermined space R is formed between the ultrasonic vibrator 4 and the bottom wall 2a of the storage tank 2.

Subsequently, the temperature of the oil-containing scum school is set to 10 ° C. or higher and 40 ° C. or lower by the temperature controller 30, and high-frequency power is supplied from the ultrasonic oscillator 8 to the ultrasonic oscillator 4 in this state. Here, in the present embodiment, the high frequency power supplied from the ultrasonic oscillator 8 to the ultrasonic oscillator 4 is set to an output of 600 W (that is, the ultrasonic oscillator 8 has a high frequency power of 20 W per 1 L of oil-containing scum Scoil. The configuration is such that the ultrasonic frequency output to the oil-impregnated scum Scoil is set to 40 kHz.

When ultrasonic vibration is applied to the oil-containing scum school in the storage tank 2 in this way, the oil-impregnated drainage Wheel (separated water) is separated from the oil-containing scum school, and the oil-containing scum school having a relatively low specific density moves above the storage tank 2 and at the same time. The oil-impregnated wastewater (separated water) having a relatively large specific gravity moves to the lower side (bottom) of the storage tank 2. Here, the separation of the oil-impregnated wastewater (separated water) from the oil-impregnated scum School is performed by the following mechanism. That is, by applying ultrasonic vibration to the oil-containing scum school, fine bubbles can be generated in the oil-containing scum school and cavitation can be positively caused by the change in sound pressure, whereby the fine bubbles attached to the oil-containing scum school can be positively cavitated. The impact pressure generated when the school disappears (collapses) effectively separates the oil-impregnated drainage school (separated water) and dust from the oil-containing scum school.

Since the upper surface 4a of the ultrasonic transducer 4 has an inclination angle of 20 degrees with respect to the liquid surface of the oil-containing scum school, the oil-containing drainage wall (separated water) separated from the oil-containing scum school is the upper surface 4a. Never stay in. That is, the oil-containing scum school can always be present on the upper surface 4a of the ultrasonic transducer 4. Further, the oil-impregnated drainage Woil (separated water) flowing down the upper surface 4a flows into the space R between the ultrasonic vibrator 4 and the bottom wall 2a of the storage tank 2, and exists in the space R due to the convection effect. The oil-impregnated scum Scoil can be moved above the storage tank 2. Further, since the ultrasonic vibrator 4 is raised by the mounting table, it is possible to satisfactorily prevent the ultrasonic vibrator 4 from being buried in the oil-containing drainage wall (separated water) separated from the oil-containing scum school. This makes it possible to promote the separation of oil-impregnated drainage Woil (separated water) and dust from the oil-impregnated scum School due to the cavitation effect.

Since the distance between the portion of the upper surface of the ultrasonic transducer 4 closest to the liquid level of the oil-containing scum Scoil and the liquid level of the oil-containing scum Scoil is set to be 5 cm or more, the oil-containing scum Scoil is set. It is possible to prevent the occurrence of violent vibration near the liquid level. As a result, it is possible to suppress the reduction of the volume reducing effect of the oil-containing scum school.

Further, the amount of the oil-containing scum school is set to 30 L, the oil temperature of the oil-containing scum school is set to 10 ° C. or higher and 40 ° C. or lower, and the ultrasonic frequency output to the oil-containing scum school is set to 40 kHz. Since the output of the ultrasonic oscillator 8 is 600 W, it is possible to more effectively promote the oil-containing drainage (separated water) and the separation of dust from the oil-containing scum school.

After separating the oil-impregnated drainage Wheel (separated water) from the oil-impregnated scum School in the storage tank 2 in this way, the oil-containing drainage (separated water) can be discharged by opening the discharge pipe 10 with a valve. By opening the discharge pipe 12 with a valve, the volume-reduced oil-containing scum school can be discharged.

FIG. 2 is an explanatory diagram showing the experimental results regarding the relationship between the amount of oil-containing scum spill, the reduction rate of oil-containing scum spill, and the amount of oil in the oil-containing drainage wall (separated water), and FIG. 3 is an explanatory diagram. It is explanatory drawing which showed the experimental result about the relationship between the ultrasonic frequency and reduction rate output to the oil-impregnated scum Scoil, and FIG. 4 shows the experimental result about the relationship between the output and reduction rate of an ultrasonic oscillator 8. FIG. 5 is an explanatory diagram showing the experimental results regarding the relationship between the tilt angle and the rate of change of the upper surface 4a of the ultrasonic transducer 4 with respect to the liquid surface of the oil-containing scum Scoil.

As shown in FIG. 2, the relationship between the amount of oil-containing scum Scoil and the reduction rate of oil-containing scum Scoil shows that the reduction rate tends to decrease as the amount of oil-containing scum Scoil increases. Here, the reduction rate is defined as the volume reduction rate due to the removal of the oil-impregnated wastewater Wheel (separated water) from the oil-impregnated scum School. Specifically, "Before volume reduction (treatment in the storage tank 2)". The value obtained by subtracting the "volume of the oil-impregnated scum after volume reduction (after treatment) in the storage tank 2" from the "volume of the oil-impregnated scum in the previous)" is the value obtained by subtracting the "volume before volume reduction (before treatment) in the storage tank 2". It is defined as a value multiplied by 100 after dividing by "volume of scum". Here, the amount of oil in the oil-impregnated wastewater (separated water) (normal hexane extract substance amount, hereinafter referred to as "n-Hex". The unit is <mg / L>). It indicates that a lot of oil is dissolved in the separated water), which means that the water quality deteriorates. When the amount of oil-containing scum school was 45 L, both the reduction rate and n-Hex showed the smallest values, but the result was that the treatment effect was unstable and the treatment time was long. From the above results, in the present embodiment, the amount of oil-containing scum school was set to 20 L or more and 30 L or less, preferably 30 L.

As shown in FIG. 3, the relationship between the ultrasonic frequency output to the oil-containing scum school and the reduction rate showed the highest reduction rate in the vicinity of 40 kHz. From the above results, in the present embodiment, the ultrasonic frequency output to the oil-containing scum school is set to 20 kHz or more and 100 kHz or less, preferably about 40 kHz.

As shown in FIG. 4, the relationship between the output of the ultrasonic oscillator 8 and the reduction rate shows the largest reduction rate when the output is 600 W. If the output is larger than 600 W, the water quality of the separated oil-impregnated wastewater (separated water) deteriorates, and if the output is less than 400 W, the treatment time becomes long. From the above results, in the present embodiment, the output of the ultrasonic oscillator 8 is 400 W or more and 600 W or less, preferably 600 W. That is, the ultrasonic oscillator 8 is configured to supply high frequency power of 20 W or more and 30 W or less, preferably 20 W, to the ultrasonic oscillator 4 per 1 L of oil-impregnated scoil. When the ultrasonic frequency output to the oil-containing scum school was set to 40 kHz and the output of the ultrasonic oscillator 8 was set to 600 W, the reduction rate was 39% on average.

As shown in FIG. 5, the relationship between the tilt angle of the upper surface 4a of the ultrasonic transducer 4 and the rate of change with respect to the liquid surface of the oil-containing scum school shows the value with the largest rate of change when the tilt angle is about 17.5 degrees. The result was. Here, the rate of change is defined as the rate of increase / decrease in the reduction rate when the inclination angle of the upper surface 4a of the ultrasonic transducer 4 with respect to the liquid surface of the oil-impregnated scum School is 0 degree. From the above results, in the present embodiment, the inclination angle of the upper surface 4a of the ultrasonic vibrator 4 with respect to the liquid surface of the oil-containing scum school is set to 15 degrees or more and 25 degrees or less, preferably about 20 degrees.

According to the oil-impregnated drainage separation device 1 of the present invention according to the above-described embodiment, the upper surface 4a of the ultrasonic vibrator 4 has an inclination angle of 20 degrees with respect to the liquid surface of the oil-containing scum school. Since the ultrasonic vibrator 4 is only installed in the storage tank 2, the oil-containing drainage wall (separated water) and dust can be separated from the oil-containing scum school with a space-saving and simple structure. Moreover, since the upper surface 4a is inclined with respect to the liquid surface of the oil-containing scum school, the oil-containing drainage wall (separated water) separated from the oil-containing scum school does not stay on the upper surface 4a. That is, since the oil-impregnated scum school is always present on the upper surface 4a of the ultrasonic transducer 4, it is possible to promote the separation of the oil-containing drainage Woil (separated water) and dust from the oil-containing scum school due to the cavitation effect. .. As a result, the volume of the oil-containing scum school can be reduced at low cost, and the amount of industrial waste discharged can be reduced, which can contribute to the reduction of the industrial waste treatment cost.

Further, according to the oil-impregnated drainage separation device 1 of the present invention according to the present embodiment, since the space R exists between the ultrasonic vibrator 4 and the bottom wall 2a of the storage tank 2, the upper surface 4a flows down. The oil-impregnated drainage wall (separated water) flows into the space R, and the oil-containing scum school staying in the space R can be moved above the storage tank 2 due to the convection effect. This makes it possible to promote the separation of oil-impregnated drainage Woil (separated water) and dust from the oil-impregnated scum School due to the cavitation effect.

Further, according to the oil-impregnated drainage separation device 1 of the present invention according to the present embodiment, the portion of the upper surface of the ultrasonic transducer 4 closest to the liquid level of the oil-containing scum school, the liquid level of the oil-containing scum school, and the liquid level of the oil-containing scum school. Since the distance is set to be 5 cm or more, it is possible to prevent violent vibration from occurring on the liquid surface of the oil-containing scum school. As a result, it is possible to suppress the reduction of the volume reducing effect of the oil-containing scum school.

Further, according to the oil-containing drainage separation device 1 of the present invention according to the present embodiment, the amount of the oil-containing scum school is set to 30 L, the temperature of the oil-containing scum school is set to 10 ° C. or higher and 40 ° C. or lower, and further. Since the ultrasonic frequency output to the oil-containing scum school is set to 40 kHz and the output of the ultrasonic oscillator 8 is 600 W, the viscosity of the oil-containing scum school increases, so that the oil-containing scum school can be treated after volume reduction. Inconveniences such as difficulty, inconvenience that the oil-containing scum school and floating oil after volume reduction dissolve in the oil-containing drainage school due to the effect of ultrasonic waves, or the separation effect is reduced, or the separated oil-containing drainage (separated water) It is possible to suppress inconveniences such as deterioration of water quality. This makes it possible to more effectively separate the oil-impregnated wastewater (separated water) and dust from the oil-impregnated scum school.

In the present embodiment, the ultrasonic vibrator 4 is placed on the mounting surface 6a of the mounting table 6 so that the upper surface 4a is tilted by about 20 degrees with respect to the liquid surface of the oil-containing scum school and the ultrasonic vibrator is used. A space R is provided between the 4 and the bottom wall 2a of the storage tank 2, but the present invention is not limited to this. For example, as illustrated in the oil-impregnated drainage separation device 1A of the modified example shown in FIG. 6, by lifting one end of the ultrasonic vibrator 4, the upper surface 4a is tilted by about 20 degrees with respect to the liquid surface of the oil-containing scum Scoil. A space R may be provided between the ultrasonic vibrator 4 and the bottom wall 2a of the storage tank 2.

In the present embodiment, the upper surface 4a of the ultrasonic transducer 4 is tilted by about 20 degrees with respect to the liquid surface of the oil-containing scum school, but any tilt angle may be used as long as it is 15 degrees or more and 25 degrees or less.

In the present embodiment, 30 L of oil-containing scum school is stored in the storage tank 2, and the high-frequency power supplied from the ultrasonic oscillator 8 to the ultrasonic oscillator 4 is 600 W, but the present invention is not limited to this. For example, the storage tank 2 stores 20 L or more and 30 L or less of oil-impregnated scoil, and the ultrasonic oscillator 4 is supplied with high-frequency power of 400 W or more and 600 W or less. A configuration may be used in which high-frequency power of 20 W or more and 30 W or less is supplied to the ultrasonic vibrator 4.

In the present embodiment, the ultrasonic frequency output to the oil-impregnated scum School is 40 kHz, but any frequency may be used as long as it is 20 kHz or more and 100 kHz or less.

In the present embodiment, the upper surface 4a of the ultrasonic vibrator 4 is tilted with respect to the liquid surface of the oil-containing scum school, but the present invention is not limited to this. For example, as shown in the oil-impregnated drainage separation device 1B of the modified example illustrated in FIG. 7, the ultrasonic vibration is caused by the mounting table 6B without inclining the upper surface 4a of the ultrasonic transducer 4 with respect to the liquid surface of the oil-containing scum school. The child 4 may be placed in a raised state.

In the present embodiment, the oil-containing scum school is heated by a dedicated heater, but the present invention is not limited to this. Instead of the dedicated heater, the oil-containing scum school may be heated by the heat generated from a device arranged at a position where heat can be transferred to the oil-containing scum school, for example, the ultrasonic vibrator 4.

In the present embodiment, the temperature controller 30 includes a heater, a switch, a temperature sensor, and a control device, and controls the switch so that the temperature of the oil-containing scum school maintains a desired temperature. The configuration is limited to this. For example, the temperature controller 30 further includes a cooler and a second switch capable of interrupting the current that energizes the cooler, so that the temperature of the oil-containing scum school is maintained at a desired temperature. And it may be configured to control the second switch.

The present embodiment shows an example of the embodiment for carrying out the present invention. Therefore, the present invention is not limited to the configuration of the present embodiment.

1 Oil-impregnated drainage separator (oil-impregnated drainage separator)
1A Oil-impregnated drainage separator (oil-impregnated drainage separator)
1B Oil-impregnated drainage separator (oil-impregnated drainage separator)
2 Storage tank (storage tank)
2a Bottom wall (bottom)
2b Side wall 4 Ultrasonic oscillator (oscillator)
4a Top surface (top surface)
6 Mounting table 6B Mounting table 6a Mounting surface 8 Ultrasonic oscillator (oscillator)
10 Discharge pipe with valve 12 Discharge pipe with valve 90 Oil-water separation tank 30 Temperature controller (Temperature controller)
L Power line School Oil-impregnated scum (oil-impregnated scum)
H Hose P Pump Foil Floating Oil Wheel Oil-Containing Drainage Slg Sludge R Space

Claims (12)

An oil-impregnated wastewater separation device for reducing the volume of oil-impregnated scum.
A storage tank capable of storing the oil-impregnated scum and
An oscillator having an upper surface facing the liquid surface side of the oil-impregnated scum and being arranged in the storage tank with the upper surface tilted by a predetermined angle with respect to the liquid surface.
An oscillator electrically connected to the oscillator that can supply high frequency power to the oscillator,
An oil-impregnated drainage separator equipped with. The oil-impregnated wastewater separation device according to claim 1, wherein the upper surface has an inclination angle of 15 degrees or more and 25 degrees or less, preferably about 20 degrees with respect to the liquid surface. The oil-containing drainage according to claim 1 or 2, wherein the oscillator is arranged in the storage tank so that the distance between the portion of the upper surface closest to the liquid level and the liquid level is 5 cm or more. Separator. The storage tank has a bottom surface and has a bottom surface.
The oil-impregnated drainage separation device according to any one of claims 1 to 3, wherein the oscillator is arranged in the storage tank so as to have a space between the oscillator and the bottom surface. The oil-impregnated wastewater separation device according to any one of claims 1 to 4, wherein the ultrasonic frequency output to the oil-impregnated scum is 20 kHz or more and 100 kHz or less, preferably about 40 kHz. The oil-containing scum stored in the storage tank is 20 L or more and 30 L or less, preferably 30 L.
The oil-impregnated wastewater separation device according to any one of claims 1 to 5, wherein the high-frequency power is 400 W or more and 600 W or less, preferably 600 W. The oil-impregnated drainage separation device according to any one of claims 1 to 6, wherein the oscillator supplies the high-frequency power of 20 W or more and 30 W or less, preferably 20 W per 1 L of the oil-impregnated scum to the oscillator. The oil-impregnated wastewater separation device according to any one of claims 1 to 7, further comprising a temperature controller capable of adjusting the temperature of the oil-impregnated scum to 10 ° C. or higher and 40 ° C. or lower. It is an oil-impregnated wastewater separation method for reducing the volume of oil-impregnated scum.
(A) The oil-impregnated scum is stored in a storage tank, and the oil-impregnated scum is stored.
(B) The oscillator is arranged in the storage tank so that the upper surface is inclined by a predetermined angle with respect to the liquid level of the oil-impregnated scum.
(C) An oil-containing wastewater separation method for supplying high-frequency power to the oscillator. The step (b) includes a step of arranging the oscillator in the storage tank so that the upper surface has an inclination angle of 15 degrees or more and 25 degrees or less, preferably about 20 degrees with respect to the liquid surface. The oil-impregnated wastewater separation method according to claim 9. 9. The step (b) includes a step of arranging the oscillator in the storage tank so that the distance between the portion of the upper surface closest to the liquid level and the liquid level is 5 cm or more. Alternatively, the oil-impregnated wastewater separation method according to 10. 9. The oil-impregnated wastewater separation method according to item 1.

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