CN104003473B - The device of oil slick in waste water is removed based on ultrasonic liquid leveller and pressure transmitter - Google Patents

Abstract

The invention discloses a device for removing floating oil in waste water based on an ultrasonic liquid level meter and a pressure sensor, comprising: an oil-free water tank, an oil floating sand settling box, an inclined plate sedimentation area, a sand settling area, sewage distribution pipes, and oil floating oil receiving Tank, the first wireless pressure sensor, horizontal jet, the second wireless pressure sensor, oil slick area, wireless ultrasonic liquid level gauge, etc.; the use of wireless pressure sensor and wireless ultrasonic liquid level gauge reduces the cumbersome wiring and line faults in the project caused unreliability, while also reducing wiring costs. The present invention is also provided with a wireless ultrasonic liquid level gauge, through the synergistic effect of the wireless pressure sensor and the wireless ultrasonic liquid level gauge, it can be indirectly determined whether all the oil slick areas are oil slicks or part of them are oil slicks. When it is determined that all the oil slick areas are oil slicks, The oil slick layer floating above the water surface on the upper part of the oil slick settling box can be automatically removed. In addition, the structure of the present invention is more simple and concise, and it is convenient to manufacture and install.

Description

Device for removing floating oil in wastewater based on ultrasonic liquid level gauge and pressure sensor

technical field

The invention belongs to the technical field of oily wastewater treatment, and in particular relates to a device for removing floating oil in wastewater based on an ultrasonic liquid level gauge and a pressure sensor.

Background technique

Oily substances enter the water through different channels to form oily wastewater. Due to its large volume and wide area, and the characteristics of being difficult to treat, it becomes a kind of seriously harmful wastewater. Its sources mainly include: petroleum exploration and oil processing in the petroleum industry , extraction, storage and transportation; car washing in the transportation industry, oily wastewater discharged from oil washing tanks in railway locomotive depots; rolling water, lubricating oil and other wastewater mainly emulsified oil produced in the process of machinery manufacturing; in addition, the catering industry , textile industry, food processing industry and other manufacturing wastewater also contain a large amount of oily substances.

The existence forms of oil substances in water can be divided into four categories: slick oil, dispersed oil, emulsified oil and dissolved oil. The particle size of the oil droplet is generally 10-100 μm. The tiny particles suspended in the water are unstable. After standing for a period of time, oil slicks are often formed. The emulsified oil is formed due to the surfactant contained in the water. The particle size of the oil droplet is extremely large. Small, generally less than 10 μm, dissolved oil is an oil that is chemically dissolved in water, and its particle size can reach several nanometers.

At present, the treatment methods for slick oil, dispersed oil and emulsified oil (accounting for more than 90% of the total oil content) in oily wastewater are to try to make oil in different states float on the water surface, and then use oil scraping device, oil skimming device, Oil suction devices separate these oily substances from water, but these oil removal devices have at least some of the following disadvantages:

1. Oil and water cannot be strictly distinguished when removing oil slicks, especially when the oil content is small, it is easy to remove oil and water together, that is, a large amount of water is entrained in the process of removing oil slicks, so that the separated oil contains lots of moisture;

2. The device is relatively complicated, not easy to install underground, and the price is high;

3. Troublesome maintenance;

4. Inconvenient automation.

The main members of the invention group have applied for the following three invention patents with the same function: (1) "A method and device for automatically removing oil slicks and sand settling in oily wastewater" (authorized, invention number: ZL201210148765. 0), (2) "Method and device for removing oil slick and sand settling in wastewater based on special liquid level measuring instrument" (application number: 201210148784.3), (3) "Removing oil slick in wastewater based on the conductivity of oil and water and the method and device for sand settling" (authorized, invention number: ZL201210148783.9). The present invention is another new sister invention of the main members of the invention group based on different principles on the basis of the above three inventions. However, the existing device has cumbersome wiring in engineering and unreliability caused by line faults, and at the same time, the wiring cost is relatively high.

Contents of the invention

The purpose of the embodiment of the present invention is to provide a device for removing floating oil in wastewater based on an ultrasonic liquid level gauge and a pressure sensor, aiming to solve the unreliability caused by cumbersome wiring and line failures in existing oily wastewater treatment devices Sexuality, and the problem of high wiring costs at the same time.

The embodiment of the present invention is achieved in this way, a device for removing oil slicks in wastewater based on an ultrasonic liquid level gauge and a pressure sensor, the device for removing oil slicks in wastewater based on an ultrasonic liquid level gauge and a pressure sensor includes:

Oil-free water tank, aeration head, water collection pipe, oil slick sand settling box, inclined plate sedimentation area, sand settling area, mud discharge pipe, sewage distribution pipe, oil slick receiving box, first wireless pressure sensor, suction pipe, first Solenoid valve, drain pipe, second solenoid valve, transverse ejector, second wireless pressure sensor, oil slick area, liquid level line at the upper end of oil slick area, wireless ultrasonic liquid level gauge, water inlet pipe, third solenoid valve, fourth electromagnetic Valve, oil discharge pipe, oil suction pipe, sealing cover, flow meter, fifth solenoid valve, third wireless pressure sensor;

The aeration heads are respectively set at the bottom of the oil-free water tank and the upper part of the sand settling area of the oil-swimming settling box, and are respectively at the upper middle position of the bottom of the oil-free water tank and the bottom of the oil-swimming settling box; the first wireless pressure sensor is set at On the left side of the bottom of the oil-free water tank, the suction pipe is arranged on the left side of the oil-free water tank, and the first solenoid valve is installed on the suction pipe;

The oil slick settling box is set on the right side of the oil-free water tank, the inclined plate sedimentation area of the oil slick settling box is set in the middle of the oil slick settling box, and the sand settling area of the oil slick settling box is set At the bottom of the tank, the mud discharge pipe is set in the middle of the bottom of the sand settling area of the oil floating sand settling box, the water collecting pipe is set under the left side of the inclined plate sedimentation area of the oil floating sand settling box, and the water collecting pipe is connected to the oil-free water tank The drain pipe on the partition between the oil slick and sand settling box, the second solenoid valve is set on the drain pipe, and the horizontal jets are arranged in arrays opposite to each other above the left and right sides of the inclined plate sedimentation area of the oil slick and sand settling box. The oil slick area of the oil slick settling box is set above the oil slick settling box, the upper liquid level line of the oil slick area is set at the top of the oil slick area of the oil slick settling box, and the wireless ultrasonic liquid level gauge is set On the top of the sand box, the second wireless pressure sensor is set under the left side of the oil slick area of the oil slick settling box, the water inlet pipe is set on the right side of the oil slick settling box, the third solenoid valve is set on the water inlet pipe, and the sewage The water distribution pipe is connected to the water inlet pipe;

The oil slick receiving box is installed on the right side of the oil slick sand settling box, the third wireless pressure sensor is installed on the right side of the bottom of the oil slick receiving box, the oil suction pipe is installed on the right side of the oil slick receiving box, and the fifth solenoid valve is installed on the pumping On the oil pipe, the flow meter is installed below the fifth solenoid valve, the sealing cover is installed on the top of the oil slick receiving box, and the oil discharge pipe is installed on the partition between the oil slick sand settling box and the oil slick receiving box. The oil slick area of the sand box is connected, and the fourth electromagnetic valve is arranged on the oil discharge pipe.

Further, the specific method of judging the oil slick in the device based on the ultrasonic liquid level gauge and the pressure sensor to remove the slick oil in the wastewater is:

Firstly: the height from the bottom of the oil-free water tank to the lower part of the drain pipe is set to h ₁ , the thickness of the oil slick area is set to h ₂ , the height from the bottom of the oil slick receiving tank to the lower part of the oil drain pipe 100 mm is set to h ₃ , and in operation The pressures displayed by the first wireless pressure sensor, the second wireless pressure sensor, and the third wireless pressure sensor are respectively set to p ₁ , p ₂ , and p ₃ , the density of waste water is set to ρ _water , and the density of floating oil is set to ρ _oil ;

Secondly, when the oil slick settling box is in operation, when the highest liquid level reaches the position of the liquid level line at the upper end of the oil slick area, the pressure detected by the second wireless pressure sensor can vary depending on the thickness of the oil layer in the oil slick area. Divided into the following two situations:

1. p ₂ > _ρoil h ₂ , at this time the upper part of the oil slick area is the oil layer and the lower part is the waste water layer. When the oil content in the waste water is very small, especially when the operation starts, the upper part of the oil slick area may not be able to form a complete Oil slick, at this time the oil slick area is almost entirely wastewater, and when a complete oil slick is formed on the surface of the wastewater, the upper part of the oil slick is the waste oil layer and the lower part is the wastewater layer, that is, the thickness of the oil slick is less than h ₂ . If the thickness of the wastewater layer in the oil slick area is set as: δ, then the thickness of the oil slick layer is: (h ₂ -δ). Then, the pressure p2 detected by the _second wireless pressure sensor can be expressed by the following formula:

p ₂ = _ρwater δ+ _ρoil (h ₂ -δ)= _ρoil h ₂ +(ρwater _{- ρoil} )δ> _ρoil h ₂

So the pressure p ₂ detected by the second wireless pressure sensor > ρ _oil h ₂ ;

2. p ₂ = _ρoil h ₂ , at this time, the entire oil slick area is full of slick oil.

Further, the device for removing oil slicks in wastewater based on ultrasonic liquid level gauges and pressure sensors. The method for removing oil slicks and sand settling in oily wastewater includes the following steps:

Step 1, when the work starts, the central controller instructs to open the third solenoid valve (the two are connected through the control line), and at this time the other solenoid valves are all in the closed state, and the oily and sandy sewage to be treated flows into the The water inlet pipe or a pump is used to drive in, and then sent to the sewage distribution pipe through the water inlet pipe, and then the sewage distribution pipe distributes the sewage evenly in the longitudinal direction of the side of the middle and lower part of the sand settling area of the oil slick sand settling box, perpendicular to the direction of the paper;

Step 2, when the liquid level indicated by the wireless ultrasonic liquid level gauge reaches the position of the liquid level line at the upper end of the oil slick area, at the same time the second wireless pressure sensor indicates that the pressure p ₂ > _ρoil h ₂ , and the liquid level measured by the wireless ultrasonic liquid level gauge After the data and the pressure data measured by the second wireless pressure sensor are transmitted to the central controller through their respective data lines connected to the central controller, the central controller (pre-implanted program) instructs to open the second solenoid valve (between the two Connected through the control line), and at the same time close the third solenoid valve, the sewage enters and stops, and the sewage after the oil slick and sand settling enters the drain pipe through the water collection pipe and then flows into the oil-free water tank by itself; when the wireless ultrasonic level gauge indicates the oil slick and sand settling When the liquid level of the tank is consistent with the upper part of the sloping plate sedimentation area, the central controller instructs to close the second solenoid valve and open the third solenoid valve at the same time, and the sewage continues to flow into the oil floating sand settling tank;

Step 3, when the liquid level indicated by the wireless ultrasonic liquid level gauge reaches the position of the liquid level line at the upper end of the oil slick area, at the same time the second wireless pressure sensor indicates that the pressure p ₂ = _ρoil h ₂ , and the liquid level measured by the wireless ultrasonic liquid level gauge After the data and the pressure data measured by the second wireless pressure sensor are transmitted to the central controller through their respective data lines connected to the central controller, the central controller instructs to open the fourth solenoid valve (the two are connected through a control line) At the same time, close the third solenoid valve to stop the sewage from entering, and the floating oil flows into the floating oil receiving tank through the oil discharge pipe; when the wireless ultrasonic liquid level gauge indicates that the liquid level of the floating oil sand settling box is consistent with the upper part of the oil discharge pipe, close the fourth electromagnetic valve The valve opens the third solenoid valve at the same time, and the sewage continues to enter the oil floating sand settling box;

Step 4, when the first wireless pressure sensor indicates that the pressure of the oil-free water tank is: p ₁ =ρ _water h ₁ , and the data is transmitted to the central controller through the data line, the central controller instructs to open the first solenoid valve (two They are connected by control lines), and the sewage after degreasing and sanding is pumped into the next sewage treatment process through the suction pipe; when the first wireless pressure sensor indicates that the pressure of the oil-free water tank is less than a certain preset value ( This value is close to 0), and the central controller instructs to close the first solenoid valve;

Step five, when the third wireless pressure sensor indicates that the pressure of the floating oil receiving tank is p ₃ =ρ _oil h ₃ , the central controller instructs to open the fifth solenoid valve (the two are connected through a control line) to flow through the floating oil The meter and the oil suction pipe are pumped into the waste oil collection barrel, and at the same time, the flow meter transmits the amount of waste oil entering the waste oil collection barrel to the monitoring center through the wireless network; when the third wireless pressure sensor indicates that the pressure of the floating oil receiving tank When a certain value (this value is close to 0), the central controller instructs to close the fifth electromagnetic valve.

Further, a sealing cover is provided to prevent waste oil from being taken away without passing the flow meter.

Further, it is provided with an aeration head for preventing the water body of the oil-free water tank and the oil slick settling tank from becoming smelly.

Further, the lateral ejectors jet against each other in pairs to make the waste water in the middle of the degreasing grit chamber relatively flow, increasing the chance of collision between liquid particles.

Further, RISEN wireless ultrasonic liquid level gauge is adopted.

The device for removing floating oil in wastewater based on an ultrasonic liquid level gauge and a pressure sensor provided by the present invention uses a wireless pressure sensor, which reduces cumbersome wiring in engineering and unreliability caused by line failures, and also reduces wiring costs. The present invention is also provided with a wireless ultrasonic liquid level gauge, through the synergistic effect of the wireless pressure sensor and the wireless ultrasonic liquid level gauge, it can be indirectly determined whether all the oil slick areas are oil slicks or part of them are oil slicks. When it is determined that all the oil slick areas are oil slicks, The oil slick layer floating above the water surface on the upper part of the oil slick settling box can be automatically removed. In addition, the structure of the present invention is more simple and concise, and it is convenient to manufacture and install.

Description of drawings

Fig. 1 is a schematic structural diagram of a device for removing floating oil in wastewater based on an ultrasonic liquid level gauge and a pressure sensor provided by an embodiment of the present invention;

In the figure: 1. Oil-free water tank; 2. Aeration head; 3. Water collection pipe; 4. Oil floating sand settling box; 5. Inclined plate sedimentation area; 6. Sand settling area; 7. Mud discharge pipe; Water distribution pipe; 9. Slick oil receiving box; 10. First wireless pressure sensor; 11. Suction pipe; 12. First solenoid valve; 13. Drainage pipe; 14. Second solenoid valve; 15. Transverse ejector; 16. The second wireless pressure sensor; 17, the oil slick area; 18, the liquid level line at the upper end of the oil slick area; 19, the wireless ultrasonic liquid level gauge; 20, the water inlet pipe; 21, the third solenoid valve; 22, the fourth solenoid valve; 23 , oil discharge pipe; 24, oil suction pipe; 25, sealing cover; 26, fifth solenoid valve; 27, flow meter; 28, third wireless pressure sensor.

detailed description

In order to make the object, technical solution and advantages of the present invention more clear, the present invention will be further described in detail below in conjunction with the examples. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

The application principle of the present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

As shown in Figure 1, the device for removing floating oil in waste water based on ultrasonic liquid level gauge and pressure sensor according to the embodiment of the present invention mainly consists of:

Oil-free water tank 1, aeration head 2, water collection pipe 3, oil floating sand settling box 4, inclined plate sedimentation area 5, sand settling area 6, mud discharge pipe 7, sewage distribution pipe 8, floating oil receiving box 9, the first Wireless pressure sensor 10, suction pipe 11, first solenoid valve 12, drain pipe 13, second solenoid valve 14, lateral jet 15, second wireless pressure sensor 16, oil slick area 17, liquid level line 18 at the upper end of the oil slick area , wireless ultrasonic level meter 19, water inlet pipe 20, third solenoid valve 21, fourth solenoid valve 22, oil discharge pipe 23, oil extraction pipe 24, sealing cover 25, fifth solenoid valve 26, flow meter 27, third wireless pressure The sensor 28 is composed of;

The aeration head 2 is respectively arranged on the bottom of the oil-free water tank 1 and the upper part of the sand settling area 6 of the oil-slick sand settling box, and is respectively located in the middle position above the bottom of the oil-free water tank 1 and the bottom of the oil-slick sand settling box 4; The first wireless pressure sensor 10 is arranged on the left side of the bottom of the oil-free water tank 1, the suction pipe 11 is arranged on the left side of the oil-free water tank 1, and the first electromagnetic valve 12 is installed on the water suction pipe 11;

The oil slick settling box 4 is set on the right side of the oil-free water tank 1, the inclined plate sedimentation area 5 of the oil slick settling box is set at the middle position of the oil slick settling box 4, and the grit settling area 6 of the oil slick settling box is set At the bottom of the oil floating sand settling box 4, the mud discharge pipe 7 is arranged at the middle position at the bottom of the sand settling area 6 of the oil floating sand settling box, and the water collecting pipe 3 is arranged on the left side of the inclined plate sedimentation area 5 of the oil floating sand settling box Below, the water collecting pipe 3 is connected to the drain pipe 13 arranged on the partition between the oil-free water tank 1 and the oil floating sand settling box 4, the second electromagnetic valve 14 is arranged on the drain pipe 13, and the transverse jet 15 The left and right sides of the slant plate settling area are oppositely arranged in arrays, the oil slick area 17 of the oil slick settling box is set above the oil slick settling box 4, and the liquid level line 18 at the upper end of the oil slick area is set at the top of the oil slick settling box 4. On the top of the oil slick area 17 of the sand box, the wireless ultrasonic liquid level gauge 19 is arranged on the top of the oil slick and sand sink box 4, and the second wireless pressure sensor 16 is arranged on the left side of the oil slick area 17 of the oil slick sand box, The water inlet pipe 20 is arranged on the right side of the oil floating sand settling box 4, the third solenoid valve 21 is arranged on the water inlet pipe 20, and the sewage distribution pipe 8 is connected to the water inlet pipe 20;

The floating oil receiving box 9 is arranged on the right side of the floating oil receiving box 4, the third wireless pressure sensor 28 is installed on the right side at the bottom of the floating oil receiving box 9, and the oil suction pipe 24 is installed on the right side of the floating oil receiving box 9. The fifth electromagnetic valve 26 is installed on the oil suction pipe 24, the flowmeter 27 is installed below the fifth electromagnetic valve 26, the sealing cover 25 is installed on the top of the oil floating receiving box 9, and the oil discharge pipe 23 is installed on the oil floating sand settling box 4 and The separator in the middle of the oil floating receiving box 9 communicates with the oil floating area 17 of the oil floating sand settling box, and the fourth electromagnetic valve 22 is arranged on the oil discharge pipe 23 .

The working principle of the present invention is illustrated in conjunction with the structure:

1. When the work starts, the central controller instructs to open the third solenoid valve 21 (the two are connected through the control line), and at this time the other solenoid valves are all in the closed state, and the oily and sandy sewage to be treated flows into the Water inlet pipe 20 (or drive in with a pump), is sent to sewage distribution pipe 8 through water inlet pipe 20, and then sewage distribution pipe 8 is in the longitudinal direction (direction perpendicular to the paper surface) of one side of the middle and lower part of the sand settling area of the floating oil sand settling box. ) to distribute the sewage evenly.

2. When the liquid level indicated by the wireless ultrasonic liquid level gauge 19 reaches the position of the liquid level line 18 at the upper end of the oil slick area, at the same time the second wireless pressure sensor indicates that the pressure p ₂ > _ρoil h ₂ , and the liquid level measured by the wireless ultrasonic liquid level gauge After the bit data and the pressure data measured by the second wireless pressure sensor are transmitted to the central controller through their respective data lines connected to the central controller, the central controller (input into a programmed computer in advance) instructs to open the second solenoid valve 14 (the two are connected by control circuit), close the third electromagnetic valve 21 sewage simultaneously and stop, and the sewage after the oil slick and sand settling enters the drainpipe 13 by the water collecting pipe 3 and then flows into the oil-free water tank 1 automatically; When the ultrasonic liquid level meter 19 indicates that the liquid level of the oil floating sand settling box 4 is consistent with the upper part of the inclined plate sedimentation area 5, the central controller instructs to close the second solenoid valve 14 and open the third solenoid valve 21 at the same time, and the sewage continues to flow into the floating oil Grit box 4.

3. When the liquid level indicated by the wireless ultrasonic liquid level gauge 19 reaches the position of the liquid level line 18 at the upper end of the oil slick area, at the same time the second wireless pressure sensor indicates that the pressure p ₂ = _ρoil h ₂ , and the liquid level measured by the wireless ultrasonic liquid level gauge After the bit data and the pressure data measured by the second wireless pressure sensor are transmitted to the central controller through their respective data lines connected to the central controller, the central controller instructs to open the fourth electromagnetic valve 22 (between the two through the control circuit phase connection), close the third solenoid valve 21 and stop the sewage from entering at the same time, and the slick oil enters the slick oil receiving box 9 through the oil discharge pipe 23; When the upper part is consistent, close the fourth electromagnetic valve 22 and open the third electromagnetic valve 21 at the same time, and the sewage continues to enter the oil floating sand settling box 4 .

4. When the first wireless pressure sensor 10 indicates that the pressure of the oil-free water tank 1 is: p ₁ =ρ _water h ₁ , the central controller (input into a programmed computer in advance) instructs to open the first solenoid valve 12 (between the two are connected by control lines), and the sewage after degreasing and grit settling is pumped into the next sewage treatment process through the suction pipe 11. When the first wireless pressure sensor 10 indicated that the pressure of the oil-free water tank 1 was less than a certain preset value (this value was close to 0), the central controller (input into a programmed computer in advance) instructed to close the first electromagnetic valve 12.

5. When the third wireless pressure sensor 28 indicates that the pressure of the floating oil receiving tank 9 is p ₃ =ρ _oil h ₃ , the central controller (input into a programmed computer in advance) instructs to open the fifth electromagnetic valve 26 (between the two The floating oil is pumped into the waste oil collection barrel through the flow meter 27 and the oil suction pipe 24, and the flow meter 27 transmits the amount of waste oil entering the waste oil collection barrel to the monitoring center through the wireless network. In this way, the monitoring center can accurately grasp the quantity of waste oil produced in time, so that it can be allocated in time. If the device is applied to large hotels, restaurants and other eating places, the kitchen waste oil produced can be remotely controlled and managed, and then the raw materials of waste oil can be controlled from the source to ensure that ordinary people can eat safe oil. When the third wireless pressure sensor 28 indicates that the pressure of the floating oil receiving tank 9 is less than a certain preset value (this value is close to 0), the central controller (input into a programmed computer in advance) instructs to close the fifth solenoid valve 26 .

6. The sealing cover 25 is provided to prevent the waste oil from being taken away without the flow meter 27. Its effect is to ensure that the waste oil collected by the device is all measured by the flow meter 26 and then allocated under the monitoring of the monitoring center.

7. In order to prevent the water body from becoming stinky, a small underwater aeration head 2 is respectively arranged in the oil-free water tank and the oil floating sand settling box. In summer, the central controller (input into the programmed computer in advance) instructs the aeration head in the oil-free water tank and the oil floating sand settling box to aerate for 5-10 minutes every three days.

In addition, in order to increase the collision between the liquid particles, especially in the middle of the oil-removing grit chamber, several groups of relative transverse jets 15 are installed. The relative flow of waste water (including other complex flows that are difficult to describe simply) increases the collision between liquid particles, thus creating more particles for most of the dispersed oil and some emulsified oil with smaller particles to combine into larger particles. Then these oil particles will naturally float to the upper part of the liquid surface, thereby increasing the degreasing efficiency by about 3%. More importantly, the part of the oil that is removed more is dispersed oil and emulsified oil. Usually they are difficult to remove. When they enter the next process, they will bring great difficulties to the following process (because whether it is dispersed oil or emulsified oil are recalcitrant organics, they are very difficult to biodegrade).

The invention adopts the RISEN wireless ultrasonic liquid level gauge, which includes three parts: ultrasonic liquid level detection, wireless transceiver system, and receiving host. It is composed of ultrasonic liquid level gauge-power converter, encoder, modulation circuit, high-frequency amplifier circuit, frequency conversion circuit, demodulation circuit, decoder, level digital display and antenna. The signal of level measurement is coded and transmitted by radio wave, and it is decoded, received, counted and displayed at the receiving point. Its transmission and reception adopt short-wave frequency and coaxial ground network antenna, and the transmitted signal wave can be reflected and transmitted to the distant place through the high-altitude ionosphere, so as to achieve the purpose of long-distance measurement of material level.

Due to the wireless transmission adopted, the wireless ultrasonic liquid level gauge solves some problems such as difficult wiring, long distance, and high cost. , well water intake control, and water supply and drainage and other liquid supply and discharge for production in industries such as water supply, fire protection, light industry, printing and dyeing, chemical fiber, papermaking, chemical industry, food, beverage, brewing, sugar refining, breeding, industrial mining, agriculture, water treatment, etc. Automatic control or upper and lower limit liquid level alarm.

The present invention is based on ultrasonic liquid level instrument and pressure sensor to remove the device (as shown in Figure 1) of floating oil in waste water. In order to accurately grasp the variation of the thickness of the oil slick layer on the upper part of the oil slick settling box 4, the present invention especially sets a wireless pressure sensor at the lower end of the oil slick area of the oil slick settling box, and sets a wireless ultrasonic liquid level gauge at the upper part of the oil slick area . Through the synergistic effect of the wireless pressure sensor and the wireless ultrasonic liquid level gauge, it can be indirectly determined whether all the oil slick areas are oil slicks or part of them are oil slicks. And then when it is found that the oil slick area is all oil slick, the oil slick layer floating on the water surface can be automatically removed with the top of the oil slick sand box, the specific method is:

Firstly: the height from the bottom of the oil-free water tank to the lower part of the drain pipe is set to h ₁ , the thickness of the oil slick area is set to h ₂ , the height from the bottom of the oil slick receiving tank to the lower part of the oil drain pipe 100 mm is set to h ₃ , and in operation The pressures displayed by the first wireless pressure sensor, the second wireless pressure sensor, and the third wireless pressure sensor are respectively set to p ₁ , p ₂ , and p ₃ , the density of waste water is set to ρ _water , and the density of floating oil is set to ρ _oil .

When the oil slick settling tank is in operation, when the highest liquid level reaches the liquid level line at the upper end of the oil slick area, according to the thickness of the oil layer in the oil slick area, the pressure detected by the second wireless pressure sensor can be divided into: The following two situations:

1. p ₂ > _ρoil h ₂ , at this time the upper part of the oil slick area is the oil layer and the lower part is the waste water layer (when the oil content in the waste water is very small, especially when the device starts to operate, the upper part of the oil slick area may not be formed yet complete oil slick), then the oil slick area is almost entirely wastewater, and when a complete oil slick is formed on the surface of the wastewater, the upper part of the oil slick area is the waste oil layer and the lower part is the wastewater layer, that is, the thickness of the oil slick is less than h ₂ . If the thickness of the wastewater layer in the oil slick area is set as: δ, then the thickness of the oil slick layer is: (h ₂ -δ). Then, the pressure p2 detected by the _second wireless pressure sensor can be expressed by the following formula:

p ₂ = _ρwater δ+ _ρoil (h ₂ -δ)= _ρoil h ₂ +(ρwater _{- ρoil} )δ> _ρoil h ₂

So the pressure p ₂ detected by the second wireless pressure sensor > ρ _oil h ₂ ;

2. p ₂ = _ρoil h ₂ , at this time, the entire oil slick area is full of slick oil.

The device for removing floating oil in wastewater based on an ultrasonic liquid level gauge and a pressure sensor of the present invention is to automatically separate oil and sand from wastewater through the synergy of the wireless pressure sensor and the wireless ultrasonic liquid level gauge; the structure is simple, the operation is convenient, and the oil content is improved. Wastewater treatment efficiency.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the protection of the present invention. within range.

Claims (7)

1. A device based on ultrasonic liquid level meter and pressure sensor to remove oil slick in waste water, it is characterized in that, this device based on ultrasonic liquid level meter and pressure sensor to remove oil slick in waste water comprises: Oil-free water tank, aeration head, water collection pipe, oil slick sand settling box, inclined plate sedimentation area, sand settling area, mud discharge pipe, sewage distribution pipe, oil slick receiving box, first wireless pressure sensor, suction pipe, first Solenoid valve, drain pipe, second solenoid valve, transverse ejector, second wireless pressure sensor, oil slick area, liquid level line at the upper end of oil slick area, wireless ultrasonic liquid level gauge, water inlet pipe, third solenoid valve, fourth electromagnetic Valve, oil discharge pipe, oil suction pipe, sealing cover, flow meter, fifth solenoid valve, third wireless pressure sensor; The aeration heads are respectively set at the bottom of the oil-free water tank and the upper part of the sand settling area of the oil-swimming settling box, and are respectively at the upper middle position of the bottom of the oil-free water tank and the bottom of the oil-swimming settling box; the first wireless pressure sensor is set at On the left side of the bottom of the oil-free water tank, the suction pipe is arranged on the left side of the oil-free water tank, and the first solenoid valve is installed on the suction pipe; The oil slick settling box is set on the right side of the oil-free water tank, the inclined plate sedimentation area of the oil slick settling box is set in the middle of the oil slick settling box, and the sand settling area of the oil slick settling box is set At the bottom of the tank, the mud discharge pipe is set in the middle of the bottom of the sand settling area of the oil floating sand settling box, the water collecting pipe is set under the left side of the inclined plate sedimentation area of the oil floating sand settling box, and the water collecting pipe is connected to the oil-free water tank The drain pipe on the partition between the oil slick and sand settling box, the second solenoid valve is set on the drain pipe, and the horizontal jets are arranged in arrays opposite to each other above the left and right sides of the inclined plate sedimentation area of the oil slick and sand settling box. The oil slick area of the oil slick settling box is set above the oil slick settling box, the upper liquid level line of the oil slick area is set at the top of the oil slick area of the oil slick settling box, and the wireless ultrasonic liquid level gauge is set On the top of the sand box, the second wireless pressure sensor is set under the left side of the oil slick area of the oil slick settling box, the water inlet pipe is set on the right side of the oil slick settling box, the third solenoid valve is set on the water inlet pipe, and the sewage The water distribution pipe is connected to the water inlet pipe; The oil slick receiving box is installed on the right side of the oil slick sand settling box, the third wireless pressure sensor is installed on the right side of the bottom of the oil slick receiving box, the oil suction pipe is installed on the right side of the oil slick receiving box, and the fifth solenoid valve is installed on the pumping On the oil pipe, the flow meter is installed below the fifth solenoid valve, the sealing cover is installed on the top of the oil slick receiving box, and the oil discharge pipe is installed on the partition between the oil slick sand settling box and the oil slick receiving box. The oil slick area of the sand box is connected, and the fourth electromagnetic valve is arranged on the oil discharge pipe. 2. the device based on ultrasonic liquid level meter and pressure sensor to remove oil slick in waste water as claimed in claim 1, is characterized in that, this device judges oil slick layer thickness based on ultrasonic liquid level meter and pressure sensor to remove oil slick in waste water The specific method is: First, set the height from the bottom of the oil-free water tank to the lower part of the drain pipe as h ₁ , the thickness of the oil slick area as h ₂ , and the height from the bottom of the oil slick receiving tank to the lower 100mm of the oil drain pipe as h ₃ , during operation The pressures displayed by the first wireless pressure sensor, the second wireless pressure sensor, and the third wireless pressure sensor are p ₁ , p ₂ , and p ₃ respectively, the density of waste water is ρ _water , and the density of slick oil is ρ _oil ; Secondly, when the oil slick settling box is in operation, when the highest liquid level reaches the position of the liquid level line at the upper end of the oil slick area, the pressure detected by the second wireless pressure sensor can vary depending on the thickness of the oil layer in the oil slick area. Divided into the following two situations: When p ₂ > _ρoil h ₂ , the upper part of the oil slick area is the oil layer and the lower part is the wastewater layer. When the oil content in the wastewater is very small, especially when the operation starts, the upper part of the oil slick area may not be able to form a complete oil slick layer , then the oil slick area is almost entirely waste water layer, and when a complete oil slick layer is formed on the wastewater surface, the upper part of the oil slick area is the waste oil layer and the lower part is the waste water layer, that is, when p ₂ > _ρoil h ₂ , the thickness of the oil slick layer is less than h ₂ ; if the thickness of the wastewater layer in the oil slick area is set to be: δ, then the thickness of the oil slick layer is: (h ₂ -δ), then, at this moment, the pressure p ₂ detected by the second wireless pressure sensor can be used in the following formula express: p ₂ = _ρwater δ+ _ρoil (h ₂ -δ)= _ρoil h ₂ +(ρwater _{- ρoil} )δ> _ρoil h ₂ So the pressure p ₂ detected by the second wireless pressure sensor > ρ _oil h ₂ ; When p ₂ =ρoil h ₂ , the entire _oil slick area is full of slick oil. 3. as claimed in claim 1 or 2, based on ultrasonic liquid level meter and pressure sensor to remove the device of oil slick in waste water, it is characterized in that, this device based on ultrasonic liquid level meter and pressure sensor to remove oil slick in waste water removes oily waste water The method for oil slick and sand settling includes the following steps: Step 1. When the work starts, the central controller instructs to open the third solenoid valve. At this time, the other solenoid valves are all closed. The oily and sandy sewage to be treated flows into the water inlet pipe from the ground or pumped in, and passes through the water inlet pipe. Send it to the sewage distribution pipe, and then the sewage distribution pipe distributes the sewage evenly in the longitudinal direction of the side of the middle and lower part of the sand settling area of the oil slick sand settling box, and in the direction perpendicular to the paper surface; Step 2, when the liquid level indicated by the wireless ultrasonic liquid level gauge reaches the position of the liquid level line at the upper end of the oil slick area, at the same time the second wireless pressure sensor indicates that the pressure p ₂ > _ρoil h ₂ , and the measured value indicated by the wireless ultrasonic liquid level gauge After the liquid level data and the pressure data measured by the second wireless pressure sensor are transmitted to the central controller through their respective data lines connected to the central controller, the central controller instructs to open the second solenoid valve and close the third solenoid valve at the same time. Stop, the sewage after the oil slick and sand settling enters the drain pipe through the water collecting pipe and then flows into the oil-free water tank by itself; The controller instructs to close the second solenoid valve and open the third solenoid valve at the same time, and the sewage continues to flow into the oil floating sand settling box; Step 3, when the liquid level indicated by the wireless ultrasonic liquid level gauge reaches the position of the liquid level line at the upper end of the oil slick area, at the same time the second wireless pressure sensor indicates the pressure p ₂ = _ρoil h ₂ , and the measured pressure indicated by the wireless ultrasonic liquid level gauge After the liquid level data and the pressure data measured by the second wireless pressure sensor are transmitted to the central controller through their respective data lines connected to the central controller, the central controller instructs to open the fourth solenoid valve and close the third solenoid valve at the same time to stop the sewage Enter, the slick oil flows into the oil slick receiving tank through the oil discharge pipe; when the wireless ultrasonic liquid level gauge indicates that the liquid level of the oil slick sandbox is consistent with the upper part of the oil discharge pipe, close the fourth solenoid valve and open the third solenoid valve at the same time, the sewage Continue to enter the oil floating sand settling box; Step 4, when the first wireless pressure sensor indicates that the pressure of the oil-free water tank is: p ₁ =ρ _water h ₁ , and the data is transmitted to the central controller through the data line, the central controller instructs to open the first electromagnetic valve, except The sewage after oil-settling is pumped into the next sewage treatment process through the suction pipe; when the first wireless pressure sensor indicates that the pressure of the oil-free water tank is lower than a certain preset value, the central controller instructs to close the first solenoid valve; Step five, when the third wireless pressure sensor indicates that the pressure of the floating oil receiving tank is p ₃ =ρ _oil h ₃ , the central controller instructs to open the fifth solenoid valve and the floating oil is pumped into the waste oil collection barrel through the flow meter and the oil suction pipe, At the same time, the flow meter transmits the amount of waste oil entering the waste oil collection barrel to the monitoring center through the wireless network; when the third wireless pressure sensor indicates that the pressure in the floating oil receiving tank is less than a preset value, the central controller instructs to close the first Five solenoid valves. 4. The device for removing floating oil in waste water based on ultrasonic liquid level meter and pressure sensor as claimed in claim 1, characterized in that, it is set as a sealing cover that prevents waste oil from being taken away without passing through the flowmeter. 5. The device for removing oil slick in waste water based on ultrasonic liquid level meter and pressure sensor as claimed in claim 1, is characterized in that, the aeration head that prevents oil-free water tank and oil slick sand settling box water body from getting smelly is set. 6. The device for removing floating oil in waste water based on ultrasonic liquid level meter and pressure sensor as claimed in claim 1, is characterized in that, horizontal jets make the waste water in the middle part of the degreasing sand chamber flow relatively in two opposite jets in the transverse direction, Increase the chance of collision between liquid particles, speed up the floating of waste oil, and also increase the proportion of floating waste oil. 7. The device for removing floating oil in waste water based on ultrasonic liquid level gauge and pressure sensor as claimed in claim 1, characterized in that RISEN wireless ultrasonic liquid level gauge is used.