CN114538552A - Rotational flow air flotation control method and rotational flow air flotation equipment - Google Patents
Rotational flow air flotation control method and rotational flow air flotation equipment Download PDFInfo
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- CN114538552A CN114538552A CN202210254320.4A CN202210254320A CN114538552A CN 114538552 A CN114538552 A CN 114538552A CN 202210254320 A CN202210254320 A CN 202210254320A CN 114538552 A CN114538552 A CN 114538552A
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- liquid level
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- oil spilling
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/24—Treatment of water, waste water, or sewage by flotation
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/008—Control or steering systems not provided for elsewhere in subclass C02F
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/40—Devices for separating or removing fatty or oily substances or similar floating material
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- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
- G05D9/00—Level control, e.g. controlling quantity of material stored in vessel
- G05D9/12—Level control, e.g. controlling quantity of material stored in vessel characterised by the use of electric means
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2209/00—Controlling or monitoring parameters in water treatment
- C02F2209/42—Liquid level
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Abstract
The invention discloses a rotational flow air flotation control method, which comprises the following steps: periodically collecting the oil level in the oil spilling cylinder, and calculating the average liquid level in the current unit time; comparing the average liquid level with the lowest liquid level of the oil spilling cylinder and the highest liquid level of the oil spilling cylinder, and adjusting the average liquid level with the lowest liquid level of the oil spilling cylinder and the highest liquid level of the oil spilling cylinder according to the comparison result as follows: when the average liquid level is lower than the lowest liquid level of the oil spilling cylinder, the liquid level of the tank body is controlled to rise until the average liquid level reaches a position between the lowest liquid level of the oil spilling cylinder and the highest liquid level of the oil spilling cylinder; when the average liquid level is higher than the highest liquid level of the oil spilling cylinder, the liquid level of the tank body is controlled to descend until the average liquid level reaches a position between the lowest liquid level of the oil spilling cylinder and the highest liquid level of the oil spilling cylinder; and when the average liquid level is between the lowest liquid level of the oil spilling cylinder and the highest liquid level of the oil spilling cylinder, the liquid level of the tank body is kept unchanged. The rotational flow air flotation control method can adapt to oil discharge and slag removal operation under different working conditions, and ensures the optimal oil discharge and slag removal effect.
Description
Technical Field
The invention relates to the field of petrochemical industry, in particular to a rotational flow air flotation control method and rotational flow air flotation equipment.
Background
In the water treatment process in the petroleum and petrochemical field, an air floatation device is needed to separate oil drops or smaller suspended matters in water by utilizing micro bubbles, so that the water purification effect is achieved.
The cyclone air flotation device is a commonly used separation device, and mainly utilizes the cyclone effect to increase the adhesion frequency of microbubbles and impurities in water, so that the particle size of the impurities is increased, the density is reduced, and the impurities are easier to separate. Meanwhile, the centripetal force generated by the rotational flow enables the impurities and the bubble adhesive to be close to the middle, thereby being beneficial to the separation of the impurities.
The existing rotational flow air flotation device generally comprises a tank body and an oil spilling cylinder in the middle, wherein the oil spilling cylinder is used for collecting impurities; the liquid level is manually set on the tank body, PID control is carried out at the liquid level, and the floating impurities gathered towards the middle can enter the oil overflow cylinder. Although the control logic is simpler, the debugging is very troublesome, the liquid level is difficult to set due to the phenomena of lower middle liquid level and higher edge when the rotational flow in the equipment is generated, and the better overflow effect can be ensured only by continuous experiments and strict control of the rotational flow speed;
after the equipment moves, the equipment needs to be extremely strictly leveled, otherwise, the originally set liquid level is inaccurate due to the inclination of the equipment, and the liquid level needs to be set again;
moreover, the control mode is greatly influenced by the physical properties of the incoming liquid, and when factors such as viscosity, flow rate, impurity content and the like change, the rotational flow in the equipment also changes correspondingly, so that the overflow flow fluctuates greatly; if the corresponding viscometer, flowmeter and the like are equipped, the equipment cost is greatly increased, a large amount of logic operation is needed, and the cost is greatly increased.
Therefore, a new rotational flow air flotation control method or device is needed to solve the above problems.
Disclosure of Invention
The invention aims to provide a new technical scheme for rotational flow air flotation control.
According to a first aspect of the present invention, there is provided a cyclone air flotation control method, including the steps of:
periodically collecting the oil level in the oil spilling cylinder, and calculating the average liquid level in the current unit time;
comparing the average liquid level with the lowest liquid level of the oil spilling cylinder and the highest liquid level of the oil spilling cylinder, and adjusting the average liquid level with the lowest liquid level of the oil spilling cylinder and the highest liquid level of the oil spilling cylinder according to the comparison result as follows:
when the average liquid level is lower than the lowest liquid level of the oil spilling cylinder, the liquid level of the tank body is controlled to rise until the average liquid level reaches a position between the lowest liquid level of the oil spilling cylinder and the highest liquid level of the oil spilling cylinder;
when the average liquid level is higher than the highest liquid level of the oil spilling cylinder, the liquid level of the tank body is controlled to fall until the average liquid level reaches a position between the lowest liquid level of the oil spilling cylinder and the highest liquid level of the oil spilling cylinder;
and when the average liquid level is between the lowest liquid level of the oil spilling cylinder and the highest liquid level of the oil spilling cylinder, the liquid level of the tank body is kept unchanged.
Preferably, the mode of controlling the liquid level of the tank body to rise is as follows: adjusting the set value of the liquid level of the tank body upwards, and performing PID control around the adjusted set value of the liquid level of the tank body;
the mode of controlling the liquid level of the tank body to descend is as follows: and (4) adjusting the set value of the liquid level of the tank body downwards, and performing PID control around the adjusted set value of the liquid level of the tank body.
Preferably, the average level is calculated by: and collecting the oil level in the oil overflow cylinder for multiple times in unit time, and averaging to obtain an average liquid level.
Preferably, the set value of the liquid level of the tank body is adjusted only once in unit time, and the value adjusted each time is a fixed value.
Preferably, the oil drain control valve is closed when the average level is below a minimum safe level for the spill barrel.
According to a second aspect of the invention, a rotational flow air flotation device adopting the rotational flow air flotation control method is provided, and the rotational flow air flotation device comprises a tank body and an oil overflow cylinder arranged in the middle of the tank body, wherein liquid level sensors are arranged in the tank body and the oil overflow cylinder, a liquid inlet control valve is arranged on the tank body, an oil discharge control valve is arranged on the oil overflow cylinder, and the liquid level sensors, the liquid inlet control valve and the oil discharge control valve are electrically connected to a processing device.
According to one embodiment of the disclosure, the rotational flow air flotation control method or the control device can automatically adjust the set value of the liquid level of the tank body according to the medium oil level of the oil overflow cylinder, and the floating set value of the liquid level of the tank body can automatically find the height of the edge of the oil overflow cylinder, so that the method and the control device are suitable for oil discharge and slag removal operation under different working conditions and ensure the optimal oil discharge and slag removal effect;
the debugging of the equipment is facilitated, the optimal tank body liquid level value does not need to be calculated through multiple experiments, only the initial value needs to be set, and the debugging time is greatly reduced;
the method is not influenced by the levelness precision of the equipment, and the equipment does not need to be debugged again after being moved and reinstalled;
is not influenced by the factors of the flow rate of the incoming liquid, the viscosity, the content of impurities and the like.
Other features of the present invention and advantages thereof will become apparent from the following detailed description of exemplary embodiments thereof, which proceeds with reference to the accompanying drawings.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description, serve to explain the principles of the invention.
Fig. 1 is a schematic structural view of a rotational flow air flotation control device according to an embodiment of the present invention.
Detailed Description
Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that: the relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise.
The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.
Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate.
In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values.
It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.
Examples
The rotational flow air flotation control method in the embodiment comprises the following steps:
s1: periodically collecting the oil level in the oil spilling cylinder, and calculating the average liquid level in the current unit time;
in this step, the average level is calculated by: and collecting the oil level in the oil overflow cylinder for multiple times in unit time, and averaging to obtain an average liquid level.
The unit time is preset and can be adjusted, for example, 5 minutes is taken as a period, five oil level values are collected in each period, and the five oil level values are averaged to obtain an average liquid level.
S2: comparing the average liquid level with the lowest liquid level of the oil spilling cylinder and the highest liquid level of the oil spilling cylinder, and adjusting the average liquid level with the lowest liquid level of the oil spilling cylinder and the highest liquid level of the oil spilling cylinder according to the comparison result as follows:
s21: when the average liquid level is lower than the lowest liquid level of the oil spilling cylinder, the liquid level of the tank body is lower, and impurities swirling to the center are difficult to reach the edge of the oil spilling cylinder, so that the liquid level of the tank body is controlled to rise until the average liquid level reaches the position between the lowest liquid level of the oil spilling cylinder and the highest liquid level of the oil spilling cylinder;
the mode of controlling the liquid level of the tank body to rise in the step is as follows: the set value of the liquid level of the tank body is adjusted upwards, and PID control is carried out around the set value of the liquid level of the tank body after the adjustment, so that the liquid level of the tank body is in a dynamic and stable state;
s22: when the average liquid level is higher than the highest liquid level of the oil spilling cylinder, the liquid level of the tank body is higher, and a large amount of water enters the oil spilling cylinder, so that the liquid level of the tank body is controlled to be reduced until the average liquid level reaches a position between the lowest liquid level of the oil spilling cylinder and the highest liquid level of the oil spilling cylinder;
the mode of controlling the liquid level of the tank body to descend is as follows: the set value of the liquid level of the tank body is adjusted downwards, and PID control is carried out around the adjusted set value of the liquid level of the tank body, so that the liquid level of the tank body is in a dynamic and stable state
S23: when the average liquid level is between the lowest liquid level of the oil spilling cylinder and the highest liquid level of the oil spilling cylinder, the liquid level of the oil spilling cylinder is at the optimal oil discharge level, and at the moment, the current liquid level in the tank body is in a good state in cooperation with the oil spilling cylinder, so that the liquid level of the tank body is kept unchanged.
The lowest liquid level of the oil spilling cylinder and the highest liquid level of the oil spilling cylinder are preset values, and can be modified according to actual conditions, so that the optimal overflowing effect is ensured;
the set value of the liquid level of the tank body can be set to a value at any time in the initial period, after the equipment is started, the system automatically searches the optimal overflow liquid level according to the method, and the initially set value is positioned below the edge of the overflow cylinder, so that a large amount of water is prevented from entering the overflow cylinder.
In this embodiment or other embodiments, the set value of the liquid level of the tank body is adjusted only once in a unit time, the value adjusted each time is a fixed value, and the fixed value can be manually set, for example, 1mm, if the unit time is 5min, namely, 1mm is adjusted every 5 minutes, so that the situation that the optimal liquid level is exceeded due to too fast adjustment speed or the slag discharge effect is affected due to a large amount of water rushing into the oil overflow cylinder due to too fast adjustment speed is avoided.
In this or other embodiments, the drain control valve is closed when the average level is below the minimum safe level for the spill barrel. Preventing gas from entering a downstream pipeline to influence the normal operation of equipment; the lowest safe liquid level is a preset value, and the height of the lowest safe liquid level is lower than the lowest liquid level of the oil overflow cylinder.
In this embodiment, a rotational flow air flotation device using the rotational flow air flotation control method is further provided, and includes a tank 100 and an oil overflow cylinder 200 disposed in the middle of the tank 100, liquid level sensors (not shown in the figure) are disposed in the tank 100 and the oil overflow cylinder 200, a liquid inlet control valve 131 is disposed on the tank 100, an oil discharge control valve 211 is disposed on the oil overflow cylinder 200, and the liquid level sensors, the liquid inlet control valve 131, and the oil discharge control valve 211 are all electrically connected to a processing device (not shown in the figure).
The processing device is, for example, a PLC system, a single chip microcomputer system, or a microcomputer, and can receive, process, and store data, and can transmit processed information or instructions to the liquid inlet control valve 131 and the oil discharge control valve 211.
The tank 100 in this embodiment includes an inner cylinder 120 and an outer cylinder 110, the inner cylinder 120 is disposed at the middle of the outer cylinder 110, an oil overflow cylinder 200 is disposed at the top middle of the inner cylinder 120 and higher than the inner cylinder 120, and a liquid level sensor detects a liquid level of the outer cylinder 110 and an oil level in the oil overflow cylinder 200, respectively. The liquid inlet pipe 130 is communicated with the inner cylinder 120 and is controlled by a liquid inlet control valve 131; the drain pipe 140 is connected to the outer tub 110; the bottom of the oil overflow cylinder 200 is communicated with a row 210 which is controlled by an oil discharge control valve 211.
When the device is used, sewage to be treated enters the inner cylinder and continuously rises to reach a preset liquid level set value of the tank body; meanwhile, a liquid level sensor in the oil overflow cylinder periodically detects the average liquid level of the oil level, the set value of the liquid level of the tank body is subjected to floating regulation according to the average liquid level, and meanwhile, PID dynamic control is carried out according to the current set value of the liquid level of the tank body, so that a stable oil overflow effect is kept.
No matter the liquid supply fluctuation is large or the physical property of the liquid supply changes, when the oil spilling effect in the oil spilling cylinder changes, the oil spilling cylinder can be automatically adjusted to achieve the optimal oil spilling effect.
According to one embodiment of the disclosure, the rotational flow air flotation control method or the control device can automatically adjust the set value of the liquid level of the tank body according to the medium oil level of the oil overflow cylinder, and the floating set value of the liquid level of the tank body can automatically find the height of the edge of the oil overflow cylinder, so that the rotational flow air flotation control method or the control device is suitable for oil discharge and slag removal operation under different working conditions and ensures the optimal oil discharge and slag removal effect;
the debugging of the equipment is facilitated, the optimal tank body liquid level value does not need to be calculated through multiple experiments, only the initial value needs to be set, and the debugging time is greatly reduced;
the method is not influenced by the levelness precision of the equipment, and the equipment does not need to be debugged again after being moved and reinstalled;
is not influenced by the factors of the flow rate of the incoming liquid, the viscosity, the content of impurities and the like.
Although some specific embodiments of the present invention have been described in detail by way of examples, it should be understood by those skilled in the art that the above examples are for illustrative purposes only and are not intended to limit the scope of the present invention. It will be appreciated by those skilled in the art that modifications may be made to the above embodiments without departing from the scope and spirit of the invention. The scope of the invention is defined by the appended claims.
Claims (6)
1. A rotational flow air flotation control method is characterized by comprising the following steps:
periodically collecting the oil level in the oil spilling cylinder, and calculating the average liquid level in the current unit time;
comparing the average liquid level with the lowest liquid level of the oil spilling cylinder and the highest liquid level of the oil spilling cylinder, and adjusting the average liquid level with the lowest liquid level of the oil spilling cylinder and the highest liquid level of the oil spilling cylinder according to the comparison result as follows:
when the average liquid level is lower than the lowest liquid level of the oil spilling cylinder, the liquid level of the tank body is controlled to rise until the average liquid level reaches a position between the lowest liquid level of the oil spilling cylinder and the highest liquid level of the oil spilling cylinder;
when the average liquid level is higher than the highest liquid level of the oil spilling cylinder, the liquid level of the tank body is controlled to fall until the average liquid level reaches a position between the lowest liquid level of the oil spilling cylinder and the highest liquid level of the oil spilling cylinder;
and when the average liquid level is between the lowest liquid level of the oil spilling cylinder and the highest liquid level of the oil spilling cylinder, the liquid level of the tank body is kept unchanged.
2. The cyclone air flotation control method according to claim 1, wherein the mode of controlling the liquid level of the tank body to rise is as follows: adjusting the set value of the liquid level of the tank body upwards, and performing PID control around the adjusted set value of the liquid level of the tank body;
the mode of controlling the liquid level of the tank body to descend is as follows: and (4) adjusting the set value of the liquid level of the tank body downwards, and performing PID control around the adjusted set value of the liquid level of the tank body.
3. The cyclone air flotation control method according to claim 2, wherein the average liquid level is calculated in the following manner: and collecting the oil level in the oil overflow cylinder for multiple times in unit time, and averaging to obtain an average liquid level.
4. The cyclone air-flotation control method according to claim 2, wherein the set value of the liquid level of the tank body is adjusted only once in unit time, and the value adjusted each time is a fixed value.
5. The cyclone air-flotation control method according to claim 1, wherein the oil discharge control valve is closed when the average liquid level is lower than the minimum safe liquid level of the oil overflow cylinder.
6. A cyclone air-flotation device adopting the cyclone air-flotation control method as claimed in any one of claims 1 to 5, which is characterized by comprising a tank body and an oil overflow cylinder arranged in the middle of the tank body, wherein liquid level sensors are arranged in the tank body and the oil overflow cylinder, a liquid inlet control valve is arranged on the tank body, an oil discharge control valve is arranged on the oil overflow cylinder, and the liquid level sensors, the liquid inlet control valve and the oil discharge control valve are electrically connected to a processing device.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202210254320.4A CN114538552A (en) | 2022-03-15 | 2022-03-15 | Rotational flow air flotation control method and rotational flow air flotation equipment |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202210254320.4A CN114538552A (en) | 2022-03-15 | 2022-03-15 | Rotational flow air flotation control method and rotational flow air flotation equipment |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103922497A (en) * | 2014-04-14 | 2014-07-16 | 中国石油大学(华东) | Three-stage pressure-reducing V-shaped hydraulic cyclone air floatation device |
| CN206081760U (en) * | 2016-10-19 | 2017-04-12 | 大庆华谊金鹰石油科技有限公司 | It receives oily controlling means to integrate intelligent oil field wastewater pot |
| CN208741997U (en) * | 2018-07-09 | 2019-04-16 | 吉林省一机分离机械制造股份有限公司 | A kind of perseverance liquid-level auto-control device |
| CN110806243A (en) * | 2019-10-10 | 2020-02-18 | 广州市威控机器人有限公司 | Liquid level detection method, liquid level detection equipment and computer readable storage medium |
| CN215327063U (en) * | 2021-04-30 | 2021-12-28 | 山东鲁润环保工程有限公司 | Rotational flow air flotation equipment |
-
2022
- 2022-03-15 CN CN202210254320.4A patent/CN114538552A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103922497A (en) * | 2014-04-14 | 2014-07-16 | 中国石油大学(华东) | Three-stage pressure-reducing V-shaped hydraulic cyclone air floatation device |
| CN206081760U (en) * | 2016-10-19 | 2017-04-12 | 大庆华谊金鹰石油科技有限公司 | It receives oily controlling means to integrate intelligent oil field wastewater pot |
| CN208741997U (en) * | 2018-07-09 | 2019-04-16 | 吉林省一机分离机械制造股份有限公司 | A kind of perseverance liquid-level auto-control device |
| CN110806243A (en) * | 2019-10-10 | 2020-02-18 | 广州市威控机器人有限公司 | Liquid level detection method, liquid level detection equipment and computer readable storage medium |
| CN215327063U (en) * | 2021-04-30 | 2021-12-28 | 山东鲁润环保工程有限公司 | Rotational flow air flotation equipment |
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