An oil-containing sewage deslagging device and method, three-phase separation device and method

Abstract

The present application relates to a kind of oil-containing sewage deslagging device and method, three-phase separation equipment and method.Deslagging device includes box, water inlet unit, partition, weir plate and sewage pump.Water inlet unit is communicated with box, for guiding oil-containing sewage into box.Partition is installed in box, and the inner chamber of box is divided into overflow chamber located above partition and deposition chamber located below partition.Weir plate is fixedly connected with partition.Weir plate is hollow cuboid structure, and the top end of weir plate is sawtooth structure.The present application controls the water inlet rate of oil-containing sewage and heating power by monitoring the temperature and oil content of oil-containing sewage in real time, and timely discharges solid phase waste residue in oil-containing sewage, so that deslagging device operates in the lowest energy consumption range, reduces the energy consumption of oil-containing sewage purification grease by more than 30%, and keeps the oil amount of inlet water and outlet water balanced, improves the efficiency of deslagging and oil-water separation.

Description

Technical Field

[0001] This invention relates to a three-phase separation device, and more particularly to a slag removal device for oily wastewater, a three-phase separation device for oily wastewater, and a three-phase separation method for oily wastewater. Background Technology

[0002] After a series of processes and high-temperature hydrolysis (the slurry temperature should be around 60-80℃), kitchen waste can be separated into three phases: the solid phase (waste residue), the light liquid phase (oil), and the heavy liquid phase (sewage) using a three-phase horizontal screw centrifuge or a disc separator.

[0003] Existing technologies for separating and recycling kitchen wastewater generally suffer from poor separation of oil within the solid phase. Practical experience has shown that temperature and time are the two main influencing factors in the separation process. In the solid-liquid separation process (removing waste residue from the kitchen wastewater), gravity separation is mostly used. Because the density of the solid waste residue in kitchen wastewater is greater than that of water, it automatically settles to the bottom after a period of settling. When a certain amount of solid waste residue accumulates, it can be discharged all at once. During this process, to ensure the fluidity of the liquid phase oil and water, the kitchen wastewater can be heated to melt the solid oil into liquid oil. Currently, the melting process of the solid oil is often accomplished by heating at a fixed temperature or power, which inevitably consumes additional energy and increases the overall operating cost of the three-phase separation. Summary of the Invention

[0004] Therefore, it is necessary to address the problem of high energy consumption in the existing three-phase separation process of oily wastewater by providing a slag removal device and method, as well as a three-phase separation device and method for oily wastewater.

[0005] The present invention is achieved through the following technical solution: a slag removal device for oily wastewater, the slag removal device comprising a tank, a water inlet unit, a baffle plate, a weir plate, a heating unit, a sewage pump, a data acquisition unit, and a controller.

[0006] The tank has through holes on its side walls. An inlet unit connects to the tank and is used to introduce oily wastewater into it. A baffle plate is installed inside the tank, dividing the interior into an overflow chamber above the baffle plate and a sedimentation chamber below it. One side of the baffle plate is located directly below the through holes, and the other side is inclined upwards. A weir plate is fixedly connected to the baffle plate. The weir plate is a hollow cuboid structure with a serrated top. The interior of the weir plate connects the overflow chamber and the sedimentation chamber. A heating unit is installed on the outside of the tank. The heating unit includes heater one and heater two. Heater one heats the oily wastewater inside the weir plate. Heater two heats the oily wastewater inside the sedimentation chamber. A sewage pump connects to the bottom of the tank and is used to discharge solid waste from the tank. A collection unit is used to collect the initial oil content ω0, the upper limit temperature T1, and the oil content ω1 of the oily wastewater, as well as the lower limit temperature T2 and the oil content ω2 of the oily wastewater. The upper limit is set at the bottom of the weir plate, and the lower limit is set in the middle of the sedimentation chamber.

[0007] The controller is used to: 1. When the level of oily wastewater reaches the lower limit, control the heater 2 to operate at maximum power P. max2 Operation. When the oily wastewater level reaches the upper limit, determine whether T1 is higher than a preset temperature T. e Therefore, the heater is controlled according to the minimum power P. min1 Run, otherwise control the heater to operate at maximum power P. max1 run.

[0008] 2. Determine if T2 is lower than a preset temperature T. e Therefore, the heater is controlled according to the maximum power P. max2 Run. Otherwise, control heater two to operate at minimum power P. min2 run.

[0009] III. Determine whether ω1 is greater than a preset oil content ω e If so, the influent rate is kept constant; otherwise, the ideal influent rate v is calculated and adjusted to v. Oil content ω e Expressed as:

[0010]

[0011] The ideal influent rate v is expressed as:

[0012]

[0013] in, This represents the average oil content of the influent during the previous cycle. The inflow rate in the previous cycle. The ideal oil content for the average drainage during the current cycle.

[0014] IV. Determine if ω2 is lower than a preset oil content ω n This controls the operation of the sewage pump, discharging all the kitchen oil and water below the lower limit.

[0015] The aforementioned slag removal device, by incorporating serrated weir plates, not only filters out suspended solids and reduces the impurity content in the recovered oil from oily wastewater, but also allows the oily wastewater to diffuse outwards along the top of the weir plates, improving the flow capacity of the liquid phase oil and water. Furthermore, by monitoring the temperature and oil content of the oily wastewater in real time, the operating status of the heating unit and the water purification device can be controlled separately to ensure the slag removal device operates within the lowest energy consumption range. This reduces the energy consumption for purifying oil from oily wastewater by more than 30%, maintains a balance between the influent and effluent oil volumes, and improves the efficiency of slag removal and oil-water separation.

[0016] In one embodiment, heater one uses a carbon fiber heating plate with a rated power of 200W. Heater two uses a carbon fiber heating plate with a rated power of 600W.

[0017] In one embodiment, the inlet unit includes a submersible pump and an inlet pipe. The submersible pump is installed in a sump for storing oily wastewater. One end of the inlet pipe is connected to the submersible pump, and the other end is connected to a sedimentation chamber.

[0018] The present invention also provides a method for removing sludge from oily wastewater, the method comprising the following steps:

[0019] S1: Collects the initial oil content ω0, the upper limit temperature T1, and the oil content ω1 of the oily wastewater, as well as the lower limit temperature T2 and the oil content ω2 of the oily wastewater. The upper limit is set at the bottom of the weir plate of the slag removal device, and the lower limit is set in the middle of the sedimentation chamber of the slag removal device.

[0020] S2: When the level of the oily wastewater reaches the lower limit, a preset power P is applied. max2 The oily wastewater in the sedimentation chamber is heated. When the oily wastewater level reaches the upper limit, it is determined whether T1 is higher than a preset temperature T. e Therefore, according to power P min1 The oily wastewater inside the weir is heated; otherwise, it is heated according to power P. max1 The oily wastewater inside the weir plate is heated.

[0021] S3: Determine if T2 is lower than a preset temperature T. e Therefore, according to power P max2 The oily wastewater in the sedimentation chamber is heated. Otherwise, the power is controlled according to P. min2 The oily wastewater in the sedimentation chamber is heated.

[0022] S4: Determine if ω1 is greater than a preset oil content ω e If the inflow rate of the oily wastewater is constant, then the ideal inflow rate v of the oily wastewater is calculated, and the oily wastewater is controlled to be introduced into the sedimentation chamber at a rate v. Oil content ω e Expressed as:

[0023]

[0024] The ideal influent rate v is expressed as:

[0025]

[0026] in, This represents the average oil content of the influent during the previous cycle. The inflow rate in the previous cycle. The ideal oil content for the average drainage during the current cycle.

[0027] S5: Determine if ω2 is lower than a preset oil content ω n If so, all solid waste and liquid oil and water below the lower limit will be discharged.

[0028] The present invention also provides a three-phase separation device for oily wastewater, the three-phase separation device including a slag removal device, an oil-water separation tank, a discharge device, an oil content detector, a heating device, and a stirring device.

[0029] The oil-water separator is connected to the through-hole of the sludge removal device via a pipe. The oil-water separator is used to separate oil and water in oily wastewater through static sedimentation. A discharge device is installed on the oil-water separator to remove the oil and water from the separator.

[0030] In one embodiment, the discharge device includes a drain pipe, a three-way valve, and an oil tank. One end of the drain pipe is connected to the bottom of an oil-water separator. The three-way valve includes an inlet, an oil outlet, and a drain outlet. The inlet of the three-way valve is connected to the other end of the drain pipe. The oil outlet of the three-way valve is connected to the oil tank for oil recovery. The drain outlet of the three-way valve is used for draining water.

[0031] In one embodiment, an oil content detector is installed at the connection between the oil-water separator and the discharge device to detect the oil content of the oily wastewater at the bottom of the oil-water separator.

[0032] In one embodiment, a heating device is installed on the oil-water separator to heat the oily wastewater inside the oil-water separator.

[0033] In one embodiment, a stirring device is installed inside the oil-water separator to stir the oily wastewater inside the oil-water separator.

[0034] This invention also provides a three-phase separation method for oily wastewater, the three-phase separation method comprising the following steps:

[0035] S10: The above-mentioned method for removing sludge from oily wastewater is used to remove sludge from the oily wastewater.

[0036] S20: Oil-water separation: S201: Heating and stirring the liquid phase oil and water in the oil-water separator. Heating and stirring are stopped when the temperature of the liquid phase oil and water in the separator exceeds a preset threshold. S202: Using a static sedimentation method, the liquid phase oil and water are separated into an oil layer and a water layer within the oil-water separator. S203: Determining the oil content ω of the liquid phase oil and water at the bottom of the oil-water separator. j Is it below a preset oil content ω? n If yes, the liquid phase oil and water will be discharged. Otherwise, the liquid phase oil and water will be recovered.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] 1. The slag removal device of the present invention divides the inner cavity of the tank into a sedimentation chamber and an overflow chamber that are connected vertically by setting a baffle and a weir plate. Oily wastewater is then introduced into the tank from the top of the sedimentation chamber through a water inlet device. The oily wastewater settles under gravity, solid waste is deposited at the bottom of the sedimentation chamber, and the liquid oil-water mixture flows into the overflow chamber after the solid suspended matter is filtered out by the weir plate, and is then discharged through the through-hole. By setting a serrated weir plate, not only can solid suspended matter be filtered out, reducing the impurity content in the recovered oil from the oily wastewater, but the oily wastewater also diffuses outwards along the top of the weir plate, improving the flow capacity of the liquid oil-water mixture. Furthermore, by setting upper and lower limit switches, the temperature and oil content of the oily wastewater are monitored in real time, thereby controlling the operating status of the heating unit and the water purification device respectively, so that the slag removal device operates within the lowest energy consumption range, reducing the energy consumption for purifying oil from oily wastewater by more than 30%, and maintaining a balance between the influent and effluent oil volumes, thus improving the efficiency of slag removal and oil-water separation. In summary, the slag removal device of the present invention has the characteristics of high slag removal efficiency, low operating cost, and improved oil-water separation efficiency.

[0039] 2. The three-phase separation equipment of this invention employs a slag removal device to remove slag from oily wastewater, allowing the oily wastewater to initially settle. While discharging solid waste, it maintains the fluidity of the liquid oil-water phase, improving the efficiency of oil-water separation. Simultaneously, during the oil-water separation process, heating and stirring ensure uniform temperature rise of the liquid oil-water phase, improving temperature control accuracy and reducing energy consumption. The three-phase separation equipment of this invention features energy saving, environmental protection, and high-efficiency separation. Attached Figure Description

[0040] Figure 1 This is a three-dimensional structural schematic diagram of the three-phase separation device for oily wastewater according to Embodiment 1 of the present invention;

[0041] Figure 2 for Figure 1 A cross-sectional schematic diagram of the three-dimensional structure of the slag removal device;

[0042] Figure 3 for Figure 1 A cross-sectional schematic diagram of the three-dimensional structure of the oil-water separator;

[0043] Figure 4 This is a flowchart illustrating the three-phase separation method for oily wastewater according to Embodiment 1 of the present invention;

[0044] Figure 5 for Figure 4 A flowchart of the slag removal method. Detailed Implementation

[0045] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0046] It should be noted that when a component is said to be "installed on" another component, it can be directly on the other component or it may be in a component that is centered on it. When a component is said to be "set on" another component, it can be directly set on the other component or it may also be in a component that is centered on it. When a component is said to be "fixed to" another component, it can be directly fixed to the other component or it may also be in a component that is centered on it.

[0047] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "or / and" as used herein includes any and all combinations of one or more of the associated listed items.

[0048] Example 1

[0049] Please see Figure 1 This is a three-dimensional structural diagram of the three-phase separation equipment for oily wastewater in this embodiment. The three-phase separation equipment includes: a slag removal device 10, an oil-water separation tank 20, a discharge device 30, an oil content detector 40, a heating device 50, and a stirring device 60. The slag removal device 10, as the front-end device of the three-phase separation setup, is used to remove solid waste residue from the oily wastewater.

[0050] Please combine Figure 2 , it is Figure 1A cross-sectional schematic diagram of the three-dimensional structure of the slag removal device. The slag removal device 10 includes a housing 1, a water inlet unit 2, a baffle plate 3, a weir plate 4, a heating unit 5, a sewage pump 6, a data acquisition unit (not shown) and a controller 7.

[0051] The side wall of the housing 1 has through holes. In this embodiment, the housing 1 includes an upper shell, a lower shell, and four supporting legs. The upper shell is a hollow cuboid, and the lower shell is a hollow truncated pyramid. The upper shell and the lower shell are fixedly connected, thus forming an inner cavity for treating oily wastewater. The four supporting legs are fixedly connected to the outer wall of the lower shell to provide support for the housing 1, so that the lower shell is higher than the mounting surface of the supporting legs. The housing 1 is made entirely of stainless steel, which not only has high hardness, sufficient to provide adequate support when filled with oily wastewater, but also has high corrosion resistance, enabling it to treat oily wastewater for a long time without being corroded, thus maintaining the treatment efficiency of oily wastewater. Of course, in other embodiments, the housing 1 can also be a hollow cylinder, a hollow sphere, or other structures. The housing 1 can also be made of ceramic materials, plastic materials (such as PE, ABS, PP, etc.), or other metal materials (such as aluminum alloy, etc.).

[0052] The partition 3 is a hollow, single-line plate. Installed inside the housing 1, the partition 3 divides the inner cavity of the housing 1 into an overflow chamber above the partition 3 and a sedimentation chamber below the partition 3. The overflow chamber and the sedimentation chamber are connected through a central hole in the partition 3. One side of the partition 3 is located directly below the through hole, and the other side of the partition 3 is inclined upwards. In this embodiment, the sedimentation chamber is an inverted truncated pyramid. Oily wastewater settles within the housing 1, solid waste is deposited along the inner wall of the lower shell at the bottom of the sedimentation chamber, while the liquid phase oil and water first rises to the overflow chamber and then is discharged through the through hole.

[0053] Weir plate 4 is fixedly connected to partition plate 3. Weir plate 4 is a hollow cuboid structure with a serrated top. The inner cavity of weir plate 4 has the same diameter as the central hole of partition plate 3, thus connecting the overflow chamber and the sedimentation chamber through the inner cavity of weir plate 4. The top surface of weir plate 4 is parallel to the horizontal plane. When the level of oily wastewater reaches the top of weir plate 4, suspended waste particles larger than the serrated holes in the oily wastewater are filtered out through the serrated structure, while the oil and water flow into the overflow chamber through the serrated holes. Partition plate 3 and weir plate 4 can be made of the same material as the housing 1, or other plastic or metal materials, as long as they have sufficient hardness and corrosion resistance to maintain long-term operation without deformation or corrosion.

[0054] The inlet unit 2 is connected to the tank body and is used to introduce oily wastewater into the tank body. The inlet unit 2 includes a submersible pump and an inlet pipe. The submersible pump is installed in a sump for storing oily wastewater. One end of the inlet pipe is connected to the submersible pump, and the other end is connected to the sedimentation chamber. The submersible pump is started to introduce the oily wastewater from the sump into the sedimentation chamber. The oily wastewater accumulates from the bottom of the sedimentation chamber and gradually rises into the inner cavity of the weir plate 4. During this process, the solid waste and liquid oil-water in the oily wastewater gradually separate under gravity. The solid waste settles at the bottom of the sedimentation chamber, while the liquid oil-water flows through the top of the weir plate 4 into the overflow chamber.

[0055] Heating unit 5 is installed on the outside of the tank. The heating unit includes heater 51 and heater 52. Heater 51 is used to heat the oily wastewater within the weir plate. Heater 52 is used to heat the oily wastewater within the sedimentation chamber.

[0056] Heater 1 (51) uses a carbon fiber heating plate with a rated power of 200W. Heater 2 (52) uses a carbon fiber heating plate with a rated power of 600W. The carbon fiber heating plate is a high-polymer heating material. It overcomes the shortcomings of traditional heating plates, such as easy breakage due to overcurrent between electrodes, over-oxidation of the heating element, easy detachment, low insulation strength, poor safety performance, and short service life. It offers advantages such as rapid heating, surface heating, uniform heat dissipation, high efficiency and energy saving, no pollution, safety and reliability, and long service life. The electrothermal conversion rate of the carbon fiber heating plate is over 92%. Of course, in other embodiments, heaters 1 (51) and 2 (52) can also use other heating devices such as infrared heaters.

[0057] The sewage pump 6 is connected to the bottom of the tank 1 and is used to discharge solid waste residue inside the tank 1. Solid waste residue in oily wastewater accumulates in the sedimentation chamber of the tank 1. When the solid waste residue is higher than a set height, it will interfere with the slag removal process of the oily wastewater. Therefore, it is necessary to discharge the accumulated solid waste residue in a timely manner.

[0058] The data acquisition unit is used to collect the initial oil content ω0, the temperature T1 and oil content ω1 of the upper limit oily wastewater, and the temperature T2 and oil content ω2 of the lower limit oily wastewater. The upper limit is located at the bottom of the weir plate, and the lower limit is located in the middle of the sedimentation chamber. The data acquisition unit can employ an oil content detection device and a temperature sensor. The oil content detection device is used to monitor the initial oil content ω0, the upper limit oil content ω1, and the lower limit oil content ω2 of the oily wastewater in real time when it enters the system. The temperature sensor is used to monitor the temperature T1 of the upper limit oily wastewater and the temperature T2 of the lower limit oily wastewater in real time.

[0059] Controller 7 is used to: 1. When the level of oily wastewater reaches the lower limit, control heater 2 52 to operate at maximum power P. max2Operation. When the oily wastewater level reaches the upper limit, determine whether T1 is higher than a preset temperature T. e Therefore, the heater 51 is controlled according to the minimum power P. min1 Run, otherwise control heater 51 according to maximum power P max1 Operation. During the initial slag removal or after the solid waste is discharged, the oily wastewater level inside tank 1 is below the lower limit. The oily wastewater in the collection pit is introduced into tank 1 through the water inlet device 2, and the oily wastewater level gradually rises until it reaches the lower limit. At this point, heater 2 52 is activated to heat the oily wastewater. Initially, heater 2 52 operates at its rated power. When the level continues to rise to the upper limit, it is first determined whether the oily wastewater has reached the preset temperature. If the oily wastewater has reached the preset temperature, it indicates that the solid oil in the oily wastewater has been converted into liquid oil, which can flow freely through the top of the weir plate 4. At this time, heater 1 51 only needs to use the preset minimum power P. min1 The system is operated to keep the oily wastewater warm. If the oily wastewater has not reached the preset temperature, the operating power of heater 51 is adjusted to its rated power to heat the oily wastewater to the preset temperature so that all the solid oil in the oily wastewater is converted into liquid oil.

[0060] In this embodiment, the preset temperature T e The preset temperature is set to 40°C. In other embodiments, the preset temperature can be set according to the actual melting point of the oil, and can be higher or lower, as long as the oil is always in the liquid phase. Of course, the preset temperature should not be too high to avoid extra power consumption and increased operating costs.

[0061] 2. Determine if T2 is lower than a preset temperature T. e Therefore, the heater 252 is controlled according to the maximum power P. max2 Run. Otherwise, control heater 252 to operate at minimum power P. min2 Operation. When heater 52 heats the oily wastewater in tank 1, if the inflow rate of the oily wastewater is high, the temperature rise rate of the oily wastewater is relatively low. When the oily wastewater level reaches the upper limit, if the oily wastewater at the lower limit has not yet reached the preset temperature, heater 52 continues to operate at its rated power. If the inflow rate of the oily wastewater is low and the temperature rise rate of the oily wastewater is high, then when the oily wastewater at the lower limit reaches the preset temperature, the power of heater 52 is adjusted to the preset minimum power P. min2 run.

[0062] III. Determine whether ω1 is greater than a preset oil content ω e If so, the water inflow rate is kept constant; otherwise, the ideal water inflow rate v is calculated and adjusted to v.

[0063] Under the influence of gravity, the oil and water components in oily wastewater partially separate, resulting in an oil content ω1 in the upper limit of the oily wastewater being higher than the oil content ω2 in the lower limit. However, since the initial oil content ω0 of the influent oily wastewater varies, the oil content ω1 in the upper limit may be lower than the preset discharge standard. Therefore, it is necessary to adjust the influent rate to balance the real-time oil discharge with the real-time oil influent.

[0064] When the oil content ω0 of the influent is not higher than 0.01, it is close to the discharge standard. Therefore, the preset oil content ω0 is set. e The value is set to 0.02, allowing the oily wastewater to stratify within tank 1. Wastewater below the discharge standard is then quickly discharged, reducing the amount of oily wastewater processed during oil-water separation, thereby improving treatment efficiency and lowering costs. Similarly, when the oil content ω0 of the influent is not less than 0.05, the oily wastewater is considered suitable for direct oil-water separation, and the preset oil content ω0 is set accordingly. e The value is set to 0.05 to quickly introduce oily wastewater into the oil-water separation device, improving the efficiency of oil-water separation. When the oil content ω0 of the influent is between 0.01 and 0.05, the preset oil content ω0 increases with the increase of oil content. e The oil content ω0 gradually approaches equalness. Therefore, the preset oil content ω e Expressed as:

[0065]

[0066] To achieve a balance between the influent and effluent of oily wastewater, an adjustment cycle can be set, and the influent rate, average oil content of the influent, and average oil content of the effluent from the previous cycle can be collected separately. The oil content in the influent oily wastewater during the previous cycle can then be expressed as: Therefore, the amount of oil discharged in the current cycle should be equal to... ,Right now .

[0067] After simplification, the ideal influent rate v is expressed as:

[0068]

[0069] in, This represents the average oil content of the influent during the previous cycle. The inflow rate in the previous cycle. The ideal oil content for the average drainage during the current cycle can be determined by the oil content ω mentioned above. e The expression is calculated from this.

[0070] IV. Determine if ω2 is lower than a preset oil content ω nThis controls the operation of sewage pump 6 to discharge all kitchen oil and water below the lower limit. When ω2 < ω n When the lower limit is set, it indicates that the oily wastewater below the lower limit has met the discharge standards and can be discharged directly. By setting the lower limit and waiting for the initial separation of oily wastewater, the solid waste and water are discharged together. This not only reduces the number of times the slag is discharged and ensures smooth slag discharge, but also discharges the deposited solid waste in a timely manner, prolongs the residence time of oily wastewater in tank 1, and improves the efficiency of slag removal.

[0071] In this embodiment, the slag removal device 10 divides the inner cavity of the tank 1 into a sedimentation chamber and an overflow chamber that are connected vertically by a partition 3 and a weir plate 4. Oily wastewater is then introduced into the tank 1 from the top of the sedimentation chamber through the water inlet device 2. The oily wastewater settles under gravity, with solid waste settling at the bottom of the sedimentation chamber. The liquid phase oil-water flows into the overflow chamber after the solid suspended matter is filtered out by the weir plate, and is then discharged through the through-hole. By setting the serrated weir plate 4, not only can the solid suspended matter be filtered out, reducing the impurity content in the recovered oil from the oily wastewater, but the oily wastewater also diffuses outwards along the top of the weir plate 4, improving the flow capacity of the liquid phase oil-water. Furthermore, by setting upper and lower limits, the temperature and oil content of the oily wastewater are monitored in real time, thereby controlling the operating status of the heating unit 5 and the water purification device 2 respectively. This ensures that the slag removal device 10 operates within the lowest energy consumption range, reducing the energy consumption for purifying oil from the oily wastewater by more than 30%, and maintaining a balance between the influent and effluent oil volumes, thus improving the efficiency of slag removal and oil-water separation. In summary, the slag removal device 10 of this embodiment features high slag removal efficiency, low operating cost, and improved oil-water separation efficiency.

[0072] Please combine Figure 3 , it is Figure 1 A cross-sectional schematic diagram of the three-dimensional structure of the oil-water separator 20. The oil-water separator 20 is connected to the through-hole of the tank 1 via a pipe. The through-hole of the tank 1 is higher than the connection point between the pipe and the oil-water separator 20, ensuring that the liquid oil and water in the overflow chamber of the tank 1 always flow into the oil-water separator 20. To prevent backflow of the liquid oil and water, a one-way valve or electronic valve can be installed on the outside of the pipe, allowing the liquid oil and water to flow only towards the oil-water separator 20. The oil-water separator 20 is used to separate oil and water in oily wastewater by static sedimentation. The liquid oil and water settle within the oil-water separator 20, gradually separating into an upper oil layer and a lower water layer under gravity. Some incompletely separated solid waste also settles to the bottom of the water layer.

[0073] A discharge device 30 is installed on the oil-water separator 20 to discharge the oil and water inside the separator 20. The discharge device 30 includes a drain pipe 301, a three-way valve 302, and an oil tank 303. One end of the drain pipe 301 is connected to the bottom of the oil-water separator 20. The three-way valve 302 includes an inlet end, an oil outlet end, and a drain end. The inlet end of the three-way valve 302 is connected to the other end of the drain pipe 301. The oil outlet end of the three-way valve 302 is connected to the oil tank 303 for oil recovery. The drain end of the three-way valve 302 is used for drainage. After the liquid phase oil and water have completely separated in the oil-water separator 20, the drain end of the three-way valve 302 is first opened to discharge the water layer and all solid waste within it. Then, the drain end is closed, and the oil outlet end is opened to discharge the entire oil layer into the oil tank 303.

[0074] An oil content detector 40 is installed at the connection between the oil-water separator 20 and the discharge device 30 to detect the oil content of the oily wastewater at the bottom of the oil-water separator 20. In actual operation, although completely separated water and oil can be distinguished by color, it is still difficult to precisely distinguish the water layer and the oil layer by manual observation during the discharge process. By using the oil content detector 40 to monitor the oil content of the liquid phase oil-water at the bottom of the oil-water separator 20 in real time, water that meets the discharge conditions can be directly discharged, while oil that meets the recovery conditions can be discharged into the oil tank 303, thus realizing the separation of oil and water and the recovery and reuse of oil. The oil content detector can be an infrared spectrophotometer or a nuclear magnetic resonance oil content analyzer, as long as it can detect the oil content in the wastewater.

[0075] A heating device 50 is installed on the oil-water separator 20 to heat the oily wastewater inside. The heating device 50 can be an infrared heater, a carbon fiber heating plate, or other heating devices, as long as they can heat the liquid phase oil and water to prevent the liquid oil from condensing into solid oil. In this embodiment, a far-infrared heater with a rated power of 40 kW is used. The far-infrared heater uses far-infrared conduction heat transfer; the heating element does not contact the material, eliminating scorching and smoke, and resulting in more uniform heat transfer, higher thermal efficiency, lower energy consumption, and greater energy savings.

[0076] A stirring device 60 is installed inside the oil-water separator 20 to stir the oily wastewater within the separator. In this embodiment, a 1.5kW rated power stirrer is used. The stirrer is started jog-started via a button, stirring for 5 minutes each time, then stopping for 10 minutes. This cycle repeats, and the stirrer is synchronized with the heating device 50, starting and stopping synchronously. Of course, in other embodiments, a stirrer with higher or lower power can be selected, and the stirring time can be longer or shorter each time.

[0077] The three-phase separation equipment in this embodiment employs a slag removal device 10 to remove slag from the oily wastewater, allowing the wastewater to initially settle. While discharging solid waste, it maintains the fluidity of the liquid oil-water phase, improving the efficiency of oil-water separation. Simultaneously, during the oil-water separation process, heating and stirring ensure uniform temperature rise of the liquid oil-water phase, improving temperature control accuracy and reducing energy consumption. The three-phase separation equipment in this embodiment features energy saving, environmental protection, and high-efficiency separation.

[0078] Please see Figure 4 and Figure 5 , Figure 4 This is a flowchart illustrating the three-phase separation method for oily wastewater in this embodiment; Figure 5 for Figure 4 A flowchart of the slag removal method is provided. This embodiment also provides a three-phase separation method for oily wastewater. The three-phase separation method includes the following processes:

[0079] S10: Slag Removal:

[0080] S1: Collect the initial oil content ω0, the temperature T1 and oil content ω1 of the oily wastewater at the upper limit, and the temperature T2 and oil content ω2 of the oily wastewater at the lower limit. The upper limit is set at the bottom of the weir plate 4, and the lower limit is set in the middle of the sedimentation chamber.

[0081] In this embodiment, an oil content detection device is installed at the inlet, upper limit, and lower limit of the oily wastewater to monitor the oil content at these three locations in real time. Simultaneously, a temperature sensor is installed at both the upper and lower limit to monitor the temperature at these limits in real time.

[0082] S2: When the level of the oily wastewater reaches the lower limit, a preset power P is applied. max2 The oily wastewater in the sedimentation chamber is heated. When the oily wastewater level reaches the upper limit, it is determined whether T1 is higher than a preset temperature T. e Therefore, according to power P min1对堰板 Oily wastewater within 4 is heated; otherwise, it is heated according to power P. max1对堰板 The oily wastewater in section 4 is heated.

[0083] During the initial slag removal or after the solid waste is discharged, the oily wastewater level inside tank 1 is below the lower limit. The oily wastewater in the collection pit is then introduced into tank 1, and the level gradually rises until it reaches the lower limit. At this point, the oily wastewater inside tank 1 is heated. Initially, according to power P... max2Heating is then performed. When the liquid level continues to rise to the upper limit, it is first determined whether the oily wastewater has reached the preset temperature. If the oily wastewater has reached the preset temperature, it indicates that the solid oil in the oily wastewater has been converted into liquid oil, which can flow freely through the top of the weir plate 4. At this time, only the preset minimum power P needs to be used. min1对堰板 The oily wastewater within section 4 is heated to maintain its temperature. If the oily wastewater has not yet reached the preset temperature, then power P is used. max1 The oily wastewater is heated to a preset temperature so that all the solid oil in the oily wastewater is converted into liquid oil.

[0084] In this embodiment, the preset temperature T e The preset temperature is set to 40°C. In other embodiments, the preset temperature can be set according to the actual melting point of the oil, and can be higher or lower, as long as the oil is always in the liquid phase. Of course, the preset temperature should not be too high to avoid extra power consumption and increased operating costs.

[0085] S3: Determine if T2 is lower than a preset temperature T. e Therefore, according to power P max2 The oily wastewater in the sedimentation chamber is heated. Otherwise, the power is controlled according to P. min2 The oily wastewater in the sedimentation chamber is heated.

[0086] When heating oily wastewater inside tank 1, a high inflow rate results in a relatively low temperature rise rate. If the oily wastewater level reaches the upper limit but the lower limit has not yet reached the preset temperature, the power P is maintained. max2 The oily wastewater in the sedimentation chamber is heated. If the inflow rate of the oily wastewater is low and the temperature rise rate is high, then when the oily wastewater at the lower limit reaches the preset temperature, power P is used. min2 The oily wastewater in the sedimentation chamber is heated.

[0087] S4: Determine if ω1 is greater than a preset oil content ω e If the inflow rate of the oily wastewater is constant, then the ideal inflow rate v of the oily wastewater is calculated, and the oily wastewater is controlled to be introduced into the sedimentation chamber at a rate v.

[0088] Under the influence of gravity, the oil and water components in oily wastewater partially separate, resulting in an oil content ω1 in the upper limit of the oily wastewater being higher than the oil content ω2 in the lower limit. However, since the initial oil content ω0 of the influent oily wastewater varies, the oil content ω1 in the upper limit may be lower than the preset discharge standard. Therefore, it is necessary to adjust the influent rate to balance the real-time oil discharge with the real-time oil influent.

[0089] When the oil content ω0 of the influent is not higher than 0.01, it is close to the discharge standard. Therefore, the preset oil content ω0 is set. e The value is set to 0.02, allowing the oily wastewater to stratify within tank 1. Wastewater below the discharge standard is then quickly discharged, reducing the amount of oily wastewater processed during oil-water separation, thereby improving treatment efficiency and lowering costs. Similarly, when the oil content ω0 of the influent is not less than 0.05, the oily wastewater is considered suitable for direct oil-water separation, and the preset oil content ω0 is set accordingly. e The value is set to 0.05 to quickly introduce oily wastewater into the oil-water separation device, improving the efficiency of oil-water separation. When the oil content ω0 of the influent is between 0.01 and 0.05, the preset oil content ω0 increases with the increase of oil content. e The oil content ω0 gradually approaches equalness. Therefore, the preset oil content ω e Expressed as:

[0090]

[0091] To achieve a balance between the influent and effluent of oily wastewater, an adjustment cycle can be set, and the influent rate, average oil content of the influent, and average oil content of the effluent from the previous cycle can be collected separately. The oil content in the influent oily wastewater during the previous cycle can then be expressed as: Therefore, the amount of oil discharged in the current cycle should be equal to... ,Right now .

[0092] After simplification, the ideal influent rate v is expressed as:

[0093]

[0094] in, This represents the average oil content of the influent during the previous cycle. The inflow rate in the previous cycle. The ideal oil content for the average drainage during the current cycle can be determined by the oil content ω mentioned above. e The expression is calculated from this.

[0095] S5: Determine if ω2 is lower than a preset oil content ω n If so, all solid waste and liquid oil and water below the lower limit will be discharged.

[0096] When ω2<ω nWhen the lower limit is set, it indicates that the oily wastewater below the lower limit has met the discharge standards and can be discharged directly. By setting the lower limit and waiting for the initial separation of oily wastewater, the solid waste and water are discharged together. This not only reduces the number of times the slag is discharged and ensures smooth slag discharge, but also discharges the deposited solid waste in a timely manner, prolongs the residence time of oily wastewater in tank 1, and improves the efficiency of slag removal.

[0097] S20: Oil-water separation:

[0098] S201: The liquid phase oil and water in the oil-water separator 20 are heated and stirred. When the temperature of the liquid phase oil and water in the oil-water separator 20 exceeds a preset threshold, heating and stirring are stopped. In this embodiment, a temperature sensor 2 is installed in the oil-water separator 20 to monitor the temperature of the liquid phase oil and water in the oil-water separator 20 in real time. The preset threshold is also set to 40°C.

[0099] S202: A static sedimentation method is used to separate the liquid oil and water into an oil layer and a water layer within the oil-water separator. The liquid oil and water are allowed to settle within the oil-water separator 20, gradually separating into an upper oil layer and a lower water layer under the influence of gravity. Some incompletely separated solid waste also settles to the bottom of the water layer.

[0100] S203: Determine the oil content ω of the liquid phase oil and water at the bottom of the oil-water separator. j Is it below a preset oil content ω? n If the oil content is positive, the liquid phase oil and water will be discharged. Otherwise, the liquid phase oil and water will be recycled. In this embodiment, an oil content detector 40 is installed at the connection between the oil-water separator 20 and the discharge device 30 to detect the oil content of the oily wastewater at the bottom of the oil-water separator 20 in real time.

[0101] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0102] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A slag removal device for oily wastewater, used for preliminary separation of oily wastewater to separate solid waste from liquid oil and water, characterized in that, The slag removal device includes: The box body has through holes on its side walls; A water inlet unit, which is connected to the tank body, is used to introduce oily wastewater into the tank body; A partition is installed inside the box to divide the inner cavity of the box into an overflow chamber located above the partition and a deposition chamber located below the partition; one side of the partition is located just below the through hole, and the other side of the partition is inclined upward. A weir plate is fixedly connected to the partition plate; the weir plate is a hollow cuboid structure, and the top of the weir plate has a serrated structure; the inner cavity of the weir plate connects the overflow cavity and the sedimentation cavity. A heating unit is installed on the outside of the housing; the heating unit includes heater one and heater two; heater one is used to heat the oily wastewater in the weir plate; heater two is used to heat the oily wastewater in the sedimentation chamber; A sewage pump, which is connected to the bottom of the tank, is used to discharge solid waste residue from the tank. A data acquisition unit is used to acquire the initial oil content ω0, the upper limit temperature T1 and oil content ω1 of the oily wastewater, and the lower limit temperature T2 and oil content ω2 of the oily wastewater; the upper limit is located at the bottom of the weir plate, and the lower limit is located in the middle of the sedimentation chamber; and The controller is used to:

1. When the level of the oily wastewater reaches the lower limit, control the heater 2 to operate at maximum power P. max2 Operation; when the oily wastewater level reaches the upper limit, determine whether T1 is higher than a preset temperature T. e If yes, then control the heater to operate at the minimum power P. min1 Run, otherwise control the heater to operate at maximum power P. max1 run; 2. Determine if T2 is lower than a preset temperature T. e If yes, then control the heater two to operate at maximum power P. max2 Run; otherwise, control the heater two to operate at minimum power P. min2 run; III. Determine whether ω1 is greater than a preset oil content ω e If yes, then the water inlet rate remains constant; otherwise, calculate the ideal water inlet rate v and adjust the water inlet rate to v; the oil content ω e Expressed as: The ideal influent rate v is expressed as: in, This represents the average oil content of the influent during the previous cycle. The inflow rate in the previous cycle. The ideal oil content of the average wastewater during the current cycle; IV. Determine if ω2 is lower than a preset oil content ω n If yes, then control the operation of the sewage pump to discharge all the kitchen oil and water below the lower limit.

2. The slag removal device for oily wastewater according to claim 1, characterized in that, The first heater uses a carbon fiber heating plate with a rated power of 200W; the second heater uses a carbon fiber heating plate with a rated power of 600W.

3. The slag removal device for oily wastewater according to claim 1, characterized in that, The water inlet unit includes a submersible pump and an inlet pipe; the submersible pump is installed in a collection pit for storing oily wastewater; one end of the inlet pipe is connected to the submersible pump, and the other end is connected to the sedimentation chamber.

4. A method for removing sludge from oily wastewater, applied to the sludge removal device for oily wastewater as described in any one of claims 1 to 3, characterized in that, The slag removal method includes: S1: Collect the initial oil content ω0, the upper limit temperature T1, and the oil content ω1 of the oily wastewater, as well as the lower limit temperature T2 and the oil content ω2 of the oily wastewater; the upper limit is set at the bottom of the weir plate of the slag removal device, and the lower limit is set in the middle of the sedimentation chamber of the slag removal device. S2: When the level of the oily wastewater reaches the lower limit, a preset power P is applied. max2 The oily wastewater in the sedimentation chamber is heated; when the liquid level of the oily wastewater reaches the upper limit, it is determined whether T1 is higher than a preset temperature T. e Yes, then according to power P min1 The oily wastewater within the weir plate is heated; otherwise, it is heated according to power P. max1 The oily wastewater within the weir plate is heated; S3: Determine if T2 is lower than a preset temperature T. e Yes, then according to power P max2 The oily wastewater in the deposition chamber is heated; otherwise, the power is controlled according to P. min2 The oily wastewater in the deposition chamber is heated; S4: Determine if ω1 is greater than a preset oil content ω e If yes, then the inflow rate of the oily wastewater is kept constant; otherwise, the ideal inflow rate v of the oily wastewater is calculated, and the oily wastewater is controlled to be introduced into the sedimentation chamber at a rate v; the oil content ω e Expressed as: The ideal influent rate v is expressed as: in, This represents the average oil content of the influent during the previous cycle. The inflow rate in the previous cycle. The ideal oil content of the average wastewater during the current cycle; S5: Determine if ω2 is lower than a preset oil content ω n If yes, then all solid waste and liquid oil and water below the lower limit will be discharged.

5. A three-phase separation device for oily wastewater, characterized in that, The three-phase separation device includes: The slag removal device for oily wastewater as described in any one of claims 1 to 3; An oil-water separator tank, which is connected to a through-hole in the housing of the sludge removal device via a pipe; the oil-water separator tank is used to separate oil and water in oily wastewater by static sedimentation; and A discharge device, which is installed on the oil-water separator, is used to discharge the oil and water inside the oil-water separator.

6. The three-phase separation device for oily wastewater according to claim 5, characterized in that, The discharge device includes a drain pipe, a three-way valve, and an oil drum. One end of the drain pipe is connected to the bottom of the oil-water separator. The three-way valve includes an input end, an oil discharge end, and a drain end. The input end of the three-way valve is connected to the other end of the drain pipe. The oil discharge end of the three-way valve is connected to the oil drum for oil recovery. The drain end of the three-way valve is used for draining water.

7. The three-phase separation device for oily wastewater according to claim 5, characterized in that, The three-phase separation equipment also includes an oil content detector, which is installed at the connection between the oil-water separation tank and the discharge device, and is used to detect the oil content of the oily wastewater at the bottom of the oil-water separation tank.

8. The three-phase separation device for oily wastewater according to claim 5, characterized in that, The three-phase separation equipment also includes a heating device, which is installed on the oil-water separation tank and is used to heat the oily wastewater in the oil-water separation tank.

9. The three-phase separation device for oily wastewater according to claim 5, characterized in that, The three-phase separation equipment also includes a stirring device; the stirring device is installed inside the oil-water separation tank and is used to stir the oily wastewater inside the oil-water separation tank.

10. A method for three-phase separation of oily wastewater, applied to the three-phase separation equipment for oily wastewater as described in any one of claims 5 to 9, characterized in that, The three-phase separation method includes the following process: S10: The oily wastewater is deslag-removed using the slag removal method described in claim 4; S20: Oil-water separation: S201: The liquid phase oil and water in the oil-water separator are heated and stirred; when the temperature of the liquid phase oil and water in the oil-water separator is higher than a preset threshold, heating and stirring are stopped; S202: The liquid phase oil and water are separated into an oil layer and a water layer in the oil-water separator by static sedimentation. S203: Determine the oil content ω of the liquid phase oil and water at the bottom of the oil-water separator. j Is it below a preset oil content ω? n If yes, the liquid phase oil and water will be discharged; otherwise, the liquid phase oil and water will be recycled.

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