Oily wastewater evaporation and concentration treatment equipment and method

Abstract

The invention discloses oily wastewater evaporation and concentration treatment equipment and method.The oily wastewater evaporation and concentration treatment equipment comprises a sewage treatment barrel, a vacuum distillation device, a heat pump circulation system and a backflow circulation structure, the sewage treatment barrel is integrated with a centrifugal filtering mechanism and an oil scraping mechanism, and fine impurity separation and oil-water separation are achieved; the vacuum distillation device is matched with the vacuum generation device through the distillation unit and the condensation unit to complete deep purification; the heat pump circulation system forms closed-loop energy circulation, and distillation heating and condensation cooling are synchronously performed; the reflux circulation structure realizes secondary treatment of residual liquid, the treatment method comprises the steps of centrifugal filtration, oil removal, vacuum distillation, condensation and reflux circulation, the problems of incomplete pretreatment, high energy consumption and insufficient purification of existing equipment are solved, and the equipment has the characteristics of wide adaptability, good purification effect, energy conservation, high efficiency and stable operation; and up-to-standard discharge or recycling of the oily sewage can be realized.

Description

An equipment and method for evaporating and concentrating oily wastewater Technical Field

[0001] This invention belongs to the field of wastewater treatment technology, and particularly relates to an evaporation and concentration treatment device and method for oily wastewater. Background Technology

[0002] Oily wastewater widely originates from industries such as machining, automobile manufacturing, catering services, and petrochemicals. Its composition is complex, containing not only large amounts of floating oil and emulsified oil, but also bulky solid impurities (such as metal fragments and food scraps), aggregated sludge, and soluble pollutants. Direct discharge will cause eutrophication of water bodies and soil pollution. Furthermore, oil and impurities can corrode pipes, clog water treatment facilities, severely damage the ecological environment, and disrupt normal industrial production. Therefore, efficient purification and treatment of oily wastewater has become a key technological requirement in the environmental protection field.

[0003] Currently, oily wastewater treatment technologies mainly include physical methods, chemical methods, biological methods, and combined processes. Among them, physical methods (such as oil separators, flotation devices, and centrifugal filtration) are the most widely used due to their simple operation and low cost, but traditional physical methods have obvious limitations. Chemical methods (such as demulsifier oxidation) can improve treatment efficiency, but they are prone to secondary pollution and have high reagent costs. Biological methods are suitable for low-concentration oily wastewater, but they are sensitive to water quality fluctuations, have long treatment cycles, and are difficult to adapt to high-concentration, complex-component oily wastewater.

[0004] Existing equipment and processes for treating oily wastewater, which primarily rely on physical methods, have the following prominent drawbacks:

[0005] 1. Incomplete oil-water separation and impurity filtration: Traditional oil separators rely on gravity to achieve oil-water separation, which is inefficient (separation time takes several hours) and emulsified oil is difficult to remove; existing centrifugal filtration equipment is mostly open structure, with poor sealing performance of sewage transportation and rotary filtration, which is prone to leakage. At the same time, trace amounts of oil remain in the filtered sewage, affecting the subsequent distillation and purification effect.

[0006] 2. High energy consumption and serious energy waste: In the distillation and condensation process, traditional equipment uses independent electric heating and cooling devices to achieve wastewater distillation and water vapor condensation respectively. The heating and cooling processes are independent of each other, and energy cannot be recovered and utilized, resulting in high energy consumption. In addition, the coordination and control of vacuum environment and heating / cooling is not good, which easily leads to problems such as low distillation efficiency and insufficient condensation.

[0007] 3. Lack of closed-loop recycling mechanism: Most existing equipment is a single-processing process. The residual liquid after distillation still contains oil and impurities that have not been completely separated. Direct discharge will cause pollution. Direct discharge will not meet environmental emission standards. If it is abandoned, it will waste water resources. Summary of the Invention

[0008] The purpose of this invention is to solve the aforementioned technical problems existing in the prior art, and to provide an oily wastewater evaporation and concentration treatment device and method. This invention aims to address the technical problems of incomplete oil-water separation and impurity filtration, high energy consumption and serious energy waste, and the lack of a closed-loop recycling mechanism in existing oily wastewater treatment equipment and methods. The invention provides an oily wastewater treatment device and method that integrates centrifugal filtration, high-efficiency oil removal, energy-saving vacuum distillation and condensation, and closed-loop reflux, achieving deep purification of oily wastewater, efficient energy utilization, and stable and continuous equipment operation, thus meeting the needs of environmental protection discharge and water resource recycling.

[0009] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0010] An oily wastewater evaporation and concentration treatment device, comprising:

[0011] The wastewater treatment tank has an internal cavity for temporarily storing wastewater. The wastewater treatment tank is equipped with a centrifugal filtration mechanism and an oil skimming mechanism. The input end of the centrifugal filtration mechanism is connected to an external wastewater source through a water pump to extract wastewater and filter impurities. The filtered wastewater is discharged into the cavity. The oil skimming mechanism skims the wastewater in the cavity to separate oil from the wastewater.

[0012] The vacuum distillation apparatus includes a distillation unit, a condensation unit, and a vacuum generator. The inlet of the distillation unit is connected to the receiving cavity of the wastewater treatment tank to receive the wastewater to be treated after filtration and oil removal. The distillation unit is used to distill the wastewater to generate water vapor. The inlet of the condensation unit is connected to the outlet of the distillation unit to receive the water vapor and condense it to form reclaimed water. The vacuum generator is connected to the internal cavities of both the distillation unit and the condensation unit to provide a stable vacuum environment for both, ensuring the vacuum distillation and condensation processes.

[0013] The reflux circulation structure has its input end connected to the residual liquid outlet of the distillation unit and its output end connected to the input end of the centrifugal filtration mechanism. It is used to return the residual liquid remaining after vacuum distillation in the distillation unit to the wastewater treatment tank, where it is further processed by the centrifugal filtration mechanism and the oil skimming mechanism before being circulated back into the distillation unit.

[0014] Furthermore, the centrifugal filtration mechanism includes a filter cylinder, a drive motor, a rotating shaft, and a bearing housing. The bearing housing is fixedly installed at the top of the wastewater treatment tank. The rotating shaft is rotatably mounted in the bearing housing via rolling bearings, and the rotating shaft has a hollow structure that runs vertically through the shaft. The filter cylinder is coaxially fixed at the lower end of the rotating shaft and is located inside the receiving cavity. The cylinder wall of the filter cylinder is densely covered with first filter holes for separating impurities in the wastewater. The drive motor is detachably installed at the top of the wastewater treatment tank via a fixed base. The output shaft of the drive motor and the upper end of the rotating shaft are respectively equipped with matching transmission pulleys. The two transmission pulleys are connected by a transmission belt to enable the drive motor to drive the rotating shaft and the filter cylinder to rotate synchronously. The rotating shaft is connected to a wastewater inlet pipe, which passes through the hollow cavity of the rotating shaft. The wastewater inlet pipe and the rotating shaft are sealed together by a sealed bearing. The wastewater inlet pipe is used to transport the wastewater to be filtered into the rotating filter cylinder. The wastewater after centrifugal filtration is discharged into the receiving cavity through the first filter holes.

[0015] Furthermore, the oil scraping mechanism includes an oil scraping motor, an oil suction belt, a scraper, and an oil collection tank. The oil scraping motor is mounted on the outer wall of the sewage treatment tank via a mounting bracket. The output end of the oil scraping motor is connected to a gear. The oil suction belt is sleeved on the gear. The lower section of the oil suction belt is immersed below the sewage surface in the receiving cavity, and the upper section extends horizontally to the outside of the sewage treatment tank. The scraper is mounted on the mounting bracket, and the scraper elastically fits against the outer surface of the oil suction belt to scrape off the oil adsorbed on the surface of the oil suction belt. The opening of the oil collection tank corresponds to the scraper and is used to collect the oil scraped off by the scraper. The bottom of the oil collection tank is provided with an oil drain port for discharging the collected oil.

[0016] Furthermore, the distillation unit includes a distillation tank, the interior of which forms a distillation chamber for containing the liquid to be treated. The inlet of the distillation tank is connected to the receiving chamber of the wastewater treatment tank to receive the liquid to be treated after filtration and oil removal. The bottom of the distillation tank is provided with a residual liquid outlet, which is connected to a centrifugal filtration mechanism. The residual liquid outlet is used to discharge the residual liquid remaining after low-temperature vacuum distillation. The condensation unit includes a condensation tank, the interior of which forms a condensation chamber for containing the condensing medium. The air inlet of the condensation tank is connected to the air outlet of the distillation tank through a gas guide pipe to receive the water vapor generated by the low-temperature vacuum distillation of the distillation unit.

[0017] Furthermore, a foam detection device is installed inside the distillation tank to detect the foam generation status in the liquid to be treated in real time.

[0018] Furthermore, it also includes a heat pump circulation system, which is connected to the distillation unit and the condensation unit to form a closed-loop energy cycle. The distillation unit is equipped with a coil heating device, the input end of which is connected to the heating end of the heat pump circulation system to provide a low-temperature heating source for the distillation unit. This, combined with the vacuum environment provided by the vacuum generator, enables low-temperature vacuum distillation. The condensation unit is equipped with a coil heat exchange structure, the input end of which is connected to the cooling end of the heat pump circulation system to provide a condensation cold source for the condensation unit and accelerate the condensation and liquefaction of water vapor.

[0019] Furthermore, it also includes a pretreatment device, which is used to pre-separate large-volume solid impurities and agglomerated sludge from external sewage sources. The pretreatment device includes a pretreatment separation tank, a stirring separation unit, and a leveling filtration unit. The pretreatment separation tank forms a pretreatment chamber and a sedimentation chamber from top to bottom. The stirring separation unit is detachably installed to the pretreatment separation tank via a first support frame and is located in the pretreatment chamber. The top of the stirring separation unit has an opening for sewage to enter. The leveling filtration unit is assembled in the pretreatment chamber and is located between the stirring separation unit and the sedimentation chamber. The side wall of the sedimentation chamber has a pretreatment outlet, which is connected to the centrifugal filtration mechanism. The bottom of the sedimentation chamber has a drain outlet for discharging settled impurities.

[0020] Furthermore, the mixing and separation unit includes a mixing tank, a mixing motor, a mixing shaft, mixing blades, and a conical guide. The mixing tank is detachably installed on the upper part of the pretreatment chamber via a first support frame. The mixing chamber inside the mixing tank is formed to accommodate the wastewater to be pretreated. It has an opening at the top for wastewater to enter and a guide outlet at the bottom for discharging the wastewater after mixing. The mixing motor is detachably fixed to the top of the mixing tank via a second support frame. The mixing shaft passes vertically through the mixing chamber, and its upper end is coaxially fixed with the output shaft of the mixing motor. The mixing blades are spiral or paddle-shaped structures, evenly distributed along the circumference of the mixing shaft and fixedly mounted on the mixing shaft. A preset gap is reserved between the outer edge of the mixing blades and the inner wall of the mixing tank. The conical guide is coaxially arranged with the mixing shaft and fixedly mounted inside the mixing chamber. The conical guide cooperates with the mixing blades to guide the wastewater to flow downward along the conical surface to break up the aggregated sludge flocs in the wastewater.

[0021] The leveling filter unit includes leveling blades and a filter plate. The leveling blades are coaxially arranged with the stirring shaft and fixedly assembled at the bottom end of the stirring shaft. The filter plate is installed between the pretreatment chamber and the sedimentation chamber. The filter plate is provided with a second filter hole and is used to filter large solid impurities in wastewater.

[0022] A method for treating oily wastewater using an evaporation and concentration treatment device, characterized by comprising the following steps:

[0023] S1. Centrifugal filtration and oil removal

[0024] S1.1 Centrifugal Filtration: The centrifugal filtration mechanism, which pumps the wastewater to be treated to the wastewater treatment tank, drives the rotating shaft and filter cylinder to rotate synchronously through the transmission pulley and transmission belt. The centrifugal force is used to separate the fine impurities in the wastewater through the first filter hole of the filter cylinder into the receiving cavity. The filtered wastewater is temporarily stored in the receiving cavity.

[0025] S1.2 Oil removal treatment: Start the oil scraping motor of the oil scraping mechanism, and drive the oil suction belt to circulate through the gear. The lower section of the oil suction belt is immersed below the sewage surface of the receiving cavity to absorb the oil. When the oil suction belt moves to the upper section after absorbing the oil, the surface oil is scraped off by the scraper that is in contact with the oil suction belt. The scraped oil is collected by the oil collection tank and discharged through the oil outlet.

[0026] S2, Vacuum distillation and condensation:

[0027] S2.1 Low-temperature vacuum distillation: The wastewater treated in step S1 is transported to the distillation chamber of the distillation unit. The heat pump circulation system is started, and its heating end supplies heat to the coil heating device of the distillation unit to heat the wastewater at a low temperature. At the same time, the vacuum generator is started to provide a stable vacuum environment for the distillation chamber and the condensation chamber, so that the wastewater distills under vacuum conditions to produce water vapor. During the distillation process, the foam generation status of the liquid to be treated is detected in real time by the foam detection device, and the defoaming action is triggered as needed.

[0028] S2.2, Condensation to produce reclaimed water: The water vapor produced by distillation is introduced into the condensation chamber of the condensation unit through the gas guide pipe. The refrigeration end of the heat pump cycle system delivers cooling capacity to the coil heat exchange structure of the condensation unit, so that the water vapor is quickly condensed and liquefied in the condensation chamber to form reclaimed water. The reclaimed water is discharged and recycled through the drain structure of the condensation tank.

[0029] S3, Reflux Circulation:

[0030] S3.1 Residual liquid reflux: The residual liquid remaining after low-temperature vacuum distillation in step S2 is discharged from the residual liquid outlet through the reflux circulation structure and returned to the input end of the centrifugal filtration mechanism.

[0031] S3.2 Circulation Treatment: The returned residual liquid is subjected to repeated centrifugal filtration, oil removal, vacuum distillation and condensation treatments in sequence as described in S1-S2 to achieve deep purification of wastewater circulation until the residual liquid meets the preset treatment standards or meets the discharge or recycling requirements.

[0032] Furthermore, it also includes a pretreatment step: the external sewage source is introduced into the stirring and separation unit of the pretreatment device, the stirring motor drives the stirring shaft and stirring blades to rotate, and the conical guide guides the sewage to flow downward along the cone surface, breaking up the aggregated sludge flocs in the sewage. At the same time, the leveling blades at the bottom of the stirring shaft level the sewage flow, so that the sewage flows evenly through the filter plate. The second filter hole of the filter plate intercepts large solid impurities. The filtered sewage enters the sedimentation chamber for settling. The settled impurities are periodically discharged through the sewage outlet at the bottom of the sedimentation chamber. The pretreated sewage is discharged from the pretreated liquid outlet on the side wall of the sedimentation chamber to the centrifugal filtration mechanism.

[0033] The present invention, by adopting the above-described technical solution, has the following beneficial effects:

[0034] 1. This invention constructs a fully closed-loop treatment process consisting of pretreatment, centrifugal filtration, high-efficiency oil removal, vacuum distillation and condensation, and reflux circulation. In the pretreatment stage, the agglomerated sludge is broken up by a stirring and separation unit, and large-volume impurities are thoroughly separated by spreading filtration and sedimentation. In the core treatment stage, fine impurities are separated by centrifugal filtration, oil is efficiently removed by an oil skimming mechanism, and deep purification of wastewater is achieved by vacuum distillation and condensation. Reflux circulation allows for repeated treatment of residual liquid, and the quality of reclaimed water can meet industrial reuse or discharge standards, solving the problem of incomplete single-stage treatment in traditional equipment.

[0035] 2. This invention uses a heat pump circulation system to form a closed-loop energy circuit with the distillation unit and the condensation unit. The heating end of the heat pump circulation system provides a low-temperature heating heat source for the distillation unit, and the cooling end provides a condensation cold source for the condensation unit. Energy is internally recovered and reused. Compared with traditional independent heating and cooling equipment, energy consumption is significantly reduced and energy utilization efficiency is improved, which meets the national requirements for energy conservation and low carbon development.

[0036] 3. This invention modularly integrates the pretreatment device, sewage treatment tank, vacuum distillation device and reflux circulation structure, with each unit tightly connected, reducing the floor space occupied; the filter cylinder, scraper, stirring blade, conical guide body and other components are all designed for detachable installation, and through structural optimization such as sealed bearings, preset gaps and foam detection, problems such as blockage, leakage and foam interference during equipment operation are avoided, resulting in strong operational stability and convenient maintenance.

[0037] 4. The centrifugal filtration mechanism of this invention adopts a hollow rotating shaft and a filter cylinder with densely packed first filter holes, and works with a sealed bearing to achieve stable sewage transport in the rotating state. Under the action of centrifugal force, fine impurities are completely separated. The oil scraping mechanism integrates oil adsorption, scraping and collection through an oil suction belt, scraper and oil collection tank. It has high oil-water separation efficiency and convenient oil recovery, which can realize resource reuse. Attached Figure Description

[0038] The present invention will be further described below with reference to the accompanying drawings:

[0039] Figure 1 is a schematic diagram of the structure of an embodiment of the oily wastewater evaporation and concentration treatment equipment of the present invention.

[0040] Figure 2 is a schematic diagram of the structure of the sewage treatment tank in this invention.

[0041] Figure 3 is a schematic diagram of the centrifugal filtration mechanism in this invention.

[0042] Figure 4 is a cross-sectional view of the centrifugal filtration mechanism in this invention.

[0043] Figure 5 is a schematic diagram of the oil scraping mechanism in this invention.

[0044] Figure 6 is a schematic diagram of the vacuum distillation apparatus in this invention.

[0045] Figure 7 is a top view of the vacuum distillation apparatus of the present invention.

[0046] Figure 8 is a schematic diagram of the structure of a second embodiment of the oily wastewater evaporation and concentration treatment equipment of the present invention.

[0047] Figure 9 is a schematic diagram of the pretreatment device in Embodiment 2 of the present invention.

[0048] Figure 10 is a schematic diagram of the structure of the stirring separation unit and the flattening filtration unit in Embodiment 2 of the present invention.

[0049] Figure 11 is a cross-sectional view of Figure 10 in Embodiment 2 of the present invention.

[0050] In the diagram: 1-Sewage treatment tank; 11-Containing cavity; 12-Centrifugal filtration mechanism; 121-Filter cylinder; 122-Drive motor; 123-Rotating shaft; 124-Bearing seat; 125-Rolling bearing; 126-First filter hole; 127-Fixed seat; 128-Transmission pulley; 129-Sewage inlet pipe; 1210-Sealed bearing; 13-Oil scraping mechanism; 131-Oil scraping motor; 132-Oil suction belt; 133-Oil collection tank; 134-Mounting bracket; 135-Gear; 136-Oil outlet;

[0051] 2-Vacuum distillation apparatus; 21-Distillation unit; 211-Distillation barrel; 212-Distillation chamber; 213-Liquid inlet; 214-Coil heating device; 22-Condensation unit; 221-Condensation barrel; 222-Condensation chamber; 223-Gas inlet; 224-Coil heat exchange structure; 23-Vacuum generator;

[0052] 3-Pretreatment device; 31-Pretreatment separation tank; 311-Pretreatment chamber; 312-Sedimentation chamber; 313-Pretreatment outlet; 314-Drainage outlet; 315-First support frame; 32-Stirring separation unit; 321-Stirring tank; 3211-Stirring chamber; 3212-Opening; 3213-Guide outlet; 322-Stirring motor; 323-Stirring shaft; 324-Stirring blades; 325-Conical guide body; 326-Second support frame; 33-Flattening filtration unit; 331-Flattening blades; 332-Filter plate; 333-Second filter hole. Detailed Implementation

[0053] Example 1

[0054] As shown in Figures 1 to 7, this embodiment provides an oily wastewater evaporation and concentration treatment device, including a wastewater treatment tank 1, a vacuum distillation device 2, a heat pump circulation system and a reflux circulation structure, with each unit connected and cooperating to achieve wastewater purification.

[0055] The sewage treatment tank 1 has an internal cavity 11 for temporarily storing sewage, and is equipped with a centrifugal filtration mechanism 12 and an oil skimming mechanism 13.

[0056] The input end of the centrifugal filtration mechanism 12 is connected to an external sewage source via a water pump for extracting sewage and filtering impurities. The centrifugal filtration mechanism 12 includes a filter cylinder 121, a drive motor 122, a rotating shaft 123, and a bearing seat 124. The bearing seat 124 is fixedly installed at the top of the sewage treatment tank 1. The rotating shaft 123 is rotatably mounted in the bearing seat 124 via a rolling bearing 125, and the rotating shaft 123 is a hollow structure that runs vertically through the shaft. The filter cylinder 121 is coaxially fixed to the lower end of the rotating shaft 123 and is located inside the receiving cavity 11. The cylinder wall of the filter cylinder 121 is densely covered with first filter holes 126 for separating impurities in the sewage. The drive motor 122 is detachably installed via a fixing seat 127. At the top of the wastewater treatment tank 1, the output shaft of the drive motor 122 and the upper end of the rotating shaft 123 are respectively equipped with matching transmission pulleys 128. The two transmission pulleys 128 are connected by a transmission belt to enable the drive motor 122 to drive the rotating shaft 123 and the filter cylinder 121 to rotate synchronously. The rotating shaft 123 is connected to a wastewater inlet pipe 129, which passes through the hollow cavity of the rotating shaft 123. The wastewater inlet pipe 129 and the rotating shaft 123 are sealed together by a sealed bearing 1210. The wastewater inlet pipe 129 is used to transport the wastewater to be filtered into the rotating filter cylinder 121. After centrifugal filtration, the wastewater is discharged into the receiving cavity 11 through the first filter hole 126.

[0057] The oil scraping mechanism 13 scrapes the sewage in the receiving cavity 11 to separate the oil from the sewage. The oil scraping mechanism 13 includes an oil scraping motor 131, an oil suction belt 132, a scraper, and an oil collection tank 133. The oil scraping motor 131 is mounted on the outer wall of the sewage treatment tank 1 via a mounting bracket 134. A gear 135 is connected to the output end of the oil scraping motor 131. The oil suction belt 132 is sleeved on the gear 135, and the lower section of the oil suction belt 132 is immersed in the sewage surface of the receiving cavity 11. The upper section extends horizontally to the outside of the sewage treatment tank 1. The oil-absorbing belt 132 can be made of an oleophilic and hydrophobic material. The scraper is mounted on the mounting bracket 134 and elastically fits the outer surface of the oil-absorbing belt 132 to scrape off the oil adsorbed on the surface of the oil-absorbing belt 132. The opening 3212 of the oil collection tank 133 corresponds to the scraper and is used to collect the oil scraped off by the scraper. The bottom of the oil collection tank 133 is provided with an oil drain port 136 for discharging the collected oil.

[0058] The vacuum distillation apparatus 2 includes a distillation unit 21, a condensation unit 22, and a vacuum generator 23, and is used to deeply purify wastewater after it has been filtered and degreased.

[0059] The inlet of the distillation unit 21 is connected to the receiving cavity 11 of the wastewater treatment tank 1, and is used to receive the wastewater to be treated after filtration and oil removal. The distillation unit 21 is used to distill the wastewater to generate water vapor. The distillation unit 21 includes a distillation tank 211. The interior of the distillation tank 211 forms a distillation cavity 212 for containing the liquid to be treated. The inlet 213 of the distillation tank 211 is connected to the receiving cavity 11 of the wastewater treatment tank 1, and is used to receive the liquid to be treated after filtration and oil removal. The bottom of the distillation tank 211 is provided with a residual liquid outlet, which is connected to the centrifugal filtration mechanism 12 through a reflux circulation structure. The residual liquid outlet is used to discharge the residual liquid remaining after low-temperature vacuum distillation. The distillation tank 211 is provided with a foam detection device, such as an optical foam sensor, which is used to detect the foam generation status in the liquid to be treated in real time.

[0060] The inlet end 223 of the condensing unit 22 is connected to the outlet end of the distillation unit 21 to receive water vapor and condense it to form regenerated water. The condensing unit 22 includes a condensing tank 221. The interior of the condensing tank 221 forms a condensing chamber 222 for containing the condensing medium. The inlet end 223 of the condensing tank 221 is connected to the outlet end of the distillation tank 211 through a gas guide pipe to receive water vapor generated by the distillation unit 21 through low-temperature vacuum distillation.

[0061] The vacuum generating device 23 is connected to the internal cavities of the distillation unit 21 and the condensation unit 22 respectively. The vacuum generating device 23 can be a Venturi vacuum generator, which is connected to the distillation chamber 212 and the condensation chamber 222 respectively through pipelines to provide a stable vacuum environment of -0.096KPa for both, ensuring the vacuum distillation and condensation processes.

[0062] The heat pump cycle system (not shown in the figure) is connected to the distillation unit 21 and the condensation unit 22 to form a closed-loop energy cycle. The distillation unit 21 is equipped with a coil heating device 214, the input end of which is connected to the heating end of the heat pump cycle system to provide a low-temperature heating source for the distillation unit 21. This, together with the vacuum environment provided by the vacuum generator 23, enables low-temperature vacuum distillation. The condensation unit 22 is equipped with a coil heat exchange structure 224, the input end of which is connected to the cooling end of the heat pump cycle system to provide a condensation cold source for the condensation unit 22 and accelerate the condensation and liquefaction of water vapor.

[0063] The input end of the reflux circulation structure (not shown in the figure) is connected to the residual liquid outlet of the distillation unit 21, and the output end is connected to the input end of the centrifugal filtration mechanism 12. It is used to return the residual liquid remaining after vacuum distillation of the distillation unit 21 to the sewage treatment tank 1, and after being processed again by the centrifugal filtration mechanism 12 and the oil skimming mechanism 13, it is circulated back into the distillation unit 21.

[0064] Based on the above-mentioned equipment, the present invention provides a treatment method for oily wastewater evaporation and concentration treatment equipment, comprising the following steps:

[0065] S1. Centrifugal filtration and oil removal

[0066] S1.1 Centrifugal filtration: The wastewater to be treated is pumped by a water pump and transported to the centrifugal filtration mechanism 12 of the sewage treatment tank 1. The drive motor 122 drives the rotating shaft 123 and the filter cylinder 121 to rotate synchronously through the transmission pulley 128 and the transmission belt. The centrifugal force is used to separate the fine impurities in the sewage through the first filter hole 126 of the filter cylinder 121 into the receiving cavity 11. The filtered sewage is temporarily stored in the receiving cavity 11.

[0067] S1.2 Oil removal treatment: Start the oil scraping motor 131 of the oil scraping mechanism 13, and drive the oil suction belt 132 to rotate in a cycle through the gear 135. The lower section of the oil suction belt 132 is immersed below the sewage liquid surface of the receiving cavity 11 to absorb oil. When the oil suction belt 132 rotates to the upper section after absorbing oil, the surface oil is scraped off by the scraper that is in contact with the oil suction belt 132. The scraped oil is collected by the oil collection tank 133 and discharged through the oil outlet 136.

[0068] S2, Vacuum distillation and condensation:

[0069] S2.1 Low-temperature vacuum distillation: The wastewater treated in step S1 is transported to the distillation chamber 212 of the distillation unit 21. The heat pump circulation system is started, and its heating end supplies heat to the coil heating device 214 of the distillation unit 21 to heat the wastewater at low temperature. At the same time, the vacuum generator 23 is started to provide a stable vacuum environment for the distillation chamber 212 and the condensation chamber 222, so that the wastewater distills under vacuum conditions to generate water vapor. During the distillation process, the foam generation status of the liquid to be treated is detected in real time by the foam detection device, and the defoaming action is triggered as needed.

[0070] S2.2, Condensation to produce reclaimed water: The water vapor generated by distillation is introduced into the condensation chamber 222 of the condensation unit 22 through the gas guide pipe. The cooling end of the heat pump cycle system delivers cooling capacity to the coil heat exchange structure 224 of the condensation unit 22, so that the water vapor is quickly condensed and liquefied in the condensation chamber 222 to form reclaimed water. The reclaimed water is discharged and recycled through the drain structure of the condensation tank 221.

[0071] S3, Reflux Circulation:

[0072] S3.1 Residual liquid reflux: The residual liquid remaining after low-temperature vacuum distillation in distillation unit 21 in step S2 is discharged from the residual liquid outlet through the reflux circulation structure and returned to the input end of centrifugal filtration mechanism 12.

[0073] S3.2 Circulation Treatment: The returned residual liquid is subjected to repeated centrifugal filtration, oil removal, vacuum distillation and condensation treatments in sequence as described in S1-S2 to achieve deep purification of wastewater circulation until the residual liquid meets the preset treatment standards or meets the discharge or recycling requirements.

[0074] Example 2

[0075] As shown in Figures 8 to 11, this embodiment is based on the structure of Embodiment 1, and a pretreatment device 3 is added to address the large volume solid impurities and agglomerated sludge in the wastewater. The rest of the structure is completely consistent with Embodiment 1.

[0076] The pretreatment device 3 is used to pre-separate large-volume solid impurities and agglomerated sludge from external sewage sources, and includes a pretreatment separation tank 31, a stirring separation unit 32, and a leveling filtration unit 33.

[0077] The pretreatment separation tank 31 forms a pretreatment chamber 311 and a sedimentation chamber 312 from top to bottom. The sedimentation chamber 312 has a pretreatment outlet 313 on its side wall, which is connected to the centrifugal filtration mechanism 12. The bottom of the sedimentation chamber 312 has a drain outlet 314, which is used to discharge settled impurities.

[0078] The stirring and separating unit 32 is detachably installed on the pretreatment separation tank 31 via the first support frame 315 and located in the pretreatment chamber 311. The stirring and separating unit 32 has an opening 3212 at the top for sewage to enter. It includes a stirring tank 321, a stirring motor 322, a stirring shaft 323, stirring blades 324, and a conical guide body 325. The stirring tank 321 is detachably installed on the upper part of the pretreatment chamber 311 via the first support frame 315. The stirring tank 321 forms a stirring chamber 3211 inside to accommodate the sewage to be pretreated. It has an opening 3212 at the top for sewage to enter and a guide outlet 3213 at the bottom for discharging the sewage after stirring. The stirring motor 322 is connected to the second support frame 315. The support frame 326 is detachably fixed to the top of the mixing tank 321. The mixing shaft 323 is vertically inserted into the mixing chamber 3211, and its upper end is coaxially fixed to the output shaft of the mixing motor 322. The mixing blades 324 are spiral or paddle-shaped structures, evenly distributed around the mixing shaft 323 and fixedly mounted on the mixing shaft 323. A preset gap is reserved between the outer edge of the mixing blades 324 and the inner wall of the mixing tank 321. The conical guide body 325 is coaxially arranged with the mixing shaft 323 and fixedly mounted inside the mixing chamber 3211. The conical guide body 325 cooperates with the mixing blades 324 to guide the sewage to flow downward along the conical surface to break up the aggregated sludge flocs in the sewage.

[0079] The leveling filter unit 33 is assembled in the pretreatment chamber 311, located between the stirring separation unit 32 and the sedimentation chamber 312. It includes leveling blades 331 and filter plates 332. The leveling blades 331 are coaxially arranged with the stirring shaft 323 and are fixedly assembled at the bottom end of the stirring shaft 323. The filter plates 332 are installed between the pretreatment chamber 311 and the sedimentation chamber 312. The filter plates 332 are provided with second filter holes 333. The filter plates 332 are used to filter large solid impurities in wastewater.

[0080] Based on the processing method described in Example 1, a preprocessing step is added. The remaining steps are completely consistent with those in Example 1. The preprocessing step is as follows:

[0081] External sewage is introduced into the stirring and separation unit 32 of the pretreatment device 3. The stirring motor 322 drives the stirring shaft 323 and stirring blades 324 to rotate. The conical guide body 325 guides the sewage to flow downward along the conical surface, breaking up the aggregated sludge flocs in the sewage. At the same time, the leveling blades 331 at the bottom of the stirring shaft 323 level the sewage flow, so that the sewage flows evenly through the filter plate 332. The second filter hole 333 of the filter plate 332 intercepts large solid impurities. The filtered sewage enters the sedimentation chamber 312 for sedimentation. The sedimented impurities are periodically discharged through the sewage outlet 314 at the bottom of the sedimentation chamber 312. The pretreated sewage is discharged from the pretreated liquid outlet 313 on the side wall of the sedimentation chamber 312 to the centrifugal filtration mechanism 12. The S1-S3 steps described in Example 1 are then executed sequentially.

[0082] The above are merely specific embodiments of the present invention, but the technical features of the present invention are not limited thereto. Any simple changes, equivalent substitutions, or modifications made based on the present invention to solve essentially the same technical problems and achieve essentially the same technical effects are all covered within the protection scope of the present invention.

Claims

1. An evaporation and concentration treatment device for oily wastewater, characterized in that: The system includes a wastewater treatment tank with an internal cavity for temporarily storing wastewater. A centrifugal filtration mechanism and an oil skimming mechanism are integrated into the tank. The input of the centrifugal filtration mechanism is connected to an external wastewater source via a water pump to extract wastewater and filter impurities. The filtered wastewater is discharged into the cavity. The oil skimming mechanism skims the wastewater from the cavity to separate oil from the wastewater. A vacuum distillation device is also included, comprising a distillation unit, a condensation unit, and a vacuum generator. The inlet of the distillation unit is connected to the cavity of the wastewater treatment tank to receive the filtered and oil-removed wastewater. The distillation unit is used to process the wastewater... Distillation produces water vapor. The inlet of the condensation unit is connected to the outlet of the distillation unit to receive the water vapor and condense it into regenerated water. The vacuum generator is connected to the internal cavities of both the distillation unit and the condensation unit to provide a stable vacuum environment for both, ensuring the vacuum distillation and condensation processes. A reflux circulation structure is provided, with its input connected to the residual liquid outlet of the distillation unit and its output connected to the input of the centrifugal filtration mechanism. This structure returns the residual liquid remaining after vacuum distillation to the wastewater treatment tank, where it is further processed by the centrifugal filtration mechanism and the oil skimming mechanism before being circulated back into the distillation unit.

2. The oily wastewater evaporation and concentration treatment equipment according to claim 1, characterized in that: The centrifugal filtration mechanism includes a filter cylinder, a drive motor, a rotating shaft, and a bearing housing. The bearing housing is fixedly installed at the top of the wastewater treatment tank. The rotating shaft is rotatably mounted in the bearing housing via rolling bearings and has a hollow structure that extends vertically. The filter cylinder is coaxially fixed to the lower end of the rotating shaft and is located within the receiving cavity. The filter cylinder wall is densely covered with first filter holes for separating impurities from the wastewater. The drive motor is detachably installed at the top of the wastewater treatment tank via a fixed base. The output shaft of the drive motor and the upper end of the rotating shaft are respectively equipped with matching transmission pulleys. The two transmission pulleys are connected by a transmission belt to enable the drive motor to drive the rotating shaft and the filter cylinder to rotate synchronously. The rotating shaft is connected to a wastewater inlet pipe, which passes through the hollow cavity of the rotating shaft and is sealed to the rotating shaft via a sealing bearing. The wastewater inlet pipe is used to deliver wastewater to be filtered into the rotating filter cylinder. The wastewater after centrifugal filtration is discharged into the receiving cavity through the first filter holes.

3. The oily wastewater evaporation and concentration treatment equipment according to claim 1, characterized in that: The oil scraping mechanism includes an oil scraping motor, an oil suction belt, a scraper, and an oil collection tank. The oil scraping motor is mounted on the outer wall of the sewage treatment tank via a mounting bracket. The output end of the oil scraping motor is connected to a gear. The oil suction belt is sleeved on the gear. The lower section of the oil suction belt is immersed below the sewage surface in the receiving cavity, and the upper section extends horizontally to the outside of the sewage treatment tank. The scraper is mounted on the mounting bracket and elastically fits against the outer surface of the oil suction belt to scrape off the oil adsorbed on the surface of the oil suction belt. The opening of the oil collection tank corresponds to the scraper and is used to collect the oil scraped off by the scraper. The bottom of the oil collection tank is provided with an oil drain port for discharging the collected oil.

4. The oily wastewater evaporation and concentration treatment equipment according to claim 1, characterized in that: The distillation unit includes a distillation tank, the interior of which forms a distillation chamber for containing the liquid to be treated. The inlet of the distillation tank is connected to the receiving chamber of the wastewater treatment tank for receiving the liquid to be treated after filtration and oil removal. The bottom of the distillation tank is provided with a residual liquid outlet, which is connected to the centrifugal filtration mechanism for discharging the residual liquid remaining after low-temperature vacuum distillation. The condensation unit includes a condensation tank, the interior of which forms a condensation chamber for containing a condensing medium. The inlet of the condensation tank is connected to the outlet of the distillation tank through a gas guide pipe for receiving water vapor generated by the low-temperature vacuum distillation of the distillation unit.

5. The oily wastewater evaporation and concentration treatment equipment according to claim 4, characterized in that: The distillation tank is equipped with a foam detection device, which is used to detect the foam generation status in the liquid to be treated in real time.

6. The oily wastewater evaporation and concentration treatment equipment according to claim 1, characterized in that: It also includes a heat pump circulation system, which is connected to the distillation unit and the condensation unit to form a closed-loop energy cycle. The distillation unit is equipped with a coil heating device, the input end of which is connected to the heating end of the heat pump circulation system to provide a low-temperature heating source for the distillation unit. This, combined with the vacuum environment provided by the vacuum generator, enables low-temperature vacuum distillation. The condensation unit is equipped with a coil heat exchange structure, the input end of which is connected to the cooling end of the heat pump circulation system to provide a condensation cold source for the condensation unit and accelerate the condensation and liquefaction of water vapor.

7. The oily wastewater evaporation and concentration treatment equipment according to claim 1, characterized in that: It also includes a pretreatment device for pre-separating large-volume solid impurities and agglomerated sludge from external sewage sources. The pretreatment device includes a pretreatment separation tank, a stirring separation unit, and a leveling filtration unit. The pretreatment separation tank forms a pretreatment chamber and a sedimentation chamber from top to bottom. The stirring separation unit is detachably installed to the pretreatment separation tank via a first support frame and is located in the pretreatment chamber. The top of the stirring separation unit has an opening for sewage to enter. The leveling filtration unit is assembled in the pretreatment chamber and located between the stirring separation unit and the sedimentation chamber. The side wall of the sedimentation chamber has a pretreatment outlet that communicates with the centrifugal filtration mechanism. The bottom of the sedimentation chamber has a drain outlet for discharging settled impurities.

8. The oily wastewater evaporation and concentration treatment equipment according to claim 7, characterized in that: The mixing and separation unit includes a mixing tank, a mixing motor, a mixing shaft, mixing blades, and a conical guide. The mixing tank is detachably mounted on the upper part of the pretreatment chamber via a first support frame. The mixing tank forms a mixing chamber to accommodate the wastewater to be pretreated. It has an opening at the top for wastewater to enter and a guide outlet at the bottom for discharging the treated wastewater. The mixing motor is detachably fixed to the top of the mixing tank via a second support frame. The mixing shaft extends vertically through the mixing chamber, with its upper end coaxially fixed to the output shaft of the mixing motor. The mixing blades are spiral or paddle-shaped, evenly distributed along the circumference of the mixing shaft, and fixedly assembled to the mixing tank. On the stirring shaft, a preset gap is reserved between the outer edge of the stirring blade and the inner side wall of the stirring tank. The conical guide body is coaxially arranged with the stirring shaft and fixedly assembled inside the stirring chamber. The conical guide body cooperates with the stirring blade and guides the sewage to flow downward along the conical surface to disperse the aggregated sludge flocs in the sewage. The leveling filter unit includes leveling blades and a filter plate. The leveling blades are coaxially arranged with the stirring shaft and fixedly assembled at the bottom end of the stirring shaft. The filter plate is installed between the pretreatment chamber and the sedimentation chamber. The filter plate is provided with a second filter hole. The filter plate is used to filter large solid impurities in the sewage.

9. A treatment method for oily wastewater evaporation and concentration equipment according to any one of claims 1-8, characterized in that... Includes the following steps: S1. Centrifugal Filtration and Oil Removal: S1.

1. Centrifugal Filtration: Wastewater to be treated is pumped to the centrifugal filtration mechanism of the wastewater treatment tank by a water pump. The drive motor drives the rotating shaft and filter cylinder to rotate synchronously through the transmission pulley and transmission belt. Centrifugal force is used to separate fine impurities in the wastewater through the first filter hole of the filter cylinder into the receiving cavity. The filtered wastewater is temporarily stored in the receiving cavity. S1.

2. Oil Removal: The oil scraping motor of the oil scraping mechanism is started. The oil suction belt is driven by gears to circulate. The lower section of the oil suction belt is immersed below the surface of the wastewater in the receiving cavity to absorb oil. When the oil suction belt moves to the upper section, the surface oil is scraped off by the scraper that is in contact with the oil suction belt. The scraped oil is collected by the oil collection tank and discharged through the oil outlet. S2. Vacuum Distillation and Condensation: S2.

1. Low-Temperature Vacuum Distillation: The wastewater treated in step S1 is transported to the distillation chamber of the distillation unit. The heat pump circulation system is started. Its heating end transfers heat to the coil heating device of the distillation unit to heat the wastewater at a low temperature. At the same time, the vacuum distillation system is started. The air generator provides a stable vacuum environment for the distillation and condensation chambers, allowing wastewater to distill and generate water vapor under vacuum conditions. During distillation, a foam detection device monitors the foam generation status of the liquid to be treated in real time and triggers defoaming actions as needed. S2.2, Condensation to produce reclaimed water: The water vapor generated by distillation is introduced into the condensation chamber of the condensation unit through a gas guide pipe. The cooling end of the heat pump circulation system delivers cooling capacity to the coil-type heat exchange structure of the condensation unit, causing the water vapor to quickly condense and liquefy in the condensation chamber to form reclaimed water. The reclaimed water is discharged and recycled through the drain structure of the condensation tank. S3, Recirculation: S3.1, Residual liquid recirculation: The residual liquid remaining after low-temperature vacuum distillation in step S2 is discharged from the residual liquid outlet through the recirculation structure and returned to the input end of the centrifugal filtration mechanism. S3.2, Circulation treatment: The returned residual liquid is repeatedly subjected to centrifugal filtration and oil removal, vacuum distillation and condensation treatment in sequence as S1-S2 to achieve deep purification of wastewater circulation until the residual liquid meets the preset treatment standards or meets the discharge or recycling requirements.

10. The treatment method of an oily wastewater evaporation and concentration treatment device according to claim 9, characterized in that: It also includes a pretreatment step: the external sewage source is introduced into the stirring and separation unit of the pretreatment device, the stirring motor drives the stirring shaft and stirring blades to rotate, and the conical guide guides the sewage to flow downward along the cone surface, breaking up the aggregated sludge flocs in the sewage. At the same time, the leveling blades at the bottom of the stirring shaft level the sewage flow, so that the sewage flows evenly through the filter plate. The second filter hole of the filter plate intercepts large solid impurities. The filtered sewage enters the sedimentation chamber for settling. The settled impurities are periodically discharged through the sewage outlet at the bottom of the sedimentation chamber. The pretreated sewage is discharged from the pretreated liquid outlet on the side wall of the sedimentation chamber to the centrifugal filtration mechanism.

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