A wastewater treatment system and method for the production of Damascus rose essential oil

Abstract

A wastewater treatment system and method for the production of Damascus rose essential oil according to the present invention extracts plant pigments from the wastewater after the production of essential oil, which not only generates economic benefits but also solves the problem of wastewater treatment. At the same time, the wastewater treatment system and method of the present invention can achieve the complete extraction and recovery of plant pigments in colored wastewater, and the recycling of ethanol and hydrochloric acid used in the recovery process greatly reduces environmental pollution and the cost of production raw materials.

Description

Technical Field

[0001] The present invention relates to the recovery and utilization of wastewater in the rose processing technology, and particularly to a wastewater treatment system and method after the production of Damascus rose essential oil. Background Art

[0002] After the extraction of Damascus rose essential oil by steam distillation method, a large number of by-products will be produced, including rose wastewater and residues. Generally, the residues remaining after the extraction of rose essential oil contain crude protein, crude fiber, starch and glucose, and also contain various vitamins such as carotene and various macro and micro mineral elements. After special treatment, it can be added to chicken feed to replace a part of conventional feed. The addition of rose pollen in chicken feed can increase the egg production. In addition, the addition of rose leaf powder and 45% rose pollen in meat pig feed can increase the daily weight gain and reduce the feed consumption. It is found that rose flower pigment is a water-soluble flavonoid compound. In addition to this component in the wastewater, there are also impurities such as polysaccharides, pectin and proteins, which are factors affecting the pigment quality.

[0003] Traditionally, after the extraction of Damascus rose essential oil, the wastewater will be treated and no longer recycled. The production process of rose essential oil is a discontinuous production. The production reaction kettle needs to be cleaned frequently, which will produce a large amount of colored wastewater, belonging to high-concentration and difficult-to-degrade wastewater, and the wastewater contains a large amount of water-soluble pigments. At present, the industry urgently needs to provide complete equipment and methods for the recycling of Damascus rose wastewater to solve the problems of wastewater waste and pollution. And the research and development of the recycling of Damascus rose wastewater has important social and economic benefits. Summary of the Invention

[0004] Aiming at the above-mentioned existing technical problems, the purpose of the present invention is to provide a wastewater treatment system and method after the production of Damascus rose essential oil, which extracts the plant pigments in Damascus rose from the wastewater after essential oil production, which is not only economically beneficial, but also solves the problem of wastewater treatment. At the same time, the wastewater treatment system and method of the present invention can realize the complete extraction and recovery of plant pigments in colored wastewater, and the recycling of ethanol and hydrochloric acid used in the recovery process greatly reduces environmental pollution and production raw material costs.

[0005] On the one hand, the present invention provides a wastewater treatment system after the production of Damascus rose essential oil, including: an air flotation separation unit, a flower residue filtration unit, a wastewater vacuum distillation concentration unit, an ethanol purification unit, a first primary mixer, a centrifuge separator, an ethanol recovery unit, a concentrated hydrochloric acid acidolysis unit, a second primary mixer, a second secondary mixer, a filter separator, a hydrochloric acid solution recovery unit and a hydrochloric acid solution concentration unit, which are sequentially connected by pipelines along the flow direction of the colored wastewater;

[0006] The solid substances separated by the centrifugal separator enter the memory. The ethanol vapor of the ethanol recovery unit flows into the ethanol memory and is supplied to the extraction process of the ethanol purification unit. The bottom of the air flotation separation unit is provided with a filtering and blowing plate having a large number of air outlets. The filtering and blowing plate has a hollow inner cavity for air circulation, and the hollow inner cavity is communicated with the air conveying unit;

[0007] The recovered concentrated hydrochloric acid with a concentration ≥95% recovered and concentrated by the hydrochloric acid solution recovery unit and the hydrochloric acid solution concentration unit flows into the concentrated hydrochloric acid memory and is supplied to the plant pigment extraction process of the concentrated hydrochloric acid acidolysis unit; the solid plant pigment substances separated by the filtering separator are collected and utilized through the bottom outlet;

[0008] The first primary mixer and the second primary mixer have the same structure and are both straight pipe mixers, which are composed of a pipe shell and mixing components arranged in the pipe shell; the mixing components are composed of a plurality of panels twisted at an angle of 25° to 55° continuously combined front and back; the length of the panel is h2, the width is w2, and h2 = 1.5 to 2.2w2;

[0009] The second secondary mixer is a zigzag pipe structure, which is composed of an alternating connection of a straight pipe part and a curved pipe part, and both the starting end and the ending end are straight pipe parts; the inside of the curved pipe part has a plurality of convex lip units, the convex lip units are evenly spaced along the length direction of the curved pipe part, and the three surfaces of the convex lip unit facing the inner cavity of the curved pipe part are all trapezoidal surfaces, so that the inner surface of the curved pipe part forms a corrugated shape; the bending radian of the curved pipe part is 165° to 180°, the outer diameter length of the curved pipe part is 0.3 to 0.5 times the length of the straight pipe part, and the pipe diameters of the curved pipe part and the straight pipe part are the same.

[0010] In the present invention, the mixing components continuously mix the fluid by repeatedly dividing, turning, and recombining the fluid flow passing through the pipeline, so that the plant pigment in the wastewater is fully precipitated.

[0011] In the present invention, the ethanol purification unit separates and recovers impurities such as polysaccharides, pectins, and proteins in the colored wastewater by high-purity ethanol.

[0012] In the present invention, the colored wastewater is acidolyzed by high-concentration hydrochloric acid in the concentrated hydrochloric acid acidolysis unit, and further fully mixed by the second primary mixer and the second secondary mixer, so that the plant pigment in the colored wastewater is completely precipitated and then separated and recovered.

[0013] In the present invention, the wastewater treatment system also realizes the final recovery and concentration of ethanol and hydrochloric acid for recycling, further reducing environmental pollution and raw material production costs.

[0014] Furthermore, in the wastewater treatment system described in the present invention, the flower residue filtering unit is divided into a filter chamber, a wastewater collection chamber and a flower residue collection chamber by a Y-shaped baffle, the filter chamber corresponds to the wastewater outlet of the air flotation separation unit, and the Y-shaped baffle includes a first filter plate, a second solid baffle and a first solid baffle; only one edge of the first filter plate is fixedly connected to the second solid baffle and the first solid baffle, and the remaining edges of the first filter plate are sealed and fixedly connected to the outer wall of the flower residue filtering unit; the upper end edge of the second solid baffle is set as a blind end.

[0015] Furthermore, in the wastewater treatment system of the present invention, the interior of the filter separator is divided into a first sedimentation tank and a second sedimentation tank by a first partition, a second filter plate is fixedly arranged on one side of the second sedimentation tank close to the liquid outlet, a second partition plate parallel to the first partition plate is vertically arranged at one end of the second filter plate; a third solid baffle plate is arranged parallel to and above the second filter plate, and the third solid baffle plate is not in contact with the second partition plate;

[0016] The first partition includes an upper partition and a lower partition, the lower partition is a solid plate for blocking sediments, the upper partition is a microfiltration membrane partition, and the second filter plate is a microfiltration membrane partition.

[0017] In the present invention, the types of microfiltration membranes mainly include mixed fiber microporous membranes, polypropylene membranes, polyethersulfone membranes, polyvinylidene fluoride membranes, polytetrafluoroethylene membranes and nylon membranes.

[0018] In the present invention, the upper partition and the second filter plate intercept the precipitated solid plant pigment and only allow the liquid to pass through, so that the solid plant pigment is precipitated to the bottom of the filter separator, and then the solid plant pigment is recycled. Through the ingenious design of the partition in the filter separator, the filter separator can achieve precise filtration and complete recovery of the solid plant pigment.

[0019] In the present invention, the design of the third solid baffle can speed up the flow rate of the fluid, thereby speeding up the discharge of the fluid.

[0020] Furthermore, in the wastewater treatment system described in the present invention, the first filter plate is inclined at an angle of 15°~20°; a flower residue blowing device is provided on the inner wall of the flower residue filtering unit corresponding to the upper part of the highest point of the first filter plate, and the flower residue blowing device is connected to the air conveying unit pipeline.

[0021] In the present invention, the flower residue blowing device controls the air flow rate so that the flower residue on the first filter plate leaves as quickly as possible, thereby preventing the first filter plate from being blocked.

[0022] Further, in the wastewater treatment system of the present invention, the wastewater treatment system further includes a control system. Flow control valves are provided between adjacent devices among the air flotation separation unit, the flower residue filtration unit, the wastewater vacuum distillation and concentration unit, the ethanol purification unit, the first primary mixer, the centrifuge separator, the ethanol recovery unit, the concentrated hydrochloric acid acidolysis unit, the second primary mixer, the second secondary mixer, the filter separator, and the hydrochloric acid solution recovery unit. Flow control valves are provided between the ethanol storage and the ethanol purification unit and the ethanol recovery unit respectively. Flow control valves are provided between the concentrated hydrochloric acid storage and the hydrochloric acid solution recovery unit and the concentrated hydrochloric acid acidolysis unit respectively. Each flow control valve is electrically connected to the control system.

[0023] Further, in the wastewater treatment system of the present invention, the volume of the colored wastewater in the wastewater vacuum distillation and concentration unit becomes 18% - 25% of the original volume after vacuum distillation and concentration, and the pH value of the liquid in the concentrated hydrochloric acid acidolysis unit is 1.5 - 3.

[0024] Further, in the wastewater treatment system of the present invention, the concentration of the ethanol added to the ethanol purification unit is greater than or equal to 99.5%, and an ethanol spraying structure is provided at the top of the ethanol purification unit.

[0025] Further, in the wastewater treatment system of the present invention, the aperture of the filtration holes provided on the first filter plate is 3 mm - 6 mm.

[0026] Further, in the wastewater treatment system of the present invention, the horizontal distance between the third solid baffle and the second partition is greater than the horizontal distance between the first partition and the second partition.

[0027] On the other hand, the present invention provides a method for treating wastewater after the production of Damascus rose essential oil. The wastewater treatment method uses the above-mentioned wastewater treatment system, and the wastewater treatment method includes the following steps:

[0028] Step 1): The colored wastewater after the production of Damascus rose essential oil is added to the air flotation separation unit, the flower residues are flotation-collected, and then enter the flower residue filtration unit to remove the remaining flower residues therein to obtain the first colored wastewater;

[0029] Step 2): The first colored wastewater enters the wastewater vacuum distillation and concentration unit for concentration to 18% - 25% of the original volume to obtain concentrated colored wastewater. The concentrated colored wastewater enters the ethanol purification unit, ethanol is added and stirred. After reacting for 30 min - 40 min, it enters the first primary mixer, and then solid-liquid separation is carried out by a centrifuge separator to obtain the first purified colored liquid;

[0030] Step 3): The liquid after the ethanol in the first purified colored liquid is recovered by the ethanol recovery unit enters the concentrated hydrochloric acid acidolysis unit, and is continuously stirred, and concentrated hydrochloric acid is added to make the pH of the liquid in the concentrated hydrochloric acid acidolysis unit 1.5 - 3, and the reaction is carried out for 15 min - 25 min; the pigment mixture after the reaction under strong acid conditions is mixed successively through the second primary mixer and the second secondary mixer and continues to react to obtain the second pigment mixture; the ethanol recovered by the ethanol recovery unit is recycled to step 2) for use;

[0031] Step 4): The second pigment mixture is subjected to precipitation separation by a filter separator to obtain a solid plant pigment precipitate and a supernatant;

[0032] The solid plant pigment is collected and recycled, and the supernatant is recycled by the hydrochloric acid solution recovery unit to recover hydrochloric acid for step 3).

[0033] Compared with the prior art, the present invention has the following beneficial technical effects:

[0034] For the wastewater treatment system and method after the production of Damascus rose essential oil of the present invention, the plant pigment in Damascus rose is extracted from the wastewater after essential oil production, which is not only economically beneficial but also solves the problem of wastewater treatment. At the same time, the wastewater treatment system and method of the present invention can realize the complete extraction and recovery of plant pigments in colored wastewater, and the recycling of ethanol and hydrochloric acid used in the recovery process greatly reduces environmental pollution and production raw material costs. Description of the Drawings

[0035] Figure 1 It is a schematic framework diagram of the wastewater treatment system in the specific embodiment of the present invention;

[0036] Figure 2 It is a schematic structural diagram of the flower residue filtration unit in the specific embodiment of the present invention;

[0037] Figure 3 It is a schematic structural diagram of the filter separator in the specific embodiment of the present invention;

[0038] Figure 4 It is a schematic structural diagram of the first primary mixer and the second primary mixer in the specific embodiment of the present invention;

[0039] Figure 5 It is a schematic structural diagram of the second secondary mixer in the specific embodiment of the present invention;

[0040] Wherein: 1. Air flotation separation unit; 2. Flower residue filtration unit; 3. Ethanol purification unit; 4. Air transportation unit; 5. Ethanol storage; 6. Ethanol recovery unit; 7. Centrifugal separator; 8. First primary mixer; 9. Storage; 10. Concentrated hydrochloric acid hydrolysis unit; 11. Concentrated hydrochloric acid storage; 12. Second primary mixer; 13. Second secondary mixer; 14. Filter separator; 15. Hydrochloric acid solution concentration unit; 16. Hydrochloric acid solution recovery unit;

[0041] 101. Filter blowing plate; 200. Wastewater vacuum distillation and concentration unit;

[0042] 802. Shell; 801. Panel; 1301. Straight pipe part; 1302. Curved pipe part; 1302a. Convex lip unit;

[0043] 204. Filtration chamber; 205. Wastewater collection chamber; 206. Flower residue collection chamber; 202. First filter plate; 203. Second solid baffle; 201. First solid baffle;

[0044] 1402. First partition; 1403. Second filter plate; 1405. Second partition; 1404. Third solid baffle. Detailed implementation manners

[0045] For a clearer understanding of the technical features, objectives, and effects of the present invention, the detailed implementation manners of the present invention will now be described with reference to the accompanying drawings. The described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention. For those not specified in the detailed implementation manners, they are carried out according to conventional conditions or the conditions recommended by the manufacturer. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The exemplary embodiments described below do not represent all embodiments consistent with the present disclosure. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present disclosure as detailed in the appended claims. Detailed implementation manner one:

[0047] As Figures 1 to 5 shown, a wastewater treatment system for the production of Damascus rose essential oil according to the present invention includes: an air flotation separation unit 1, a flower residue filtration unit 2, a wastewater vacuum distillation and concentration unit 200, an ethanol purification unit 3, a first primary mixer 8, a centrifugal separator 7, an ethanol recovery unit 6, a concentrated hydrochloric acid hydrolysis unit 10, a second primary mixer 12, a second secondary mixer 13, a filter separator 14, a hydrochloric acid solution recovery unit 16, and a hydrochloric acid solution concentration unit 15, which are sequentially connected by pipelines along the flow direction of the colored wastewater;

[0048] The solid substances separated by the above-mentioned centrifugal separator 7 enter the memory 9. The ethanol vapor of the above-mentioned ethanol recovery unit 6 flows into the ethanol memory 5 and is supplied to the extraction process of the ethanol purification unit 3. A filter blowing plate 101 with a large number of air outlets is arranged at the bottom of the above-mentioned air flotation separation unit 1. The above-mentioned filter blowing plate 101 has a hollow inner cavity for air circulation, and the above-mentioned hollow inner cavity is communicated with the air delivery unit 4;

[0049] The recovered concentrated hydrochloric acid with a concentration ≥ 95% recovered and concentrated by the above-mentioned hydrochloric acid solution recovery unit 16 and the hydrochloric acid solution concentration unit 15 flows into the concentrated hydrochloric acid memory 11 and is supplied to the plant pigment extraction process of the above-mentioned concentrated hydrochloric acid acidolysis unit 10; The solid plant pigment substances separated by the above-mentioned filter separator 14 are collected and utilized through the bottom outlet;

[0050] The above-mentioned first primary mixer 8 and the second primary mixer 12 have the same structure, both of which are straight pipe mixers, and are composed of a pipe shell 802 and mixing components arranged in the above-mentioned pipe shell 802; The above-mentioned mixing components are composed of a plurality of panels 801 twisted at an angle of 25° - 55° continuously combined front and back; The length of the above-mentioned panel 801 is h2, the width is w2, and h2 = 1.5 - 2.2w2;

[0051] The above-mentioned mixing components continuously mix the fluid by repeatedly dividing, turning, and recombining the fluid flow passing through the pipeline, so that the plant pigments in the wastewater are fully precipitated.

[0052] The above-mentioned second secondary mixer 13 is a zigzag pipe structure, which is composed of an alternating connection of a straight pipe part 1301 and a curved pipe part 1302, and both the starting end and the ending end are straight pipe parts 1301; The inside of the above-mentioned curved pipe part 1302 has a plurality of convex lip units 1302a, and the above-mentioned convex lip units 1302a are evenly spaced along the length direction of the curved pipe part 1302. The three faces of the above-mentioned convex lip units 1302a facing the inner cavity of the above-mentioned curved pipe part 1302 are all trapezoidal faces, so that the inner surface of the above-mentioned curved pipe part 1302 forms a corrugated shape; The bending radian of the above-mentioned curved pipe part 1302 is 165° - 180°, the outer diameter length of the above-mentioned curved pipe part 1302 is 0.3 - 0.5 times the length of the above-mentioned straight pipe part 1301, and the pipe diameters of the above-mentioned curved pipe part 1302 and the above-mentioned straight pipe part 1301 are the same.

[0053] In some embodiments, the flower residue filtering unit 2 is divided into a filter chamber 204, a wastewater collection chamber 205 and a flower residue collection chamber 206 by a Y-shaped baffle. The filter chamber 204 corresponds to the wastewater outlet of the air flotation separation unit 1. The Y-shaped baffle includes a first filter plate 202, a second solid baffle 203 and a first solid baffle 201; only one edge of the first filter plate 202 is fixedly connected to the second solid baffle 203 and the first solid baffle 201, and the remaining edges of the first filter plate 202 are sealed and fixedly connected to the outer wall of the flower residue filtering unit 2; the upper end edge of the second solid baffle 203 is set as a blind end.

[0054] In some embodiments, the interior of the filter separator 14 is divided into a first sedimentation tank and a second sedimentation tank by a first partition 1402. A second filter plate 1403 is fixedly disposed on one side of the second sedimentation tank close to the liquid outlet. A second partition plate 1405 parallel to the first partition plate 1402 is vertically disposed at one end of the second filter plate 1403. A third solid baffle plate 1404 is disposed parallel to and above the second filter plate 1403, and the third solid baffle plate 1404 does not contact the second baffle plate 1405.

[0055] The first partition plate 1402 includes an upper partition plate and a lower partition plate, the lower partition plate is a solid plate for blocking sediments, the upper partition plate is a microfiltration membrane partition plate, and the second filter plate 1403 is a microfiltration membrane partition plate.

[0056] In some embodiments, the microfiltration membrane can be one of a mixed fiber microporous membrane, a polypropylene membrane, a polyethersulfone membrane, a polyvinylidene fluoride membrane, a polytetrafluoroethylene membrane, and a nylon membrane.

[0057] The upper partition and the second filter plate 1403 intercept the precipitated solid plant pigments and only allow the liquid to pass through, so that the solid plant pigments are precipitated to the bottom of the filter separator 14, and then the solid plant pigments are recycled. Through the ingenious design of the partition in the filter separator 14, the filter separator 14 can achieve precise filtration and complete recovery of the solid plant pigments.

[0058] The design of the third solid baffle 1404 can speed up the flow rate of the fluid, thereby speeding up the discharge of the fluid.

[0059] In some embodiments, the first filter plate 202 is tilted at an angle of 15° to 20°; a flower residue blowing device is provided on the inner wall of the flower residue filtering unit 2 corresponding to the upper part of the highest point of the first filter plate 202, and the flower residue blowing device is connected to the pipeline of the air conveying unit 4. The flower residue blowing device controls the air flow so that the flower residue on the first filter plate 202 leaves as soon as possible to prevent the first filter plate 202 from being blocked.

[0060] In some embodiments, the above wastewater treatment system further includes a control system. Flow control valves are provided between adjacent devices in the air flotation separation unit 1, the flower residue filtration unit 2, the wastewater vacuum distillation and concentration unit 200, the ethanol purification unit 3, the first primary mixer 8, the centrifuge 7, the ethanol recovery unit 6, the concentrated hydrochloric acid hydrolysis unit 10, the second primary mixer 12, the second secondary mixer 13, the filter separator 14, and the hydrochloric acid solution recovery unit 16. Flow control valves are provided between the ethanol storage 5 and the ethanol purification unit 3 and the ethanol recovery unit 6 respectively. Flow control valves are provided between the concentrated hydrochloric acid storage 11 and the hydrochloric acid solution recovery unit 16 and the concentrated hydrochloric acid hydrolysis unit 10 respectively. Each of the above flow control valves is electrically connected to the control system.

[0061] The volume of the colored wastewater in the wastewater vacuum distillation and concentration unit 200 becomes 18% - 25% of the original volume after vacuum distillation and concentration, and the pH value of the liquid in the concentrated hydrochloric acid hydrolysis unit 10 is 1.5 - 3.

[0062] In some embodiments, the concentration of the ethanol added to the ethanol purification unit 3 is greater than or equal to 99.5%, and an ethanol spraying structure is provided at the top of the ethanol purification unit 3.

[0063] In some embodiments, the aperture of the filtration holes provided on the first filter plate 202 is 3 mm - 6 mm.

[0064] In some embodiments, the horizontal distance between the third solid baffle 1404 and the second partition 1405 is greater than the horizontal distance between the first partition 1402 and the second partition 1405. Specific Embodiment 2:

[0066] A method for treating wastewater after the production of Damascus rose essential oil according to the present invention uses the wastewater treatment system described in Specific Embodiment 1. The above wastewater treatment method includes the following steps:

[0067] Step 1): The colored wastewater after the production of Damascus rose essential oil is added to the air flotation separation unit 1, the flower residues are flotation-collected, and then enter the flower residue filtration unit 2 to remove the remaining flower residues to obtain the first colored wastewater;

[0068] Step 2): The above first colored wastewater enters the wastewater vacuum distillation and concentration unit 200 for concentration to 18% - 25% of the original volume to obtain concentrated colored wastewater. The concentrated colored wastewater enters the ethanol purification unit 3, ethanol is added and stirred. After reacting for 30 min - 40 min, it enters the first primary mixer 8, and then solid-liquid separation is performed by the centrifuge 7 to obtain the first purified colored liquid;

[0069] Step 3): The liquid after the ethanol in the above-mentioned first purified colored liquid is recovered by the ethanol recovery unit 6 enters the concentrated hydrochloric acid acidolysis unit 10, and is continuously stirred, and concentrated hydrochloric acid is added to make the pH of the liquid in the above-mentioned concentrated hydrochloric acid acidolysis unit 10 1.5-3, and the reaction is carried out for 15 min-25 min; the pigment mixture after the reaction under strong acid conditions is then mixed and reacted through the second primary mixer 12 and the second secondary mixer 13 in sequence to obtain a second pigment mixture; the ethanol recovered by the above-mentioned ethanol recovery unit 6 is recycled to the above-mentioned step 2) for use;

[0070] Step 4): The above-mentioned second pigment mixture is subjected to precipitation separation by a filter separator 14 to obtain a solid plant pigment precipitate and a supernatant;

[0071] The above-mentioned solid plant pigment is collected and recycled, and the above-mentioned supernatant is recovered by the hydrochloric acid solution recovery unit 16 for hydrochloric acid used in the above-mentioned step 3).

[0072] The present invention is illustrated by the above specific embodiments and examples. Those skilled in the art should understand that various transformations and equivalent substitutions can be made to the present invention without departing from the scope of the present invention. The parts not detailed in the description of the present invention are well-known technologies to those skilled in the art. In addition, various modifications can be made to the present invention for specific situations or circumstances without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed, but should include all embodiments falling within the scope of the claims of the present invention.

Claims

1. A wastewater treatment system after the production of Damascus rose essential oil, characterized in that, Including: An air flotation separation unit (1), a flower residue filtration unit (2), a wastewater vacuum distillation and concentration unit (200), an ethanol purification unit (3), a first primary mixer (8), a centrifugal separator (7), an ethanol recovery unit (6), a concentrated hydrochloric acid acidolysis unit (10), a second primary mixer (12), a second secondary mixer (13), a filtration separator (14), a hydrochloric acid solution recovery unit (16), and a hydrochloric acid solution concentration unit (15) that are connected in sequence by pipelines along the flowing direction of the colored wastewater; The solid substances separated by the centrifugal separator (7) enter the storage (9). The ethanol vapor of the ethanol recovery unit (6) flows into the ethanol storage (5) and is supplied to the extraction process of the ethanol purification unit (3). The bottom of the air flotation separation unit (1) is provided with a filtration and blowing plate (101) having an air outlet. The filtration and blowing plate (101) has a hollow inner cavity for air circulation, and the hollow inner cavity is communicated with the air delivery unit (4); The hydrochloric acid solution recovery unit (16) and the hydrochloric acid solution concentration unit (15) recover and concentrate to obtain a recovered concentrated hydrochloric acid with a mass concentration ≥ 95%. The recovered concentrated hydrochloric acid flows into the concentrated hydrochloric acid storage (11) and is used for the plant pigment extraction process of the concentrated hydrochloric acid acidolysis unit (10); The solid plant pigment substances separated by the filtration separator (14) are collected and utilized through the bottom outlet; The first primary mixer (8) and the second primary mixer (12) have the same structure and are both straight pipe mixers, which are composed of a pipe shell (802) and mixing components arranged in the pipe shell (802); The mixing components are composed of a plurality of panels (801) twisted at an angle of 25° to 55° continuously combined front and back; The length of the panel (801) is h2, the width is w2, and h2 = 1.5 to 2.2w2; The mixing components continuously mix the fluid by repeatedly dividing, turning, and recombining the fluid flow passing through the pipeline, so that the plant pigments in the wastewater are fully precipitated; The second secondary mixer (13) is a zigzag pipe structure, which is composed of an alternating connection of a straight pipe part (1301) and a curved pipe part (1302). Both the start end and the end are straight pipe parts (1301); The inside of the curved pipe part (1302) has a plurality of convex lip units (1302a). The convex lip units (1302a) are evenly spaced along the length direction of the curved pipe part (1302). The three surfaces of the convex lip units (1302a) facing the inner cavity of the curved pipe part (1302) are trapezoidal surfaces, so that the inner surface of the curved pipe part (1302) forms a corrugated shape; The bending radian of the curved pipe part (1302) is 165° to 180°. The outer diameter length of the curved pipe part (1302) is 0.3 to 0.5 times the length of the straight pipe part (1301), and the pipe diameters of the curved pipe part (1302) and the straight pipe part (1301) are the same.

2. The wastewater treatment system according to claim 1, characterized in that, The flower residue filtering unit (2) is divided into a filtering chamber (204), a wastewater collection chamber (205) and a flower residue collection chamber (206) by a Y-shaped baffle. The filtering chamber (204) corresponds to the wastewater outlet of the air flotation separation unit (1). The Y-shaped baffle includes a first filter plate (202), a second solid baffle (203) and a first solid baffle (201). Only one side of the first filter plate (202) is fixedly connected to the second solid baffle (203) and the first solid baffle (201), and the remaining sides of the first filter plate (202) are hermetically and fixedly connected to the outer wall of the flower residue filtering unit (2). The upper end edge of the second solid baffle (203) is set as a blind end.

3. The wastewater treatment system according to claim 2, wherein The interior of the filtering separator (14) is divided into a first sedimentation tank and a second sedimentation tank by a first partition plate (1402). A second filter plate (1403) is fixedly arranged on one side of the second sedimentation tank close to the liquid outlet. One end of the second filter plate (1403) is vertically provided with a second partition plate (1405) parallel to the first partition plate (1402). A third solid baffle (1404) is arranged above the second filter plate (1403) in parallel, and the third solid baffle (1404) does not contact the second partition plate (1405). The first partition plate (1402) includes an upper partition plate and a lower partition plate. The lower partition plate is a solid plate for blocking sediment, and the upper partition plate is a microfiltration membrane partition plate. The second filter plate (1403) is a microfiltration membrane partition plate.

4. The wastewater treatment system according to claim 3, wherein, The first filter plate (202) is inclined, and the inclination angle is 15°-20°. A flower residue blowing device is arranged on the inner wall of the flower residue filtering unit (2) corresponding to the upper part of the highest point of the first filter plate (202). The flower residue blowing device is communicated with the air conveying unit (4) through a pipeline.

5. The wastewater treatment system according to claim 4, characterized in that, The wastewater treatment system further includes a control system. Flow control valves are arranged between adjacent devices in the air flotation separation unit (1), the flower residue filtering unit (2), the wastewater vacuum distillation and concentration unit (200), the ethanol purification unit (3), the first primary mixer (8), the centrifuge separator (7), the ethanol recovery unit (6), the concentrated hydrochloric acid acidolysis unit (10), the second primary mixer (12), the second secondary mixer (13), the filtering separator (14) and the hydrochloric acid solution recovery unit (16). Flow control valves are respectively arranged between the ethanol storage tank (5) and the ethanol purification unit (3) and the ethanol recovery unit (6). Flow control valves are respectively arranged between the concentrated hydrochloric acid storage tank (11) and the hydrochloric acid solution recovery unit (16) and the concentrated hydrochloric acid acidolysis unit (10). Each flow control valve is electrically connected to the control system.

6. The wastewater treatment system according to claim 5, characterized in that, The volume of the colored wastewater in the wastewater vacuum distillation and concentration unit (200) after vacuum distillation and concentration is 18%-25% of the original volume. The pH value of the liquid in the concentrated hydrochloric acid acidolysis unit (10) is 1.5-3.

7. The wastewater treatment system according to claim 6, wherein The concentration of ethanol added to the ethanol purification unit (3) is greater than or equal to 99.5%, and an ethanol spraying structure is provided at the top of the ethanol purification unit (3).

8. The wastewater treatment system according to claim 7, wherein The aperture of the filtration holes provided on the first filter plate (202) is 3 mm to 6 mm.

9. The wastewater treatment system according to claim 8, characterized in that, The horizontal distance between the third solid baffle (1404) and the second partition plate (1405) is greater than the horizontal distance between the first partition plate (1402) and the second partition plate (1405).

10. A wastewater treatment method after the production of Damascus rose essential oil, characterized in that, The wastewater treatment method uses the wastewater treatment system according to any one of claims 1 to 9, and the wastewater treatment method includes the following steps: Step 1): The colored wastewater after the production of Damascus rose essential oil is added to the air flotation separation unit (1), the flower dregs are flotation-collected, and then enter the flower dregs filtration unit (2) to remove the remaining flower dregs therein to obtain the first colored wastewater. Step 2): The first colored wastewater enters the wastewater vacuum distillation and concentration unit (200) for concentration to 18% to 25% of the original volume to obtain concentrated colored wastewater. The concentrated colored wastewater enters the ethanol purification unit (3), ethanol is added and stirred, after reacting for 30 min to 40 min, it enters the first primary mixer (8), and then passes through the centrifugal separator (7) for solid-liquid separation to obtain the first purified colored liquid. Step 3): The liquid after the ethanol in the first purified colored liquid is recovered by the ethanol recovery unit (6) enters the concentrated hydrochloric acid acidolysis unit (10), and is continuously stirred, and concentrated hydrochloric acid is added to make the pH of the liquid in the concentrated hydrochloric acid acidolysis unit (10) 1.5 to 3, and react for 15 min to 25 min; then it passes through the second primary mixer (12) and the second secondary mixer (13) in sequence for mixing and continues to react to obtain the second pigment mixture; the ethanol recovered by the ethanol recovery unit (6) is recycled to step 2) for use. Step 4): The second pigment mixture is subjected to precipitation separation by the filter separator (14) to obtain a solid plant pigment precipitate and a supernatant. The solid plant pigment is collected and recycled, and the supernatant is recovered by the hydrochloric acid solution recovery unit (16) to recover hydrochloric acid for use in step 3).

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