Active sludge fluorescence online detection device based on flow cell

Abstract

The invention discloses an activated sludge fluorescence online detection device based on a flow cell, and relates to the field of activated sludge biomass detection.The activated sludge fluorescence online detection device comprises a fluorescence spectrophotometer and a fluorescence spectrophotometer sample table arranged on the fluorescence spectrophotometer, and the fluorescence spectrophotometer is connected with a processor through a cable; the fluorescence spectrophotometer sample table is connected with a sample cup through a guide pipe, activated sludge is arranged in the sample cup, and a peristaltic pump is arranged on the guide pipe; the activated sludge continuously flows through the fluorescence spectrophotometer sample table through the guide pipe for three-dimensional fluorescence detection through the peristaltic pump, sludge sedimentation in a traditional cuvette is avoided, measurement is simple and convenient, and on-line real-time monitoring of the activated sludge biomass can be achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of activated sludge biomass detection, in particular to an activated sludge fluorescence online detection device based on a flow cell. BACKGROUND

[0002] After a certain wavelength of light excites the fluorescent substance, it emits light with a wavelength longer than the excitation wavelength in a very short time. This light is called fluorescence. During the entire fluorescence emission process of the fluorescent substance, a specific fluorescent substance has specific excitation and emission wavelengths. The fluorescence intensity of the fluorescent substance is related to its concentration. Therefore, the concentration of the fluorescent substance can be inferred according to its intensity.

[0003] In the prior art, the process of detecting volatile suspended solids (vss) is complicated and time-consuming. Traditional infrared or visible absorbance can only detect total solid concentration, but cannot detect biomass, which cannot meet the current development needs of intelligent wastewater treatment plants for fast and accurate online data collection.

[0004] Three-dimensional fluorescence spectroscopy is a fast and accurate detection method without the need for chemical addition and pretreatment, and is expected to realize rapid detection and characterization of sludge biochemical properties. However, when using traditional fluorescence detection methods, activated sludge will settle in a cuvette, and due to scattering and internal filtration, the upper limit of the concentration detected is low, so dilution is required when measuring activated sludge, which can easily cause pollution and errors.

[0005] Therefore, the present application provides an activated sludge fluorescence online detection device based on a flow cell to solve the above problems. SUMMARY

[0006] The purpose of the present application is to provide an activated sludge fluorescence online detection device based on a flow cell, which realizes continuous flow fluorescence detection of activated sludge, avoids the problem of settling, and realizes online, fast and accurate biomass monitoring.

[0007] To achieve the above purpose, the present application provides an activated sludge fluorescence online detection device based on a flow cell, which comprises a fluorescence spectrophotometer and a fluorescence spectrophotometer sample stage arranged on the fluorescence spectrophotometer. The fluorescence spectrophotometer is connected to a processor through a cable. The fluorescence spectrophotometer sample stage is connected to a sample cup through a conduit. The inside of the sample cup is provided with activated sludge. A peristaltic pump is arranged on the conduit.

[0008] Preferably, the fluorescence spectrophotometer sample stage is made of black light-proof and non-reflective material. The fluorescence spectrophotometer sample stage comprises a bottom plate and a fixing groove arranged on the bottom plate. The fixing groove is arranged corresponding to the light source of the fluorescence spectrophotometer. The bottom plate is provided with a positioning hole, a first screw hole and a second screw hole. The bottom plate is fixed on the fluorescence spectrophotometer through the positioning hole, the first screw hole and the second screw hole.

[0009] Preferably, a flow-through tube is arranged on the bottom plate, the flow-through tube passes through the fixing groove and the bottom plate in sequence, the four side walls of the fixing groove are each provided with an observation hole, the observation holes are arranged correspondingly with the flow-through tube, the inside of the fixing groove is provided with a light shield, the light shield is arranged closely with the flow-through tube, and the included angle between the light shield and the light source of the fluorescence spectrophotometer is 45°.

[0010] Preferably, the fixing groove is arranged at the upper left corner of the bottom plate, the distance between the fixing groove and the edge of the bottom plate is 18mm*18mm, the size of the bottom plate is 90mm*110mm, the size of the fixing groove is 24mm*24mm*55mm, the inner diameter of the fixing groove is 5mm, the size of the observation hole is 3mm*20mm, the thickness of the light shield is 2mm, and the height of the light shield is 53mm.

[0011] Preferably, the two ends of the flow-through tube are provided with a guide pipe, the guide pipe is connected to the flow-through tube in a socket manner, the other end of the guide pipe is arranged in the inside of the sample cup, the guide pipe is a plastic hose, the flow-through tube is a quartz glass tube, and the thickness of the quartz glass tube is 1mm.

[0012] Preferably, the excitation wavelength of the fluorescence spectrophotometer is 250-550nm, the emission wavelength is 250-550nm, the excitation slit width and the emission slit width are both 5nm, the sensitivity is 1ow, the excitation wavelength scanning interval is 5nm, the emission wavelength scanning interval is 1nm, and the scanning speed is 30000nm / s.

[0013] Preferably, the distance between the positioning hole and the edge of the bottom plate is 4mm*9mm, the size of the positioning hole is 6mm*10mm, the distance between the first screw hole and the edge of the bottom plate is 4mm*3mm, the diameter of the first screw hole is 8mm, the distance between the second screw hole and the edge of the bottom plate is 5mm*9mm, and the diameter of the second screw hole is 6mm.

[0014] Therefore, the active sludge fluorescence online detection device based on the flow cell has the following beneficial effects: (1) The flow cell design is adopted in the scheme to cooperate with the peristaltic pump, so that the active sludge continuously flows through the quartz flow-through tube, and the sludge settlement problem in the traditional cuvette is avoided; (2) The short-path quartz flow-through tube is used in the scheme to replace the cuvette, which effectively reduces the fluorescence inner filter effect and light scattering interference, and improves the detection upper limit of high-concentration sludge samples; (3) The scheme combines three-dimensional fluorescence spectrum technology, realizes real-time fluorescence detection without pretreatment and chemical reagents, and meets the needs of intelligent data rapid and continuous acquisition of sewage treatment plants.

[0015] The method scheme of the present application is further described in detail below by means of the accompanying drawings and examples. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 Figure 1 is a structural diagram of an online activated sludge fluorescence detection device based on a flow cell according to the present application. Figure 2 Figure 2 is a structural diagram of a sample stage of a fluorescence spectrophotometer according to the present application. Figure 3 Figure 3 is a three-view diagram of a sample stage of a fluorescence spectrophotometer according to the present application. Figure 4 Figure 4 is a sectional view of a fixed groove according to the present application. Figure 5 Figure 5 is a schematic diagram showing the change of fluorescence response value at EX / EM = 280 / 340 nm with sludge vss concentration measured by an embodiment of the present application. Figure 6 Figure 6 is a schematic diagram of fluorescence results of online activated sludge fluorescence detection by an embodiment of the present application.

[0017] In the figure, 1 is a fluorescence spectrophotometer, 2 is a sample stage of a fluorescence spectrophotometer, 3 is a cable, 4 is a processor, 5 is a conduit, 6 is a sample cup, 7 is activated sludge, 8 is a peristaltic pump, 9 is a bottom plate, 10 is a fixed groove, 11 is a positioning hole, 12 is a first screw hole, 13 is a second screw hole, 14 is a flow tube, 15 is an observation hole, and 16 is a light barrier. DETAILED DESCRIPTION

[0018] The method scheme of the present application is further described in detail below by means of the accompanying drawings and examples.

[0019] Unless otherwise defined, the method terms or scientific terms used in the present application shall have the usual meanings understood by persons with ordinary skills in the art to which the present application belongs.

[0020] The "including" or "comprising" and similar words used in the present invention mean that the elements before the word encompass the elements listed after the word, and do not exclude the possibility of also encompassing other elements. The orientation or positional relationship indicated by the terms "in", "out", "upper", "lower" and the like is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present invention, and when the absolute position of the described object changes, the relative positional relationship may also change accordingly. In the present invention, unless otherwise explicitly specified and limited, the term "attached" and the like should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above-mentioned terms in the present invention can be understood according to the specific circumstances.

[0021] Embodiment As Figures 1-6 shown, the present application provides a flow cell-based activated sludge fluorescence online detection device, which comprises a fluorescence spectrophotometer 1 and a fluorescence spectrophotometer sample table 2 arranged on the fluorescence spectrophotometer 1. The fluorescence spectrophotometer 1 is connected with a processor 4 through a cable 3. The fluorescence spectrophotometer sample table 2 is connected with a sample cup 6 through a conduit 5. The inside of the sample cup 6 is provided with activated sludge 7. A peristaltic pump 8 is arranged on the conduit 5, and the activated sludge 7 to be measured is transported through the peristaltic pump 8.

[0022] The fluorescence spectrophotometer 1 adopts Shimadzu RF6000. The excitation wavelength of the fluorescence spectrophotometer 1 is set to 250-550 nm, the emission wavelength is set to 250-550 nm, the excitation slit width and the emission slit width are both set to 5 nm, the sensitivity is set to 1ow, the excitation wavelength scanning interval is set to 5 nm, the emission wavelength scanning interval is set to 1 nm, and the scanning speed is set to 30000 nm / s.

[0023] The fluorescence spectrophotometer sample table 2 adopts a black light-proof and non-reflective material. In this embodiment, the fluorescence spectrophotometer sample table 2 is obtained by 3D printing. The fluorescence spectrophotometer sample table 2 comprises a bottom plate 9 and a fixing groove 10 arranged on the bottom plate 9. The fixing groove 10 is arranged corresponding to the light source of the fluorescence spectrophotometer 1. The bottom plate 9 is provided with a positioning hole 11, a first screw hole 12 and a second screw hole 13. The bottom plate 9 is fixed on the fluorescence spectrophotometer 1 through the positioning hole 11, the first screw hole 12 and the second screw hole 13.

[0024] The distance between the positioning hole 11 and the edge of the bottom plate 9 is set to 4mmx9mm, the size of the positioning hole 11 is set to 6mmx10mm, the distance between the first screw hole 12 and the edge of the bottom plate 9 is set to 4mmx3mm, the diameter of the first screw hole 12 is set to 8mm, the distance between the second screw hole 13 and the edge of the bottom plate 9 is set to 5mmx9mm, and the diameter of the second screw hole 13 is set to 6mm.

[0025] The bottom plate 9 is provided with a flow tube 14, which is used to replace the traditional cuvette to hold the activated sludge 7 to be detected during the detection process. The flow tube 14 passes through the fixed groove 10 and the bottom plate 9 in turn. The fixed groove 10 is provided with an observation hole 15 on each of the four groove walls. The observation hole 15 is arranged correspondingly with the flow tube 14. The fixed groove 10 is provided with a light barrier 16 inside, which is arranged closely with the flow tube 14 to avoid the reflection of the excitation light into the detector of the fluorescence spectrophotometer 1 through the flow tube. The included angle between the light barrier 16 and the light source of the fluorescence spectrophotometer 1 is set to 45°. The light source of the fluorescence spectrophotometer 1 emits excitation light, which is vertically irradiated on the flow tube 14 through the observation hole 15.

[0026] The fixed groove 10 is arranged at the upper left corner of the bottom plate 9. The distance between the fixed groove 10 and the edge of the bottom plate 9 is set to 18mmx18mm. The size of the bottom plate 9 is set to 90mmx110mm. The size of the fixed groove 10 is set to 24mmx24mmx55mm. The inner diameter of the fixed groove 10 is set to 5mm. The size of the observation hole 15 is set to 3mmx20mm. The thickness of the light barrier 16 is set to 2mm. The height of the light barrier 16 is set to 53mm.

[0027] Both ends of the flow tube 14 are provided with a conduit 5, which is inserted between the flow tube 14. The other end of the conduit 5 is arranged inside the sample cup 6. The conduit 5 is arranged as a plastic hose. The flow tube 14 is arranged as a quartz glass tube. The thickness of the quartz glass tube is set to 1mm.

[0028] In actual application process, in order to eliminate errors, the activated sludge 7 needs to be aerated and stirred during the entire fluorescence scanning process, so that the activated sludge 7 is uniformly mixed. In order to avoid the influence of reflection on fluorescence detection, the width of the observation hole 15 in the fluorescence spectrophotometer sample table 2 needs to be consistent with and aligned with the inner diameter of the flow tube 14, and at the same time, the flow tube 14 needs to be in close contact with the fixed groove 10.

[0029] Finally, the fluorescence detection is carried out. The detector of the fluorescence spectrophotometer 1 directly reads the fluorescence response value at the wavelength of 280 / 340nm of the excitation light or the emitted light. The read data is transmitted to the processor 4. The average value of multiple measurements is taken to measure the vss concentration of the sample.

[0030] Therefore, the application adopts the above-mentioned online activated sludge fluorescence detection device based on a flow cell, compared with the traditional measurement of vss to obtain the activated sludge biomass, the operation is simple, the measurement time is short, meanwhile, the quartz flow tube is shorter than the colorimetric cell in the optical path, there is no sludge sedimentation problem, the biomass of the activated sludge can be accurately characterized online, and the online fluorescence analysis of the activated sludge biomass is realized.

[0031] Finally, it should be noted that the above examples are only used to illustrate the method scheme of the present application, but not to limit it. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the method scheme of the present application can still be modified or replaced by equivalents, and these modifications or equivalent replacements should not make the modified method scheme deviate from the spirit and scope of the method scheme of the present application.

Claims

1. An online fluorescence detection device for activated sludge based on a flow-through tank, characterized in that, It includes a fluorescence spectrophotometer and a fluorescence spectrophotometer sample stage mounted on the fluorescence spectrophotometer. The fluorescence spectrophotometer is connected to the processor via a cable, and the fluorescence spectrophotometer sample stage is connected to the sample cup via a conduit. The sample cup contains activated sludge, and a peristaltic pump is mounted on the conduit.

2. The online fluorescence detection device for activated sludge based on a flow-through tank according to claim 1, characterized in that, The sample stage of the fluorescence spectrophotometer is made of black, opaque, and non-reflective material. The sample stage includes a base plate and a fixing groove set on the base plate. The fixing groove is set to correspond to the light source of the fluorescence spectrophotometer. The base plate is provided with positioning holes, a first screw hole, and a second screw hole. The base plate is fixed to the fluorescence spectrophotometer through the positioning holes, the first screw hole, and the second screw hole.

3. The online fluorescence detection device for activated sludge based on a flow-through tank according to claim 2, characterized in that, A flow tube is installed on the base plate, which passes through the fixed groove and the base plate in sequence. Observation holes are provided on all four walls of the fixed groove, and the observation holes are set in correspondence with the flow tube. A light-blocking plate is installed inside the fixed groove, which is set in close contact with the flow tube. The angle between the light-blocking plate and the light source of the fluorescence spectrophotometer is set to 45°.

4. The online fluorescence detection device for activated sludge based on a flow-through tank according to claim 3, characterized in that, The fixing groove is located at the upper left corner of the base plate. The distance between the fixing groove and the edge of the base plate is set to 18mm×18mm. The size of the base plate is set to 90mm×110mm. The size of the fixing groove is set to 24mm×24mm×55mm. The inner diameter of the fixing groove is set to 5mm. The size of the observation hole is set to 3mm×20mm. The thickness of the light-blocking plate is set to 2mm. The height of the light-blocking plate is set to 53mm.

5. The online fluorescence detection device for activated sludge based on a flow-through tank according to claim 3, characterized in that, The flow tube has conduits at both ends, with a socket between them. The other end of the conduit is placed inside the sample cup. The conduit is a plastic flexible tube, and the flow tube is a quartz glass tube with a thickness of 1 mm.

6. The online fluorescence detection device for activated sludge based on a flow-through tank according to claim 1, characterized in that, The excitation wavelength of the fluorescence spectrophotometer was set to 250-550 nm, the emission wavelength was set to 250-550 nm, the excitation slit width and the emission slit width were both set to 5 nm, the sensitivity was set to 1 ow, the excitation wavelength scanning interval was set to 5 nm, the emission wavelength scanning interval was set to 1 nm, and the scanning speed was set to 30000 nm / s.

7. The online fluorescence detection device for activated sludge based on a flow-through tank according to claim 2, characterized in that, The distance between the positioning hole and the edge of the base plate is set to 4mm×9mm, and the size of the positioning hole is set to 6mm×10mm. The distance between the first screw hole and the edge of the base plate is set to 4mm×3mm, and the diameter of the first screw hole is set to 8mm. The distance between the second screw hole and the edge of the base plate is set to 5mm×9mm, and the diameter of the second screw hole is set to 6mm.

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