A device for detecting the phosphorus capacity of sludge

Abstract

A detection device for sludge phosphorus capacity, comprising a sludge storage device, a phosphate solution storage device, a mixing reaction device, a monitoring device and a controller; both the sludge storage device and the phosphate solution storage device are communicated with the mixing reaction device. The sludge storage device transports the sludge to be detected stored therein to the mixing reaction device through a first delivery pump, and the phosphate solution storage device transports the phosphate solution stored therein to the mixing reaction device through a second delivery pump. The phosphate solution and the sludge to be detected are mixed and reacted to form a mixture; the monitoring device is used to monitor the phosphorus concentration and sludge concentration of the mixture in the mixing reaction device; the controller obtains the phosphorus capacity of the sludge to be detected according to the phosphorus concentration and sludge concentration. The detection device involved in the present invention calculates and obtains the sludge phosphorus capacity by detecting the sludge concentration and phosphorus concentration, so as to obtain the phosphorus removal ability of the sludge itself, and provide an intuitive data representation for making full use of the phosphorus removal ability of chemical agents in the sludge.

Description

Technical Field

[0001] The present invention belongs to the technical field of sewage treatment, and more specifically, relates to a device for detecting the phosphorus capacity of sludge. Background Art

[0002] To further improve the water environment quality, the pollutant discharge standards of sewage treatment plants have been further improved. Among them, the discharge standard of total phosphorus has become increasingly strict. For urban sewage treatment plants, chemical and biological phosphorus removal is most widely used. However, due to the influence of factors such as influent carbon source, anaerobic environment, and nitrate nitrogen on biological phosphorus removal, it is difficult to control the biological phosphorus removal effect of the water plant itself.

[0003] At present, most water plants mainly rely on chemical phosphorus removal, that is, adding phosphorus removal agents to sewage sludge. To ensure that the phosphorus in the effluent reaches the standard stably, that is, the effluent meets the discharge standard in real time, the phosphorus removal agents are generally added in excess. This leads to some unreacted phosphorus removal agents and hydrolysis products flowing back into the front-end biological treatment system with the sludge. The residue of these phosphorus removal agents makes the sludge have a strong phosphorus removal ability. The phosphorus removal ability of sludge can be represented by the phosphorus capacity of sludge. The phosphorus capacity of sludge is a definition when the phosphorus removal ability of sludge reaches saturation. In addition, sludge has a large specific surface area and a developed pore structure, and even without phosphorus removal agents, it has a certain ability to remove phosphorus in sewage. Although the sludge in water plants has a strong physicochemical phosphorus removal ability, current research mainly focuses on realizing the automatic control of reagent dosing through means such as feedforward and feedback, and there is a lack of a characterization index and detection method for the physicochemical phosphorus removal ability and duration of the sludge itself. As a result, the calculation accuracy of the automatic dosing system is low, and the phosphorus removal ability of the reagents in the sludge is not fully utilized, resulting in a waste of resources. Therefore, a device for detecting the phosphorus capacity of sludge is needed to solve the above problems. Summary of the Invention

[0004] The purpose of the present invention is to provide a device for detecting the phosphorus capacity of sludge to solve the problem that the physicochemical phosphorus removal ability of sludge in sewage treatment plants cannot be accurately characterized.

[0005] To achieve the above purpose, the present invention provides a device for detecting the phosphorus capacity of sludge, including a sludge storage device, a phosphate solution storage device, a mixing and reaction device, a monitoring device, and a controller;

[0006] The sludge storage device and the phosphate solution storage device are both connected to the mixing and reaction device. The sludge storage device transports the sludge to be detected stored therein into the mixing and reaction device through a first delivery pump, and the phosphate solution storage device transports the phosphate solution stored therein into the mixing and reaction device through a second delivery pump. The phosphate solution and the sludge to be detected are mixed and reacted to form a mixture;

[0007] The monitoring device is used to monitor the phosphorus concentration and sludge concentration of the mixture in the mixing reaction device;

[0008] The controller obtains the phosphorus capacity of the sludge to be detected according to the phosphorus concentration and the sludge concentration.

[0009] Preferably, the mixing reaction device includes a reaction bottle and a magnetic stirrer. The reaction bottle is placed on the magnetic stirrer. The reaction bottle is respectively communicated with the sludge storage device through a sludge sampling pipe and with the phosphate solution storage device through a phosphate solution sampling pipe. The first delivery pump is arranged on the sludge sampling pipe, and the second delivery pump is arranged on the phosphate solution sampling pipe;

[0010] The magnetic stirrer is used to stir the mixture in the reaction bottle.

[0011] Preferably, one end of the sludge sampling pipe is arranged on the side wall of the reaction bottle, and the other end of the sludge sampling pipe is arranged in the middle of the sludge storage device;

[0012] One end of the phosphate solution sampling pipe is arranged on the top of the reaction bottle, and the other end of the phosphate solution sampling pipe is arranged in the middle of the phosphate solution storage device;

[0013] A first valve is arranged on the sludge sampling pipe, and a second valve is arranged on the phosphate solution sampling pipe.

[0014] Preferably, the monitoring device includes a housing, a phosphate sampling pipe, a sludge concentration monitoring probe, and a display screen, a phosphate detection reagent bottle, a photometer, and a processing module arranged inside the housing;

[0015] One end of the phosphate sampling pipe is arranged in the reaction bottle, and the other end is communicated with the phosphate detection reagent bottle, and the mixture in the reaction bottle is transported to the phosphate detection reagent bottle for reaction by a pump. The photometer is used to measure the phosphorus concentration in the phosphate detection reagent bottle;

[0016] The sludge concentration monitoring probe is arranged in the reaction bottle and is used to detect the sludge concentration in the reaction bottle;

[0017] The processing module is electrically connected to the photometer and the sludge concentration monitoring probe respectively to obtain the phosphorus concentration and the sludge concentration;

[0018] The display screen displays the phosphorus concentration and the sludge concentration.

[0019] Preferably, the monitoring device further includes a dissolved oxygen monitoring probe and a redox potential monitoring probe. The dissolved oxygen monitoring probe and the redox potential monitoring probe are both inserted into the reaction flask and electrically connected to the processing module. The processing module respectively obtains the dissolved oxygen concentration and the redox potential detected by the dissolved oxygen monitoring probe and the redox potential monitoring probe.

[0020] Preferably, the detection device further includes a storage module; the controller is communicatively connected to the processing module and electrically connected to the magnetic stirrer and the second delivery pump;

[0021] The storage module is used to store the phosphorus concentration, the sludge concentration, the dissolved oxygen concentration, and the redox potential.

[0022] Preferably, the controller receives the phosphorus concentration, the sludge concentration, the dissolved oxygen concentration, and the redox potential transmitted by the processing module;

[0023] When the dissolved oxygen concentration is higher than the first concentration threshold and the redox potential is greater than the first potential threshold, the controller controls the stirring speed of the magnetic stirrer to decrease;

[0024] When the dissolved oxygen concentration is lower than the second concentration threshold and the redox potential is less than the second potential threshold, the controller controls the stirring speed of the magnetic stirrer to increase;

[0025] When the growth rate of the phosphorus concentration is greater than the third concentration threshold, the mixing reaction of the mixture in the reaction flask ends, and the controller controls the second delivery pump to close.

[0026] Preferably, a metering device is provided on the phosphate solution sampling tube, and / or,

[0027] The second delivery pump is a metering pump for obtaining the sampling volume of the phosphate solution for the mixing reaction;

[0028] The controller calculates the phosphorus capacity absorbed by the sludge per unit volume according to the following formula:

[0029] Phosphorus capacity = (phosphate solution sampling volume / 1000 + sludge volume) * phosphorus concentration reduction amount / (phosphate solution sampling volume / 1000 + sludge volume) * (sludge concentration / 1000), where,

[0030] The phosphorus concentration reduction amount represents the difference between the phosphorus concentration before the mixing reaction and the phosphorus concentration after the mixing reaction;

[0031] The sludge volume represents the volume of the sludge to be detected delivered to the reaction flask through the first delivery pump.

[0032] Preferably, the phosphate sampling tube communicates with the phosphate detection reagent bottle through a sampling pipeline, and a filtering device is provided on the sampling pipeline.

[0033] Preferably, a stirrer is provided in the sludge storage device, and a drain opening is provided at the bottom.

[0034] A sludge phosphorus capacity detection device according to the present invention has the beneficial effects that: the sludge from the sewage treatment plant is directly pumped into the mixing reaction device for phosphorus capacity detection, without other pretreatment processes, the operation is simple and fast, no additional chemicals need to be added, the cost is low, and the practicability is strong; by detecting the sludge concentration and phosphorus concentration of the sludge, the phosphorus capacity at a certain sludge concentration is calculated, so that the phosphorus removal ability of the sludge itself can be obtained, providing an intuitive data representation for the water plant to make full use of the phosphorus removal ability of the chemicals in the sludge. Furthermore, by changing the dosage of the phosphorus removal chemical, the sludge discharge amount and the sludge discharge method, etc., the physical and chemical phosphorus removal ability of the sludge is maximized, thereby reducing the dosage of chemicals and the sludge generation amount, and achieving energy conservation and consumption reduction.

[0035] Other features and advantages of the present invention will be described in detail in the following specific implementation manner. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] By describing the exemplary embodiments of the present invention in more detail in conjunction with the drawings, the above and other objects, features, and advantages of the present invention will become more obvious. Among them, in the exemplary embodiments of the present invention, the same reference numerals generally represent the same components.

[0037] Figure 1 Shows a schematic structural diagram of a sludge phosphorus capacity detection device according to an exemplary embodiment of the present invention;

[0038] Figure 2 Shows a curve graph of the change in sludge phosphorus content of a sludge phosphorus capacity detection device according to an exemplary embodiment of the present invention.

[0039] DESCRIPTION OF THE REFERENCE NUMERALS

[0040] 1. Sludge storage device, 11. Stirrer, 2. Phosphate solution storage device, 3. Mixing reaction device, 31. Reaction bottle, 32. Magnetic stirrer, 33. Sludge sampling tube, 34. Phosphate solution sampling tube, 4. Monitoring device, 41. Phosphate sampling tube, 42. Sludge concentration monitoring probe, 43. Dissolved oxygen monitoring probe, 44. Redox potential monitoring probe, 45. Filtering device, 46. Storage device sampling tube, 5. First delivery pump, 6. Second delivery pump, 7. First valve, 8. Second valve, 9. Controller, 10. Storage module. DETAILED DESCRIPTION OF THE INVENTION

[0041] The preferred embodiments of the present invention will be described in more detail below. Although the preferred embodiments of the present invention are described below, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to make the present invention more thorough and complete, and to fully convey the scope of the present invention to those skilled in the art.

[0042] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0043] To solve the problems existing in the prior art, as Figure 1 shown, the present invention provides a device for detecting the phosphorus capacity of sludge, including a sludge storage device 1, a phosphate solution storage device 2, a mixing reaction device 3, a monitoring device 4, and a controller 9;

[0044] Both the sludge storage device 1 and the phosphate solution storage device 2 are connected to the mixing reaction device 3. The sludge storage device 1 transports the sludge to be detected stored therein into the mixing reaction device 3 through a first delivery pump 5, and the phosphate solution storage device 2 transports the phosphate solution stored therein into the mixing reaction device 3 through a second delivery pump 6. The phosphate solution and the sludge to be detected are mixed and reacted to form a mixture;

[0045] The monitoring device 4 is used to monitor the phosphorus concentration and sludge concentration of the mixture in the mixing reaction device 3;

[0046] The controller 9 obtains the phosphorus capacity of the sludge to be detected according to the phosphorus concentration and sludge concentration.

[0047] The device for detecting the phosphorus capacity of sludge involved in the present invention directly pumps the sludge from the sewage treatment plant into the mixing reaction device for phosphorus capacity detection, without other pretreatment processes, is simple and fast to operate, does not require additional chemicals to be added, has low costs, and strong practicability; by detecting the sludge concentration and phosphorus concentration of the sludge, the phosphorus capacity at a certain sludge concentration is calculated and obtained, so that the phosphorus removal ability of the sludge itself can be obtained, providing an intuitive data representation for the water plant to make full use of the phosphorus removal ability of the chemicals in the sludge, and then maximizing the physical and chemical phosphorus removal ability of the sludge by changing the dosage of the phosphorus removal chemical, the sludge discharge amount and the sludge discharge method, etc., thereby reducing the chemical usage amount and the sludge generation amount, and achieving energy conservation and consumption reduction.

[0048] In this application, the mixing reaction device 3 includes a reaction flask 31 and a magnetic stirrer 32. The reaction flask 31 is placed on the magnetic stirrer 32. The reaction flask 31 is respectively connected to the sludge storage device 1 through a sludge sampling pipe 33 and to the phosphate solution storage device 2 through a phosphate solution sampling pipe 34. A first delivery pump 5 is provided on the sludge sampling pipe 33, and a second delivery pump 6 is provided on the phosphate solution sampling pipe 34;

[0049] The magnetic stirrer 32 is used to stir the mixture in the reaction flask 31. The magnetic stirrer 32 is an existing product, and its specific working principle will not be elaborated.

[0050] In an embodiment of this application, the reaction flask 31 is a cylindrical plexiglass container with a volume of 8 - 10 L. It is placed on the magnetic stirrer 32, and the magnetic stirrer 32 is used to stir the mixture in the reaction flask 31 so that the phosphate solution and the sludge to be detected can be fully mixed.

[0051] One end of the sludge sampling pipe 33 is provided on the side wall of the reaction flask 31, and the other end of the sludge sampling pipe 33 is provided in the middle of the sludge storage device 1;

[0052] One end of the phosphate solution sampling pipe 34 is provided on the top of the reaction flask 31, and the other end of the phosphate solution sampling pipe 34 is provided in the middle of the phosphate solution storage device 2;

[0053] A first valve 7 is provided on the sludge sampling pipe 33, and a second valve 8 is provided on the phosphate solution sampling pipe 34.

[0054] In an embodiment of this application, a stirrer 11 is provided inside the sludge storage device 1, and a drain opening is provided at the bottom. The volume of the sludge storage device 1 is 6 - 8 L. The stirrer 11 provided inside it is used to fully mix the sludge to be detected and avoid stratification. A first sampling port is provided in the middle, which is used to communicate with the other end of the sludge sampling pipe 33, and the drain opening is used to empty the sludge storage device 1.

[0055] In an embodiment of this application, the first delivery pump 5 can be a peristaltic pump, which is used to transport the sludge to be detected in the sludge storage device 1 into the reaction flask 31. The peristaltic pump can transport a predetermined volume, that is, a predetermined amount of sludge to be detected, into the reaction flask 31 by adjusting the output flow rate and presetting the time for calculation use.

[0056] In an embodiment of the present application, the volume of the phosphate solution storage device 2 is 2 - 5 L, which is used to hold the prepared phosphate solution, that is, the phosphate buffer solution. The concentration of the phosphate solution can be automatically determined as needed. A second sampling port is provided in the middle of the phosphate solution storage device 2, which is used to communicate with the other end of the phosphate solution sampling tube 34. The phosphate solution enters the mixing reaction device through the second sampling port and the second delivery pump 6 to react with the sludge to be detected. The first valve 7 and the second valve 8 are respectively used to control the on-off of the sludge sampling tube 33 and the phosphate solution sampling tube 34.

[0057] In an embodiment of the present application, a metering device is provided on the phosphate solution sampling tube 34, and / or,

[0058] The second delivery pump 6 is a metering pump, which is used to obtain the sampling volume of the phosphate solution for the mixing reaction.

[0059] In the present application, the monitoring device 4 includes a housing, a phosphate sampling tube 41, a sludge concentration monitoring probe 42, and a display screen, a phosphate detection reagent bottle, a photometer, and a processing module provided inside the housing;

[0060] One end of the phosphate sampling tube 41 is provided inside the reaction bottle 31, and the other end is communicated with the phosphate detection reagent bottle, and the mixture inside the reaction bottle 31 is transported to the phosphate detection reagent bottle through a pump for reaction. The photometer is used to measure the phosphorus concentration in the phosphate detection reagent bottle;

[0061] The sludge concentration monitoring probe 42 is provided inside the reaction bottle 31, which is used to detect the sludge concentration inside the reaction bottle 31;

[0062] The processing module is electrically connected to the photometer and the sludge concentration monitoring probe 42 respectively to obtain the phosphorus concentration and the sludge concentration;

[0063] The display screen displays the phosphorus concentration and the sludge concentration.

[0064] In an embodiment of the present application, the phosphate sampling tube 41 is inserted from above the reaction bottle 31, which is used to suck the phosphate solution inside the reaction bottle 31 through a pump and transport the phosphate solution to the phosphate detection reagent bottle through a pump. Phosphate detection reagent is provided in the phosphate detection reagent bottle. The phosphate solution reacts with the phosphate detection reagent, and the phosphorus concentration in the phosphate detection reagent bottle is measured by the photometer.

[0065] In an embodiment of the present application, the phosphate sampling tube 41 is communicated with the phosphate detection reagent bottle through a sampling pipeline. A filtering device 45 is provided on the sampling pipeline. The filtering device 45 is used to filter the particulate matter in the mixture inside the reaction bottle 31 to prevent the suspended matter from interfering with the detection result of phosphate. The filtering device 45 includes a filter element (not shown), and the pore diameter of the filter element is 0.45 μm, which can be replaced regularly to maintain the filtering effect.

[0066] This phosphate detection reagent bottle is the first phosphate detection reagent bottle.

[0067] In an embodiment of the present application, it further includes a storage device sampling tube 46 and a second phosphate detection reagent bottle. One end of the storage device sampling tube 46 is inserted into the interior from above the phosphate solution storage device 2, and the other end is connected to the second phosphate detection reagent bottle through a pump. The storage device sampling tube 46 is used to monitor the phosphate concentration in the phosphate solution storage device 2, extract the phosphate solution in the phosphate solution storage device 2 into the second phosphate detection reagent bottle for reaction, and measure the phosphorus concentration in the second phosphate detection reagent bottle through a photometer. During the detection process, the phosphate solution concentration in the phosphate solution storage device 2 can be detected at preset time intervals. When the concentration in the phosphate solution storage device 2 decreases significantly, the phosphate solution can be reconfigured or supplemented.

[0068] The photometer is an existing product, and the process of reacting the phosphate solution with the phosphate detection reagent and measuring the phosphorus concentration is an existing technology, and the specific principle will not be elaborated here.

[0069] In an embodiment of the present application, the housing of the monitoring device 4 is provided with a water inlet and a water outlet. The water inlet is used to communicate with the phosphate sampling tube 41 and the storage device sampling tube 46 respectively, and the water outlet is used to discharge the liquids in the first phosphate detection reagent bottle and the second phosphate detection reagent bottle respectively.

[0070] In an embodiment of the present application, the monitoring device 4 further includes a dissolved oxygen monitoring probe 43 and a redox potential monitoring probe 44. The dissolved oxygen monitoring probe 43 and the redox potential monitoring probe 44 are both inserted into the reaction flask 31 and electrically connected to the processing module. The processing module respectively obtains the dissolved oxygen concentration and the redox potential detected by the dissolved oxygen monitoring probe 43 and the redox potential monitoring probe 44.

[0071] When the phosphate solution reacts with the sludge to be detected, the dissolved oxygen and redox potential of the mixture will change. Too high dissolved oxygen will cause biological phosphorus uptake, and the higher the stirring speed of the magnetic stirrer 32, the higher the generated dissolved oxygen and the higher the redox potential, which is likely to cause biological interference with the detection result. Therefore, it is necessary to monitor the dissolved oxygen concentration and redox potential in real time to regulate the stirring speed of the magnetic stirrer 32.

[0072] The controller 9 receives the phosphorus concentration, sludge concentration, dissolved oxygen concentration, and redox potential transmitted by the processing module;

[0073] When the dissolved oxygen concentration is higher than the first concentration threshold and the redox potential is greater than the first potential threshold, the controller 9 controls the stirring speed of the magnetic stirrer 32 to decrease to prevent biological aerobic phosphorus uptake from interfering with the detection result;

[0074] When the dissolved oxygen concentration is lower than the second concentration threshold and the oxidation-reduction potential is less than the second potential threshold, the controller 9 controls the stirring speed of the magnetic stirrer 32 to increase, preventing the occurrence of biological anaerobic phosphorus release from interfering with the detection results;

[0075] When the growth rate of the phosphorus concentration is greater than the third concentration threshold, the mixing reaction of the mixture in the reaction flask 31 ends, and the controller 9 controls the second delivery pump 6 to close.

[0076] In an embodiment of the present application, the first concentration threshold of the dissolved oxygen concentration is 2 mg / L, and the second concentration threshold is 0 mg / L; the first potential threshold of the oxidation-reduction potential is 100 mV, and the second potential threshold is -200 mV; when the phosphorus concentration in the reaction flask 31 detected by the photometer rises rapidly and at least two consecutive values increase in multiples, it can be considered that the mixing reaction ends. At this time, the phosphorus absorption capacity of the sludge in the reaction flask 31, that is, the phosphorus capacity, has reached a saturated state.

[0077] In the present application, the detection device further includes a storage module 10; the controller 9 is communicatively connected to the processing module, and is electrically connected to the magnetic stirrer 32 and the second delivery pump 6, and is also electrically connected to the first delivery pump 5, the first valve 7, and the second valve 8;

[0078] The storage module 10 is used to store data such as phosphorus concentration, sludge concentration, dissolved oxygen concentration, oxidation-reduction potential, and operating time.

[0079] In the present application, the controller 9 calculates the phosphorus capacity absorbed by the sludge per unit volume according to the following formula:

[0080] Phosphorus capacity = (phosphate solution injection volume / 1000 + sludge volume) * phosphorus concentration reduction amount / (phosphate solution injection volume / 1000 + sludge volume) * (sludge concentration / 1000), where,

[0081] The phosphorus concentration reduction amount represents the difference between the phosphorus concentration before the mixing reaction starts and the phosphorus concentration after the mixing reaction ends;

[0082] The sludge volume represents the volume of the sludge to be detected transported into the reaction flask 31 by the first delivery pump 5, which can be obtained by multiplying the delivery volume of the first delivery pump 5 by the delivery time, or can be directly obtained by setting a metering device at the first delivery pump 5.

[0083] The above calculation process can be quickly calculated through pre-designed computer instructions to evaluate the physical and chemical phosphorus removal ability of the sludge, and finally obtain the relationship between the phosphorus capacity, phosphorus concentration, MLSS, and the dosage of phosphorus removal agents in the water plant, providing an intuitive data representation for the water plant to make full use of the phosphorus removal ability of the chemical agents in the sludge.

[0084] The detection device of the present application directly pumps the sludge from the sewage treatment plant into the mixing reaction device for phosphorus capacity detection after stirring, without other pretreatment processes, with simple and fast operation, no need to add additional chemicals, low cost, and very strong practicability; through the controller and computer instructions, the phosphorus capacity of the sludge to be detected can be quickly calculated to evaluate the physical and chemical phosphorus removal ability of the sludge, and finally the relationship between the phosphorus capacity, phosphorus concentration, MLSS, and the dosage of phosphorus removal chemicals in the water plant can be obtained, providing an intuitive data representation for the water plant to make full use of the phosphorus removal ability of the chemicals in the sludge; it can not only detect the phosphorus capacity of the sludge in the sewage treatment plant, but also detect the aluminum-containing sludge in the water supply plant, with very wide applicability.

[0085] Example 1

[0086] Take the sludge of a certain sewage treatment plant as the object for phosphorus capacity detection. The phosphorus concentration in the supernatant of the sludge is 0.1 mg / L, that is, the sludge in a unit volume (L) absorbs 0.1 mg of phosphorus. After the sample is retrieved, it is placed in the sludge storage device 1, and the stirrer 11 is turned on to fully mix the sludge to prevent sludge stratification;

[0087] Prepare a phosphate solution with a concentration of 5 g / L and place it in the phosphate solution storage device 2. The concentration of phosphate is detected every 30 minutes through the sampling tube 46 of the storage device and the second phosphate detection reagent bottle. If the phosphate concentration in the phosphate solution storage device 2 decreases significantly, the solution needs to be re-prepared;

[0088] Open the first valve 7 and the first delivery pump 5, control the flow rate of the first delivery pump 5 to be 500 mL / min, and set the time to 4 minutes so that the sludge in the reaction flask 31 is 2 L, which is used as the sludge volume for detection. After the first delivery pump 5 reaches the set time, it automatically shuts down, or the controller 9 controls the first valve 7 and the first delivery pump 5 to close;

[0089] When the sludge in the reaction flask 31 reaches 2 L, the controller 9 controls the magnetic stirrer 32 to start, and the rotation speed is regulated according to the dissolved oxygen concentration (DO) detected by the dissolved oxygen monitoring probe 43 and the oxidation-reduction potential (ORP) detected by the oxidation-reduction potential monitoring probe 44. When DO is greater than 2 mg / L and ORP is greater than 100 mV, the controller 9 controls to reduce the stirring speed of the magnetic stirrer 32. When the DO concentration is lower than 0 mg / L and ORP is less than -200 mV, the controller 9 increases the stirring speed of the magnetic stirrer 32. According to operation experience, the rotation speed of the magnetic stirrer 32 is controlled at 500 - 1000 r / min; at the same time, open the second valve 8 and the second delivery pump 6 on the phosphate solution inlet pipe 34. The second delivery pump 6 is a metering pump, and the flow rate of the metering pump is set to 10 mL / min and runs continuously. In addition, the controller controls the pump to sample and detect the phosphate concentration in the phosphate solution storage device 2 every 5 minutes through the storage device sampling tube 46;

[0090] The controller 9 controls the opening and closing of the metering pump according to the detected phosphorus concentration value. When the phosphorus concentration detected by sampling the phosphate sampling pipe 41 is higher than 25 mg / L and three consecutive values increase in multiples, the metering pump is closed. At this time, the phosphorus removal capacity of the sludge in the reaction flask 31 reaches the saturation state. At the same time, the sludge concentration monitoring probe 42 detects the sludge concentration (MLSS) in the reaction flask 31 to complete the detection process;

[0091] The controller 9 calculates the phosphorus capacity of the sludge based on the phosphorus concentration, metering pump flow rate, and running time (to obtain the phosphate solution injection volume), sludge concentration, sludge volume, etc.

[0092] Phosphorus capacity = (phosphate solution injection volume / 1000 + sludge volume) * phosphorus concentration reduction amount / (phosphate solution injection volume / 1000 + sludge volume) * (sludge concentration / 1000)

[0093] Repeat the detection process three times and take the average value. The specific results are shown in Table 1 below and the phosphorus capacity curve graph as Figure 2 shown.

[0094] Table 1 Sludge phosphorus capacity detection data

[0095]

[0096] According to the detection results, the average phosphorus capacity of the three detections is 2.89 mgP / gMLSS, indicating that the amount of phosphorus that can be removed by each cubic meter of sludge return when the sludge concentration MLSS of this water plant is 8227 mg / L is 2.89 * 8227 / 1000 = 23.77 mg, which is equivalent to adding 970 mg of aluminum sulfate phosphorus removal agent with 6% effective content (23.77 * 2.45 / 0.06). Among them, 2.45 means that 2.45 mg of aluminum sulfate phosphorus removal agent is required to remove 1 mg of phosphorus.

[0097] Based on the actual water volume of the water plant for accounting, the daily influent water volume of the water plant is 200,000 cubic meters, and the reflux ratio is 1:1. Then the amount of phosphorus that can be removed by sludge return is 4.75 tons, which is equivalent to adding 194 tons of aluminum sulfate phosphorus removal agent with 6% effective content. The daily aluminum sulfate dosage of the water plant is 30 tons. Therefore, the sludge phosphorus capacity detected in this batch can maintain the phosphorus removal capacity of the water plant for 6 days, that is, no additional aluminum sulfate phosphorus removal agent needs to be added within 6 days, greatly saving the chemical agent cost.

[0098] Using this detection method is fast, and through the phosphorus capacity data, the water plant can change the phosphorus removal agent dosing strategy according to the daily sludge concentration. In addition, the sludge retention time can also be adjusted by the sludge discharge amount to give full play to the phosphorus removal efficiency of the chemical agent in the sludge.

[0099] The embodiments of the present invention have been described above. The above description is exemplary and not exhaustive, and is also not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments.

Claims

1. Application of a detection device in detecting the phosphorus capacity of sludge, characterized in that, The sludge phosphorus capacity detection device includes a sludge storage device (1), a phosphate solution storage device (2), a mixing reaction device (3), a monitoring device (4) and a controller (9); The sludge storage device (1) and the phosphate solution storage device (2) are both connected to the mixing reaction device (3). The sludge storage device (1) transports the sludge to be detected stored therein into the mixing reaction device (3) through a first delivery pump (5), and the phosphate solution storage device (2) transports the phosphate solution stored therein into the mixing reaction device (3) through a second delivery pump (6). The phosphate solution and the sludge to be detected are mixed and reacted to form a mixture; The monitoring device (4) is used to monitor the phosphorus concentration and sludge concentration of the mixture in the mixing reaction device (3); The controller (9) obtains the phosphorus capacity of the sludge to be detected according to the phosphorus concentration and the sludge concentration; The mixing reaction device (3) includes a reaction bottle (31) and a magnetic stirrer (32). The reaction bottle (31) is placed on the magnetic stirrer (32). The reaction bottle (31) is respectively connected to the sludge storage device (1) through a sludge sampling tube (33) and to the phosphate solution storage device (2) through a phosphate solution sampling tube (34). The first delivery pump (5) is arranged on the sludge sampling tube (33), and the second delivery pump (6) is arranged on the phosphate solution sampling tube (34); The magnetic stirrer (32) is used to stir the mixture in the reaction bottle (31); The controller (9) calculates the phosphorus capacity absorbed by the sludge per unit volume according to the following formula: Phosphorus capacity = (phosphate solution injection volume / 1000 + sludge volume) * phosphorus concentration reduction amount / (phosphate solution injection volume / 1000 + sludge volume) * (sludge concentration / 1000), where The phosphorus concentration reduction amount represents the difference between the phosphorus concentration before the start of the mixing reaction and the phosphorus concentration after the end of the mixing reaction; The sludge volume represents the volume of the sludge to be detected transported into the reaction bottle (31) through the first delivery pump (5); The sludge volume is obtained by multiplying the delivery volume of the first delivery pump (5) by the delivery time, or directly obtained by setting a metering device at the first delivery pump (5); The monitoring device (4) includes a housing, a phosphate sampling tube (41), a sludge concentration monitoring probe (42), and a display screen, a phosphate detection reagent bottle, a photometer and a processing module arranged in the housing; One end of the phosphate sampling tube (41) is arranged in the reaction bottle (31), and the other end is connected to the phosphate detection reagent bottle, and the mixture in the reaction bottle (31) is transported into the phosphate detection reagent bottle for reaction through a pump. The photometer is used to measure the phosphorus concentration in the phosphate detection reagent bottle; The sludge concentration monitoring probe (42) is arranged in the reaction bottle (31) and is used to detect the sludge concentration in the reaction bottle (31); The processing module is electrically connected to the photometer and the sludge concentration monitoring probe (42) respectively to obtain the phosphorus concentration and the sludge concentration; The display screen displays the phosphorus concentration and the sludge concentration; the monitoring device (4) further includes a dissolved oxygen monitoring probe (43) and a redox potential monitoring probe (44). The dissolved oxygen monitoring probe (43) and the redox potential monitoring probe (44) are both inserted into the reaction flask (31) and are electrically connected to the processing module. The processing module respectively obtains the dissolved oxygen concentration and the redox potential detected by the dissolved oxygen monitoring probe (43) and the redox potential monitoring probe (44); The detection device further includes a storage module (10); the controller (9) is communicatively connected to the processing module and is electrically connected to the magnetic stirrer (32) and the second delivery pump (6); The storage module (10) is used to store the phosphorus concentration, the sludge concentration, the dissolved oxygen concentration and the redox potential; The controller (9) receives the phosphorus concentration, the sludge concentration, the dissolved oxygen concentration and the redox potential transmitted by the processing module; When the dissolved oxygen concentration is higher than the first concentration threshold and the redox potential is greater than the first potential threshold, the controller (9) controls the stirring speed of the magnetic stirrer (32) to decrease; When the dissolved oxygen concentration is lower than the second concentration threshold and the redox potential is less than the second potential threshold, the controller (9) controls the stirring speed of the magnetic stirrer (32) to increase; When the growth rate of the phosphorus concentration is greater than the third concentration threshold, the mixing reaction of the mixture in the reaction flask (31) ends, and the controller (9) controls the second delivery pump (6) to close; A metering device is provided on the phosphate solution sampling tube (34), and / or The second delivery pump (6) is a metering pump for obtaining the sampling amount of the phosphate solution for the mixing reaction; The controller (9) calculates the phosphorus capacity absorbed by the sludge per unit volume according to the following formula: Phosphorus capacity = (phosphate solution sampling amount / 1000 + sludge amount) * phosphorus concentration reduction amount / (phosphate solution sampling amount / 1000 + sludge amount) * (sludge concentration / 1000), where The phosphorus concentration reduction amount represents the difference between the phosphorus concentration before the start of the mixing reaction and the phosphorus concentration after the end of the mixing reaction; The sludge amount represents the volume of the sludge to be detected transported into the reaction flask (31) by the first delivery pump (5).

2. Use of the detection device according to claim 1 in detecting the phosphorus capacity of sludge, characterized in that, One end of the sludge sampling tube (33) is provided on the side wall of the reaction flask (31), and the other end of the sludge sampling tube (33) is provided in the middle of the sludge storage device (1); One end of the phosphate solution sampling tube (34) is provided on the top of the reaction flask (31), and the other end of the phosphate solution sampling tube (34) is provided in the middle of the phosphate solution storage device (2); A first valve (7) is provided on the sludge sampling tube (33), and a second valve (8) is provided on the phosphate solution sampling tube (34).

3. Use of the detection device according to claim 1 in detecting the phosphorus capacity of sludge, characterized in that The phosphate sampling tube (41) is communicated with the phosphate detection reagent bottle through a sampling pipeline, and a filtering device (45) is arranged on the sampling pipeline.

4. Use of the detection device according to claim 1 in detecting the phosphorus capacity of sludge, characterized in that, A stirrer (11) is arranged in the sludge storage device (1), and an emptying port is arranged at the bottom.

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