Equipment and method for rapid evaluation of the effectiveness of external carbon sources in sewage treatment plants

Abstract

A device for quickly evaluating the effectiveness of an added carbon source in a sewage treatment plant, including a constant temperature water bath system, a main reaction system and a detection and control system. No special person is required to be on duty during the operation of the equipment. The temperature is regulated, various data are measured online and automatically judged through the control module control system, and performance warnings and process adjustment suggestions are provided to the operator, which is highly efficient. At the same time, the structure is simple, the size is small, space is saved, the operation is simple, and maintenance is easy. The method for quickly evaluating the effectiveness of an added carbon source in a sewage treatment plant of the present invention introduces a new indicator for evaluating sludge activity, namely the activated sludge index κ. Compared with the previous oxygen consumption rate and specific oxygen consumption rate, the measurement result of the sludge activity index reduces the measurement error. The method and device described in this patent can quickly and directly measure the effectiveness of an added carbon source for sewage treatment, so that sewage treatment operators can timely regulate the operating status of the sewage treatment system.

Description

Technical Field

[0001] The invention relates to the technical field of sewage treatment, and in particular to a device and a method for quickly evaluating the effectiveness of an added carbon source in a sewage treatment plant. Background Art

[0002] The sewage accepted by domestic sewage treatment plants generally has a low C / N ratio, which leads to the inability of the carbon source to meet the demand in the denitrification process of the activated sludge treatment method. The denitrification and phosphorus removal processes are restricted. In the actual operation of the sewage treatment plant, external carbon sources are usually required to supplement it.

[0003] At present, the terminal effluent of sewage treatment plants is generally used as an evaluation index for the quality of carbon sources in production. However, the residence time of sewage in sewage treatment plants is generally long (generally more than 1 day), and the sewage treatment process is relatively complex in actual working conditions. There are many factors that affect the water quality of terminal effluent. Changes in various control parameters and external factors will affect the effluent quality. Therefore, relying solely on the terminal effluent quality to reflect the effectiveness of the carbon source not only has a lag, but the reference significance of the test results for the evaluation of the effectiveness of the carbon source is also limited. Therefore, the shorter the evaluation method of the effectiveness of the carbon source is, and the more direct the response to the activity of the activated sludge is, the greater its significance for production operation.

[0004] The methods in the prior art often evaluate the effectiveness of carbon sources through instrumental testing. However, the carbon source substances used in actual production are generally industrial by-products, which have more than one effective component and unstable content, and often contain substances that are toxic and harmful to activated sludge. These components are often unknown, and these substances may have an impact on the stability of the sewage treatment process. Instrumental testing can generally only quantify the content of carbon source substances through chemical analysis methods for a certain type or class of substances, but the cost of testing carbon source components with unknown content is high and the test results often cannot fully and timely reflect the effectiveness of the target carbon source.

[0005] The sludge activity in the target process is the most direct and fastest method to evaluate the carbon source. It has been reported in the literature that the oxygen consumption rate (OUR) of biologically activated sludge can be used to evaluate the effectiveness of the carbon source. At present, the determination methods of OUR are mostly extensive and do not consider the influence of temperature on the measurement results. In fact, for every 1°C increase in temperature, the metabolic activity of microorganisms will increase by about 12%. The detection time in the OUR comparison experiment is often longer, and changes in ambient temperature often have a greater impact on sludge activity. The measurement results of OUR cannot truly reflect the effectiveness of the carbon source. In addition, in the traditional calculation of OUR, two points are usually selected on the dissolved oxygen decay curve to calculate the slope of the straight line where the two points are located. This calculation method is greatly affected by the selection of calculation points, and the calculation results of different points are quite different. The sludge oxygen consumption rate measurement method is:

[0006] and

[0007] However, the measurement and calculation methods of sludge oxygen consumption rate and specific oxygen consumption rate (SOUR) reported in previous studies are generally expressed as the ratio of the amount of dissolved oxygen consumed by microorganisms in the activated sludge to the time:

[0008]

[0009] from Figure 1 It can be seen that the numerical meanings are different. In the traditional calculation process, two points are usually selected on the dissolved oxygen decay curve to calculate the slope of the straight line where the two points are located. This calculation method is greatly affected by the selection of the measurement points, such as Figure 1 Among them, K1 corresponds to (t1, Y2) and (t2, Y1), K2 corresponds to (t1, Y2) and (t`2, Y`1), and K3 corresponds to (t`1, Y`2) and (t`2, Y`1). The calculation results of different points are quite different.

[0010] In the prior art, specific oxygen consumption rate (SOUR) is also used to evaluate the effectiveness of carbon sources. However, SOUR reflects the activity change trend of a single living microorganism in activated sludge. This detection method ignores the effect of sludge concentration on the response results. In addition, since the sludge concentration in each process section is often unstable, the MLSS measurement results of individual points cannot reflect the overall status of the activated sludge process, and the detection results often have large errors. Summary of the invention

[0011] In order to overcome the deficiencies in the background technology, the present invention discloses a device and a method for rapidly evaluating the effectiveness of an added carbon source in a sewage treatment plant.

[0012] In order to achieve the above-mentioned invention object, the present invention adopts the following technical scheme:

[0013] The device for rapidly evaluating the effectiveness of an added carbon source in a sewage treatment plant of the present invention comprises a constant temperature water bath system, a main reaction system and a detection and control system; wherein the constant temperature water bath system comprises a constant temperature water bath, a water bath heater, a temperature measuring electrode, a flow circulation pump and an electromagnetic stirrer, the constant temperature water bath forms a container for water bath heating, the water bath heater, the temperature measuring electrode and the flow circulation pump are arranged in the constant temperature water bath, and a plurality of electromagnetic stirrers are arranged outside the constant temperature water bath; the main reaction system comprises a pre-reaction bottle and a reaction bottle, the reaction bottles are multiple, the pre-reaction bottle and the reaction bottle are placed in the constant temperature water bath when working, and the position is the same as that of the electromagnetic stirrer. Corresponding to the magnetic stirrer, stirrers are respectively arranged in the pre-reaction bottle and the reaction bottle, the pre-reaction bottle is also provided with a gas distributor, the gas distributor is connected to the external explosion pump through a pipeline, and dissolved oxygen electrodes are respectively arranged in the corresponding pre-reaction bottle and the reaction bottle; the detection control system includes a control module and an interactive display device, the control module is respectively connected with the water bath heater, the temperature measuring electrode, the flow circulation pump, the electromagnetic stirrer, the dissolved oxygen electrode and the interactive display module, the control module controls the operation of each component and performs data processing, and the interactive display module enables the operator to input control information of the equipment and display the detection results.

[0014] This technical solution can also adopt the following technical measures:

[0015] A reaction bottle limiting plate is arranged in the constant temperature water bath, and a plurality of limiting holes are arranged on the reaction bottle limiting plate, and the limiting holes correspond to the positions of the electromagnetic stirrer one by one.

[0016] The pre-reaction bottle and the reaction bottle respectively comprise a threaded bottle cap and a screw-mouth glass bottle body, and the dissolved oxygen electrodes are respectively arranged on each threaded bottle cap.

[0017] The constant temperature water bath comprises a tank body and a heat-insulating cover, and the heat-insulating cover is combined with the tank body to form a water bath space inside.

[0018] The ratio of the volume of the pre-reaction bottle to the volume of a single reaction bottle is (6-10):1.

[0019] The method for rapidly evaluating the effectiveness of an external carbon source in a sewage treatment plant of the present invention comprises the following steps: selecting a standard carbon source, converting subsequent test results into an equivalent value of the standard carbon source, and evaluating the effectiveness of the carbon source to be tested by using the equivalent value; using a sludge activity index κ to characterize the change trend of sludge activity, and the numerical meaning of the sludge activity index κ is the product of the inverse of the integral of the dissolved oxygen saturation decay curve and time and the activated sludge constant, that is:

[0020]

[0021] Where f(t) is the decay function of dissolved oxygen saturation over time, sludge activity constant N0 = 1000-100000,

[0022] Y2=f(t1)=50%~100%, Y1=f(t2)=0%~50%.

[0023] The method for rapidly evaluating the effectiveness of an added carbon source in a sewage treatment plant of the present invention comprises the following steps:

[0024] A. Set the integration step size t through the interactive display module s , sludge activity constant N0, set values ​​Y1, Y2, set target dissolved oxygen value DO0, set temperature value T0, aeration step length t1, temperature control step length t2, set dissolved oxygen values ​​DO1, DO2;

[0025] B. Start the equipment through the interactive display module, and the water bath heater and flow circulation pump start running respectively;

[0026] C. Take the sludge from the aerobic pool and add it to the pre-reaction bottle until it reaches 75-85% of the total volume of the pre-reaction bottle;

[0027] D. Place the pre-reaction bottle in a constant temperature water bath, the bottom position of the pre-reaction bottle corresponds to the electromagnetic stirrer, a stirrer is placed in the pre-reaction bottle, the electromagnetic stirrer is started and drives the stirrer to stir the sludge in the pre-reaction bottle;

[0028] E. The aeration pump is started, and the aeration step time is t1. The dissolved oxygen content in the pre-reaction bottle is controlled at the dissolved oxygen value DO0 through the dissolved oxygen electrode and the aeration pump; the water bath heater is started, and the temperature control step time is t2. The water bath temperature in the water bath reaction tank is controlled at the set temperature value T0 through the temperature measuring electrode and the water bath heater;

[0029] F. Stop aeration when the liquid in the pre-reaction bottle meets the following conditions at the same time: the temperature is T0±0.5℃, and the dissolved oxygen value reaches the set value DO0±2%;

[0030] G. Dispense the liquid in the pre-reaction bottle into each reaction bottle in equal amounts, and place a stirring bar in each reaction bottle. Start the electromagnetic stirrer and drive the stirring bar to stir the liquid in the reaction bottle;

[0031] H. Add a standard carbon source liquid into a reaction bottle as a standard reaction bottle, and add the same volume of the carbon source liquid to be tested into other reaction bottles;

[0032] I. The control module determines whether the dissolved oxygen value DO in each reaction bottle reaches the set value DO1 through the dissolved oxygen electrode detection, records the time t0 when the dissolved oxygen electrode detection value reaches DO1, and records the dissolved oxygen value DO after t0;

[0033] K, according to the integration step t s Calculate the integrated area and display the dissolved oxygen decay curve in the interactive display module;

[0034] L. The control module determines whether the dissolved oxygen value DO in each reaction bottle reaches the set value DO2 through the dissolved oxygen electrode detection, and stops the integral calculation after reaching DO2;

[0035] M. Arrange the results in each reaction bottle according to the κ value, and display the sorting results through an interactive display module;

[0036] N. Store the integrated area, κ value and dissolved oxygen decay curve corresponding to each reaction bottle.

[0037] Due to the adoption of the above-mentioned technical solution, the present invention has the following beneficial effects:

[0038] The device for quickly evaluating the effectiveness of an added carbon source in a sewage treatment plant of the present invention includes a constant temperature water bath system, a main reaction system and a detection control system. No special person is required to be on duty during the operation of the equipment. The temperature regulation, online measurement and automatic judgment of various data are realized through the control module control system, and effectiveness warnings and process adjustment suggestions are provided to the operator, which is highly efficient. At the same time, the structure is simple, the size is small, space-saving, easy to operate and maintain. The method for quickly evaluating the effectiveness of an added carbon source in a sewage treatment plant of the present invention introduces a new indicator for evaluating sludge activity, namely the activated sludge index κ. Compared with the previous oxygen consumption rate and specific oxygen consumption rate, the measurement result of the sludge activity index reduces the measurement error. The method and device described in this patent can quickly and directly measure the effectiveness of the added carbon source for sewage treatment, so that the sewage treatment operator can timely regulate the operating status of the sewage treatment system. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a schematic diagram of the results of the method for evaluating the effectiveness of an added carbon source by oxygen consumption rate in the prior art;

[0040] Figure 2 A schematic diagram of the structure of the device for rapidly evaluating the effectiveness of an external carbon source in a sewage treatment plant according to the present invention

[0041] Figure 3 This is a schematic diagram of the structure of the pre-reaction bottle in the device for rapidly evaluating the effectiveness of an added carbon source in a sewage treatment plant according to the present invention;

[0042] Figure 4 This is a schematic diagram of the structure of the reaction bottle in the device for rapidly evaluating the effectiveness of an added carbon source in a sewage treatment plant according to the present invention;

[0043] Figure 5 A flow chart of the method for rapidly evaluating the effectiveness of an added carbon source in a sewage treatment plant according to the present invention;

[0044] Figure 6 A schematic diagram of a dissolved oxygen decay curve in the method for rapidly evaluating the effectiveness of an added carbon source in a sewage treatment plant according to the present invention;

[0045] Figure 7 This is a schematic diagram of the experimental results of the standard reaction bottle in the first embodiment of the present invention;

[0046] Figure 8 This is a schematic diagram of the experimental results of adding the first sample to the reaction bottle in the first embodiment of the present invention;

[0047] Fig. 9 This is a schematic diagram of the experimental results of adding a second sample to a reaction bottle in the first embodiment of the present invention;

[0048] Fig.10 This is a schematic diagram of the experimental results of adding a third sample to a reaction bottle in the first embodiment of the present invention;

[0049] Fig.11 This is a schematic diagram of the experimental results of the standard reaction bottle in the second embodiment of the present invention;

[0050] Fig.12 This is a schematic diagram of the experimental results of adding the first sample to the reaction bottle in the second embodiment of the present invention;

[0051] Fig.13 This is a schematic diagram of the experimental results of adding a second sample to a reaction bottle in the second embodiment of the present invention;

[0052] Fig.14 This is a schematic diagram of the experimental results of adding the third sample to the reaction bottle in the second embodiment of the present invention. DETAILED DESCRIPTION

[0053] The present invention can be explained in detail by the following examples, and the purpose of disclosing the present invention is to protect all technical improvements within the scope of the present invention.

[0054] like Figures 2 to 4As shown, the device for quickly evaluating the effectiveness of an added carbon source in a sewage treatment plant of the present invention comprises a constant temperature water bath system, a main reaction system and a detection and control system; wherein the constant temperature water bath system comprises a constant temperature water bath 1, a water bath heater 3, a temperature measuring electrode 11, a flow circulation pump 4 and an electromagnetic stirrer 2, the constant temperature water bath forms a container for water bath heating, the water bath heater, the temperature measuring electrode and the flow circulation pump are arranged in the constant temperature water bath, the flow circulation pump can ensure that the water in the water bath can flow, and keep the temperature at each position quickly balanced, and a plurality of electromagnetic stirrers are arranged outside the constant temperature water bath; the main reaction system comprises a pre-reaction bottle 12 and a reaction bottle 6, and according to the number of test samples, there are multiple reaction bottles, and the pre-reaction bottle is The reaction bottle and the pre-reaction bottle are placed in a constant temperature water bath when working, and the position corresponds to the electromagnetic stirrer 2. A stirrer 10 is respectively arranged in the pre-reaction bottle and the reaction bottle. The pre-reaction bottle is also provided with a gas distributor 14. The gas distributor is annular and is connected to an external explosion pump 13 through a pipeline. Dissolved oxygen electrodes 7 are respectively arranged in the corresponding pre-reaction bottle and the reaction bottle; the detection control system includes a control module and an interactive display device 9. The control module is respectively connected to the water bath heater, the temperature measuring electrode, the flow circulation pump, the electromagnetic stirrer, the dissolved oxygen electrode and the interactive display module. The control module controls the operation of each component and performs data processing. The interactive display module enables the operator to input control information of the equipment and display the detection results.

[0055] The constant temperature water bath adopts curved pool wall, which can form vortex water flow, help to reduce dead corners in the pool and ensure uniform and stable temperature in the pool.

[0056] A reaction bottle limiting plate 5 is arranged in the constant temperature water bath, and a plurality of limiting holes are arranged on the reaction bottle limiting plate. When in use, the limiting plate is fixed in the constant temperature water bath at a constant temperature. Each limiting hole corresponds to the position of the electromagnetic stirrer one by one. After the reaction bottles are respectively placed in the limiting holes, it can be ensured that the stirrer in the reaction bottles can be driven by the electromagnetic stirrer.

[0057] The pre-reaction bottle and the reaction bottle respectively include a threaded bottle cap and a screw-mouth glass bottle body, and the dissolved oxygen electrode 7 is respectively arranged on each threaded bottle cap, which improves the convenience of operation. There is no need to perform a separate step of placing the dissolved oxygen electrode, and only the threaded bottle cap and the screw-mouth glass bottle body need to be matched.

[0058] The constant temperature water bath includes a tank body and a thermal insulation cover. The thermal insulation cover is combined with the tank body to form a water bath space inside. During testing, the thermal insulation cover can be combined and sealed with the tank body to maintain a constant temperature in the constant temperature water bath and avoid interference from the outside.

[0059] The ratio of the volume of the pre-reaction bottle to the volume of a single reaction bottle is (6-10):1, so as to ensure that the liquid in the pre-reaction bottle can be divided into a plurality of different reaction bottles for comparison and reference.

[0060] like Figure 5 , Figure 6 As shown, the method for quickly evaluating the effectiveness of an added carbon source in a sewage treatment plant of the present invention selects a standard carbon source, and the subsequent test results are converted into an equivalent value of the standard carbon source, and the effectiveness of the carbon source to be tested is evaluated by the equivalent value; the sludge activity index κ is used to characterize the change trend of sludge activity, and the numerical meaning of the sludge activity index κ is the product of the inverse of the integral of the dissolved oxygen saturation decay curve and time and the activated sludge constant, that is:

[0061]

[0062] Wherein f(t) is the decay function of dissolved oxygen saturation with time, sludge activity constant N0=1000-100000, Y2=f(t1)=50%~100%, Y1=f(t2)=0%~50%.

[0063] Dissolved oxygen saturation refers to the percentage of dissolved oxygen in water under certain temperature conditions to the saturated dissolved oxygen in distilled water at that temperature.

[0064] The method for rapidly evaluating the effectiveness of an added carbon source in a sewage treatment plant of the present invention comprises the following steps:

[0065] A. Set the integration step size t through the interactive display module s , sludge activity constant N0, set values ​​Y1, Y2, set target dissolved oxygen value DO0, set temperature value T0, aeration step length t1, temperature control step length t2, set dissolved oxygen values ​​DO1, DO2;

[0066] B. Start the equipment through the interactive display module, and the water bath heater and flow circulation pump start running respectively;

[0067] C. Take the aerobic pool sludge and add it to the pre-reaction bottle until it reaches 75-85% of the total volume of the pre-reaction bottle; the aerobic pool sludge is the mud-water mixture discharged from the end of the aerobic pool of the sewage treatment plant;

[0068] D. Place the pre-reaction bottle in a constant temperature water bath, the bottom position of the pre-reaction bottle corresponds to the electromagnetic stirrer, a stirrer is placed in the pre-reaction bottle, the electromagnetic stirrer is started and drives the stirrer to stir the sludge in the pre-reaction bottle;

[0069] E. The aeration pump is started, and the aeration step time is t1. The dissolved oxygen content in the pre-reaction bottle is controlled at the dissolved oxygen value DO0 through the dissolved oxygen electrode and the aeration pump; the water bath heater is started, and the temperature control step time is t2. The water bath temperature in the water bath reaction tank is controlled at the set temperature value T0 through the temperature measuring electrode and the water bath heater;

[0070] F. Stop aeration when the liquid in the pre-reaction bottle meets the following conditions at the same time: the temperature is T0±0.5℃, and the dissolved oxygen value reaches the set value DO0±2%;

[0071] G. Dispense the liquid in the pre-reaction bottle into each reaction bottle in equal amounts, and place a stirring bar in each reaction bottle. Start the electromagnetic stirrer and drive the stirring bar to stir the liquid in the reaction bottle;

[0072] H. Add a standard carbon source liquid into a reaction bottle as a standard reaction bottle, and add the same volume of the carbon source liquid to be tested into other reaction bottles;

[0073] I. Turn on the water bath heater, the temperature control step time is t2, and the water bath temperature in the water bath reaction tank is controlled at the set temperature value T0 through the temperature measuring electrode and the water bath heater;

[0074] J. The control module determines whether the dissolved oxygen value DO in each reaction bottle reaches the set value DO1 through the dissolved oxygen electrode detection, records the time t0 when the dissolved oxygen electrode detection value reaches DO1, and records the dissolved oxygen value DO after t0;

[0075] K, according to the integration step t s Calculate the integrated area and display the dissolved oxygen decay curve in the interactive display module;

[0076] L. The control module determines whether the dissolved oxygen value DO in each reaction bottle reaches the set value DO2 through the dissolved oxygen electrode detection, and stops the integral calculation after reaching DO2;

[0077] M. Arrange the results in each reaction bottle according to the κ value, and display the sorting results through an interactive display module;

[0078] N. Store the integrated area, κ value and dissolved oxygen decay curve corresponding to each reaction bottle.

[0079] Example 1

[0080] This embodiment provides a method for quickly evaluating the performance of an external carbon source in a sewage treatment plant. Specifically, it is a method for evaluating the effectiveness of the same carbon source at different concentrations, comprising the following steps:

[0081] A. Set the integration step size to t through the interactive display module s =5s, sludge activity constant 10000, set value Y1 = 30%, Y2 = 80%, set target dissolved oxygen value DO0 = 95%, set temperature value T0 = 35℃, aeration step length t1 = 10s, temperature control step length t2 = 10s, set dissolved oxygen value DO1 = 80%, DO2 = 30%;

[0082] B. Start the equipment through the interactive display module, and the water bath heater and flow circulation pump start running respectively;

[0083] C. Take the muddy water mixture from the end of the aerobic pool of the sewage treatment plant to which the carbon source is to be added and add it into the pre-reaction bottle until it reaches 80% of the total volume of the pre-reaction bottle;

[0084] D. Place the pre-reaction bottle in a constant temperature water bath. The bottom of the pre-reaction bottle corresponds to the electromagnetic stirrer. Place a stirrer in the pre-reaction bottle.

[0085] E. The aeration pump is started, and the aeration step time is t1. The dissolved oxygen content in the pre-reaction bottle is controlled at the dissolved oxygen value DO0 through the dissolved oxygen electrode and the aeration pump; the water bath heater is started, and the temperature control step time is t2. The water bath temperature in the water bath reaction tank is controlled at the set temperature value T0 through the temperature measuring electrode and the water bath heater;

[0086] F. Stop aeration when the liquid in the pre-reaction bottle meets the following conditions at the same time: the temperature is 35±0.5℃, and the dissolved oxygen value reaches the set value of 95±2%;

[0087] G. Dispense the liquid in the pre-reaction bottle into each reaction bottle in equal amounts, and place a stirring bar in each reaction bottle. Start the electromagnetic stirrer and drive the stirring bar to stir the liquid in the reaction bottle;

[0088] H. Add a standard carbon source liquid into a reaction bottle as a standard reaction bottle, use 1000 mg / L sodium acetate solution as a reference sample, and add the same volume of the carbon source liquid to be tested into each of the other reaction bottles;

[0089] I. The control module determines whether the dissolved oxygen value DO in each reaction bottle reaches the set value DO1 through the dissolved oxygen electrode detection, records the time t0 when the dissolved oxygen electrode detection value reaches DO1, and records the dissolved oxygen value DO after t0;

[0090] J. According to the integration step length t s Calculate the integrated area and display the dissolved oxygen decay curve in the interactive display module. The dissolved oxygen decay curves of the reference sample and sample 1, sample 2, and sample 3 are as follows: Figures 7 to 10 As shown;

[0091] K. The control module determines whether the dissolved oxygen value DO in each reaction bottle reaches the set value DO2 through the dissolved oxygen electrode detection, and stops the integral calculation after reaching DO2;

[0092] L. Arrange the results in each reaction bottle according to the κ value, and display the sorting results through an interactive display module;

[0093] M. Store the integrated area, κ value and dissolved oxygen decay curve corresponding to each reaction bottle.

[0094] Table 1 Ranking of experimental sample sludge activity results

[0095] Samples (ranked by concentration) Reference sample Sample 3 Sample 1 Sample 2 Sludge activity index κ 133.3 121.2 101.0 60.6

[0096] From the comparison of κ values ​​in Table 1 above, it can be concluded that sodium acetate has the largest sludge activity index as the reference sample, carbon source sample 3 is relatively close to the reference sample, the carbon source performance of carbon source sample 1 is lower than that of the reference and sample 3, and the sludge activity index of carbon source sample 2 is the lowest.

[0097] Example 2

[0098] This embodiment provides a method for evaluating the effectiveness of different carbon sources with the same economic cost, comprising the following steps:

[0099] A. Set the integration step size to t through the interactive display module s =5s, sludge activity constant 10000, set value Y1 = 10%, Y2 = 80%, set target dissolved oxygen value DO0 = 95%, set temperature value T0 = 35℃, aeration step length t1 = 10s, temperature control step length t2 = 10s, set dissolved oxygen value DO1 = 80%, DO2 = 10%;

[0100] B. Start the equipment through the interactive display module, and the water bath heater and flow circulation pump start running respectively;

[0101] C. Take the muddy water mixture from the end of the aerobic pool of the sewage treatment plant to which the carbon source is to be added and add it into the pre-reaction bottle until it reaches 75% of the total volume of the pre-reaction bottle;

[0102] D. Place the pre-reaction bottle in a constant temperature water bath. The bottom of the pre-reaction bottle corresponds to the electromagnetic stirrer. Place a stirrer in the pre-reaction bottle.

[0103] E. The aeration pump is started, and the aeration step time is t1. The dissolved oxygen content in the pre-reaction bottle is controlled at the dissolved oxygen value DO0 through the dissolved oxygen electrode and the aeration pump; the water bath heater is started, and the temperature control step time is t2. The water bath temperature in the water bath reaction tank is controlled at the set temperature value T0 through the temperature measuring electrode and the water bath heater;

[0104] F. Stop aeration when the liquid in the pre-reaction bottle meets the following conditions at the same time: the temperature is 35±0.5℃, and the dissolved oxygen value reaches the set value of 95±2%;

[0105] G. Dispense the liquid in the pre-reaction bottle into each reaction bottle in equal amounts, and place a stirring bar in each reaction bottle. Start the electromagnetic stirrer and drive the stirring bar to stir the liquid in the reaction bottle;

[0106] H. Add a standard carbon source liquid into a reaction bottle as a standard reaction bottle, use 10 ml of 30% industrial by-product sodium acetate solution as a reference sample, and add the same volume of the carbon source liquid to be tested into other reaction bottles;

[0107] I. The control module determines whether the dissolved oxygen value DO in each reaction bottle reaches the set value DO1 through the dissolved oxygen electrode detection, records the time t0 when the dissolved oxygen electrode detection value reaches DO1, and records the dissolved oxygen value DO after t0;

[0108] J. According to the integration step length t s Calculate the integrated area and display the dissolved oxygen decay curve in the interactive display module;

[0109] K. The control module determines whether the dissolved oxygen value DO in each reaction bottle reaches the set value DO2 through the dissolved oxygen electrode detection, and stops the integral calculation after reaching DO2;

[0110] L. Arrange the results in each reaction bottle according to the κ value, and display the sorting results through an interactive display module;

[0111] M. Store the integrated area, κ value and dissolved oxygen decay curve corresponding to each reaction bottle.

[0112] Table 2 Ranking of experimental sample sludge activity results

[0113] Sample name Reference sample Sample 3 Sample 2 Sample 1 Sludge activity index κ 70.4 52.3 51.0 38.6

[0114] From the comparison of κ values ​​in Table 2 above, it can be concluded that industrial sodium acetate has the largest sludge activity index as the reference sample, carbon source sample 3 and carbon source sample 2 are relatively close, and carbon source sample 1 has the lowest carbon source sludge activity index. In addition, a secondary inflection point of the curve appears in each set of data graphs, indicating that the added carbon source has been exhausted during the measurement time, and the interference of the slow-release carbon source can be basically ruled out. It should be pointed out that if there is no secondary inflection point of the curve in the data graph, it means that the added carbon source has not been completely consumed. At this time, the dosage of the reference carbon source should be reduced and retested. Through the above experiments, it can be concluded that under the same cost input, the carbon source of the reference sample is more beneficial to saving operating costs.

[0115] Example 3

[0116] Compared with Example 2, in Example 3, only in step C, the sludge-water mixture effluent from the aerobic tank of the sewage treatment plant to which the carbon source is to be added is added to 85% of the total volume of the pre-reaction bottle. The experimental results are the same as those in Example 2, and the sludge activity index value of the industrial sodium acetate as the reference sample is the largest.

[0117] In the range of 75-85% of the total volume, the addition amount of the same aerobic tank sludge did not affect the experimental results.

[0118] The parts of the present invention that are not described in detail are prior art. It is obvious to those skilled in the art that the present invention is not limited to the details of the above-mentioned exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention; therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is limited by the appended claims rather than the above description. Therefore, it is intended to include all changes within the meaning and scope of the equivalent elements of the claims in the present invention, and any figure marks in the claims should not be regarded as limiting the claims involved.

Claims

1. A method for rapidly evaluating the effectiveness of an added carbon source in a sewage treatment plant, based on equipment including a constant temperature water bath system, a main reaction system and a detection and control system; wherein the constant temperature water bath system includes a constant temperature water bath, a water bath heater, a temperature measuring electrode, a flow circulation pump and an electromagnetic stirrer, the constant temperature water bath forms a container for water bath heating, the water bath heater, the temperature measuring electrode and the flow circulation pump are arranged in the constant temperature water bath, and a plurality of electromagnetic stirrers are arranged outside the constant temperature water bath; the main reaction system includes a pre-reaction bottle and a reaction bottle, there are a plurality of reaction bottles, the pre-reaction bottle and the reaction bottle are placed in the constant temperature water bath when working, and the position corresponds to the electromagnetic stirrer, in A stirrer is provided in the pre-reaction bottle and the reaction bottle respectively. The pre-reaction bottle is also provided with a gas distributor, which is connected to an external aeration pump through a pipeline. Dissolved oxygen electrodes are provided in the corresponding pre-reaction bottle and the reaction bottle respectively. The detection control system includes a control module and an interactive display module. The control module is connected to a water bath heater, a temperature measuring electrode, a flow circulation pump, an electromagnetic stirrer, a dissolved oxygen electrode and an interactive display module respectively. The control module controls the operation of each component and performs data processing. The interactive display module enables the operator to input control information of the equipment and display the detection results. The interactive display module includes an input device and a display, and is characterized in that: Select a standard carbon source, convert the subsequent test results into the equivalent value of the standard carbon source, and use the equivalent value to evaluate the effectiveness of the carbon source to be tested; The sludge activity index κ is used to characterize the changing trend of sludge activity. The numerical meaning of the sludge activity index κ is the product of the inverse of the integral of the dissolved oxygen saturation decay curve and time and the sludge activity constant, that is: in f(t) is the decay function of dissolved oxygen saturation over time, the sludge activity constant N0=1000-100000, ； The following steps are involved: A. Set the integration step size t through the interactive display module s , sludge activity constant N0, set values ​​Y1, Y2, set target dissolved oxygen value DO0, set temperature value T0, aeration step length t1, temperature control step length t2, set dissolved oxygen values ​​DO1, DO2; B. Start the equipment through the interactive display module, and the water bath heater and flow circulation pump start running respectively; C. Take the sludge from the aerobic pool and add it to the pre-reaction bottle until it reaches 75-85% of the total volume of the pre-reaction bottle; D. Place the pre-reaction bottle in a constant temperature water bath, the bottom position of the pre-reaction bottle corresponds to the electromagnetic stirrer, a stirrer is placed in the pre-reaction bottle, the electromagnetic stirrer is started and drives the stirrer to stir the sludge in the pre-reaction bottle; E. The aeration pump is started, and the aeration step time is t1. The dissolved oxygen content in the pre-reaction bottle is controlled at the dissolved oxygen value DO0 through the dissolved oxygen electrode and the aeration pump; the water bath heater is started, and the temperature control step time is t2. The water bath temperature in the water bath reaction tank is controlled at the set temperature value T0 through the temperature measuring electrode and the water bath heater; F. Stop aeration when the liquid in the pre-reaction bottle meets the following conditions at the same time: the temperature is T0±0.5℃, and the dissolved oxygen value reaches the set value DO0±2%; G. Dispense the liquid in the pre-reaction bottle into each reaction bottle in equal amounts, and place a stirring bar in each reaction bottle. Start the electromagnetic stirrer and drive the stirring bar to stir the liquid in the reaction bottle; H. Add a standard carbon source liquid into a reaction bottle as a standard reaction bottle, and add the same volume of the carbon source liquid to be tested into other reaction bottles; I. Turn on the water bath heater, the temperature control step time is t2, and the water bath temperature in the water bath reaction tank is controlled at the set temperature value T0 through the temperature measuring electrode and the water bath heater; J. The control module determines whether the dissolved oxygen value DO in each reaction bottle reaches the set value DO1 through the dissolved oxygen electrode detection, records the time t0 when the dissolved oxygen electrode detection value reaches DO1, and records the dissolved oxygen value DO after t0; K, according to the integration step t s Calculate the integrated area and display the dissolved oxygen decay curve in the interactive display module; L. The control module determines whether the dissolved oxygen value DO in each reaction bottle reaches the set value DO2 through the dissolved oxygen electrode detection, and stops the integral calculation after reaching DO2; M. Arrange the results in each reaction bottle according to the κ value, and display the sorting results through an interactive display module; N. Store the integrated area, κ value and dissolved oxygen decay curve corresponding to each reaction bottle.

Images