A biological denitrification efficiency monitoring system

Abstract

The utility model relates to sewage treatment technical field, concretely relates to a biological denitrification efficiency monitoring system, is arranged based on sewage treatment biological denitrification system, including the first flow measuring instrument of setting on sewage raw water inlet channel, the second flow measuring instrument of setting on outer reflux channel, the third flow measuring instrument of setting on inner reflux channel, the fourth flow measuring instrument of setting at the water outlet of anoxic tank, and the second nitrate nitrogen monitor of setting at the end of anoxic tank, and the third nitrate nitrogen monitor of setting at the end of aerobic tank. The utility model is based on the original anoxic, aerobic end nitrate nitrogen monitor of sewage treatment system, and the flow measuring instrument on water inlet, inner and outer reflux, only through the mode of setting flow measuring instrument at the end of anoxic tank, can realize the monitoring of anoxic tank denitrification efficiency, and can be applicable to a variety of sewage treatment process systems, have universality, have important practical and guiding significance.

Description

Technical Field

[0001] This utility model relates to the field of wastewater treatment technology, specifically to a biological denitrification efficiency monitoring system. Background Technology

[0002] Currently, urban domestic sewage is generally treated at municipal sewage treatment plants to achieve water purification and recycling. The most widely used method is biological treatment, which removes COD, nitrogen, and phosphorus from sewage through the activity of microorganisms, such as A... 2 The O process treats wastewater by creating anaerobic, anoxic, and aerobic environments, combined with internal and external reflux.

[0003] Nitrogen removal in biological treatment relies on denitrification under anoxic conditions in an anoxic tank. The denitrification efficiency of the denitrification tank directly affects the overall denitrification efficiency of the wastewater treatment system, and consequently, the effluent quality. Therefore, monitoring the biological denitrification efficiency in the anoxic tank is essential.

[0004] In principle, by directly monitoring the nitrate nitrogen concentration at the front and back ends of the anoxic tank, and in conjunction with flow rate monitoring at the front and back ends of the anoxic tank, the nitrate nitrogen content at the front and back ends of the anoxic tank can be directly obtained, and the denitrification efficiency can then be calculated. However, in actual production, the cost of equipment is one of the key factors that cannot be ignored. It is particularly necessary to find a way to detect the denitrification efficiency of the biological system with a smaller modification cost.

[0005] In reality, wastewater treatment systems already have many monitoring instruments, such as instruments for detecting influent and internal / external backflow, and nitrate nitrogen concentration monitors for anoxic and aerobic terminals, which are essential for the stable operation of the wastewater treatment system. Therefore, integrating existing necessary resources to modify the biological treatment system at the lowest cost to achieve monitoring of biological nitrogen removal efficiency has important practical and guiding significance. Utility Model Content

[0006] The purpose of this invention is to address the shortcomings of the existing technology by providing a biological denitrification efficiency monitoring system, thereby achieving a universal biological denitrification efficiency monitoring system that is applicable to practical engineering use or modification.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: a biological denitrification efficiency monitoring system, which is arranged based on a wastewater treatment biological denitrification system, wherein a first flow meter is installed on the wastewater raw water inlet channel, a second flow meter is installed on the external return channel, a third flow meter is installed on the internal return channel, a fourth flow meter is installed at the outlet of the anoxic tank, a second nitrate nitrogen monitor is installed at the end of the anoxic tank, and a third nitrate nitrogen monitor is installed at the end of the aerobic tank.

[0008] Furthermore, a first nitrate nitrogen monitor is also installed on the raw wastewater inlet channel.

[0009] Furthermore, all flow meters are online flow meters, and all nitrate nitrogen monitors are online nitrate nitrogen monitors.

[0010] Furthermore, it also includes a field PLC, with each flow meter and each nitrate nitrogen monitor connected to the field PLC.

[0011] The beneficial effects of this utility model are: 1. This utility model can monitor the denitrification efficiency of the anoxic tank by simply setting a flow measuring instrument at the end of the anoxic tank, based on the existing nitrate nitrogen monitoring instruments at the end of the wastewater treatment system for anoxic and aerobic terminals, as well as the flow measuring instruments on the influent and internal and external recirculation. It is applicable to a variety of wastewater treatment process systems, has universality, and has important practical and guiding significance. 2. This utility model can monitor the denitrification efficiency of biological systems simply by adding a flow meter to the existing equipment. It has low usage or modification costs and is more convenient for promotion and application. 3. The monitoring system of this utility model has universality. By monitoring the changes in nitrate nitrogen content before and after the anoxic tank, the denitrification efficiency of the anoxic tank can be directly determined. The denitrification efficiency of the anoxic tank can reflect the overall denitrification efficiency of the biological system. It can basically meet the current operating process and has universality. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the installation arrangement in embodiments 1-2 of this utility model system; Figure 2 This is a schematic diagram of the installation arrangement in embodiments 3-5 of this utility model system.

[0013] The names corresponding to each mark in the diagram: 1. First nitrate nitrogen monitor; 2. Second nitrate nitrogen monitor; 3. Third nitrate nitrogen monitor; 4. First flow indicator and transmitter; 5. Second flow indicator and transmitter; 6. Third flow indicator and transmitter; 7. Fourth flow indicator and transmitter. Detailed Implementation

[0014] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model are within the protection scope of the present utility model.

[0015] Embodiments of this utility model: Example 1 like Figure 1 As shown, in this embodiment, based on inverted A 2 This utility model relates to a biological denitrification efficiency monitoring system for O process layout.

[0016] In this embodiment, a first nitrate nitrogen monitor 1 is installed on the main inlet channel, a second nitrate nitrogen monitor 2 is installed at the end of the anoxic tank, and a third nitrate nitrogen monitor 3 is installed at the end of the aerobic tank. The first nitrate nitrogen monitor 1 is used to monitor the concentration of nitrate nitrogen in the inlet water of the plant area; the second nitrate nitrogen monitor 2 is used to monitor the concentration of nitrate nitrogen at the end of the anoxic tank, and the third nitrate nitrogen monitor 3 is used to monitor the concentration of nitrate nitrogen at the end of the aerobic tank. Since the water content in the externally returned sludge can reach more than 98%, the monitoring data of the third nitrate nitrogen monitor 3 can also be used to express the concentration of nitrate nitrogen returned to the front end of the anoxic tank after conversion.

[0017] In this embodiment, a first flow indicator transmitter 4 is installed on the main inlet channel, a second flow indicator transmitter 5 is installed on the external return channel, a third flow indicator transmitter 6 is installed on the internal return channel, and a fourth flow indicator transmitter 7 is installed on the channel at the end of the anoxic tank and at the front end of the inlet. The first flow indicator transmitter 4 is used to measure the flow rate of the inlet water in the plant area, the second flow indicator transmitter 5 is used to measure the flow rate of the external return, the third flow indicator transmitter 6 is used to measure the flow rate of the internal return, and the fourth flow indicator transmitter 7 is used to monitor the effluent flow rate of the anoxic tank.

[0018] In this embodiment, the denitrification efficiency of the process is investigated based on the anoxic pond.

[0019] 1. The influent nitrate nitrogen concentration was measured using the first nitrate nitrogen monitor 1. (mg / L); 2. The influent flow rate is obtained sequentially through the first flow indicator transmitter 4, the second flow indicator transmitter 5, the third flow indicator transmitter 6, and the fourth flow indicator transmitter 7. (m) 3 / h), external return flow rate (m) 3 / h), internal recirculation flow rate (m) 3 / h) and the effluent flow rate at the end of the anoxic tank. (m) 3 / h); the second nitrate nitrogen monitor 2 measured the nitrate nitrogen concentration at the end of the anoxic pool. The nitrate nitrogen concentration at the end of the aerobic tank was measured by the third nitrate nitrogen monitor (mg / L). (mg / L).

[0020] The process considers multiple water intake points, meaning that part of the total water intake goes directly to the anaerobic zone.

[0021] Therefore, the nitrate nitrogen concentration at the front end of the anoxic tank (mg / L) is:

[0022] Therefore, the denitrification efficiency of the anoxic tank can be obtained. for:

[0023] Example 2 This embodiment is a further simplified version based on embodiment 1.

[0024] In wastewater treatment, the concentration of nitrate nitrogen in the influent to the plant is relatively low, generally 0.1~1 mg / L, and the sources of municipal domestic wastewater are generally relatively stable, meaning that the concentration of nitrate nitrogen in the influent can be set as a constant. (mg / L) (which can be obtained by statistically analyzing daily test data in the laboratory and measuring the average value), or can be omitted directly; the reason for omitting it directly is that, on the one hand, the concentration of nitrate nitrogen in the influent is generally low, and on the other hand, the influent is diluted by internal and external reflux.

[0025] Therefore, in this embodiment, the first nitrate nitrogen monitor 1 on the water inlet channel can be omitted, thereby reducing the equipment cost of the present invention system.

[0026] When the influent nitrate nitrogen concentration is set to a constant, that is, the nitrate nitrogen concentration in Example 1... In the calculation formula Replace with That's fine; if the influent nitrate nitrogen concentration is set to 0 mg / L, then... Simply replace it with 0; then the nitrate nitrogen concentration at the front end of the anoxic tank can be recalculated, and the subsequent denitrification efficiency can be calculated according to the denitrification efficiency formula in Example 1.

[0027] Example 3 like Figure 2 As shown, in this embodiment, the nitrogen removal efficiency monitoring system of this invention is based on an anaerobic-anoxic-aerobic process layout, which differs from the traditional plug-flow A...2 In this embodiment, the anoxic tank adopts a fully mixed (closed circulation) process, meaning that only part of the water at the end of the anoxic tank goes to the aerobic tank, while part returns to the front of the anoxic tank.

[0028] The present invention is still applicable to the above-mentioned processing techniques.

[0029] In this embodiment, the installation positions of each nitrate nitrogen monitor and each flow indicator transmitter are the same as in Embodiment 1, and will not be repeated here.

[0030] Since the concentration of nitrate nitrogen remains essentially unchanged in the anaerobic tank, and the water content in the externally returned sludge can reach over 98%, the nitrate nitrogen concentration data at the aerobic end monitored by the third nitrate nitrogen monitor 3 can also be used to express the concentration of nitrate nitrogen returned to the front end of the anoxic tank through conversion.

[0031] In this embodiment, the denitrification efficiency of the process is still based on the anoxic pond.

[0032] 1. The influent nitrate nitrogen concentration was measured using the first nitrate nitrogen monitor 1. (mg / L); 2. The influent flow rate is obtained sequentially through the first flow indicator transmitter 4, the second flow indicator transmitter 5, the third flow indicator transmitter 6, and the fourth flow indicator transmitter 7. (m) 3 / h), external return flow rate (m) 3 / h), internal recirculation flow rate (m) 3 / h) and the effluent flow rate at the end of the anoxic tank. (m) 3 / h); the second nitrate nitrogen monitor 2 measured the nitrate nitrogen concentration at the end of the anoxic pool. The nitrate nitrogen concentration at the end of the aerobic tank was measured by the third nitrate nitrogen monitor (mg / L). (mg / L).

[0033] Therefore, the nitrate nitrogen concentration at the front end of the anoxic tank (mg / L) is:

[0034] Therefore, the denitrification efficiency of the anoxic tank can be obtained. for:

[0035] Example 4 This embodiment is a further simplified version based on embodiment 3.

[0036] Similar to Example 2, the concentration of nitrate nitrogen in the influent can be set to a constant. (mg / L), or simply omitted; in this embodiment, the first nitrate nitrogen monitor 1 on the inlet channel can be omitted, thereby reducing the equipment cost of the system of this utility model.

[0037] When the influent nitrate nitrogen concentration is set to a constant, that is, the nitrate nitrogen concentration in Example 3... In the calculation formula Replace with That's fine; if the influent nitrate nitrogen concentration is set to 0 mg / L, then... Simply replace it with 0; then the nitrate nitrogen concentration at the front end of the anoxic tank can be recalculated, and the subsequent denitrification efficiency can be calculated according to the denitrification efficiency formula in Example 3.

[0038] Example 5 like Figure 2 As shown, in this embodiment, although the anaerobic-anoxic-aerobic process is still used, the anoxic tank adopts the traditional plug flow type, that is, the traditional A type is used in this embodiment. 2 O process.

[0039] In this embodiment, the installation positions of each nitrate nitrogen monitor and each flow indicator transmitter are the same as in Embodiment 1 or 3, and will not be described again.

[0040] Since the concentration of nitrate nitrogen remains essentially unchanged in the anaerobic tank, and the water content in the externally returned sludge can reach over 98%, the nitrate nitrogen concentration data at the aerobic end monitored by the third nitrate nitrogen monitor 3 can also be used to express the concentration of nitrate nitrogen returned to the front end of the anoxic tank through conversion.

[0041] In this embodiment, the denitrification efficiency of the process is still based on the anoxic pond.

[0042] 1. The influent nitrate nitrogen concentration was measured using the first nitrate nitrogen monitor 1. (mg / L); 2. The influent flow rate is obtained sequentially through the first flow indicator transmitter 4, the second flow indicator transmitter 5, the third flow indicator transmitter 6, and the fourth flow indicator transmitter 7. (m) 3 / h), external return flow rate (m) 3 / h), internal recirculation flow rate (m) 3 / h) and the effluent flow rate at the end of the anoxic tank. (m) 3 / h); the second nitrate nitrogen monitor 2 measured the nitrate nitrogen concentration at the end of the anoxic pool. (mg / L), the nitrate nitrogen concentration at the end of the anoxic tank was measured by the third nitrate nitrogen monitor. (mg / L).

[0043] For plug-flow anoxic tanks, there are .

[0044] Therefore, the nitrate nitrogen concentration at the front end of the anoxic tank (mg / L) is:

[0045] Therefore, the denitrification efficiency of the anoxic tank can be obtained. for:

[0046] It can be seen that the calculation formulas for the nitrate nitrogen concentration and denitrification efficiency at the front end of the anoxic tank in this embodiment are equivalent to a simplification of the corresponding calculation formulas in embodiment 3; it can also be seen that the system of this utility model is basically universal.

[0047] Meanwhile, in this embodiment, the concentration of nitrate nitrogen in the influent can be set to a fixed value or ignored, in accordance with the methods of Embodiments 2 and 4, thereby further reducing the cost of the equipment.

[0048] It should be noted that: In the above embodiments of this utility model, a nitrate nitrogen monitor is used. The nitrate nitrogen monitor is a mature existing device that is widely used in sewage treatment plants. Its structure, installation, and principle will not be described in detail. At the same time, a flow indicator and transmitter is also involved. In this utility model, a Doppler current meter can be used to measure the flow velocity of water in various channels. However, it should be noted that the Doppler current meter measures the flow velocity, and the product of the velocity and the cross-sectional area of ​​the water flow in the channel is the flow rate. The Doppler current meter is also widely used in sewage treatment plants. Its structure, installation, and principle will not be described in detail.

[0049] In addition, this utility model also relates to simple signal transmission. Both the nitrate nitrogen monitor and the Doppler current meter have signal transmission functions, transmitting the monitored data to the PLC on site. The data is then processed according to the calculation formula in the above embodiment, thereby realizing the monitoring of denitrification efficiency during biological denitrification.

Claims

1. A biological nitrogen removal efficiency monitoring system, configured based on a wastewater treatment biological nitrogen removal system, characterized in that: A first flow meter is installed on the raw wastewater inlet channel, a second flow meter is installed on the external return channel, a third flow meter is installed on the internal return channel, a fourth flow meter is installed at the outlet of the anoxic tank, a second nitrate nitrogen monitor is installed at the end of the anoxic tank, and a third nitrate nitrogen monitor is installed at the end of the aerobic tank.

2. The biological nitrogen removal efficiency monitoring system according to claim 1, characterized in that: The wastewater inlet channel is also equipped with a first nitrate nitrogen monitor.

3. A biological nitrogen removal efficiency monitoring system according to claim 1 or 2, characterized in that: All flow meters are online flow meters, and all nitrate nitrogen monitors are online nitrate nitrogen monitors.

4. The biological nitrogen removal efficiency monitoring system according to claim 3, characterized in that: It also includes a field PLC, and each flow meter and each nitrate nitrogen monitor are connected to the field PLC.

Images