Sulfur autotrophic denitrification filter tank and method for blocking generation of hydrogen sulfide in filter tank

Abstract

The invention relates to the technical field of sewage treatment, in particular to a sulfur autotrophic denitrification filter tank and a method for blocking generation of hydrogen sulfide in the filter tank. A fan is mounted on a backwashing gas inlet pipeline, and the backwashing gas inlet pipeline is communicated with a gas distribution system; a backwashing air inlet pneumatic valve is mounted on the backwashing air inlet pipeline, the backwashing water pump is connected with the water outlet pipeline, a backwashing water inlet pneumatic valve is mounted on the water outlet pipeline, and the hydrogen sulfide monitor is arranged above the tank body. The hydrogen sulfide monitor, the backwashing water pump, the fan, the backwashing air inlet pneumatic valve and the backwashing water inlet pneumatic valve are all in communication connection with the central controller. The invention aims to provide a sulfur autotrophic denitrification filter tank and a method for blocking generation of hydrogen sulfide in the filter tank in order to solve at least one technical problem related in the background technology.

Description

Technical Field

[0001] The present application relates to the technical field of sewage treatment, and in particular to a sulfur autotrophic denitrification filter and a method for blocking the generation of hydrogen sulfide in the filter. Background Art

[0002] Sulfur autotrophic denitrification technology refers to the ability of certain inorganic chemotrophic and phototrophic sulfur-oxidizing bacteria to utilize inorganic carbon (such as CO3 2- , HCO 3- ) as the carbon source, with reduced sulfur (S 0 , S 2- 、S2O3 2- The biochemical reaction process in which nitrogen (such as nitrogen oxides) is used as an electron donor and nitrate or nitrite is used as an electron acceptor to reduce it to nitrogen gas.

[0003] Compared with the traditional heterotrophic denitrification process, the sulfur autotrophic denitrification technology has the following advantages: no need to add an external carbon source, saving operating costs; no need to replace the filler, only replenishment; no risk of COD penetration leading to excessive effluent; no CO2 produced during the denitrification process; low sludge volume; long backwashing cycle, reducing energy consumption. However, there are also some disadvantages, mainly: the filler is easy to compact and clog; the sulfate content of the effluent increases; the investment cost is high; the denitrification load is low; the filter tank is in low dissolved oxygen and low nitrate / nitrite conditions for a long time, which will produce hydrogen sulfide (H2S) gas.

[0004] Hydrogen sulfide is an important chemical raw material. Normally, it is a colorless, flammable acidic gas. It can form an explosive mixture when mixed with air. It can cause combustion and explosion when exposed to open flames and high heat. It is also an acute and highly toxic substance with a rotten egg smell. Low concentrations of hydrogen sulfide have effects on the eyes, respiratory system and central nervous system. Inhaling a small amount of high-concentration hydrogen sulfide can be fatal in a short period of time. It can be seen that hydrogen sulfide gas not only affects the sensory experience of sewage treatment plant personnel, but also endangers the health and safety of personnel. Therefore, it is very necessary to take measures to solve the problem of hydrogen sulfide gas. Summary of the invention

[0005] The purpose of the present application is to provide a sulfur autotrophic denitrification filter and a method for blocking the production of hydrogen sulfide in the filter in response to at least one technical problem involved in the background technology.

[0006] In order to achieve the above objectives, this application adopts the following technical solutions:

[0007] One aspect of the present application provides a sulfur autotrophic denitrification filter tank, comprising a central controller, a backwash water pump, a fan and a tank body, as well as a hydrogen sulfide monitor, a backwash air inlet pipeline, a water outlet pipeline and an air distribution system installed on the tank body, the fan is installed on the backwash air inlet pipeline, the backwash air inlet pipeline is connected to the air distribution system, a backwash air inlet pneumatic valve is installed on the backwash air inlet pipeline, the backwash water pump is connected to the water outlet pipeline, a backwash water inlet pneumatic valve is installed on the water outlet pipeline, the hydrogen sulfide monitor is arranged above the tank body, and the hydrogen sulfide monitor, the backwash water pump, the fan, the backwash air inlet pneumatic valve and the backwash water inlet pneumatic valve are all communicatively connected to the central controller.

[0008] Optionally, the outlet pipeline includes an outlet main pipe and a backwash pipeline, the backwash pipeline is located outside the tank body, the backwash water inlet pneumatic valve is installed on the backwash pipeline, the backwash water pump is connected to the backwash pipeline, a water outlet pneumatic valve is installed on the outlet main pipe, and the water outlet pneumatic valve is located upstream of the backwash pipeline. The sulfur autotrophic denitrification filter also includes an inlet pipeline, a filter inlet pneumatic valve is installed on the inlet pipeline, and the outlet pneumatic valve and the filter inlet pneumatic valve are both communicatively connected to the central controller.

[0009] The beneficial effect of this technical solution is that before performing the air washing procedure and the water washing procedure, the water outlet main pipe and the water inlet pipe can be closed respectively through the water outlet pneumatic valve and the filter tank water inlet pneumatic valve, so that the gas introduced into the tank body and the backwashing liquid will not flow out from the water outlet main pipe and the water inlet pipe, so that the air washing procedure and the water washing procedure can achieve better results.

[0010] Optionally, the sulfur autotrophic denitrification filter provided in the present application further includes a filter level meter, which is installed on the tank body, and is located close to the edge of the tank mouth of the tank body. The filter level meter is used to communicate with the central controller.

[0011] The beneficial effect of this technical solution is that when the value of the filter tank liquid level gauge is higher than the preset height value, it indicates that the filter tank filler is clogged and needs to be backwashed. Combining the water washing procedure and the air washing procedure can not only improve the problem of filter tank filler clogging, but also block the production of hydrogen sulfide in the filter tank and remove the hydrogen sulfide inside and outside the tank body.

[0012] Optionally, the sulfur autotrophic denitrification filter provided in the present application further includes an inlet nitrate nitrogen monitor and an outlet water online monitor both installed on the tank body, the inlet nitrate nitrogen monitor is located close to the edge of the tank mouth of the tank body, and the outlet water online monitor is located at the bottom of the tank body, and the inlet nitrate nitrogen monitor and the outlet water online monitor are both communicatively connected to the central controller.

[0013] The beneficial effect of this technical solution is that when the nitrogen expulsion cycle reaches the preset time, it indicates that the filter has been running for a long time and a lot of nitrogen and other gases are attached to the surface of the filler, and nitrogen expulsion is required. The central controller issues a command to first close the filter inlet pneumatic valve and the filter outlet pneumatic valve, and then execute the water washing procedure to release the nitrogen accumulated in the filter and restore the filter head of the filter. The specific steps are to open the backwash inlet pneumatic valve, start the backwash water pump, maintain a certain backwash water washing intensity for a period of time, then close the backwash inlet pneumatic valve and the backwash water pump, and finally open the filter inlet pneumatic valve and the filter outlet pneumatic valve to resume the normal operation process.

[0014] Another aspect of the present application provides a method for blocking the generation of hydrogen sulfide in a filter tank, which is implemented by applying the sulfur autotrophic denitrification filter tank, and the method comprises:

[0015] The central controller receives the hydrogen sulfide gas concentration value above the pool body collected in real time by the hydrogen sulfide monitor;

[0016] The central controller determines whether the hydrogen sulfide gas concentration value is greater than a preset hydrogen sulfide gas concentration threshold. If so, the central controller controls the backwash air intake pneumatic valve and the fan to open. After continuously flushing with an airflow of a first intensity for a first period of time, the central controller controls the backwash air intake pneumatic valve and the fan to close.

[0017] Optionally, in the method for blocking the generation of hydrogen sulfide in the filter tank provided by the present application, the outlet pipeline includes an outlet main pipe and a backwash pipeline, the backwash pipeline is located outside the tank body, the backwash water inlet pneumatic valve is installed on the backwash pipeline, a water outlet pneumatic valve is installed on the outlet main pipe, the water outlet pneumatic valve is located upstream of the backwash pipeline, the sulfur autotrophic denitrification filter tank also includes an inlet pipeline, a filter tank water inlet pneumatic valve is installed on the inlet pipeline, and the outlet water pneumatic valve and the filter tank water inlet pneumatic valve are both communicatively connected to the central controller;

[0018] Accordingly, before the central controller controls the backwash air inlet pneumatic valve and the fan to open, the method further includes:

[0019] The central controller controls the filter tank water inlet pneumatic valve and the water outlet pneumatic valve to close;

[0020] Furthermore, after the central controller controls the backwash air inlet pneumatic valve and the fan to be closed, the method further includes:

[0021] The central controller controls the filter tank water inlet pneumatic valve and the water outlet pneumatic valve to open.

[0022] Optionally, in the method for blocking the generation of hydrogen sulfide in the filter provided by the present application, the sulfur autotrophic denitrification filter further comprises a filter level meter, the filter level meter is installed on the tank body, the position of the filter level meter is close to the edge of the tank mouth of the tank body, and the filter level meter is used to communicate with the central controller;

[0023] Accordingly, the method further includes:

[0024] The central controller receives the liquid level height value in the filter tank collected in real time by the filter tank level gauge. If the liquid level height value is greater than a preset liquid level height threshold, the central controller controls the filter tank water inlet pneumatic valve and the water outlet pneumatic valve to be closed, then opens the backwash air inlet pneumatic valve and the fan, and continuously flushes with the first intensity of airflow for the first time period. Then, the backwash water inlet pneumatic valve and the backwash water pump are opened, and the backwash water inlet pneumatic valve and the backwash water pump are continuously flushed with the second intensity of backwash water for the second time period. Then, the backwash air inlet pneumatic valve and the fan are closed, and the backwash water inlet pneumatic valve and the backwash water pump continue to remain in the open state and continue for the first time period. Then, the filter tank water inlet pneumatic valve and the water outlet pneumatic valve are opened.

[0025] Optionally, in the method for blocking the generation of hydrogen sulfide in the filter provided by the present application, the sulfur autotrophic denitrification filter also includes an inlet nitrate nitrogen monitor and an outlet water online monitor both installed in the tank body, the inlet nitrate nitrogen monitor is located near the edge of the tank mouth of the tank body, the outlet water online monitor is located at the bottom of the tank body, and the inlet nitrate nitrogen monitor and the outlet water online monitor are both communicatively connected to the central controller;

[0026] Accordingly, the method further includes:

[0027] When the nitrogen removal cycle reaches the third time, the central controller controls the filter tank water inlet pneumatic valve and the filter tank water outlet pneumatic valve to close, then opens the backwash water inlet pneumatic valve and the backwash water pump, and continues to flush for the first time with backwash water of the second intensity, then closes the backwash water inlet pneumatic valve and the backwash water pump, and finally opens the filter tank water inlet pneumatic valve and the filter tank water outlet pneumatic valve.

[0028] Optionally, in the method for blocking the production of hydrogen sulfide in the filter tank provided in the present application, the first intensity is greater than the second intensity, and the first duration is less than or equal to the second duration.

[0029] Optionally, in the method for blocking the production of hydrogen sulfide in the filter tank provided in the present application, the preset hydrogen sulfide gas concentration threshold is 10 ppm.

[0030] The technical solution provided by this application can achieve the following beneficial effects:

[0031] The sulfur autotrophic denitrification filter and the method for blocking the production of hydrogen sulfide in the filter provided by the present application, when the value of the hydrogen sulfide monitor is higher than the preset value, it indicates that a disproportionation reaction occurs in the filter to produce hydrogen sulfide gas and the concentration has accumulated to a threshold value that affects human health, the central controller issues an instruction to execute the air washing procedure to increase the dissolved oxygen concentration of the lower filler and block the production of hydrogen sulfide gas. Specifically, the backwash air inlet pneumatic valve is opened, and the fan is started. After flushing with an airflow of a certain intensity for a period of time, the backwash air inlet pneumatic valve and the fan are closed to resume normal operation. On the one hand, the dissolved oxygen content in the water body is increased to block the production of hydrogen sulfide, and on the other hand, the hydrogen sulfide accumulated above the tank body is cleared to reduce the risk of hydrogen sulfide poisoning for workers; a water washing procedure can also be performed during the air washing procedure, that is, the backwash water inlet pneumatic valve is opened during the air washing procedure, and the backwash water pump is started, and the flushing time is maintained for a period of time at a certain backwash water washing intensity, which can accelerate the rate of oxygen dissolution in the water body and accelerate the discharge of hydrogen sulfide gas in the water body.

[0032] The additional technical features and advantages of the present application will be more clearly explained in the following description, or can be understood through the specific practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions of the specific implementation methods of the present application, the following is a brief introduction to the drawings required for the description of the specific implementation methods. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0034] Figure 1 This is a schematic structural diagram of an implementation method of a sulfur autotrophic denitrification filter provided in an example of the present application.

[0035] Figure 2 A first flow chart of a method for blocking the production of hydrogen sulfide in a filter tank provided in an embodiment of the present application.

[0036] Figure 3 A second flow chart of the method for blocking the production of hydrogen sulfide in a filter tank provided in an embodiment of the present application.

[0037] Figure 4 Schematic diagram of the control input and output of the central controller provided for the application example of this application.

[0038] Figure 5 A control logic diagram of the central controller provided for the application example of this application.

[0039] Reference numerals:

[0040] 01-Influent nitrate nitrogen monitor; 02-Filter tank level gauge;

[0041] 03-Hydrogen sulfide monitor; 04-Backwash air intake pipeline;

[0042] 05-Backwash air inlet pneumatic valve; 06-Blower;

[0043] 07-Pool body; 08-Backwash pipeline;

[0044] 09-Backwash water inlet pneumatic valve; 10-Water outlet main pipe;

[0045] 11-Online water outlet monitoring instrument; 12-Gas distribution system;

[0046] 13-supporting layer; 14-lower packing layer;

[0047] 15-middle packing layer; 16-upper packing layer;

[0048] 17-water inlet pipeline; 18-filter tank water inlet pneumatic valve;

[0049] 19-water distribution channel; 20-water outlet pipeline;

[0050] 21-Water outlet pneumatic valve. DETAILED DESCRIPTION

[0051] The technical solution of the present application will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0052] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application 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 cannot be understood as limiting the present application. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0053] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0054] like Figure 1 As shown, one aspect of the present application provides a sulfur autotrophic denitrification filter tank, including a central controller, a backwash water pump, a fan 06 and a tank body 07, as well as a hydrogen sulfide monitor 03, a backwash air inlet pipeline 04, a water outlet pipeline 20 and an air distribution system 12 installed on the tank body 07, the fan 06 is installed on the backwash air inlet pipeline 04, the backwash air inlet pipeline 04 is connected to the air distribution system 12, a backwash air inlet pneumatic valve 05 is installed on the backwash air inlet pipeline 04, the backwash water pump is connected to the water outlet pipeline 20, and a backwash water inlet pneumatic valve 09 is installed on the water outlet pipeline 20, the hydrogen sulfide monitor 03 is arranged above the tank body 07, and the hydrogen sulfide monitor 03, the backwash water pump, the fan 06, the backwash air inlet pneumatic valve 05 and the backwash water inlet pneumatic valve 09 are all communicatively connected to the central controller.

[0055] The collection and treatment of hydrogen sulfide by the deodorization system will increase the construction cost. Usually, the deodorization system of the sewage treatment plant only collects and treats the exhaust gas from the grille, the grit chamber and the sludge treatment workshop, and does not include the denitrification filter unit. If the exhaust gas collection system is also added to the filter, it will not only increase the investment, but also hinder the operation and maintenance personnel from observing the operation of the denitrification filter, making it difficult to find and solve the problem in time. Therefore, the present invention proposes another method, that is, to study the generation pathway of hydrogen sulfide and block it.

[0056] Studies have shown that there are two main ways to produce hydrogen sulfide: one is desulfurization (desulfurization), which is the process in which sulfate-reducing bacteria (or desulfurizing bacteria) reduce sulfate to H2S under anaerobic and anoxic conditions. These microorganisms are mainly Desulfovibrio and Desulfobacterium; the other is formed by the decomposition of sulfur-containing organic matter under anaerobic conditions.

[0057] It can be seen that the production of hydrogen sulfide requires three conditions: rich organic matter (a large amount of sulfate in organic matter), anoxic environment and low pH value, among which hypoxia is the main reason for the production of hydrogen sulfide. In the sulfur autotrophic denitrification filter, the priority of the metabolism of sulfur and its compounds is: consumption of dissolved oxygen, denitrification (removal of nitrate / nitrite), disproportionation (production of sulfide), that is, in the top-in and bottom-out filter, the upper filler will first consume the dissolved oxygen carried in the influent, and then carry out the denitrification and denitrification process. When the lower filler is in low dissolved oxygen and low nitrate / nitrite conditions for a long time, H2S will be produced. Therefore, to solve the problem of hydrogen sulfide production, the method of increasing the intensity and duration of air-water backwashing can be adopted. On the one hand, the dissolved oxygen content in the water body can be increased, and on the other hand, the biomass can be reduced to appropriately increase the nitrate nitrogen concentration in the water body.

[0058] The sulfur autotrophic denitrification filter provided by the present application, when the value of the hydrogen sulfide monitor 03 is higher than the preset value, it indicates that a disproportionation reaction occurs in the filter to produce hydrogen sulfide gas and the concentration has accumulated to a threshold value that affects human health. The central controller issues an instruction to execute the air washing procedure to increase the dissolved oxygen concentration of the lower filler and block the generation of hydrogen sulfide gas. Specifically, the backwash air inlet pneumatic valve 05 is opened, and the fan 06 is started. After flushing with an airflow of a certain intensity for a period of time, the backwash air inlet pneumatic valve 05 and the fan 06 are closed to resume normal operation. On the one hand, this increases the dissolved oxygen content in the water body and blocks the generation of hydrogen sulfide. On the other hand, the hydrogen sulfide accumulated above the tank body 07 is removed to reduce the risk of hydrogen sulfide poisoning for the staff. The water washing procedure can also be performed during the air washing procedure, that is, the backwash water inlet pneumatic valve 09 is opened during the air washing procedure, and the backwash water pump is started. The flushing time is maintained for a period of time at a certain backwash water washing intensity, which can accelerate the rate of oxygen dissolution in the water body and accelerate the discharge of hydrogen sulfide gas from the water body.

[0059] Optionally, the outlet water pipeline 20 includes an outlet water main pipe 10 and a backwashing pipeline 08, the backwashing pipeline 08 is located outside the tank body 07, the backwashing water inlet pneumatic valve 09 is installed on the backwashing pipeline 08, and a water outlet pneumatic valve 21 is installed on the outlet water main pipe 10, and the water outlet pneumatic valve 21 is located upstream of the backwashing pipeline 08. The sulfur autotrophic denitrification filter also includes an inlet water pipeline 17, and a filter inlet pneumatic valve 18 is installed on the inlet water pipeline 17. The outlet water pneumatic valve 21 and the filter inlet pneumatic valve 18 are both communicatively connected to the central controller. In this way, before performing the air washing procedure and the water washing procedure, the water outlet main pipe 10 and the water inlet pipe 17 can be closed respectively through the water outlet pneumatic valve 21 and the filter tank water inlet pneumatic valve 18, so that the gas entering the tank body 07 and the backwashing liquid will not flow out from the water outlet main pipe 10 and the water inlet pipe 17, so that the air washing procedure and the water washing procedure can achieve better results.

[0060] Optionally, the sulfur autotrophic denitrification filter provided in the embodiment of the present application further includes a filter level meter 02, the filter level meter 02 is installed on the tank body 07, the position of the filter level meter 02 is close to the edge of the tank mouth of the tank body 07, and the filter level meter 02 is used to communicate with the central controller. In this way, when the value of the filter level meter 02 is higher than the preset height value, it indicates that the filter filler is blocked and backwashing is required. Combining the water washing procedure and the air washing procedure can not only improve the problem of blockage of the filter filler, but also block the generation of hydrogen sulfide in the filter, and remove the hydrogen sulfide inside and outside the tank body 07. Specifically, when the value of the filter level meter 02 is higher than the preset height value, the central controller will issue an instruction to first close the filter water inlet pneumatic valve 18 and the water outlet pneumatic valve 21, and then execute the air washing procedure. The specific steps are to open the backwashing air inlet pneumatic valve 05, and start the fan 06 to maintain the air washing intensity for a certain period of time. After that, the water washing procedure is synchronously executed to carry out air-water combined backwashing, the backwashing water inlet pneumatic valve 09 is opened, the backwashing water pump is started, and a certain backwashing water washing intensity is maintained for a period of time, and then the fan 06 and the backwashing air inlet pneumatic valve 05 are closed, and the water washing is continued for a period of time. Finally, the filter tank water inlet pneumatic valve 18 and the water outlet pneumatic valve 21 are opened to resume the normal operation process.

[0061] Optionally, the sulfur autotrophic denitrification filter provided in the embodiment of the present application further includes an inlet nitrate nitrogen monitor 01 and an outlet water online monitor 11 both installed in the tank body 07, the inlet nitrate nitrogen monitor 01 is located near the edge of the tank mouth of the tank body 07, the outlet water online monitor 11 is located at the bottom of the tank body 07, and the inlet nitrate nitrogen monitor 01 and the outlet water online monitor 11 are both connected to the central controller for communication. When the nitrogen removal cycle reaches the preset time, it indicates that the filter tank has been running for a long time, and a lot of nitrogen and other gases are attached to the surface of the filler, and nitrogen removal is required. The central controller sends out a command to first close the filter tank water inlet pneumatic valve 18 and the filter tank water outlet pneumatic valve 21, and then execute the water washing procedure to release the nitrogen accumulated in the filter tank and restore the filter head of the filter tank. The specific steps are to open the backwash water inlet pneumatic valve 09, start the backwash water pump, maintain a certain backwash water washing intensity for a period of time, then close the backwash water inlet pneumatic valve 09 and the backwash water pump, and finally open the filter tank water inlet pneumatic valve 18 and the filter tank water outlet pneumatic valve 21 to resume the normal operation process.

[0062] Preferably, the sulfur autotrophic denitrification filter provided in the embodiment of the present application further includes a supporting layer 13 , an upper filler layer 16 , a middle filler layer 15 , a lower filler layer 14 and a water distribution channel 19 .

[0063] Based on the above-mentioned sulfur autotrophic denitrification filter tank embodiment, the present application also provides an embodiment of a method for blocking the generation of hydrogen sulfide in the filter tank, see Figure 2 The method for blocking the generation of hydrogen sulfide in the filter tank specifically includes the following contents:

[0064] Step 100: The central controller receives the hydrogen sulfide gas concentration value above the pool body collected in real time by the hydrogen sulfide monitor.

[0065] It can be understood that the preset hydrogen sulfide gas concentration threshold is 10 ppm.

[0066] Step 200: The central controller determines whether the hydrogen sulfide gas concentration value is greater than a preset hydrogen sulfide gas concentration threshold value. If so, execute step 300; otherwise, return to step 100.

[0067] Step 300: The central controller controls the backwash air inlet pneumatic valve and the fan to open, and after continuously flushing with the airflow of the first intensity for a first period of time, the central controller controls the backwash air inlet pneumatic valve and the fan to close.

[0068] In order to further improve the reliability and effectiveness of the execution of the air washing procedure and the subsequent backwashing procedure, in one or more embodiments of the present application, the first intensity is greater than the second intensity, and the first duration is less than or equal to the second duration.

[0069] Specifically, the first strength may be 20 to 25 L / (m2.s), and the second strength may be 4 to 6 L / (m2.s). 2 .s).

[0070] Furthermore, the first duration may be 3 to 5 minutes, and the second duration may be 5 to 8 minutes.

[0071] From the above description, it can be seen that the sulfur autotrophic denitrification filter and the method for blocking the production of hydrogen sulfide in the filter provided by the embodiment of the present application, when the value of the hydrogen sulfide monitor is higher than the preset value, it indicates that a disproportionation reaction occurs in the filter to produce hydrogen sulfide gas and the concentration has accumulated to a threshold value that affects human health. The central controller issues an instruction to execute the air washing procedure to increase the dissolved oxygen concentration of the lower filler and block the production of hydrogen sulfide gas. Specifically, the backwash air inlet pneumatic valve is opened, and the fan is started. After flushing with an airflow of a certain intensity for a period of time, the backwash air inlet pneumatic valve and the fan are closed to resume normal operation. On the one hand, the dissolved oxygen content in the water body is increased and the production of hydrogen sulfide is blocked. On the other hand, the hydrogen sulfide accumulated above the tank body is removed to reduce the risk of hydrogen sulfide poisoning of the staff; the water washing procedure can also be performed during the air washing procedure, that is, the backwash water inlet pneumatic valve is opened during the air washing procedure, and the backwash water pump is started. The flushing time is maintained for a period of time at a certain backwash water washing intensity, which can accelerate the rate of oxygen dissolution in the water body and accelerate the discharge of hydrogen sulfide gas in the water body.

[0072] In order to further improve the effectiveness and reliability of blocking the production of hydrogen sulfide in the filter tank, in an embodiment of a method for blocking the production of hydrogen sulfide in the filter tank provided in the present application, the outlet pipeline includes an outlet main pipe and a backwash pipeline, the backwash pipeline is located outside the tank body, the backwash water inlet pneumatic valve is installed on the backwash pipeline, a water outlet pneumatic valve is installed on the outlet main pipe, the water outlet pneumatic valve is located upstream of the backwash pipeline, the sulfur autotrophic denitrification filter tank also includes an inlet pipeline, a filter tank water inlet pneumatic valve is installed on the inlet pipeline, the outlet water pneumatic valve and the filter tank water inlet pneumatic valve are both communicatively connected to the central controller, see Figure 3 The method for blocking the generation of hydrogen sulfide in the filter tank specifically includes the following contents:

[0073] There is also a step 210 between step 200 and step 300: the central controller controls the filter tank water inlet pneumatic valve and the water outlet pneumatic valve to close.

[0074] After step 300, step 310 is also included: the central controller controls the filter tank water inlet pneumatic valve and the water outlet pneumatic valve to open.

[0075] In order to further improve the effectiveness and reliability of blocking the generation of hydrogen sulfide in the filter, in an embodiment of a method for blocking the generation of hydrogen sulfide in the filter provided in the present application, the sulfur autotrophic denitrification filter also includes a filter level meter, which is installed on the tank body, and the position of the filter level meter is close to the edge of the tank mouth of the tank body. The filter level meter is used to communicate with the central controller, see Figure 3 The method for blocking the generation of hydrogen sulfide in the filter tank also specifically includes the following contents:

[0076] Step 400: The central controller receives the liquid level height in the filter tank collected in real time by the filter tank liquid level meter.

[0077] Step 500: The central controller determines whether the liquid level value is greater than a preset liquid level threshold value. If so, execute step 600; otherwise, return to step 400.

[0078] Step 600: The central controller controls the filter tank water inlet pneumatic valve and the water outlet pneumatic valve to close, opens the backwash air inlet pneumatic valve and the fan, and continuously flushes with the first intensity of airflow for the first time period, then opens the backwash water inlet pneumatic valve and the backwash water pump, and continuously flushes with backwash water of the second intensity for a second time period, closes the backwash air inlet pneumatic valve and the fan, and the backwash water inlet pneumatic valve and the backwash water pump continue to remain open for the first time period, and then opens the filter tank water inlet pneumatic valve and the water outlet pneumatic valve.

[0079] In order to further improve the effectiveness and reliability of blocking the production of hydrogen sulfide in the filter tank, in an embodiment of a method for blocking the production of hydrogen sulfide in the filter tank provided in the present application, the sulfur autotrophic denitrification filter tank also includes an inlet nitrate nitrogen monitor and an outlet water online monitor both installed in the tank body, the inlet nitrate nitrogen monitor is located near the edge of the tank mouth of the tank body, the outlet water online monitor is located at the bottom of the tank body, and the inlet nitrate nitrogen monitor and the outlet water online monitor are both communicatively connected to the central controller, see Figure 3 The method for blocking the generation of hydrogen sulfide in the filter tank also specifically includes the following contents:

[0080] Step 700: When the nitrogen removal cycle reaches the third time, the central controller controls the filter tank water inlet pneumatic valve and the filter tank water outlet pneumatic valve to close, opens the backwash water inlet pneumatic valve and the backwash water pump, and continuously flushes with backwash water of the second intensity for the first time period, then closes the backwash water inlet pneumatic valve and the backwash water pump, and finally opens the filter tank water inlet pneumatic valve and the filter tank water outlet pneumatic valve.

[0081] It is understandable that the third time may be 24 hours.

[0082] In order to further illustrate the above method for blocking the generation of hydrogen sulfide in the filter tank, the present application also provides an application example of the method for blocking the generation of hydrogen sulfide in the filter tank, see Figure 4 and Figure 5 , where A represents the liquid level value collected by the filter tank level meter, B represents the preset liquid level threshold, C represents the hydrogen sulfide gas concentration value above the tank body collected in real time by the hydrogen sulfide monitor, and D represents the nitrogen drive cycle.

[0083] Specifically, see Figure 4 , on the basis of the traditional backwash system, an online hydrogen sulfide monitor is added, and an automatic control system is designed to block the generation of hydrogen sulfide gas. The online monitors for inlet nitrate nitrogen and outlet nitrate nitrogen are used to monitor the nitrate nitrogen concentration of the filter inlet and outlet water, and transmit the data to the central controller; the filter level meter is used to monitor the filter liquid level and transmit the data to the central controller; the online hydrogen sulfide monitor is used to monitor the hydrogen sulfide gas concentration above the filter and transmit the data to the central controller. The main function of the central controller is to receive and process data such as the inlet and outlet nitrate nitrogen concentration, filter liquid level and hydrogen sulfide gas concentration.

[0084] See the backwash program setting of the central controller for details. Figure 5 When any of the following trigger conditions is met during the operation of the sulfur autotrophic denitrification filter, the backwash program is triggered. The set trigger conditions include: A is higher than B; C is higher than the set value of 15 mg / m3 (10 ppm); D reaches the set time of 24 hours.

[0085] When A is higher than B, it indicates that the filter packing is clogged and backwashing is required. The central controller will issue a command to first close the filter inlet and outlet pneumatic valves, and then execute the air washing procedure. The specific steps are to open the backwash air inlet valve and start the fan. The air washing intensity is 20~25L / (m 2 .s), the time is 3 to 5 minutes. Then the water washing procedure is carried out synchronously, and the air-water combined backwashing is carried out. The backwashing water inlet pneumatic valve is opened, and the backwashing water pump is started. The backwashing water washing intensity is 4 to 6L / (m 2 .s), the time is 5 to 8 minutes. Then close the fan and the backwash air inlet pneumatic valve, and continue to wash with water. The backwash water washing intensity is 4 to 6L / (m 2 .s), the time is 3 to 5 minutes. Finally, open the filter tank water inlet pneumatic valve and the filter tank water outlet pneumatic valve to resume normal operation.

[0086] When C is higher than the set value of 10ppm, it indicates that a disproportionate reaction has occurred in the filter tank to produce hydrogen sulfide gas and the concentration has accumulated to the threshold that affects human health. The central controller issues a command to execute the air washing program to increase the dissolved oxygen concentration of the lower layer of filler and block the generation of hydrogen sulfide gas. The specific steps are to open the backwash air inlet valve, start the fan, and the air washing intensity is 20~25L / (m 2 .s), the time is 3 to 5 minutes, after which the backwash air inlet pneumatic valve and fan are closed to resume normal operation.

[0087] When D reaches the set time of 24h, it indicates that the filter has been running for a long time, and a lot of nitrogen and other gases are attached to the surface of the packing, and nitrogen needs to be driven out. The central controller issues a command to first close the filter inlet and outlet pneumatic valves, and then execute the water washing procedure to release the nitrogen accumulated in the filter and restore the filter head. The specific steps are to open the backwash inlet pneumatic valve, start the backwash water pump, and the backwash water washing intensity is 4-6L / (m2.s) for 3-5min. Then close the backwash inlet pneumatic valve and backwash water pump, and finally open the filter inlet pneumatic valve and filter outlet pneumatic valve to resume normal operation.

[0088] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. Sulfur autotrophic denitrification filter, characterized in that: It includes a central controller, a backwash water pump, a fan and a pool body, as well as a hydrogen sulfide monitor, a backwash air inlet pipeline, a water outlet pipeline and an air distribution system installed on the pool body, the fan is installed on the backwash air inlet pipeline, the backwash air inlet pipeline is connected with the air distribution system, a backwash air inlet pneumatic valve is installed on the backwash air inlet pipeline, the backwash water pump is connected with the water outlet pipeline, a backwash water inlet pneumatic valve is installed on the water outlet pipeline, the hydrogen sulfide monitor is arranged above the pool body, the hydrogen sulfide monitor, the backwash water pump, the fan, the backwash air inlet pneumatic valve and the backwash water inlet pneumatic valve are all connected to the central controller for communication so as to block the generation of hydrogen sulfide gas when the presence of hydrogen sulfide gas in the sulfur autotrophic denitrification filter is detected.

2. The sulfur autotrophic denitrification filter according to claim 1, characterized in that: The outlet water pipeline includes an outlet water main pipe and a backwashing pipeline, the backwashing pipeline is located outside the tank body, the backwashing water inlet pneumatic valve is installed on the backwashing pipeline, the backwashing water pump is connected to the backwashing pipeline, a water outlet pneumatic valve is installed on the outlet water main pipe, and the water outlet pneumatic valve is located upstream of the backwashing pipeline. The sulfur autotrophic denitrification filter also includes an inlet water pipeline, a filter inlet pneumatic valve is installed on the inlet water pipeline, and the outlet water pneumatic valve and the filter inlet pneumatic valve are both communicatively connected to the central controller.

3. The sulfur autotrophic denitrification filter according to claim 2, characterized in that: It also includes a filter tank level meter, which is installed on the tank body. The position of the filter tank level meter is close to the edge of the tank mouth of the tank body. The filter tank level meter is used to communicate with the central controller.

4. The sulfur autotrophic denitrification filter according to claim 2, characterized in that: It also includes an inlet nitrate nitrogen monitor and an outlet water online monitor, both of which are installed on the pool body. The inlet nitrate nitrogen monitor is located close to the edge of the pool mouth of the pool body, and the outlet water online monitor is located at the bottom of the pool body. The inlet nitrate nitrogen monitor and the outlet water online monitor are both communicatively connected to the central controller.

5. A method for blocking the generation of hydrogen sulfide in a filter tank, characterized in that: The method is implemented by using the sulfur autotrophic denitrification filter as described in any one of claims 1 to 4, and the method comprises: The central controller receives the hydrogen sulfide gas concentration value above the pool body collected in real time by the hydrogen sulfide monitor; The central controller determines whether the hydrogen sulfide gas concentration value is greater than a preset hydrogen sulfide gas concentration threshold. If so, the central controller controls the backwash air intake pneumatic valve and the fan to open. After continuously flushing with an airflow of a first intensity for a first period of time, the central controller controls the backwash air intake pneumatic valve and the fan to close.

6. The method for blocking the generation of hydrogen sulfide in a filter tank according to claim 5, characterized in that: The outlet pipeline includes an outlet main pipe and a backwash pipeline, the backwash pipeline is located outside the tank body, the backwash water inlet pneumatic valve is installed on the backwash pipeline, the outlet main pipe is equipped with an outlet pneumatic valve, the outlet pneumatic valve is located upstream of the backwash pipeline, the sulfur autotrophic denitrification filter also includes an inlet pipeline, a filter water inlet pneumatic valve is installed on the inlet pipeline, and the outlet pneumatic valve and the filter water inlet pneumatic valve are both connected to the central controller for communication; Accordingly, before the central controller controls the backwash air inlet pneumatic valve and the fan to open, the method further includes: The central controller controls the filter tank water inlet pneumatic valve and the water outlet pneumatic valve to close; Furthermore, after the central controller controls the backwash air inlet pneumatic valve and the fan to be closed, the method further includes: The central controller controls the filter tank water inlet pneumatic valve and the water outlet pneumatic valve to open.

7. The method for blocking the generation of hydrogen sulfide in a filter tank according to claim 6, characterized in that: The sulfur autotrophic denitrification filter tank further comprises a filter tank level meter, which is installed on the tank body, and is located close to the edge of the tank mouth of the tank body, and is used for communication connection with the central controller; Accordingly, the method further includes: The central controller receives the liquid level height value in the filter tank collected in real time by the filter tank level gauge. If the liquid level height value is greater than a preset liquid level height threshold, the central controller controls the filter tank water inlet pneumatic valve and the water outlet pneumatic valve to be closed, then opens the backwash air inlet pneumatic valve and the fan, and continuously flushes with the first intensity of airflow for the first time period. Then, the backwash water inlet pneumatic valve and the backwash water pump are opened, and the backwash water inlet pneumatic valve and the backwash water pump are continuously flushed with the second intensity of backwash water for the second time period. Then, the backwash air inlet pneumatic valve and the fan are closed, and the backwash water inlet pneumatic valve and the backwash water pump continue to remain in the open state and continue for the first time period. Then, the filter tank water inlet pneumatic valve and the water outlet pneumatic valve are opened.

8. The method for blocking the generation of hydrogen sulfide in a filter tank according to claim 6, characterized in that: The sulfur autotrophic denitrification filter tank also includes an inlet nitrate nitrogen monitor and an outlet water online monitor, both of which are installed on the tank body. The inlet nitrate nitrogen monitor is located near the edge of the tank mouth of the tank body, and the outlet water online monitor is located at the bottom of the tank body. The inlet nitrate nitrogen monitor and the outlet water online monitor are both communicatively connected to the central controller. Accordingly, the method further includes: When the nitrogen removal cycle reaches the third time, the central controller controls the filter tank water inlet pneumatic valve and the filter tank water outlet pneumatic valve to close, then opens the backwash water inlet pneumatic valve and the backwash water pump, and continues to flush for the first time with backwash water of the second intensity, then closes the backwash water inlet pneumatic valve and the backwash water pump, and finally opens the filter tank water inlet pneumatic valve and the filter tank water outlet pneumatic valve.

9. The method for blocking the generation of hydrogen sulfide in a filter tank according to claim 7, characterized in that: The first intensity is greater than the second intensity, and the first duration is less than or equal to the second duration.

10. The method for blocking the generation of hydrogen sulfide in a filter tank according to claim 5, characterized in that: The preset hydrogen sulfide gas concentration threshold is 10 ppm.

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