A method of reducing harmful gas emissions from a sewage holding tank wastewater treatment process

Abstract

The present application provides a kind of method for reducing septic tank harmful gas emission in train toilet waste water treatment process, belong to sewage treatment technical field, including septic tank, septic tank is communicated with short path nitrification treatment device, short path nitrification treatment device is communicated with water storage tank, water storage tank backflow septic tank.The septic tank is used for the separation of granular organic matter in toilet waste water;Short path nitrification denitrification device is used to treat septic tank effluent and convert it into nitrification effluent;Water storage tank is used to store nitrification effluent and backflow to septic tank, utilize the high concentration nitrite nitrogen contained in nitrification effluent to realize the inhibition of harmful gas emission in septic tank.The treatment method of the present application realizes the emission reduction control of harmful gas in toilet waste water treatment process, reduces its threat to environment and residents, while improving the treatment efficiency of toilet waste water.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of sewage treatment, and particularly relates to a sewage treatment method for reducing harmful gas emission of a septic tank treatment unit in a high-speed train toilet bowl wastewater treatment facility. BACKGROUND

[0002] With the rapid increase of high-speed train operation mileage in China, the amount of high-speed train toilet bowl wastewater also increases significantly, and the treatment of toilet bowl wastewater is concerned. The train toilet bowl wastewater contains high concentrations of organic matter, nitrogen-containing substances and other pollutants, and the water quality indicators usually exceed the limit value of the urban sewer discharge standard. In most high-speed train depots, the toilet bowl wastewater treatment facility is usually composed of a septic tank and subsequent treatment facilities. The high-speed train toilet bowl wastewater is unloaded from the train into the septic tank for pretreatment after vacuum collection, and the effluent is discharged into the urban sewer after treatment by the subsequent treatment facilities.

[0003] In the septic tank, fecal particles, pathogenic microorganisms and other organic pollutants contained in the toilet bowl wastewater are partially removed through gravity settling, hydrolysis acidification, methanogenesis and sulfate reduction processes. However, due to the lack of effective electron acceptors in the septic tank, hydrogen sulfide, methane, ammonia and other harmful gases to human health and the environment are generated during the decomposition of organic matter by microorganisms. These gases not only exacerbate the greenhouse effect, but also affect the life and health of residents near the septic tank.

[0004] The toilet bowl wastewater pretreated by the septic tank contains high concentrations of ammonia nitrogen, which can be oxidized to nitrite nitrogen by short-cut nitrification treatment. The nitrified effluent is returned to the front-end septic tank to provide strong oxidizing electron acceptors, thereby improving the removal efficiency of organic matter and nitrogen-containing pollutants in the septic tank and reducing the emission of harmful gases from the septic tank. SUMMARY

[0005] The purpose of the present application is to provide a method for reducing harmful gas emission from a septic tank in a train toilet bowl wastewater treatment facility, i.e. using a short-cut nitrification treatment device as a subsequent treatment unit of septic tank effluent, and returning the nitrified effluent containing nitrite nitrogen to the septic tank to achieve the emission reduction goal of greenhouse gases and harmful gases in the train toilet bowl wastewater treatment process. To solve the technical problems existing in the background art.

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

[0007] The present application provides a method for reducing harmful gas emission from a septic tank in a train toilet bowl wastewater treatment process, comprising:

[0008] (1) Taking advantage of the characteristics of high-speed train operation during the day and concentrated discharge of toilet wastewater at night, the toilet wastewater treatment process is divided into four stages, including septic tank pretreatment stage, short-cut nitrification treatment stage, reflux denitrification stage and drainage stage.

[0009] (2) The septic tank pretreatment stage is from the night high-speed train parking to the next day high-speed train departure. After parking at night, the toilet wastewater is discharged into the septic tank for pretreatment, and the particulate matter in the wastewater is intercepted and settled as sludge, and the supernatant in the wastewater is stored in the septic tank for subsequent treatment;

[0010] (3) The short-cut nitrification stage is from the next day high-speed train departure to the completion of short-cut nitrification treatment of the supernatant in the septic tank. The short-cut nitrification treatment device is used as a subsequent treatment device for toilet wastewater pretreated by the septic tank, and the short-cut nitrification treatment device is in communication with the septic tank outlet. The influent flow and pH of the short-cut nitrification treatment device are controlled to convert all ammonia nitrogen in the septic tank effluent into nitrite nitrogen and achieve partial denitrification. The outlet of the short-cut nitrification treatment device is in communication with the water storage tank, and the treated nitrification effluent is discharged into the water storage tank for storage;

[0011] (4) The reflux denitrification stage is from the supernatant in the septic tank being discharged to the next day high-speed train parking. The outlet of the water storage tank is in communication with the septic tank, and during the operation of the high-speed train, the stored nitrification effluent is refluxed to the septic tank when no toilet wastewater is discharged into the septic tank. By taking advantage of the inhibitory effect of high-concentration nitrite nitrogen contained in the nitrification effluent on anaerobic digestion methanogenic microorganisms and sulfate-reducing microorganisms in the septic tank, the goal of reducing greenhouse gas and harmful gas emissions from the septic tank is achieved; at the same time, the particulate organic matter intercepted in the septic tank is used to complete the denitrification of nitrite in the nitrification effluent, achieving efficient removal of organic matter and high-concentration nitrogen and other pollutants in toilet wastewater.

[0012] (5) The drainage stage is from the next day high-speed train parking to the next day high-speed train departure. The treated toilet wastewater is discharged from the outlet of the septic tank.

[0013] Preferably, the specific steps include:

[0014] Step 1, from the night high-speed train parking to the next day train operation, the toilet wastewater is discharged into the septic tank for pretreatment, and the particulate organic matter is intercepted;

[0015] Step 2, after the next day high-speed train operation, the supernatant containing high-concentration ammonia nitrogen in the septic tank is discharged into the short-cut nitrification treatment device, and high-concentration nitrite nitrogen containing nitrification effluent is generated by short-cut nitrification treatment and discharged into the water storage tank for storage;

[0016] Step 3, during the next day's high-speed train operation, after the supernatant of the septic tank is completely discharged, the nitrified effluent is backflowed from the water storage tank to the septic tank to achieve the emission control of harmful gases in the septic tank, and at the same time, the removal of nitrogen and organic matter in the toilet wastewater is completed;

[0017] Step 4, before the train stops at night the next day, the toilet wastewater treated is discharged.

[0018] Preferably, the four-stage time of the toilet wastewater treatment process is determined according to the running and parking time of the high-speed train. Generally, 0:00-6:00 is the pretreatment stage of the septic tank, 6:00-16:00 is the short-cut nitrification stage, 16:00-23:00 is the backflow denitrification stage, and 23:00-24:00 is the drainage stage.

[0019] Preferably, the short-cut nitrification treatment device in step 2 is set to batch intermittent water feeding and is divided into anaerobic and aerobic stages to achieve the removal of organic matter and short-cut nitrification of ammonia nitrogen in the effluent of the septic tank. The specific process is water feeding and anoxic stirring-aerobic aeration-water feeding and anoxic stirring-aerobic aeration-anoxic stirring-effluent. By installing an intelligent monitoring and control system to adjust the time of each stage in real time, the treatment efficiency is improved and the treatment time is shortened;

[0020] Preferably, in order to ensure the stability of the short-cut nitrification treatment device, the short-cut nitrification treatment device in step 2 is equipped with pH monitoring equipment and alkalinity dosing equipment to stabilize the pH at 6.0-6.5, and DO monitoring equipment and adjustable rate air pump to control the DO at 0.5-0.8;

[0021] Preferably, after the short-cut nitrification treatment device in step 2, about 30% of the ammonia nitrogen and 90% of the organic matter in the effluent of the septic tank are removed, and at the same time, the remaining 70% of the ammonia nitrogen is completely converted into nitrite;

[0022] Preferably, the short-cut nitrification treatment device in step 2 does not need to be equipped with an additional sludge treatment process, and the reactor sludge can be discharged through steps 3 and 4, and the sludge is discharged into the septic tank through the water storage tank and is trapped as bottom mud;

[0023] Preferably, the inlet of the nitrified effluent into the septic tank in step 4 should be set at the bottom of the septic tank to increase the contact area of the nitrified effluent and the septic tank sludge and improve the inhibition effect of harmful gases. Drainage pipes or flow dividers and other facilities can be installed to enhance the inhibition effect;

[0024] Preferably, the harmful gas emission of the septic tank in step 4 is reduced by more than 80%;

[0025] Preferably, the removal effects of organic matter and total nitrogen in the toilet wastewater discharged in step 5 are more than 80% and 90%, respectively.

[0026] In the above technical solution, the related technical terms are explained as follows:

[0027] Train toilet wastewater: wastewater collected by the vacuum toilet of a high-speed train, mainly composed of urine, feces and a small amount of flushing water of passengers;

[0028] Short-cut nitrification treatment device: a biological treatment reactor for realizing wastewater denitrification, which can remove nitrogen, phosphorus, organic matter and other pollutants contained in wastewater;

[0029] Nitrification effluent: wastewater after the conversion of all ammonia nitrogen in septic tank effluent into nitrite nitrogen;

[0030] Nitrite nitrogen: an intermediate product of biological denitrification, which has certain biological toxicity and can inhibit the production of harmful gases such as methane and hydrogen sulfide by affecting the metabolism and community structure of methanogenic microorganisms and sulfate-reducing microorganisms in the septic tank.

[0031] Intelligent monitoring and control system: an intelligent management device for real-time monitoring and control of the short-cut nitrification system, which is composed of pH, COD, DO monitoring equipment, dosing equipment, instrument control system and central operation system and other components.

[0032] The present application has the following advantages:

[0033] The method for reducing harmful gas emission of septic tank in train toilet wastewater treatment process according to the present application realizes efficient control of harmful gas emission, helps to alleviate the greenhouse effect, and provides a low-cost and reliable solution for realizing green and sustainable development; also reduces the threat of harmful gas emission of septic tank in train toilet wastewater treatment process to the daily production and life of surrounding residents and their physical health; at the same time, the treatment method can also effectively improve the removal effect of water pollutants and reduce the treatment cost.

[0034] Additional aspects and advantages of the present application will be partially given in the following description, which will become apparent from the following description, or will be understood by those skilled in the art through practice of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0035] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0036] Figure 1 A flow chart of a method for reducing harmful gas emission of septic tank in train toilet wastewater treatment process according to the present application is shown in the figure, wherein 1 is a train toilet, 2 is a septic tank, 3 is a short-cut nitrification treatment device, and 4 is a water storage tank.

[0037] The present application will be further illustrated by the following examples in conjunction with the accompanying drawings. DETAILED DESCRIPTION

[0038] Embodiments of the present application will be described in detail below with reference to the drawings, in which like reference numerals refer to like elements throughout. The embodiments described below are examples of implementations of the present application and are not intended to limit the scope of the present application, as claimed.

[0039] As used herein, unless otherwise defined, all terms (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0040] It should also be understood that terms such as those defined in a generally dictionary dictionary are to be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and can not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0041] As used herein, unless otherwise defined, the singular forms "a", "an" and "the" include plural references unless the context clearly dictates otherwise.

[0042] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" and the like means that the particular feature, structure, material or characteristic being described is included in at least one embodiment or example of the present application. Moreover, the description of such a particular feature, structure, material or characteristic as being included in one embodiment or example is not intended to be taken as an exclusion of that feature, structure, material or characteristic from other embodiments or examples of the present application. That is, the particular features, structures, materials, or characteristics described are not exclusive to a single embodiment or example of the present application. Therefore, it is possible that a particular feature, structure, material or characteristic described as included in one embodiment or example of the present application can also be included in other embodiments or examples of the present application.

[0043] In the description of the present application, the terms "first", "second", and the like are used only to describe the features and do not imply or suggest relative importance or a specific number of the features indicated. Thus, the features defined with "first", "second" can include at least one of the features explicitly or implicitly. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise specifically defined.

[0044] In the description of the present specification, the orientation or positional relationship indicated by the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present technology and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present technology.

[0045] Unless otherwise expressly specified and limited, the terms "mount", "connect", "connect", "set" should be understood broadly, for example, it can be fixedly connected, set, or it can be detachably connected, set, or integrally connected, set. For those skilled in the art, the specific meaning of the above terms in the present technology can be understood according to the specific circumstances.

[0046] In order to facilitate the understanding of the present application, the present application will be further explained and described below with specific examples in conjunction with the drawings, and the specific examples do not constitute a limitation on the embodiments of the present application.

[0047] Those skilled in the art should understand that the drawings are only schematic diagrams of the embodiments, and the components in the drawings are not necessarily required for the implementation of the present application.

[0048] Embodiment 1

[0049] The purpose of this embodiment 1 is to provide a method for reducing the emission of harmful gases from septic tanks in train toilet wastewater treatment process, that is, using a short-term nitrification treatment device as a subsequent treatment unit for septic tank effluent, and then returning the nitrification effluent containing nitrite nitrogen to the septic tank, to achieve control of greenhouse gas and harmful gas emissions in train toilet wastewater treatment process. To solve the technical problems existing in the background art.

[0050] In order to achieve the above purpose, the present embodiment adopts a process for reducing the emission of harmful gases from septic tanks in train toilet wastewater treatment process, comprising:

[0051] (1) Taking advantage of the characteristics of high-speed train operation during the day and concentrated discharge of toilet wastewater at night, the toilet wastewater treatment process is divided into four stages, including septic tank pretreatment stage, short-term nitrification treatment stage, reflux denitrification stage and drainage stage.

[0052] (2) The septic tank pretreatment stage is from the night when the high-speed train stops to the next day when the high-speed train departs. After stopping at night, the toilet wastewater is concentrated and discharged into the septic tank for pretreatment, the particulate matter in the wastewater is trapped and settled as sludge, and the supernatant in the wastewater is stored in the septic tank for subsequent treatment;

[0053] (3) The short-cut nitrification stage is from after the high-speed train departs the next day to when the supernatant of the septic tank is completely treated by short-cut nitrification. The short-cut nitrification treatment device is used as a subsequent treatment device for the septic tank pretreated waste water of the toilet waste, and the short-cut nitrification treatment device is communicated with the outlet of the septic tank. The waste water flow and pH are controlled in the short-cut nitrification treatment device, so that the ammonia nitrogen in the outlet of the septic tank is completely converted into nitrite nitrogen and partial denitrification is achieved. The outlet of the short-cut nitrification treatment device is communicated with the water storage tank, and the treated nitrification effluent is discharged into the water storage tank for storage;

[0054] (4) The backflow denitrification stage is from when the supernatant of the septic tank is completely discharged to before the high-speed train stops the next day. The outlet of the water storage tank is communicated with the septic tank, and the stored nitrification effluent is backflowed to the septic tank when no toilet waste is discharged into the septic tank during the operation of the high-speed train. The inhibition effect of the high-concentration nitrite nitrogen contained in the nitrification effluent on the methanogenic microorganisms and sulfate-reducing microorganisms in the septic tank is utilized to achieve the goal of reducing the emission of greenhouse gases and harmful gases in the septic tank; at the same time, the denitrification of the nitrite nitrogen in the nitrification effluent is completed by the particulate organic matter intercepted in the septic tank, so that the organic matter and high-concentration nitrogen and other pollutants in the toilet waste are efficiently removed.

[0055] (5) The drainage stage is from before the high-speed train stops to when the treated toilet waste is discharged from the outlet of the septic tank.

[0056] Preferably, the specific steps include:

[0057] Step 1, from after the high-speed train stops at night to before the train runs the next day, the toilet waste is discharged into the septic tank for pretreatment, and the particulate organic matter is intercepted;

[0058] Step 2, after the high-speed train runs the next day, the supernatant of the septic tank containing high-concentration ammonia nitrogen is discharged into the short-cut nitrification treatment device, and high-concentration nitrite nitrogen-containing nitrification effluent is generated by short-cut nitrification treatment and is discharged into the water storage tank for storage;

[0059] Step 3, during the operation of the high-speed train the next day, after the supernatant of the septic tank is completely discharged, the nitrification effluent is backflowed to the septic tank from the water storage tank, so that the emission of harmful gases in the septic tank is controlled, and the removal of nitrogen and organic matter in the toilet waste is completed;

[0060] Step 4, before the train stops at night the next day, the treated toilet waste is discharged.

[0061] Preferably, the four stages of the toilet waste treatment process are determined according to the running and stopping time of the high-speed train. Roughly, 0:00-6:00 is the pretreatment stage of the septic tank, 6:00-16:00 is the short-cut nitrification stage, 16:00-23:00 is the backflow denitrification stage, and 23:00-24:00 is the drainage stage.

[0062] Preferably, to adapt to the processing load and ensure the processing effect, the short-range nitrification treatment device in step 2 is arranged to be fed water in batches intermittently and is divided into two stages of anaerobic and aerobic for improving the removal of organic matter in the septic tank effluent and the short-range nitrification effect of ammonia nitrogen, and the specific process is water feeding and anoxic stirring-aerobic aeration-water feeding and anoxic stirring-aerobic aeration-anoxic stirring-water discharge. The length of each stage is adjusted in real time by installing an intelligent monitoring and control system to improve the processing efficiency and shorten the processing time.

[0063] Preferably, to ensure the stability of the short-range nitrification device, the short-range nitrification treatment device in step 2 is arranged to stabilize the pH at 6.0-6.5 by installing a pH monitoring device and adding alkalinity, and the DO is controlled at 0.5-0.8 according to the DO monitoring device and the adjustable rate air pump;

[0064] Preferably, after the septic tank effluent is treated by the short-range nitrification in step 2, about 30% of total nitrogen and 90% of organic matter can be removed, and the remaining 70% of ammonia nitrogen is all converted into nitrite nitrogen;

[0065] Preferably, the short-range nitrification treatment device in step 2 does not need to be arranged with an additional sludge treatment process, and the reactor sludge can be discharged through steps 3 and 4, and the sludge is discharged into the septic tank and is intercepted as sludge;

[0066] Preferably, the inlet of the nitrification effluent discharged into the septic tank in step 4 should be arranged at the bottom of the septic tank for increasing the contact area of the nitrification effluent and the sludge in the septic tank and improving the inhibition effect of harmful gases, and a drainage pipe or a flow divider and other facilities can be added to enhance the inhibition effect;

[0067] Preferably, the harmful gas emission of the septic tank in step 4 is reduced by more than 80%;

[0068] Preferably, the removal effects of organic matter and total nitrogen are more than 80% and 90% respectively when the wastewater of the toilet bowl is discharged in step 5.

[0069] The method for reducing the harmful gas emission of the septic tank in the train toilet bowl wastewater treatment process described in the embodiment realizes efficient control of the harmful gas emission of the septic tank in the toilet bowl wastewater treatment process, helps to alleviate the greenhouse effect, provides a low-cost and reliable solution for realizing green and sustainable development, reduces the influence of harmful gas emission on the daily production and life of the surrounding residents and their health, and effectively improves the treatment effect of the toilet bowl wastewater treatment process and reduces the treatment cost.

[0070] Embodiment 2

[0071] In this embodiment 2, a method for reducing harmful gas emission of septic tank in train toilet wastewater treatment process is provided, that is, using a short-cut nitrification treatment device as a subsequent treatment unit of septic tank effluent, then returning the nitrification effluent containing nitrite nitrogen to the septic tank, and using the inhibitory effect of high concentration of nitrite nitrogen on the activity of methanogenic and sulfate-reducing microorganisms to control the greenhouse gas and harmful gas emission of septic tank in train toilet wastewater treatment process.

[0072] The specific process is as follows: train toilet wastewater is discharged into a septic tank for anaerobic digestion treatment, then the septic tank effluent is discharged into a short-cut nitrification treatment device, and the nitrification effluent is returned to the septic tank after treatment by the device.

[0073] The treatment effect of the method described in this embodiment on toilet wastewater is shown in Table 1.

[0074] Table 1 Water quality indicators and removal rates before and after toilet wastewater treatment

[0075] Item Wastewater concentration (mg / L) Effluent concentration (mg / L) Removal rate COD 3139±297 312±58 ≥90％ TN 1005±31 121±30 ≥88％

[0076] Embodiment 3

[0077] In this embodiment 3, a method for reducing harmful gas emission of septic tank in train toilet wastewater treatment process is provided, that is, using a short-cut nitrification treatment device as a subsequent treatment unit of septic tank effluent, then returning the nitrification effluent containing nitrite nitrogen to the septic tank, and using the inhibitory effect of high concentration of nitrite nitrogen on the activity of methanogenic and sulfate-reducing microorganisms to control the greenhouse gas and harmful gas emission of septic tank in train toilet wastewater treatment process.

[0078] The specific process is as follows: train toilet wastewater is discharged into a septic tank for anaerobic digestion treatment, then the septic tank effluent is discharged into a short-cut nitrification treatment device, and the nitrification effluent is returned to the septic tank after treatment by the device.

[0079] The harmful gas emission of septic tank before and after the implementation of the method described in this embodiment is shown in Table 2.

[0080] Table 2 Harmful gas indicators and removal rates of septic tank before and after the implementation of the method

[0081] Item Before improvement After improvement Removal rate Total gas amount 41 ± 3 liter / person / day 9 ± 1 liter / person / day ≥78％ [CAT] 22 ± 1 gram / person / day 4 ± 0.5 gram / person / day ≥80％ [H2S] 10 ± 2 mg / person / day 0.5 ± 0.1 mg / person / day ≥95％

[0082] The above describes the specific embodiments of the present application in combination with the drawings, but is not a limitation on the protection scope of the present application. Those skilled in the art should understand that various modifications or variations made by those skilled in the art on the basis of the disclosed technical solutions of the present application without creative labor should be covered within the protection scope of the present application.

Claims

1. A method for reducing harmful gas emissions from septic tanks in the wastewater treatment process of train toilets, utilizing the characteristic of high-speed trains operating during the day and centrally discharging wastewater from toilets at night, dividing the wastewater treatment process into four stages, including a septic tank pretreatment stage, a short-cut nitrification treatment stage, a recirculation denitrification stage, and a drainage stage, characterized in that... Comprise: (1) The septic tank pretreatment stage is from the night high-speed train parking to the next day high-speed train departure; After parking at night, the waste water in the toilet is concentrated and discharged into the septic tank for pretreatment, the particulate matter in the waste water is intercepted and settled as sludge, and the supernatant in the waste water is stored in the septic tank for subsequent treatment; (2) The short-cut nitrification stage is from the next day high-speed train departure to the completion of short-cut nitrification treatment of the supernatant in the septic tank; the short-cut nitrification treatment device is used as the subsequent treatment device of the waste water in the toilet after pretreatment in the septic tank, the short-cut nitrification treatment device is communicated with the outlet of the septic tank; the inflow and pH of the short-cut nitrification treatment device are controlled, so that all the ammonia nitrogen in the outlet water of the septic tank is converted into nitrite nitrogen and partial denitrification is realized; the outlet of the short-cut nitrification treatment device is communicated with the water storage tank, and the treated nitrification effluent is discharged into the water storage tank for storage; (3) The backflow denitrification stage is from the supernatant in the septic tank being discharged to the next day high-speed train parking; the outlet of the water storage tank is communicated with the septic tank, and during the operation of the high-speed train, When there is no waste water in the toilet discharged into the septic tank, the stored nitrification effluent is backflowed to the septic tank; By using the inhibition effect of high-concentration nitrite nitrogen contained in the nitrification effluent on the anaerobic digestion methanogenic microorganisms and sulfate-reducing microorganisms in the septic tank, the goal of reducing greenhouse gas and harmful gas emission of the septic tank is achieved; at the same time, by using the intercepted particulate organic matter in the septic tank, the denitrification of nitrite in the nitrification effluent is completed, and the organic matter and high-concentration nitrogen pollutants in the waste water in the toilet are efficiently removed; (4) The drainage stage is from the treated waste water in the toilet being discharged from the outlet of the septic tank before the high-speed train parking; The train toilet is communicated with the septic tank, the septic tank is communicated with the short-cut nitrification treatment device, the short-cut nitrification treatment device is communicated with the water storage tank, and the water storage tank is communicated with the septic tank; The short-cut nitrification treatment device treats the outlet water of the septic tank by biological treatment, so that all the ammonia nitrogen in the outlet water of the septic tank is converted into nitrite nitrogen and partial denitrification is realized; the septic tank is used for separating the particulate organic matter in the waste water in the toilet, and the water storage tank is used for storing the nitrification effluent; The four stages of the waste water treatment process in the toilet are determined according to the operation and parking time of the high-speed train, the septic tank pretreatment stage is from 0:00 to 6:00, the short-cut nitrification stage is from 6:00 to 16:00, the backflow denitrification stage is from 16:00 to 23:00, and the drainage stage is from 23:00 to 24:

00.

2. The method of claim 1, wherein, In step (2), the short-cut nitrification treatment device is set to batch intermittent water inflow and is divided into anaerobic and aerobic stages, which is used to improve the removal effect of organic matter and the short-cut nitrification effect of ammonia nitrogen in the outlet water of the septic tank; by installing an intelligent monitoring and control system to adjust the time of each stage in real time, the treatment efficiency is improved and the treatment time is shortened.

3. The method of claim 1, wherein, In order to ensure the stability of the short-cut nitrification device, in step (2), the short-cut nitrification treatment device is installed with a pH monitoring and dosing (alkalinity) system to stabilize the pH between 6.0 and 6.5, and a DO monitoring device and a speed-adjustable air pump are installed to control the DO of the reaction facility between 0.5 and 0.

8.

4. The method of claim 1, wherein, After the treatment of the short-range nitrification device in step (2), 30% of the total nitrogen and 90% of the organic matter in the effluent of the septic tank are removed, and the remaining 70% of the ammonia nitrogen is completely converted into nitrite nitrogen.

5. The method of claim 1, wherein, The short-range nitrification device in step (2) does not need to set up an additional sludge treatment process, and the reactor sludge can be discharged through steps (3) and (4), and the sludge is discharged into the septic tank through the water storage tank and is intercepted as the bottom mud.

6. The method of claim 1, wherein, The inlet of the nitrified effluent in step (3) should be set at the bottom of the septic tank to increase the contact area of the nitrified effluent and the sludge in the septic tank, improve the inhibition effect, and add a drainage pipe or a flow divider and other facilities to enhance the inhibition effect.

7. The method of claim 1, wherein, In step (3), the emission of harmful gases from the septic tank is reduced by more than 80%.

8. The method of claim 1, wherein, In step (4), the removal efficiency of organic matter and total nitrogen in the wastewater discharged from the toilet bowl is more than 80% and 90%, respectively.

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