WO2022160563A1 - Apparatus and method for deep removal of nitrogen from industrial wastewater by means of anaerobic ammonium oxidation - Google Patents

Abstract

Provided in the present invention are an apparatus and method for deep removal of nitrogen from industrial wastewater by means of anaerobic ammonium oxidation, relating to the technical field of sewage treatment. The apparatus provided in the present invention comprises a front inhibition area, an anaerobic ammonium oxidation system, an O₁AO₂ nitrogen removal area and a single sludge settling tank system, wherein the front inhibition area is provided with a first aeration system, an alkali addition system, an online pH measuring instrument and an online ammonia nitrogen measuring instrument; the anaerobic ammonium oxidation system is provided with a second aeration system and an immobilized filler layer; the O₁AO₂ nitrogen removal area comprises a first aeration area, an anoxic area and a second aeration area, which are sequentially connected in series and in communication with one another; and the single sludge settling tank system comprises a settling tank, a sludge outlet provided in the bottom of the settling tank, and a water outlet in the upper portion thereof. The apparatus provided in the present invention is a single sludge settling system, which can ensure the stability of the system while reducing the process complexity and operation costs. The apparatus provided in the present invention is used to perform deep removal of nitrogen from industrial wastewater by means of anaerobic ammonium oxidation, such that the total nitrogen removal rate is 97% or above.

Description

A device and method for deep denitrification of industrial wastewater by anaerobic ammonium oxidation

This application claims the priority of the Chinese patent application submitted to the China Patent Office on January 28, 2021, the application number is CN202110117407.2, and the invention name is "A device and method for deep denitrification by anaerobic ammonium oxidation of industrial wastewater", The entire contents of which are incorporated herein by reference.

technical field

The invention relates to the technical field of sewage treatment, in particular to a device and method for deep denitrification by anaerobic ammonia oxidation of industrial wastewater.

Background technique

The anaerobic ammonium oxidation process uses NO ₂ ^- -N (nitrite nitrogen) to oxidize NH ₄ ⁺ -N (ammonia nitrogen) to generate N ₂ and NO ₃ ^- -N (nitrite nitrogen), which is currently the most economical biological The denitrification process can save 62.5% of the energy consumption of aeration, and the removal of TN (total nitrogen) does not require an external carbon source, thereby reducing greenhouse gas emissions. It is a new energy-saving clean production technology for high ammonia nitrogen wastewater. However, the ANAMMOX denitrification process will theoretically generate some NO ₃ ^- -N, the theoretical denitrification efficiency is 88.7%, and the actual project is lower than 80%. Nitrogen unit to further remove TN (ammonia nitrogen, nitrite nitrogen and nitrate nitrogen). The existing treatment process is generally shown in Figure 1, and the deep denitrification unit 3 and the anammox unit 1 must be a dual-sludge system (settling tanks need to be set up respectively after the anammox and the deep denitrification unit, that is, sedimentation. Tank 2 and sedimentation tank 4), the sludge in the anammox system is short-range nitrification sludge and anammox bacteria. It is the traditional nitrification and denitrification sludge (the deep denitrification system is divided into nitrification zone 3.1 and denitrification zone 3.2, namely AO system). It is precisely because the anammox system needs to maintain short-range nitrification and anammox, the sludge is short-range nitrification and anammox bacteria; while the deep denitrification system is traditional nitrification and denitrification, and the sludge is traditional activated sludge. Therefore, the deep denitrification unit 3 and the anammox unit 1 must be a dual-sludge system, and the sludge and bacteria are trapped in their respective reaction systems.

The setting of the double sludge system requires two sets of sedimentation tanks, sludge return pumps, supporting pipelines and valves, and control systems, which increases the complexity of the process and increases investment and operating costs, reducing the technical advantages of the process in practical applications. .

SUMMARY OF THE INVENTION

In view of this, the purpose of the present invention is to provide a device and method for deep denitrification by anaerobic ammonium oxidation of industrial wastewater. The device provided by the present invention is a single sludge precipitation system, which can ensure the system while reducing process complexity and operating cost. stability.

In order to achieve the above-mentioned purpose of the invention, the present invention provides the following technical solutions:

The invention provides a device for deep denitrification by anaerobic ammonium oxidation of industrial wastewater, comprising:

A pre-suppression zone 1, the pre-suppression zone 1 includes a water inlet end 1.5 and a water outlet end 1.6, a first aeration system 1.1 is arranged at the inner bottom of the pre-suppression zone 1, and the pre-suppression zone 1 communicates with a The alkali adding system 1.2; the pre-inhibition zone 1 is also provided with an online pH measuring instrument 1.3 and an online ammonia nitrogen measuring instrument 1.4, and the online pH measuring instrument 1.3 is simultaneously connected with the alkali adding system 1.2 through a signal line;

The anaerobic ammonium oxidation system 2 connected to the water inlet end 2.3 and the water outlet end 1.6 of the pre-inhibition zone 1, the anaerobic ammonium oxidation system 2 is provided with a second aeration system 2.1 and immobilized fillers in order from bottom to top Layer 2.2, anammox bacteria are attached to the immobilized filler layer 2.2;

The water inlet end 3.8 is connected to the O ₁ AO ₂ denitrification zone 3 through 2.4 with the outlet end of the anammox system 2, and the O ₁ AO ₂ denitrification zone 3 includes a first aeration zone 3.1 connected in series in sequence , anoxic zone 3.2 and second aeration zone 3.3; the first aeration zone 3.1 is communicated with the water outlet 2.4 of the anammox system 2, and the inner bottom of the first aeration zone 3.1 and the second aeration zone 3.3 are respectively A third aeration system 3.4 and a fourth aeration system 3.6 are provided; the anoxic zone 3.2 is connected with a carbon source dosing system 3.7; the second aeration zone 3.3 is provided with a water outlet 3.3.1;

A single sludge sedimentation tank system 4 in which the water inlet 4.4 is communicated with the water outlet 3.3.1 of the second aeration zone 3.3, and the single sludge sedimentation tank system 4 includes a sedimentation tank 4.1 and a sludge set at the bottom of the sedimentation tank 4.1. The outlet 4.2 and the upper water outlet 4.3, the sludge outlet 4.2 is branched into a sludge return port 4.2.1 and a sludge discharge port 4.2.2, and the sludge return port communicates with the water inlet end of the pre-inhibition zone 1 .

Preferably, a stirrer 3.5 is also provided in the anoxic zone 3.2.

Preferably, the immobilized filler layer 2.2 is a polyurethane filler and/or a polypropylene filler; the filling amount of the immobilized filler layer 2.2 is 40-60% of the effective volume of the anammox system 2 .

Preferably, the second aeration zone 3.3 is further provided with a water outlet return port 3.3.2, and the water outlet return port 3.3.2 communicates with the water inlet end 1.5 of the pre-inhibition zone 1; the water outlet return port 3.3.2 is connected to A return pump 6 is provided on the connecting pipeline of the pre-inhibition zone 1, and the return pump 6 is connected with the online ammonia nitrogen measuring instrument 1.4 through a signal line.

Preferably, the water outlet end 1.6 of the pre-inhibition zone 1 is provided with a number of water distribution holes.

Preferably, the water outlet end 2.4 of the anammox system 2 is provided with several water distribution holes.

Preferably, the pipelines of the sludge return port 4.2.1 and the sludge discharge port 4.2.2 are also provided with a sludge return pump 7 and a sludge discharge pump 8 respectively; the sludge return pump 7 and the online ammonia nitrogen analyzer 1.4 Connect through the signal line.

The invention provides a method for deep denitrification by anaerobic ammonium oxidation of industrial wastewater, comprising the following steps:

(S1) The industrial wastewater to be treated enters the pre-suppression zone 1, and is mixed with the backflow sludge from the sedimentation tank 4.1 through the sludge return port 4.2.1 to the pre-suppression zone 1 under the action of the first aeration system 1.1, The pH value in the pre-suppression zone 1 is adjusted to 7.5-8.2 by adding alkaline substances to the alkali-adding system 1.2, and the flow rate of the reflux sludge is adjusted to adjust the ammonia nitrogen concentration in the pre-suppression zone 1 to 200-500 mg/L, so The pH value and ammonia nitrogen concentration are monitored in real time by the online pH measuring instrument 1.3 and the online ammonia nitrogen measuring instrument 1.4 respectively;

(S2) The wastewater treated by the pre-inhibition zone 1 enters the anaerobic ammonia oxidation system 2. Under the action of the second aeration system 2.1, the ammonia oxidizing bacteria convert the NH ₄ ⁺ -N in the wastewater into NO ₂ ^- - N, the anammox bacteria attached to the immobilized packing layer 2.2 react with NH ₄ ⁺ -N and NO ₂ ^- -N to generate nitrogen gas and NO ₃ ^- -N;

(S3) The wastewater treated by the anammox system 2 enters the O ₁ AO ₂ denitrification zone 3, and under the action of the third aeration system 3.4 in the aeration zone 3.1, the remaining water in the anammox system 2 is removed The NH ₄ ⁺ -N is nitrated to NO ₂ ^- -N;

The treated wastewater flowing out of the aeration zone 3.1 enters the anoxic zone 3.2, and the organic carbon source is added to the anoxic zone 3.2 through the carbon source dosing system 3.7 to denitrify NO ₂ ^- -N and NO ₃ ^- -N into nitrogen. ;

The treated wastewater flowing out of the anoxic zone 3.2 enters the second aeration zone 3.3, and the remaining organic carbon source in the anoxic zone 3.2 is removed under the action of the fourth aeration system 3.6;

(S4) The wastewater treated by the second aeration zone 3.3 enters the single sludge sedimentation tank system 4, and the sludge is separated in the sedimentation tank 4.1. The separated sludge is partially returned to the pre-suppression zone 1, and the rest is discharged from the sludge The outlet 4.2.2 is discharged, and the separated supernatant is discharged from the water outlet 4.3.

Preferably, the wastewater treated by the second aeration zone 3.3 is also partially returned to the pre-suppression zone 1 through the water outlet return port 3.3.2.

Preferably, in the step (1), the hydraulic retention time of the pre-inhibition zone 1 is 30-60 min; the temperature in the pre-inhibition zone 1 is 28-32°C.

Preferably, the dissolved oxygen in the anammox system 2 in the step (2) is less than or equal to 0.5 mg/L.

Preferably, in the step (3), the ammonia nitrogen concentration in the aeration zone 3.1 is less than or equal to 5 mg/L; the organic carbon source added in the anoxic zone 3.2 includes sodium acetate and/or methanol; the organic carbon The added amount of the source is 1.71 times the removal amount of NO ₂ ^- -N or 2.86 times the removal amount of NO ₃ ^- -N; the dissolved oxygen in the second aeration zone 3.3 is less than or equal to 2.0 mg/L.

Preferably, the reflux ratio of the sludge in the step (3) is 0.5-1.

The invention provides a device for deep denitrification by anaerobic ammonium oxidation of industrial wastewater, comprising a pre-inhibition zone 1, an anammox system 2, an O ₁ AO ₂ denitrification zone 3 and a single sludge sedimentation tank system 4; The pre-inhibition zone 1 is provided with a first aeration system 1.1, an alkali addition system 1.2, an online pH measuring instrument 1.3 and an online ammonia nitrogen measuring instrument 1.4; the anaerobic ammonia oxidation system 2 is provided with a second aeration system 2.1 and a fixed chemical filler layer 2.2; the O ₁ AO ₂ denitrification zone 3 includes a first aeration zone 3.1, anoxic zone 3.2 and a second aeration zone 3.3 that are connected in series; the single sludge sedimentation tank system 4 includes a sedimentation tank 4.1 , Set at the sludge outlet 4.2 at the bottom of the sedimentation tank 4.1 and the water outlet 4.3 at the upper part. The beneficial effects of the present invention are as follows:

The short-range nitrification of the single-sludge system is difficult to control (NH ₄ ⁺ -N is difficult to stably convert into NO ₂ ^- -N), so the traditional systems are all double-sludge systems; the present invention sets a front end in the front end of the anammox system In the inhibition zone, the microorganisms are inhibited and panned through the regulation of the pH value of the ammonia nitrogen in the influent, inhibiting the non-denitrifying bacteria, maintaining the proliferation of ammonia oxidizing bacteria, continuously purifying the bacteria, and realizing the stable short-range nitrification of the anammox system. It can effectively improve the stability of the system. The anammox system does not need to set up a sludge sedimentation system. Only one set of sedimentation system in the O ₁ AO ₂ denitrification zone can achieve the effect of deep denitrification. The device provided by the invention is a single-sludge sedimentation system. Compared with the traditional double-sludge system, it can save the sedimentation tank, the sludge return, sludge discharge, water distribution system matched with the sedimentation tank, as well as the matching water pump, pipeline, control system and instrument. and other equipment.

In addition, the traditional double sludge system, the deep denitrification relies on traditional nitrification and denitrification denitrification, generally an AO system, the nitrification process converts NH ₄ ⁺ -N into NO ₃ ^- -N, and the denitrification process converts NO ₃ ^- - N is reduced to nitrogen; the invention sets an O ₁ AO ₂ denitrification zone, which is a short-range nitrification and denitrification and denitrification process. The short-range nitrification process converts NH ₄ ⁺ -N into NO ₂ ^- -N, and the denitrification process converts NO ₂ ^- - N is reduced to nitrogen, which can save 25% of aeration energy consumption and 40% of carbon source compared with the traditional nitrification and denitrification process.

The invention also provides a method for deep denitrification by anaerobic ammonium oxidation of industrial waste water. The device provided by the invention is used to carry out deep denitrification and anaerobic ammonium oxidation of industrial waste water, and the removal rate of total nitrogen (TN) is above 97%. For most of the industrial sewage, the discharge standard can be met after being treated by the device.

Instruction drawings

Figure 1 is a schematic diagram of a traditional deep denitrification anammox device; in Figure 1, 1-anammox system, 2-settling tank, 3-deep denitrification unit, 3.1-nitrification zone, 3.2-denitrification zone, 4- sedimentation tank;

Fig. 2 is a schematic diagram of the deep denitrification anammox device provided by the present invention, in Fig. 2, 1-pre-suppression zone, 1.1-first aeration system, 1.2-alkali adding system, 1.3-on-line pH measuring instrument, 1.4- -On-line ammonia nitrogen analyzer, 1.5- inlet end of pre-suppression zone, 1.6- outlet end of pre-suppression zone; 2- anaerobic ammonia oxidation system, 2.1- second aeration system, 2.2- immobilized packing layer, 2.3-water inlet end, 2.4-water outlet end, 3-O ₁ AO ₂ denitrification zone, 3.1-aeration zone 1, 3.1.1-water outlet end, 3.2- anoxic zone, 3.2.1-water outlet end, 3.3- Aeration zone 2, 3.3.1-water outlet, 3.3.2-water return outlet, 3.4-third aeration system, 3.5-agitator, 3.6-fourth aeration system, 3.7-carbon source dosing system, 3.8 - Water inlet, 4-single sludge sedimentation tank system, 4.1- sedimentation tank, 4.2- sludge outlet, 4.2.1- sludge return outlet, 4.2.2- sludge discharge outlet, 4.3- water outlet, 4.4- Water inlet, 5-inlet pump, 6-return pump, 7-sludge return pump, 8-sludge pump.

Detailed ways

The invention provides a device for deep denitrification by anaerobic ammonium oxidation of industrial wastewater, comprising:

A pre-suppression zone 1, the pre-suppression zone 1 includes a water inlet end 1.5 and a water outlet end 1.6, a first aeration system 1.1 is arranged at the inner bottom of the pre-suppression zone 1, and the pre-suppression zone 1 communicates with a The alkali adding system 1.2; the pre-inhibition zone 1 is also provided with an online pH measuring instrument 1.3 and an online ammonia nitrogen measuring instrument 1.4, and the online pH measuring instrument 1.3 is simultaneously connected with the alkali adding system 1.2 through a signal line;

The anaerobic ammonium oxidation system 2 connected to the water inlet end 2.3 and the water outlet end 1.6 of the pre-inhibition zone 1, the anaerobic ammonium oxidation system 2 is provided with a second aeration system 2.1 and immobilized fillers in order from bottom to top Layer 2.2, anammox bacteria are attached to the immobilized filler layer 2.2;

The water inlet end 3.8 is an O ₁ AO ₂ denitrification zone 3 that communicates with the outlet end of the anammox system 2, and the O ₁ AO ₂ denitrification zone 3 includes a first aeration zone 3.1, an aeration zone 3.1, a lack of The oxygen zone 3.2 and the second aeration zone 3.3; the first aeration zone 3.1 is in communication with the water outlet 2.4 of the anammox system 2, and the inner bottom of the first aeration zone 3.1 and the second aeration zone 3.3 are respectively provided with The third aeration system 3.4 and the fourth aeration system 3.6; the anoxic zone 3.2 is connected with a carbon source dosing system 3.7; the second aeration zone 3.3 is provided with a water outlet 3.3.1;

A single sludge settling tank system 4 connected with the water inlet 4.4 and the water outlet 3.3.1 of the second aeration zone 3.3, the single sludge settling tank system 4 includes a settling tank 4.1, a sludge set at the bottom of the settling tank 4.1 The outlet 4.2 and the upper water outlet 4.3, the sludge outlet 4.2 is branched into a sludge return port 4.2.1 and a sludge discharge port 4.2.2, the sludge return port 4.2.1 and the inlet of the pre-inhibition zone 1 The water end 1.5 is connected.

The device for deep denitrification by anaerobic ammonium oxidation of industrial wastewater provided by the present invention is shown in FIG. 2 .

The device for deep denitrification by anaerobic ammonium oxidation of industrial wastewater provided by the present invention includes a pre-inhibition zone 1; the pre-inhibition zone 1 includes a water inlet end 1.5 and a water outlet end 1.6, and the pre-inhibition zone 1 is provided with a first Aeration system 1.1, alkali adding system 1.2, online pH measuring instrument 1.3 and online ammonia nitrogen measuring instrument 1.4. In the present invention, the water inlet end 1.5 of the pre-suppression zone 1 is preferably provided with an inlet water pump 5. The present invention has no special requirements for the inlet water pump 5, and an inlet water pump well known to those skilled in the art can be used. In the present invention, the first aeration system 1.1 is arranged at the bottom of the pre-inhibition zone 1. The present invention has no special requirements for the first aeration system 1.1. Can. In the present invention, the alkali addition system 1.2 is preferably arranged above the pre-inhibition zone 1, and the outlet of the alkali addition system 1.2 is connected to the pre-inhibition zone 1; the structure of the alkali addition system 1.2 in the present invention There is no special requirement, as long as the alkali can be added. In the present invention, the pre-inhibition zone 1 is also provided with an online pH measuring instrument 1.3 and an online ammonia nitrogen measuring instrument 1.4. The present invention has no special requirements for the online pH measuring instrument 1.3 and the online ammonia nitrogen measuring instrument 1.4. A pH measuring instrument and an ammonia nitrogen measuring instrument well-known to those skilled in the art are sufficient; the online pH measuring instrument 1.3 is connected with the alkali adding system 1.2 through a signal line at the same time, and the monitoring data of the online pH measuring instrument 1.3 is used to adjust the real-time adjustment of the alkali adding system 1.2. The amount of alkali is added, and the pH value is controlled within the set range; the online ammonia nitrogen measuring instrument 1.4 monitors the ammonia nitrogen concentration in the pre-inhibition zone 1 in real time.

In the present invention, the function of the pre-suppression zone 1 is to optimize the bacterial species of the suspended sludge returned from the sedimentation tank to the pre-suppression zone by controlling the pH value and ammonia nitrogen concentration in the pre-suppression zone, so as to inhibit non-denitrification. The activity of functional bacteria (NOB) promotes the growth of denitrifying bacteria (AOB).

The anammox deep denitrification device for industrial wastewater provided by the present invention includes an anammox system 2, and the water inlet end 2.3 of the anammox system 2 is communicated with the outlet end 1.6 of the pre-inhibition zone 1. In the present invention, the water outlet end 1.6 of the pre-inhibition zone 1 is preferably provided with several water distribution holes, and the effluent of the pre-inhibition zone 1 directly enters the anammox system 2 through the water distribution holes; There are no special requirements for the arrangement of the water holes, as long as the water can flow smoothly. In the present invention, the anammox system 2 is provided with a second aeration system 2.1 and an immobilized packing layer 2.2 in order from bottom to top; the anammox bacteria are attached to the immobilized packing layer 2.2. The present invention has no special requirements on the second aeration system 2.1, and an aeration system well known to those skilled in the art can be used. In the present invention, the immobilized filler layer 2.2 is preferably a polyurethane filler and/or a polypropylene filler. In the embodiment of the present invention, the immobilized filler layer 2.2 is a polyurethane filler, specifically a sponge filler; the immobilized filler The filling amount of the packing layer 2.2 is preferably 40-60% of the effective volume of the anammox system 2; the anammox bacteria are preferably one or more of Ca. Brocadia, Ca. Kuenenia and Ca. Anammoxoglobus.

In the present invention, the function of the anammox system 2 is to use denitrification bacteria (AOB) to convert NH ₄ ⁺ -N in the sewage into NO ₂ ^- -N, and the The ammonia oxidizing bacteria react NH ₄ ⁺ -N and NO ₂ ^- -N to generate nitrogen gas.

The device for anammox deep denitrification of industrial wastewater provided by the present invention includes an O ₁ AO ₂ denitrification zone 3, the water inlet end 3.8 of the O ₁ AO ₂ denitrification zone 3 and the anammox system 2 The water outlet end 2.4 is connected. In the present invention, the water outlet end 2.4 of the anammox system 2 is preferably provided with several water distribution holes, and the effluent of the anammox system 2 directly enters the O ₁ AO ₂ denitrification zone 3 through the water distribution holes. In the present invention, the O ₁ AO ₂ denitrification zone 3 includes a first aeration zone 3.1, anoxic zone 3.2 and a second aeration zone 3.3 connected in series; the first aeration zone 3.1 and the anaerobic zone 3.1 The water outlet 1.6 of the ammonia oxidation system 2 is connected; the water outlet 3.1.1 of the first aeration zone 3.1 and the water outlet 3.2.1 of the anoxic zone 3.2 are preferably provided with a number of water distribution holes, through which water distribution holes are provided. The holes realize the series connection of the first aeration zone 3.1, the anoxic zone 3.2 and the second aeration zone 3.3. In the present invention, the inner bottom of the first aeration zone 3.1 and the second aeration zone 3.3 are respectively provided with a third aeration system 3.4 and a fourth aeration system 3.6. There are no special requirements for the four aeration systems 3.6, and the aeration systems well known to those skilled in the art can be used. In the present invention, the anoxic area 3.2 is connected with a carbon source dosing system 3.7; the carbon source dosing system 3.7 is preferably arranged above the anoxic area 3.2, and the outlet of the carbon source dosing system 3.7 is connected to In the anoxic zone 3.2; the present invention has no special requirements on the structure of the carbon source dosing system 3.7, as long as the carbon source can be added; the anoxic zone 3.2 is also preferably provided with a stirrer 3.5. In the present invention, the second aeration zone 3.3 is provided with a water outlet 3.3.1; the second aeration zone 3.3 is also preferably provided with a water outlet return port 3.3.2, the water outlet return port and the pre-inhibition zone 1 The water inlet end 1.5 is connected; the connection pipeline between the water outlet return port 3.3.2 and the pre-suppression zone 1 is also preferably provided with a return pump 6, and the return pump 6 is connected with the online ammonia nitrogen analyzer 1.4 through a signal line. In the present invention, the reflux pump 6 is linked with the online ammonia nitrogen measuring instrument 1.4, and the reflux pump 6 can adjust the reflux amount of the mixed solution flowing out of the second aeration zone 3.3, and further control the ammonia nitrogen concentration in the pre-suppression zone within the set In the range.

In the present invention, the function of the first aeration zone 3.1 in the O ₁ AO ₂ denitrification zone 3 is to convert the remaining NH ₄ ⁺ -N of the anammox system 2 into NO ₂ ^- -N, and the anoxic zone 3.2 Its function is to denitrify NO ₂ ^- -N and NO ₃ ^- -N into nitrogen by adding a carbon source. The function of the second aeration zone 3.3 is to remove the remaining carbon source in the anoxic zone 3.2 by aeration to complete the system. deep denitrification.

The device for deep denitrification by anaerobic ammonium oxidation of industrial wastewater provided by the present invention includes a single sludge sedimentation tank system 4, and the water inlet 4.4 of the single sludge sedimentation tank system 4 is communicated with the water outlet 3.3.1 of the second aeration zone 3.3 . In the present invention, the single sludge sedimentation tank system 4 includes a sedimentation tank 4.1, a sludge outlet 4.2 arranged at the bottom of the sedimentation tank 4.1 and a water outlet 4.3 at the upper part, and the sludge outlet 4.2 branches into a sludge return port 4.2 .1 and the sludge discharge port 4.2.2, the sludge return port 4.2.1 is connected to the water inlet 1.5 of the pre-inhibition zone 1, and the sludge discharge port 4.2.2 discharges the sludge. The present invention has no special requirements on the structure of the sedimentation tank 4.1, and a sedimentation tank well known to those skilled in the art can be used. In the present invention, the pipelines of the sludge return port 4.2.1 and the sludge discharge port 4.2.2 are also preferably provided with a sludge return pump 7 and a sludge discharge pump 8 respectively; the sludge return pump 7 is preferably connected to The online ammonia nitrogen analyzer 1.4 is connected through a signal line. The present invention has no special requirements on the sludge return pump 7 and the sludge discharge pump 8, and pumps well known to those skilled in the art can be used.

In the present invention, the function of the sedimentation tank system 4 is to separate the effluent from the O ₁ AO ₂ denitrification zone 3 from mud and water.

The invention provides a method for deep denitrification by anaerobic ammonium oxidation of industrial wastewater, comprising the following steps:

(1) The industrial wastewater to be treated enters the pre-suppression zone 1, and is mixed with the return sludge from the sedimentation tank 4.1 through the sludge return port to the pre-suppression zone 1 under the action of the first aeration system 1.1. System 1.2 Adds alkaline substances to adjust the pH value in the pre-suppression zone 1 to 7.5-8.2, and the flow of the reflux sludge adjusts the ammonia nitrogen concentration in the pre-suppression zone 1 to be 200-500 mg/L, and the pH value and ammonia nitrogen concentration are monitored in real time by online pH analyzer 1.3 and online ammonia nitrogen analyzer 1.4 respectively;

(2) The wastewater treated by the pre-inhibition zone 1 enters the anaerobic ammonia oxidation system 2. Under the action of the second aeration system 2.1, the ammonia oxidizing bacteria convert the NH ₄ ⁺ -N in the wastewater into NO ₂ ^- - N, the anammox bacteria attached to the immobilized packing layer 2.2 react with NH ₄ ⁺ -N and NO ₂ ^- -N to generate nitrogen gas and NO ₃ ^- -N;

(3) The wastewater treated by the anammox system 2 enters the O ₁ AO ₂ denitrification zone 3, and under the action of the third aeration system 3.4 in the aeration zone 3.1, the remaining water in the anammox system 2 is removed. The NH ₄ ⁺ -N is nitrated to NO ₂ ^- -N;

The treated wastewater flowing out of the aeration zone 3.1 enters the anoxic zone 3.2, and the organic carbon source is added to the anoxic zone 3.2 through the carbon source dosing system 3.7 to denitrify NO ₂ ^- -N and NO ₃ ^- -N into nitrogen. ;

The treated wastewater flowing out of the anoxic zone 3.2 enters the second aeration zone 3.3, and the remaining organic carbon source in the anoxic zone 3.2 is removed under the action of the fourth aeration system 3.6;

(4) The wastewater treated by the second aeration zone 3.3 enters the single sludge sedimentation tank system 4, and the sludge is separated in the sedimentation tank 4.1. The separated sludge is partially returned to the pre-inhibition zone 1, and the rest is discharged from the sludge The outlet 4.2.2 is discharged, and the separated supernatant is discharged from the water outlet 4.3.

In the present invention, the industrial wastewater to be treated enters the pre-inhibition zone 1, and is mixed with the return sludge from the sedimentation tank 4.1 through the sludge return port 4.2.1 to the pre-inhibition zone 1 under the action of the first aeration system 1.1. , the pH value in the pre-suppression zone 1 is adjusted to 7.5-8.2 by adding alkaline substances to the alkali adding system 1.2, and the flow rate of the reflux sludge is adjusted to adjust the ammonia nitrogen concentration in the pre-suppression zone 1 to 200-500 mg/L, The pH value and the ammonia nitrogen concentration are monitored in real time by the online pH measuring instrument 1.3 and the online ammonia nitrogen measuring instrument 1.4 respectively, so that the nitrite oxidizing bacteria in the return sludge are inhibited and the ammonia oxidizing bacteria are proliferated. In the present invention, the industrial wastewater to be treated is preferably high ammonia nitrogen sewage, and the ammonia nitrogen concentration of the high ammonia nitrogen sewage is preferably greater than or equal to 500 mg/L. In the present invention, the alkaline substance is preferably sodium hydroxide, the pH value in the pre-inhibition zone 1 is preferably 7.8-8.0; the ammonia nitrogen concentration in the pre-inhibition zone 1 is preferably 300-400 mg/L The present invention optimizes bacterial species by controlling the pH value and ammonia nitrogen concentration in the pre-inhibition zone 1, suppresses the activity of (NOB), and promotes the growth of denitrifying bacteria (AOB).

In the present invention, when the flow rate of the backflow sludge from the sludge return port 4.2.1 to the pre-suppression zone 1 is not enough to dilute the ammonia nitrogen concentration of the industrial wastewater to be treated to the range value, the present invention It is also preferable to return the wastewater treated by the second aeration zone 3.3 to the pre-suppression zone 1 through the water outlet return port 3.3.2, that is, through the sludge return and the mixed liquid after the second aeration zone 3.3. Ammonia nitrogen concentration in inhibition zone 1.

In the present invention, the hydraulic retention time of the pre-inhibition zone 1 is preferably 30-60 min, more preferably 40-50 min; the temperature in the pre-inhibition zone 1 is preferably 28-32° C., more preferably 29 ~31°C.

In the present invention, the ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) are inoculated into the system from outside (such as activated sludge from general urban sewage plants or other industrial wastewater) in the early stage of system operation (such as Inoculated into pre-inhibition zone 1 or hypoxia zone 3.2), and gradually enriched and optimized in the system.

After the treatment of the pre-inhibition zone 1 is completed, the present invention will enter the wastewater treated by the pre-inhibition zone 1 into the anaerobic ammonia oxidation system 2. Under the action of the second aeration system 2.1, the ammonia oxidizing bacteria will remove the NH ₄ ⁺ in the wastewater. -N is converted into NO ₂ ^- -N, and the anammox bacteria attached to the immobilized packing layer 2.2 use NH ₄ ⁺ -N and NO ₂ ^- -N to react to generate nitrogen and NO ₃ ^- -N(NO ₃ ^- -N is produced in a small amount, and anammox produces about 11% of NO ₃ ^- -N). In the present invention, the dissolved oxygen in the anammox system 2 is preferably less than or equal to 0.5 mg/L. The anammox system 2 can achieve 80-85% TN (total nitrogen) removal through autotrophic nitrogen removal.

The short-range nitrification of the single-sludge system is difficult to control (NH ₄ ⁺ -N is difficult to stably convert into NO ₂ ^- -N), so the traditional systems are all double-sludge systems; the present invention sets a front end in the front end of the anammox system In the inhibition zone, the microorganisms are inhibited and washed by the substances in the influent water, the non-denitrifying bacteria are inhibited, the proliferation of ammonia oxidizing bacteria is maintained, and the short-range nitrification effect of the anammox system is stable, and the anammox system does not need to be set up Sludge sedimentation system.

After the anammox system 2 treatment is completed, the present invention will enter the wastewater treated by the anammox system 2 into the O ₁ AO ₂ denitrification zone 3, and under the action of the third aeration system 3.4 in the aeration zone 3.1, The NH ₄ ⁺ -N remaining in the anammox system 2 is nitrified to NO ₂ ^- -N. In the present invention, the ammonia nitrogen concentration in the first aeration zone 3.1 is preferably less than or equal to 5 mg/L.

After the treatment of the first aeration zone 3.1 is completed, the present invention enters the treated wastewater from the first aeration zone 3.1 into the anoxic zone 3.2, and the organic carbon source is added to the anoxic zone 3.2 through the carbon source dosing system 3.7, and NO ₂ ^- -N and NO ₃ ^- -N are denitrified into nitrogen gas. In the present invention, the organic carbon source preferably includes sodium acetate and/or methanol, and the organic carbon source provides a carbon source for the denitrification process as an electron donor for denitrifying bacteria; the addition amount of the organic carbon source is preferably It is 1.71 times the removal amount (concentration amount) of NO ₂ ^- -N or 2.86 times the removal amount of NO ₃ ^- -N.

After the treatment of the anoxic zone 3.2 is completed, the present invention enters the treated wastewater from the anoxic zone 3.2 into the second aeration zone 3.3, and the remaining organic carbon source in the anoxic zone 3.2 is removed under the action of the fourth aeration system 3.6. In the present invention, the dissolved oxygen (DO) of the second aeration zone 3.3 is preferably less than or equal to 2.0 mg/L.

Traditional double sludge system, deep denitrification relies on traditional nitrification and denitrification denitrification, generally AO system, the nitrification process converts NH ₄ ⁺ -N into NO ₃ ^- -N, and the denitrification process reduces NO ₃ ^- -N It is nitrogen; the present invention sets an O ₁ AO ₂ denitrification zone, which is a short-range nitrification and denitrification denitrification process. The short-range nitrification process converts NH ₄ ⁺ -N into NO ₂ ^- -N, and the denitrification process reduces NO ₂ ^- -N for nitrogen.

After the treatment in the second aeration zone 3.3 is completed, the present invention will enter the wastewater treated by the second aeration zone 3.3 into the single sludge sedimentation tank system 4, and carry out the mud-water separation in the sedimentation tank 4.1, and the separated sludge is partially returned to the pre-suppression tank. Zone 1, the rest are discharged from the sludge discharge port 4.2.2, and the separated supernatant is discharged from the water outlet 4.3. In the present invention, the reflux ratio of the sludge is preferably 0.5-1. In the present invention, the mixed solution treated by the second aeration zone 3.3 is also partially returned to the pre-suppression zone 1 through the water outlet return port 3.3.2 to further adjust the ammonia nitrogen concentration in the pre-suppression zone 1. The present invention only sets one sedimentation tank, which is a single-sludge system. Compared with the traditional double-sludge system, the present invention can save the sedimentation tank, the sludge return, sludge discharge, and water distribution system matched with the sedimentation tank, as well as the matching pumps, pipes, and control systems. And instruments and other equipment, only one set of precipitation system can achieve deep denitrification.

The invention provides a method for deep denitrification by anaerobic ammonium oxidation of industrial wastewater. By adopting the method provided by the invention to carry out deep denitrification by anaerobic ammonium oxidation of industrial wastewater, the removal rate of total nitrogen (TN) is above 97%. Most of the industrial sewage can meet the discharge standard after being treated by the device.

The device and method for deep denitrification by anammox of industrial wastewater provided by the present invention will be described in detail below with reference to the examples, but they should not be construed as limiting the protection scope of the present invention.

Example 1

A certain coal-to-ethylene glycol wastewater, the water volume is 4000m ³ /d, the ammonia nitrogen concentration is 500-1000mg/L, and the COD concentration is 500-1500mg/L, which is a typical low C/N process wastewater.

The coal chemical wastewater first enters the high-load aeration tank, and the refractory organic matter is removed in the high-load aeration tank. The effluent from the high-load aeration tank is subjected to deep denitrification and anaerobic ammonia oxidation using the device shown in Figure 2. The process is as follows :

The influent water (ie high-load aeration tank effluent) and the return sludge flowing out from the sedimentation tank 4.1 enter the pre-inhibition zone 1 and are mixed under the action of the first aeration system 1.1, and the sludge return is 4000-8000 m ³ /d, The ammonia nitrogen concentration in the pre-suppression zone 1 is controlled to 200mg/L, and the nitrifying liquid return system is not set up (that is, the ammonia nitrogen concentration in the pre-suppression zone is only adjusted by returning sludge). Alkali addition system 1.2 Add sodium hydroxide to control the pH value in the pre-inhibition zone 1 to be about 8.0, the hydraulic retention time is 30min, and the temperature is 30～32℃;

The mixed liquid in the pre-inhibition zone flows through the anammox system 2, and the immobilized packing layer 2.2 is installed in this zone, and the anammox bacteria (Ca. Brocadia, Ca. Kuenenia and Ca. Anammoxoglobus, Ca. Brocadia) are attached to the packing Mainly), the second aeration system 2.1 is set up in this area, DO (dissolved oxygen) is controlled below 0.5mg/L, ammonia oxidizing bacteria (Nitrosomonas, Nitrosomonas) will NH ₄ ⁺ -N in the mixture It is converted into NO ₂ ^- -N, and the anammox bacteria attached to the immobilized packing layer 2.2 use NH ₄ ⁺ -N and NO ₂ ^- -N to react to generate nitrogen and a small amount of NO ₃ ^- -N;

The mixed liquid of the anammox system 2 enters the O ₁ AO ₂ denitrification zone 3, and the remaining NH ₄ ⁺ -N of the anammox system 2 is converted into NO ₂ ^- -N in the aeration zone 3.1, and the ammonia nitrogen concentration Controlled to be less than 5mg/L; add a small amount of external carbon source (methanol) in the anoxic zone 3.2 to denitrify NO ₂ ^- -N and NO ₃ ^- -N into nitrogen; finally, in the second aeration zone 3.3, the excess dose is added. The added carbon source is removed by aeration, the dissolved oxygen is controlled to be less than 2.0mg/L, and the deep denitrification of the system is completed;

The effluent from O ₁ AO ₂ denitrification zone 3 enters sedimentation tank 4.1 for mud-water separation, and part of the separated sludge is returned to pre-suppression zone 1, and the rest is discharged from the sludge discharge port, and the separated clean water is discharged from the clean water outlet 4.3.

Nitrosomonas (ammonia oxidizing bacteria, Nitrosomonas) is an AOB genus, and it is also the main functional bacteria in the short-range nitrification process. The main function of AOB is to convert NH ₄ ⁺ -N into NO ₂ ^- -N, and AOB is the dominant strain The system shows that the system has a good short-range nitrification effect. Through the detection of microorganisms in the stable operation system, the abundance of Nitrosomonas in the suspended mud samples in the pre-inhibition zone 1 is 8.3% to 10.6%, and the average abundance is 9.5%; the abundance of Nitrosomonas on the immobilized packing layer 2.2 is far less than 1%. That is to say, the abundance of Nitrosomonas in the suspended mud samples is much greater than that in the immobilized packing layer. This result shows that the setting of the pre-inhibition zone can effectively wash out the proliferation of NOB (nitrite oxidizing bacteria) in the system and promote the The stable proliferation of dominant bacteria such as Nitrosomonas bacteria in the system was achieved, and a stable short-range nitrification effect was achieved.

At the same time, the abundance of Ca.Brocadia on the immobilized packing layer of the anammox system of the system is 1.9% to 23.2%, and the average abundance is 9.1%. In the process of treating coal-to-ethylene glycol wastewater, anaerobic ammonia The oxidizing bacteria, Ca. Brocadia, was enriched on the sponge filler and formed the dominant bacteria, while the content in the suspended mud was less. The abundance of Ca.Kuenenia in the suspended mud samples was 0.9%-2.5%, with an average abundance of 1.9%; the abundance of Ca.Kuenenia on the immobilized packing layer was 1.6%-10.5%, with an average abundance of 5.0%; Ca. The distribution of .Anammoxoglobus on the suspended mud and filler has no obvious difference, and the abundance is 1.1%～13.2%. Representative anammox bacteria such as Ca.Brocadia, Ca.Kuenenia and Ca.Anammoxoglobus are in the system A large amount of enrichment, through the anaerobic ammonium oxidation pathway, converts ammonia nitrogen and nitrite nitrogen into nitrogen, and realizes the autotrophic denitrification of the system.

During the stable operation of the system, the influent ammonia nitrogen concentration was 500-1000 mg/L, the anaerobic ammonia oxidation denitrification load was 0.3-0.5 kg/m ³ /d, and ΔNO ₃ ^- -N/ΔNH ₄ ⁺ -N was always lower than 0.11. The ammonia nitrogen concentration of the mixed liquid at the end of ANAMMOX is less than 30mg/L, the nitrate nitrogen concentration is 50-80mg/L, and the nitrite nitrogen concentration is 30-50mg/L; the deep denitrification unit (ie the O ₁ AO ₂ denitrification zone ) effluent ammonia nitrogen concentration is less than 5mg/L, nitrate nitrogen concentration is less than 5mg/L, nitrite nitrogen concentration is less than 3mg/L, TN is less than 15mg/L, and the average total nitrogen removal rate is greater than 97%.

It can be seen from the above embodiments that the device provided by the present invention is a single sludge precipitation system, which can ensure the stability of the system while reducing the process complexity and operating cost. The device provided by the present invention is used for deep denitrification of industrial wastewater. Anaerobic ammonia oxidation, the total nitrogen (TN) removal rate is above 97%.

The descriptions of the above embodiments are only used to help understand the method and the core idea of the present invention. It should be pointed out that for those skilled in the art, without departing from the principle of the present invention, several improvements and modifications can also be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (13)

1. A device for deep denitrification by anaerobic ammonium oxidation of industrial wastewater, characterized in that it comprises:

   A pre-inhibition zone (1), the pre-inhibition zone (1) includes a water inlet end (1.5) and a water outlet end (1.6), and a first aeration system ( 1.1), the pre-inhibition zone (1) is communicated with an alkali adding system (1.2); the pre-inhibition zone (1) is also provided with an online pH measuring instrument (1.3) and an online ammonia nitrogen measuring instrument (1.4), The online pH measuring instrument (1.3) is simultaneously connected with the alkali adding system (1.2) through a signal line;

   The anaerobic ammonium oxidation system (2) is communicated with the water inlet end (2.3) and the water outlet end (1.6) of the pre-inhibition zone (1). The anaerobic ammonium oxidation system (2) is sequentially provided with The second aeration system (2.1) and the immobilized packing layer (2.2), the anammox bacteria are attached to the immobilized packing layer (2.2);

   an O ₁ AO ₂ denitrification zone (3) in which the water inlet end (3.8) is communicated with the outlet end (2.4) of the anammox system (2), and the O ₁ AO ₂ denitrification zone (3) comprises a The first aeration zone (3.1), the anoxic zone (3.2) and the second aeration zone (3.3) connected in series; the first aeration zone (3.1) and the water outlet of the anammox system (2) (2.4) Communication, the inner bottom of the first aeration zone (3.1) and the second aeration zone (3.3) are respectively provided with a third aeration system (3.4) and a fourth aeration system (3.6); the anoxic zone (3.2) A carbon source dosing system (3.7) is connected; the second aeration zone (3.3) is provided with a water outlet (3.3.1);

   A single sludge sedimentation tank system (4) in which the water inlet (4.4) is communicated with the water outlet (3.3.1) of the second aeration zone (3.3), the single sludge sedimentation tank system (4) includes a sedimentation tank ( 4.1), the sludge outlet (4.2) at the bottom of the sedimentation tank (4.1) and the water outlet (4.3) at the upper part, the sludge outlet (4.2) is branched into the sludge return port (4.2.1) and the sludge discharge port (4.2.2), the sludge return port (4.2.1) is communicated with the water inlet end (1.5) of the pre-inhibition zone (1).
2. The device according to claim 1, characterized in that, a stirrer (3.5) is further provided in the anoxic zone (3.2).
3. The device according to claim 1, wherein the immobilized filler layer (2.2) is a polyurethane filler and/or a polypropylene filler; the filling amount of the immobilized filler layer (2.2) is an anammox system (2) 40-60% of the effective volume.
4. The device according to claim 1, characterized in that, the second aeration zone (3.3) is further provided with a water outlet return port (3.3.2), the water outlet return port (3.3.2) and the pre-inhibition zone (3.3.2). 1) is communicated with the water inlet (1.5); a return pump (6) is provided on the connection pipeline between the water outlet return port (3.3.2) and the pre-inhibition zone (1). The ammonia nitrogen analyzer (1.4) is connected through the signal line.
5. The device according to claim 1 or 4, characterized in that, the water outlet end (1.6) of the pre-inhibition zone (1) is provided with a plurality of water distribution holes.
6. The device according to claim 1 or 4, characterized in that, (2.4) of the anammox system (2) is provided with a plurality of water distribution holes.
7. The device according to claim 1, characterized in that, a sludge return pump (7) and a drain pump are respectively provided on the pipelines of the sludge return port (4.2.1) and the sludge discharge port (4.2.2). A mud pump (8); the sludge return pump (7) is connected with the online ammonia nitrogen measuring instrument (1.4) through a signal line.
8. A method for deep denitrification by anaerobic ammonium oxidation of industrial wastewater, comprising the following steps:

   (S1) The industrial wastewater to be treated enters the pre-suppression zone (1), and the backflow sludge from the sedimentation tank (4.1) through the sludge return port (4.2.1) to the pre-suppression zone (1) is in the first exposure zone. Mixing under the action of the gas system (1.1), the pH value in the pre-suppression zone (1) is adjusted to 7.5-8.2 by adding an alkaline substance to the alkali-adding system (1.2), and the flow of the backflow sludge is adjusted to the pre-suppression The ammonia nitrogen concentration in the area (1) is 200-500 mg/L, and the pH value and the ammonia nitrogen concentration are respectively monitored in real time by an online pH measuring instrument (1.3) and an online ammonia nitrogen measuring instrument (1.4);

   (S2) The wastewater treated by the pre-inhibition zone (1) enters the anaerobic ammonia oxidation system (2), and under the action of the second aeration system (2.1), the ammonia oxidizing bacteria remove the NH ₄ ⁺ -N in the wastewater It is converted into NO ₂ ^- -N, and the anammox bacteria attached to the immobilized packing layer (2.2) use NH ₄ ⁺ -N and NO ₂ ^- -N to react to generate nitrogen gas and NO ₃ ^- -N;

   (S3) The wastewater treated by the anammox system (2) enters the O ₁ AO ₂ denitrification zone (3), and under the action of the third aeration system (3.4) in the first aeration zone (3.1), the The remaining NH ₄ ⁺ -N in the anammox system (2) is nitrified to NO ₂ ^- -N;

   The treated wastewater flowing out of the first aeration zone (3.1) enters the anoxic zone (3.2), and the organic carbon source is added to the anoxic zone (3.2) through the carbon source dosing system (3.7), and NO ₂ ^- -N and NO ₃ ^- -N denitrification into nitrogen;

   The treated wastewater flowing out of the anoxic zone (3.2) enters the second aeration zone (3.3), and the remaining organic carbon source in the anoxic zone (3.2) is removed under the action of the fourth aeration system (3.6);

   (S4) The wastewater treated by the second aeration zone (3.3) enters the single sludge sedimentation tank system (4), the sludge is separated in the sedimentation tank (4.1), and the separated sludge is partially returned to the pre-suppression zone (S4). 1), the rest are discharged from the sludge discharge port (4.2.2), and the separated supernatant is discharged from the water outlet (4.3).
9. The method according to claim 8, characterized in that, the wastewater treated by the second aeration zone (3.3) is also partially returned to the pre-suppression zone (1) through the outlet return port (3.3.2).
10. The method according to claim 8, characterized in that, in the step (1), the hydraulic retention time of the pre-inhibition zone (1) is 30-60 min; the temperature in the pre-inhibition zone (1) is 28 ~32°C.
11. The method according to claim 8, wherein the dissolved oxygen in the anaerobic ammonia oxidation system (2) in the step (2) is less than or equal to 0.5 mg/L.
12. The method according to claim 8, characterized in that, in the step (3), the ammonia nitrogen concentration in the first aeration zone (3.1) is less than or equal to 5 mg/L; The carbon source includes sodium acetate and/or methanol; the added amount of the organic carbon source is 1.71 times the removal amount of NO ₂ ^- -N or 2.86 times the removal amount of NO ₃ ^- -N; the second zone of aeration (3.3) The dissolved oxygen inside is less than or equal to 2.0mg/L.
13. The method according to claim 8, wherein the reflux ratio of the sludge in the step (3) is 0.5-1.

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