CN111285461A - A system and operation method for realizing enhanced deep bed denitrification filter denitrification - Google Patents

Abstract

A system for realizing enhanced denitrification in a deep bed denitrification filter tank, comprising a deep bed denitrification filter tank, an active coke adsorption tank and a clear water tank; the deep bed denitrification filter tank is divided into a pre-filtration area and a main filter for denitrification. The outlet of the pre-filtration area is connected to the inlet of the main filter and denitrification area. The pre-filtration area is provided with a carbon source feeding point, the inlet is provided with an online turbidity detector and a nitrate nitrogen detector, and the main filter and denitrification area is provided with carbon source. The source feeding point, the inlet and outlet are respectively provided with an online COD detector, the water outlet is provided with an online nitrate nitrogen detector, and the water outlet of the activated coke adsorption tank is provided with an online COD detector; The outlet is connected with the inlet of the active coke adsorption tank or directly connected with the inlet of the clean water tank, and the outlet of the active coke adsorption tank is connected with the inlet of the clean water tank. The system improves the utilization efficiency of carbon sources, improves the flexibility of adding carbon sources during the unstable period of denitrification, and strengthens the denitrification effect of the deep bed filter.

Description

A system and operation method for realizing enhanced deep bed denitrification filter denitrification

technical field

The invention belongs to the technical field of water treatment, and relates to a system and an operation method for realizing enhanced denitrification in a deep-bed denitrification filter.

Background technique

With the continuous improvement of the demand for water environment quality improvement, the pollutant discharge standards of urban sewage treatment plants in my country have been continuously improved. TN is one of the key factors of water eutrophication. In the local standards issued by Beijing, Tianjin, Zhejiang, Jiangsu and other provinces and cities successively, TN is proposed to be more stringent than the "Pollutant Discharge Standard for Urban Sewage Treatment Plants" (GB18918-2002). strict requirements. For example, Beijing's "Comprehensive Discharge Standard of Water Pollutants" (DB11/307-2013) and Tianjin's "Pollutant Discharge Standard for Urban Sewage Treatment Plants" (DB12/599-2015), respectively, are aimed at discharging into Class II, Class III water bodies and For the sewage within its catchment range and the effluent from urban sewage treatment plants with a design scale of ≥10000m ³ /d, a discharge standard of TN lower than 10mg/L is proposed, and COD is required to be lower than 20mg/L and 30mg/L respectively. Nitrogen removal in sewage treatment plants puts forward high demands.

The deep bed denitrification filter is an advanced treatment process that came into being in order to meet the "Pollutant Discharge Standards for Urban Sewage Treatment Plants" (GB18918-2002) Level A. After being applied to the sedimentation treatment process, quartz sand is used as the filter material. It can simultaneously remove nitrogen while removing suspended solids, and has been widely used in the advanced treatment process of urban sewage treatment plants in my country.

The operation practice of the deep bed denitrification filter shows that when the effluent of the sedimentation tank, that is, the concentration of suspended solids in the influent water of the filter, fluctuates and impacts, the backwashing process that is frequently started in the deep bed filter causes the biofilm growing on the surface of the quartz sand to be destroyed, and the reverse In addition to the affected nitrification effect, the falling biofilm is also likely to cause the overall quality of the filter effluent to exceed the standard; it also often occurs that the total amount of microorganisms in the startup period is low due to the need to consider the effluent COD to meet the standard, and the microbial activity function is reduced during the low temperature period in winter. In the case of low temperature, a sufficient amount of carbon source cannot be added, resulting in a long denitrification start-up period and a decrease in the removal of TN in the low temperature period.

Therefore, under the high TN standard of the effluent and the strict requirements of COD, it is necessary to propose a process and method to realize the enhanced denitrification of the deep bed denitrification filter while ensuring the COD of the effluent.

SUMMARY OF THE INVENTION

In order to solve the above-mentioned technical problems existing in the deep-bed sand filter provided with the denitrification function, the present invention provides a system for realizing the enhanced denitrification of the deep-bed denitrification filter, which improves the utilization efficiency of carbon sources and improves the efficiency of denitrification. The growth environment of denitrifying microorganisms improves the flexibility of adding carbon sources during the unstable period of denitrification, and strengthens the denitrification effect of the deep bed filter.

Another object of the present invention is to provide the above-mentioned method for realizing the system of strengthening the denitrification of the deep bed denitrification filter.

In order to solve the above-mentioned technical problems, the technical scheme adopted in the present invention is: a system for realizing enhanced deep-bed denitrification filter denitrification, which is characterized in that: it includes a deep-bed denitrification filter, an activated coke adsorption tank and a clear water tank; The deep bed denitrification filter tank is divided into a pre-filtration area and a main filter and denitrification area. The outlet of the pre-filtration area is connected with the inlet of the main filter and denitrification area. The main filter and denitrification zone is equipped with a carbon source feeding point, the inlet and outlet are respectively equipped with an online COD detector, and the water outlet is equipped with an online nitrate nitrogen detector. The water outlet is provided with an on-line COD detector; the outlet of the deep bed denitrification filter is connected to the inlet of the active coke adsorption tank or is directly connected to the inlet of the clean water tank, and the outlet of the active coke adsorption tank is connected to the inlet of the clean water tank .

The pre-filtration area of the deep-bed denitrification filter tank and the main body of the main filter denitrification area are separated by a permeable partition.

The empty bed volume ratio of the pre-filtration zone and the main filter denitrification zone of the deep-bed denitrification filter tank is 1:4 to 1:5.

The pre-filtration area of the deep-bed denitrification filter is filled with biological ceramsite, and the particle size is 3-5 mm.

A three-way valve is arranged on the outlet pipe of the main filter and denitrification zone of the deep bed denitrification filter tank. An on-off valve is provided.

The main filter and denitrification zone of the deep bed denitrification filter tank uses quartz sand as the filter material, and the particle size is 1.5-3.5mm.

The activated coke adsorption tank has a filtration rate of 8-10 m/h and a height of 2.0-2.5 m.

The activated coke filled in the activated coke adsorption tank is coal-made granular activated coke, the particle size is 4-10 mm, and the iodine value is ≥500 mg/g.

Separate water reactors are respectively provided between the clear water tank and the pre-filtration area of the deep bed denitrification filter tank, between the clear water tank and the main filter denitrification area of the deep bed denitrification filter tank, and between the clear water tank and the active coke adsorption tank. wash the system.

The pre-filtration area, the main filter denitrification area and the activated coke adsorption tank of the deep-bed denitrification filter tank are respectively provided with separate air washing systems.

The above-mentioned operation method for realizing the system for strengthening the denitrification of deep bed denitrification filter tank comprises the following steps:

a. The water to be treated enters the pre-filtration area of the deep bed denitrification filter through the water inlet pipe, and passes from top to bottom at a filtration rate of 5-8m/h. The influent turbidity is detected in real time by an online turbidity detector, and the The carbon source is added at the dosing point, and the carbon source dosing ratio in this area is adjusted between 0 and 20% according to the turbidity of the influent water; when the influent turbidity is ≥ 8NTU, no carbon source is added in this area, and it only plays a role in reducing the amount of water entering the main area. The effect of the concentration of suspended solids in the filter and denitrification zone; when the influent turbidity is less than 8NTU, in addition to reducing the concentration of suspended solids in this area under the condition of adding a carbon source, the microorganisms growing on the surface of the ceramsite also have denitrification and denitrification;

b. The water obtained in step a enters the main filter and denitrification zone of the deep bed filter through the permeable partition wall, passes from top to bottom at a filtration rate of 5-8m/h, and adds the carbon source through the carbon source adding point. When the addition ratio is between 80% and 100%, nitrogen is removed by denitrification of microorganisms growing on the surface of quartz sand, and suspended solids are removed by interception and adsorption between quartz sands;

c. The water obtained in step b determines whether the activated coke adsorption tank is overrunning according to the concentration of COD in its effluent. When the COD is higher than the target set value, the valve on the pipeline between the outlet of the deep bed denitrification filter and the inlet of the clean water tank is closed , the valve on the pipeline between the outlet of the deep bed denitrification filter and the inlet of the active coke adsorption tank is opened, and the water obtained in step b enters the active coke adsorption tank through the pipeline, and passes through the active coke adsorption from bottom to top at a filtration rate of 8-10m/h. The removal of organic matter is completed in the tank, which provides a guarantee for the COD standard of the effluent during the denitrification start-up period and the initial low temperature period when the denitrification function is unstable;

When the COD is lower than the target set value, the valve on the pipeline between the outlet of the deep bed denitrification filter and the inlet of the activated coke adsorption tank is closed, and the valve on the pipeline between the outlet of the deep bed denitrification filter and the inlet of the clean water tank is opened, Activated coke adsorption pool overruns;

d. The water obtained in step c enters the clear water tank through the outlet and then is discharged.

Compared with the prior art, the present invention has the following advantages and positive effects:

1. The present invention divides the deep-bed denitrification filter into a pre-filtration area and a main filter denitrification area, and sets up an independent backwash system. During the period when the concentration of the influent suspended solids is relatively high, the influent suspended solids are treated by the pre-filtration area. The counteracting effect of concentration shock can reduce the number of backwashing in the main filter denitrification zone, avoid the impact of frequent backwashing on the surface biomass of quartz sand, and provide favorable conditions for sufficient biomass for denitrification in the main filter zone of the filter.

2. The present invention divides the deep-bed denitrification filter into a pre-filtration area and a main filter denitrification area. Both areas are provided with carbon source dosing points, which can flexibly adjust the carbon source dosing in the two areas according to changes in influent turbidity. When the environment of the pre-filtration area is poor, no carbon source is added to avoid the consumption of carbon source. When the concentration of suspended solids in the influent is low, both the pre-filtration area of the filter tank and the denitrification area of the main filter can play the role of denitrification and denitrification. The method is flexible to realize the optimal utilization of external carbon sources.

3. In the present invention, an activated coke adsorption tank is set behind the deep bed denitrification filter, and it can be determined whether it exceeds the operation according to the level of COD concentration in the effluent of the filter. In the stable period, the COD of the effluent is guaranteed to meet the standard, which improves the flexibility of adding carbon sources to the deep bed denitrification filter, and provides a flexible space for the operation of the deep bed denitrification filter.

4. The volume ratio of the empty bed between the pre-filtration zone and the main filter denitrification zone of the deep-bed denitrification filter in the present invention is 1:4 to 1:5. When applied to the reconstruction of the deep-bed filter, the height of the deep-bed filter is generally It is 1.8-2.4m. After reducing the height of the filter column in the main filter area, the ceramsite in the pre-filter area can also play a filtering role. In addition to strengthening the denitrification effect, it will not affect the concentration of suspended solids in the effluent. The height of biological ceramsite is only 0.4-0.5m, which can be supported by a permeable partition with a stainless steel skeleton, and the main structure does not need to be changed during application.

Description of drawings

Fig. 1 is the process flow schematic diagram of the present invention.

In the figure: 1-water to be treated; 2-deep bed denitrification filter; 2-1 deep bed denitrification filter pre-filtration zone; 2-2 deep bed denitrification filter main filter denitrification zone; 3-active coke Adsorption tank; 4-Clear water tank; 5-Effluent; 6-Carbon source addition point in pre-filtration area; 7-On-line turbidity detector; 8-On-line nitrate nitrogen detector; 9-On-line COD detector; 10-Main filter 11-On-line COD detector; 12-On-line nitrate nitrogen detector; 13-On-line COD detector; 14-Water backwashing system in pre-filtration zone; 15-Water backwashing system in main filter and denitrification zone ; 16- Active coke adsorption tank water backwash system; 17- Pre-filtration zone gas backwash system; 18- Main filter denitrification zone gas backwash system; 19- Active coke adsorption tank gas backwash system.

Detailed ways

As shown in Figure 1, a system for realizing enhanced denitrification by a deep bed denitrification filter includes a deep bed denitrification filter (2), an activated coke adsorption pool (3) and a clean water pool (4).

The deep bed denitrification filter tank (2) is divided into a pre-filtration zone (2-1) and a main filter denitrification zone (2-2) by a permeable partition plate, and the outlet of the pre-filtration zone (2-1) and the main denitrification zone (2-1). The inlet of the filter-denitrification zone (2-2) is connected, the pre-filtration zone (2-1) is provided with a carbon source feeding point (6), and the inlet is provided with an online turbidity detector (7) and a nitrate nitrogen detector (8). ), the main filter denitrification zone (2-2) is provided with a carbon source dosing point (10), the inlet and outlet are respectively provided with online COD detectors (9) and (11), and the water outlet is provided with an online nitrate nitrogen detector ( 12), the water outlet of the active coke adsorption tank (3) is provided with an online COD detector (13); on the water outlet pipe of the main filter denitrification zone (2-2) of the deep bed denitrification filter tank (2) A three-way valve is provided, and the water outlet pipes of the two branches are respectively connected to the inlet of the activated coke adsorption tank (3) and the inlet of the clean water tank (4). The outlet of the bed denitrification filter is connected to the inlet of the active coke adsorption tank (3), or the outlet of the deep bed denitrification filter is directly connected to the inlet of the clean water tank. The outlet of the active coke adsorption tank (3) is connected to the clean water tank (3). 4) The inlet connection.

The deep bed denitrification filter tank (2) is provided with a prefiltration zone (2-1) and a main filter denitrification zone (2-2), and the empty bed volume ratio of the two zones is 1:4 to 1:5.

The pre-filtration zone (2-1) of the deep-bed denitrification filter (2) is filled with biological ceramsite, and the particle size is 3-5 mm.

In the main filter and denitrification zone (2-2) of the deep bed denitrification filter tank (2), quartz sand is used as the filter material, and the particle size is 1.5-3.5 mm.

The activated coke adsorption tank (3) has a filtration rate of 8-10 m/h and a height of 2.0-2.5 m.

The activated coke filled in the activated coke adsorption tank (3) is coal-made granular activated coke, the particle size is 4-10 mm, and the iodine value is ≥500 mg/g.

The online turbidity detector set at the inlet of the pre-filtration zone of the deep-bed denitrification filter is used to guide the distribution of the carbon source dosing ratio between the two carbon source dosing points. The main filter of the deep-bed denitrification filter The online COD detector set at the outlet of the nitrification zone is used to determine whether the activated coke adsorption tank is overrunning; the online nitrate nitrogen detector set at the inlet of the prefiltration zone, the online COD detector set at the inlet of the main filter denitrification zone and the outlet The online nitrate nitrogen detector is used to assist in determining the amount of external carbon source and analyzing the denitrification effect of the filter.

Separate water is provided between the clear water tank and the pre-filtration area of the deep bed denitrification filter tank, between the clear water tank and the main filter denitrification area of the deep bed denitrification filter tank, and between the clear water tank and the active coke adsorption tank. Backwash systems (14), (15) and (16).

Separate air washing systems (17), (18) and (19) are respectively provided in the pre-filtration area, the main filter denitrification area and the activated coke adsorption tank of the deep bed denitrification filter tank.

In the present invention, carbon source dosing points are set in both the pre-filtration area and the main filter denitrification area of the deep-bed denitrification filter, and the carbon source dosing ratio of the two points is flexibly adjusted according to the turbidity of the influent water, and the carbon source dosing in the pre-filtration area is flexibly adjusted. The ratio is between 0 and 20%, and the main filter and denitrification zone is between 80 and 100%. When the influent turbidity is ≥8NTU, no carbon source is added to the pre-filter zone, and all carbon sources are added to the denitrification main filter zone. .

Further, according to the level of COD concentration in the effluent of the deep bed denitrification filter, it is determined whether the activated coke adsorption tank is overrunning. When the COD is higher than the target value, the effluent of the deep bed denitrification filter enters the activated coke adsorption tank, and enters clean water after adsorption. When the COD is lower than the target value, the effluent of the deep bed denitrification filter directly enters the clean water tank, and the active coke adsorption tank runs beyond.

When the COD is lower than the target set value, the valve on the pipeline between the outlet of the main filter denitrification zone of the deep bed denitrification filter and the inlet of the activated coke adsorption tank is closed, and the valve between the outlet of the deep bed denitrification filter and the inlet of the clean water tank is closed. The valve on the pipeline is opened, and the activated coke adsorption tank is overrunning.

The operating method steps of the above-mentioned system for realizing enhanced deep-bed denitrification filter denitrification are as follows:

Embodiment 1:

a. The water to be treated (1) enters the pre-filtration zone (2-1) of the deep bed denitrification filter through the water inlet pipe, passes from top to bottom at a filtration rate of 5-8m/h, and passes through the online turbidity detector (7). ) Real-time monitoring of turbidity, when the influent turbidity is lower than 2NTU, add carbon source through the carbon source dosing point (6), control the carbon source dosing ratio in this area to 20%, reduce the suspended solids entering the main filter denitrification zone In addition to the concentration, the microorganisms growing on the surface of the ceramsite use the external carbon source to carry out the denitrification reaction;

b. The water obtained in step a enters the main filter denitrification zone (2-2) of the deep bed filter through the permeable partition wall, passes from top to bottom at a filtration rate of 5-8m/h, and is monitored in real time by an online COD detector (9). COD concentration, carbon source dosing point (10) add carbon source, control the proportion of carbon source dosing in this area to 80%; continue to denitrify by microbial denitrification growing on the surface of the quartz sand, and pass the retention adsorption between the quartz sands Remove suspended solids;

c. The water obtained in step b is monitored for COD in real time by an online COD monitor (11). When the COD of the effluent is higher than the target value, the valve on the pipeline between the outlet of the deep bed denitrification filter and the inlet of the activated coke adsorption tank is opened, and the deep bed is opened. The valve on the pipeline between the outlet of the denitrification filter and the inlet of the clean water tank is closed, and the water obtained in step b enters the active coke adsorption tank through the pipeline, and passes through the active coke adsorption tank from bottom to top at a filtration rate of 8 to 10 m/h. remove;

d. The water obtained in step c enters the clear water tank through the outlet and is then discharged;

Among them, the dosage of COD is comprehensively determined according to the detection results of the online nitrate nitrogen detector set at the inlet of the pre-filtration zone, the online COD detector set at the inlet of the main filter denitrification zone and the online nitrate nitrogen detector set at the outlet;

Further, the gas-water backwashing of the pre-filtering area of the deep-bed denitrification filter tank, the main filter denitrification area and the activated coke adsorption tank is performed respectively according to the pressure difference change in each tank body, and the backwashing drainage of the main filter and denitrification area is performed. It can be discharged through the drain in this area and the pre-filtering area.

Embodiment 2:

a. The water to be treated (1) enters the pre-filtration zone (2-1) of the deep bed denitrification filter through the water inlet pipe, and passes from top to bottom at a filtration rate of 5-8m/h. The influent water online turbidity detector ( 7) Real-time monitoring of turbidity, when the influent turbidity is 2-4 NTU, add carbon source through the carbon source dosing point (6), control the carbon source dosing ratio in this area to 10%, and reduce the rate of entering the main filter denitrification zone In addition to the concentration of suspended solids, the microorganisms growing on the surface of the filler use the external carbon source to carry out the denitrification reaction;

b. The water obtained in step a enters the main filter denitrification zone (2-2) of the deep bed filter through the permeable partition wall, passes from top to bottom at a filtration rate of 5-8m/h, and is monitored in real time by an online COD detector (9). COD concentration, carbon source dosing point (10) add carbon source, control the proportion of carbon source dosing in this area to 90%; continue to denitrify by microbial denitrification growing on the surface of quartz sand, and pass the retention adsorption between quartz sands Remove suspended solids;

c. The water obtained in step b is subjected to real-time monitoring of COD through the online COD monitor (11). When the effluent COD is lower than the target value, the valve on the pipeline between the outlet of the deep bed denitrification filter and the inlet of the clean water tank is opened, and the deep bed denitrification The valve on the pipeline between the outlet of the filter tank and the inlet of the activated coke adsorption tank is closed, and the water obtained in step b directly enters the clear water tank through the pipeline and then is discharged;

Among them, the dosage of COD is comprehensively determined according to the detection results of the online nitrate nitrogen detector set at the inlet of the pre-filtration zone, the online COD detector set at the inlet of the main filter denitrification zone and the online nitrate nitrogen detector at the outlet;

Further, the gas-water backwashing of the pre-filtering area of the deep-bed denitrification filter tank, the main filter denitrification area and the activated coke adsorption tank is performed respectively according to the pressure difference change in each tank body, and the backwashing drainage of the main filter and denitrification area is performed. It can be discharged through the drain in this area and the pre-filtering area.

Embodiment 3:

a. The water to be treated (1) enters the pre-filtration zone (2-1) of the deep bed denitrification filter through the water inlet pipe, and passes from top to bottom at a filtration rate of 5-8m/h. The influent water online turbidity detector ( 7) Real-time monitoring of turbidity, when the influent turbidity is 4-8 NTU, add carbon source through the carbon source dosing point (6), control the carbon source dosing ratio in this area to 5%, and reduce the rate of entering the main filter denitrification zone In addition to the concentration of suspended solids, the microorganisms growing on the surface of the filler use the external carbon source to carry out the denitrification reaction;

b. The water obtained in step a enters the main filter denitrification zone (2-2) of the deep bed filter through the permeable partition wall, passes from top to bottom at a filtration rate of 5-8m/h, and is monitored in real time by an online COD detector (9). COD concentration, carbon source dosing point (10) add carbon source, control the proportion of carbon source dosing in this area to 95%; denitrification by microorganisms growing on the surface of quartz sand denitrification, and through the retention and adsorption between quartz sands remove suspended solids;

c. The water obtained in step b is monitored for COD in real time by an online COD monitor (11). When the COD of the effluent is higher than the target value, the valve on the pipeline between the outlet of the deep bed denitrification filter and the inlet of the activated coke adsorption tank is opened, and the deep bed is opened. The valve on the pipeline between the outlet of the denitrification filter and the inlet of the clean water tank is closed, and the water obtained in step b enters the active coke adsorption tank through the pipeline, and passes through the active coke adsorption tank from bottom to top at a filtration rate of 8 to 10 m/h. remove;

d. The water obtained in step c enters the clear water tank through the outlet and is then discharged;

Among them, the dosage of COD is comprehensively determined according to the detection results of the online nitrate nitrogen detector set at the inlet of the pre-filtration zone, the online COD detector set at the inlet of the main filter denitrification zone and the online nitrate nitrogen detector at the outlet;

Further, the gas-water backwashing of the pre-filtering area of the deep-bed denitrification filter tank, the main filter denitrification area and the activated coke adsorption tank is performed respectively according to the pressure difference change in each tank body, and the backwashing drainage of the main filter and denitrification area is performed. It can be discharged through the drain in this area and the pre-filtering area.

Embodiment 4:

a. The water to be treated (1) enters the pre-filtration zone (2-1) of the deep bed denitrification filter through the water inlet pipe, and passes from top to bottom at a filtration rate of 5-8m/h. The influent water online turbidity detector ( 7) Real-time monitoring of turbidity, when the influent turbidity is higher than 8NTU, no carbon source is added to this area, and it only plays the role of reducing the concentration of suspended solids entering the main filter denitrification area;

b. The water obtained in step a enters the main filter denitrification zone (2-2) of the deep bed filter through the permeable partition wall, passes from top to bottom at a filtration rate of 5-8m/h, and is monitored in real time by an online COD detector (9). COD concentration, carbon source adding point (10) add carbon source, control the carbon source dosing ratio in this area to be 100%, mainly denitrification by microorganisms growing on the surface of quartz sand in this area, and denitrification by denitrification between the quartz sands. Intercept adsorption to remove suspended solids;

c. The water obtained in step b is subjected to real-time monitoring of COD through the online COD monitor (11). When the effluent COD is lower than the target value, the valve on the pipeline between the outlet of the deep bed denitrification filter and the inlet of the clean water tank is opened, and the deep bed denitrification The valve on the pipeline between the outlet of the filter tank and the inlet of the activated coke adsorption tank is closed, and the water obtained in step b directly enters the clear water tank through the pipeline and then is discharged;

Among them, the dosage of COD is comprehensively determined according to the detection results of the online nitrate nitrogen detector set at the inlet of the pre-filtration zone, the online COD detector set at the inlet of the main filter denitrification zone and the online nitrate nitrogen detector at the outlet;

Further, the gas-water backwashing of the pre-filtering area of the deep-bed denitrification filter tank, the main filter denitrification area and the activated coke adsorption tank is performed respectively according to the pressure difference change in each tank body, and the backwashing drainage of the main filter and denitrification area is performed. It can be discharged through the drain in this area and the pre-filtering area.

In the present invention, a pre-filtration zone is arranged on the upper part of the deep-bed denitrification filter, and the deep-bed denitrification filter is divided into a pre-filtration zone and a main filter and denitrification zone, so as to reduce the denitrification of the filter when the concentration of influent suspended solids fluctuates. Carbon source dosing points are set in both the pre-filtration area and the main filter and denitrification area, and the distribution ratio of carbon sources in the two areas is adjusted according to the turbidity of the influent water to ensure the efficient use of external carbon sources; As a supplementary unit, the coke adsorption tank avoids the problem of excessive COD in the system effluent caused by the addition of carbon sources during the unstable period of denitrification, improves the flexibility of adding carbon sources to the deep-bed denitrification filter, and strengthens the denitrification of the deep-bed filter. Nitrogen effect.

The above-mentioned embodiments are preferred embodiments of the present invention, not restrictive embodiments of the present invention. Any modifications or equivalent deformations made by those skilled in the art on the basis of the essential content of the present invention are all within the scope of the present invention. technical category.

Claims (10)

1. The utility model provides a system for realize reinforceing deep bed denitrification filtering pond denitrogenation which characterized in that: comprises a deep bed denitrification filter tank, an active coke adsorption tank and a clean water tank; the deep bed denitrification filter is divided into a pre-filtering area and a main filtering denitrification area, the outlet of the pre-filtering area is connected with the inlet of the main filtering denitrification area, the pre-filtering area is provided with a carbon source adding point, the inlet is provided with an online turbidity detector and a nitrate nitrogen detector, the main filtering denitrification area is provided with a carbon source adding point, the inlet and the outlet are respectively provided with an online COD detector, the water outlet is provided with an online nitrate nitrogen detector, and the water outlet of the active coke adsorption tank is provided with an online COD detector; the outlet of the deep bed denitrification filter tank is connected with the inlet of the active coke adsorption tank or directly connected with the inlet of the clean water tank, and the outlet of the active coke adsorption tank is connected with the inlet of the clean water tank.

2. The system for realizing the enhanced denitrification of the deep bed denitrification filter according to claim 1, is characterized in that: the empty bed volume ratio of the pre-filtering area and the main filtering denitrification area of the deep bed denitrification filter is 1: 4-1: 5.

3. The system for realizing the enhanced denitrification of the deep bed denitrification filter according to claim 1, is characterized in that: biological ceramsite is filled in a pre-filtering area of the deep bed denitrification filter, and the particle size of the biological ceramsite is 3-5 mm.

4. The system for realizing the enhanced denitrification of the deep bed denitrification filter according to claim 1, is characterized in that: the deep bed denitrification filter is characterized in that a three-way valve is arranged on a main filtering denitrification area water outlet pipe of the deep bed denitrification filter, two branch water outlet pipes which are divided into are respectively connected with an active coke adsorption tank inlet and a clean water tank inlet, and switch valves are arranged on the two branch water outlet pipes.

5. The system for realizing the enhanced denitrification of the deep bed denitrification filter according to claim 1, is characterized in that: the main filtration denitrification area of the deep bed denitrification filter takes quartz sand as a filter material, and the particle size is 1.5-3.5 mm.

6. The system for realizing the enhanced denitrification of the deep bed denitrification filter according to claim 1, is characterized in that: the filtering speed of the active coke adsorption tank is 8-10 m/h, and the height of the active coke adsorption tank is 2.0-2.5 m.

7. The system for realizing the enhanced denitrification of the deep bed denitrification filter according to claim 1, is characterized in that: the active coke filled in the active coke adsorption tank is coal granular active coke, the grain diameter is 4-10 mm, and the iodine value is more than or equal to 500 mg/g.

8. The system for realizing the enhanced denitrification of the deep bed denitrification filter according to claim 1, is characterized in that: and independent water backwashing systems are respectively arranged between the clean water tank and the pre-filtering area of the deep bed denitrification filter, between the clean water tank and the main filtration denitrification area of the deep bed denitrification filter and between the clean water tank and the active coke adsorption tank.

9. The system for realizing the enhanced denitrification of the deep bed denitrification filter according to claim 1, is characterized in that: and the pre-filtering area, the main filtering denitrification area and the active coke adsorption tank of the deep bed denitrification filter are respectively provided with an independent air washing system.

10. A method for implementing the system for enhancing the denitrification of the deep bed denitrification filter according to the claims 1-9, which is characterized in that: the method comprises the following steps:

a. the method comprises the following steps that water to be treated enters a pre-filtering area of a deep bed denitrification filter through a water inlet pipeline, passes through the pre-filtering area from top to bottom at a filtering speed of 5-8 m/h, is subjected to real-time detection of inlet water turbidity through an online turbidity detector, is added with a carbon source through a carbon source adding point, and is adjusted to be 0-20% according to the inlet water turbidity; when the inlet water turbidity is more than or equal to 8NTU, no carbon source is added in the region, and the effect of reducing the concentration of suspended matters entering the main filtration denitrification region is only exerted; when the inlet water turbidity is less than 8NTU, the suspended matter concentration of the area is reduced under the condition of adding a carbon source, and meanwhile, the microorganisms growing on the surface of the ceramsite also have denitrification effect;

b. b, enabling the effluent obtained in the step a to enter a deep bed filter main filtration denitrification area through a permeable partition wall, enabling the effluent to pass through the deep bed filter main filtration denitrification area from top to bottom at a filtration speed of 5-8 m/h, adding a carbon source through a carbon source adding point, enabling the carbon source adding proportion of the area to be 80-100%, denitrifying through the denitrification of microorganisms growing on the surfaces of quartz sand, and removing suspended matters through the interception adsorption of the quartz sand;

c. b, determining whether the active coke adsorption tank runs beyond the water outlet according to the COD concentration of the effluent, when the COD is higher than a target set value, closing a valve on a pipeline between the outlet of the deep bed denitrification filter tank and the inlet of the clean water tank, opening a valve on a pipeline between the outlet of the deep bed denitrification filter tank and the inlet of the active coke adsorption tank, enabling the effluent obtained in the step b to enter the active coke adsorption tank through the pipeline, and removing organic matters through the active coke adsorption tank from bottom to top at a filtering speed of 8-10 m/h to provide guarantee for the effluent reaching the COD during the initial denitrification function instability period of the denitrification start-up period and the low-temperature period;

when COD is lower than a target set value, a valve on a pipeline between the outlet of the deep bed denitrification filter and the inlet of the active coke adsorption tank is closed, a valve on a pipeline between the outlet of the deep bed denitrification filter and the inlet of the clean water tank is opened, and the active coke adsorption tank runs in an overrunning manner;

d. and c, the effluent obtained in the step c enters a clean water tank through an outlet and is discharged.

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