Post-denitrification operation method based on moving bed biofilm reactors (MBBRs)

Abstract

The invention discloses a post-denitrification device and operation method based on moving bed biofilm reactors (MBBRs), solving the problems in the existing MBBR denitrification process that filler is easy to calcify and precipitate, the concentration of a substrate at the rear section is low so as to limit the microorganism growth, and toxic and harmful matters are accumulated. The device is formed by connecting 2-4 MBBRs R1, R2, R3 and R4 in series. The effluent water of the secondary reactor is treated through anoxic denitrification, and nitrate nitrogen is degraded according to the volume of the unit reactors so as to determine adjustment of the stage time of the flowing sequence of influent water in the reactors. When the hardness in sewage is 120-300mg CaCO3 / L, the operation sequence is adjusted once nitrate nitrogen of 1.0-3.0kgN / m<3> is degraded; when the hardness in sewage is 300-480mg CaCO3 / L, the operation sequence is adjusted once nitrate nitrogen of 0.8-1.5kgN / m<3> is degraded; and when the hardness in sewage is greater than 480mg CaCO3 / L, the operation sequence is adjusted once nitrate nitrogen of 0.5-1.0kgN / m<3> is degraded. According to the invention, on the premise of high volume load, the effluent water TN can be still less than or equal to 10mg / L, the persistence is strong, and the stability is good.

Description

technical field

[0001] The invention belongs to the field of sewage denitrification and denitrification treatment, and in particular relates to a post-denitrification operation method based on MBBR. Background technique

[0002] In order to strengthen the protection of the water environment, the country has put forward higher requirements for the quality of effluent from sewage treatment plants, from Class B (TN<20mg / L) to Class A (TN<15mg / L), and then to some places Standard (TN<10mg / L), the next stage may be further restricted to TN<5mg / L. In the existing process system, the biochemical section often cannot achieve TN compliance, and subsequent advanced treatment is needed to meet higher water discharge requirements, especially for TN water discharge requirements.

[0003] Based on this demand, a large number of denitrification advanced treatment technologies have emerged, and the MBBR process is one of them. MBBR (MovingBedBiofilmReactor, moving bed biofilm ...

Examples

Embodiment 1

[0032] The winter secondary effluent of a certain urban sewage treatment plant is used as the influent water, with a water volume of 0.8m 3 / h, water temperature 10-14°C, average pH 6.90, nitrate nitrogen concentration in water 30-40mg / L, hardness 300-350mgCaCO 3 / L. Single reactor volume 1.44m 3 , a total of two reactors are arranged in series, which are respectively the first reactor R1 and the third reactor R3. The specific surface area of ​​the suspended filler used is 620m 2 / m 3 , the filling rate is 50%, and the specific gravity before filming is 0.95. Sodium acetate is added to the influent to supplement the carbon source required for denitrification.

[0033] When the operation started, the operation sequence was not adjusted, and the influent water flowed through the reactors R1 and R3 in sequence. 30 days after the operation started, the average load of the reactor R1 was 0.50kgN / (m 3 d), the average load of reactor R3 is 0.10kgN / (m 3d) The average TN concent...

Embodiment 2

[0035] The secondary effluent of a sewage treatment plant in summer is used as the influent, with a water volume of 1.2m 3 / h, water temperature 22-28°C, average pH 6.97, nitrate nitrogen concentration in water 60-65mg / L, hardness 300-350mgCaCO 3 / L. Single reactor volume 1.44m 3 , a total of three reactors are arranged in series, namely the first reactor R1, the second reactor R2, and the third reactor R3. The specific surface area of ​​the suspended filler used is 800m 2 / m 3 , the filling rate is 40%, the specific gravity before the film is 0.95, and sodium acetate is added to the influent water to supplement the carbon source required for denitrification;

[0036] At the beginning of operation, the order of water flow is R1, R2, R3. After 22 days of operation, the filler film is mature, and the beginning of 8 days is a cycle, and the order of operation is adjusted every cycle. The order of water flow in each cycle is R1. , R2, R3, R3, R1, R2, R2, R3, R1, and then rest...

technical field

[0001] The invention belongs to the field of sewage denitrification and denitrification treatment, and in particular relates to a post-denitrification operation method based on MBBR. Background technique

[0002] In order to strengthen the protection of the water environment, the country has put forward higher requirements for the quality of effluent from sewage treatment plants, from Class B (TN<20mg / L) to Class A (TN<15mg / L), and then to some places Standard (TN<10mg / L), the next stage may be further restricted to TN<5mg / L. In the existing process system, the biochemical section often cannot achieve TN compliance, and subsequent advanced treatment is needed to meet higher water discharge requirements, especially for TN water discharge requirements.

[0003] Based on this demand, a large number of denitrification advanced treatment technologies have emerged, and the MBBR process is one of them. MBBR (MovingBedBiofilmReactor, moving bed biofilm ...

Examples

Embodiment 1

[0032] The winter secondary effluent of a certain urban sewage treatment plant is used as the influent water, with a water volume of 0.8m 3 / h, water temperature 10-14°C, average pH 6.90, nitrate nitrogen concentration in water 30-40mg / L, hardness 300-350mgCaCO 3 / L. Single reactor volume 1.44m 3 , a total of two reactors are arranged in series, which are respectively the first reactor R1 and the third reactor R3. The specific surface area of ​​the suspended filler used is 620m 2 / m 3 , the filling rate is 50%, and the specific gravity before filming is 0.95. Sodium acetate is added to the influent to supplement the carbon source required for denitrification.

[0033] When the operation started, the operation sequence was not adjusted, and the influent water flowed through the reactors R1 and R3 in sequence. 30 days after the operation started, the average load of the reactor R1 was 0.50kgN / (m 3 d), the average load of reactor R3 is 0.10kgN / (m 3d) The average TN concent...

Embodiment 2

[0035] The secondary effluent of a sewage treatment plant in summer is used as the influent, with a water volume of 1.2m 3 / h, water temperature 22-28°C, average pH 6.97, nitrate nitrogen concentration in water 60-65mg / L, hardness 300-350mgCaCO 3 / L. Single reactor volume 1.44m 3 , a total of three reactors are arranged in series, namely the first reactor R1, the second reactor R2, and the third reactor R3. The specific surface area of ​​the suspended filler used is 800m 2 / m 3 , the filling rate is 40%, the specific gravity before the film is 0.95, and sodium acetate is added to the influent water to supplement the carbon source required for denitrification;

[0036] At the beginning of operation, the order of water flow is R1, R2, R3. After 22 days of operation, the filler film is mature, and the beginning of 8 days is a cycle, and the order of operation is adjusted every cycle. The order of water flow in each cycle is R1. , R2, R3, R3, R1, R2, R2, R3, R1, and then rest...

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