CN106145506A - The apparatus and method of coal chemical industrial waste water Anammox coupling heterotrophic denitrification denitrogenation - Google Patents

Abstract

"A device and method for anaerobic ammonium oxidation coupling heterotrophic denitrification of coal chemical wastewater" relates to a device and method for removing ammonia nitrogen in high-ammonia nitrogen coal chemical wastewater through stable and efficient anaerobic ammonium oxidation coupled heterotrophic denitrification, which belongs to In the technical field of biochemical sewage biological treatment, it is suitable for the treatment of coal chemical wastewater and other high-ammonia nitrogen organic industrial wastewater such as anaerobic digestion biogas slurry, aquaculture wastewater, and monosodium glutamate wastewater.

Description

Device and method for anaerobic ammonium oxidation coupling heterotrophic denitrification of coal chemical wastewater

technical field

The invention relates to a device and method for removing ammonia nitrogen in high-ammonia-nitrogen coal chemical wastewater through stable and efficient anaerobic ammonium oxidation coupling heterotrophic denitrification, which belongs to the technical field of biochemical sewage biological treatment, and is suitable for coal chemical wastewater and other such as anaerobic Digestive biogas slurry, aquaculture wastewater, monosodium glutamate wastewater and other high ammonia nitrogen organic industrial wastewater treatment.

Background technique

Coal chemical industry is the process of converting coal into gas, liquid, solid fuel and chemicals through chemical processing. The quality of coal chemical wastewater varies due to differences in production processes and equipment. It is a typical high ammonia nitrogen organic industrial wastewater. The COD concentration in the wastewater is about 1500-6000mg/l, and the ammonia nitrogen is 400-1500mg/l. The removal of ammonia nitrogen in coal chemical wastewater is the focus and difficulty of treatment.

The technology for treating this kind of high ammonia nitrogen and low C/N ratio wastewater is mainly divided into physical and chemical methods (stripping method and ammonia distillation method) and biochemical methods (whole process biological denitrification and short-range biological denitrification, anammox biological denitrification). Physicochemical deamination requires the addition of a large amount of chemicals, and the operating cost is high. If it is not properly treated and discharged directly into the atmosphere, the treated sewage will pollute the atmosphere, and the problem will not be solved fundamentally; if the ammonia recovery process is used, the final high ammonia nitrogen There are few engineering applications for the final disposal of the solution, and there is a risk of secondary pollution; the ammonia nitrogen in the physicochemical effluent cannot directly meet the standard, and has almost no removal effect on organic matter, and biological treatment is still required to remove organic matter and residual ammonia nitrogen. Biochemical method is recognized as an economical and efficient denitrification technology for high ammonia nitrogen wastewater, especially anammox biological denitrification represents the development direction of denitrification, and is a sustainable and environmentally friendly high ammonia nitrogen wastewater treatment technology.

The biological denitrification process converts ammonia nitrogen into nitrate nitrogen through nitrification, and then converts nitrate nitrogen into nitrogen gas from the water through denitrification. In the nitrification stage, the conversion of ammonia nitrogen into nitrate is two different reactions completed by two independent types of bacteria. First, ammonia nitrogen is converted into nitrite (NO ₂ -N) by Nitrosomonas, and then by nitrifying bacteria (Nitrobacter) converts nitrite to nitrate (NO ₃ -N). The final product of nitrification in traditional biological denitrification process is nitrate, and denitrification uses NO ₃ -N as electron acceptor.

Anammox (Anammox) is a new type of biological denitrification technology developed by the Biotechnology Laboratory of Delft University of Technology in the Netherlands in the mid-1990s. It refers to the direct conversion of NO ₂ -N As the electron acceptor, NH ₄ ⁺ -N is used as the electron donor to convert two kinds of nitrogen into nitrogen at the same time. The energy generated by this process can enable anammox bacteria to survive under anoxic conditions. Anammox technology is the most economical biological denitrification technology known at present. Compared with traditional nitrification and denitrification, anaerobic ammonium oxidation does not require additional organic matter as electron donors, which not only saves costs, but also prevents secondary pollution; compared with traditional nitrification and denitrification, oxygen consumption is reduced by 62.5%, and denitrification does not require organic carbon sources. It is especially suitable for the treatment of wastewater with low carbon-to-nitrogen ratio and high ammonia-nitrogen.

Anammox technology has been applied in the treatment of high-ammonia-nitrogen wastewater such as fermentation biogas slurry, landfill leachate, and monosodium glutamate wastewater, but it is rarely used in the treatment of coal chemical wastewater. "A device and method for anaerobic ammonium oxidation coupled with heterotrophic denitrification biological denitrification of coal chemical wastewater" provides a cost-effective new technology for denitrification of coal chemical wastewater.

Contents of the invention

The purpose of the present invention is to propose a device and method for treating coal chemical industry wastewater through anaerobic ammonium oxidation coupling heterotrophic denitrification biological denitrification.

A treatment device for anaerobic ammonium oxidation coupled with heterotrophic denitrification biological denitrification of high-ammonia nitrogen coal chemical wastewater, which is characterized in that it is equipped with a pre-heterotrophic denitrification tank (1), an integrated anammox tank (2), a sedimentation Pond (3), outlet pool (4).

The pre-heterotrophic denitrification tank is a cylindrical anaerobic reactor with a water distributor (1.3) at the bottom, the raw water pipe (1.1) and the water distributor (1.3) are connected, and two packing brackets (1.4) are arranged at the middle and upper part , the ethylene-propylene copolymer plate packing (1.14) is installed between the packing brackets, the packing distance is 8cm, the upper part is equipped with a three-phase separator (1.6), and the gas collection chamber (1.7) of the three-phase separator is connected with the exhaust pipe (1.9). After the outlet water of the heterotrophic denitrification tank is connected to the system outlet return pipe (1.15) through the circulation pump (1.2) and the circulation pipe (1.12), it returns to the pre-heterotrophic denitrification tank through the water distributor (1.3), and the supernatant After being collected by the outlet tank (1.8), it flows out of the pre-heterotrophic denitrification tank through the outlet pipe (1.10). The inner wall of the pre-heterotrophic denitrification tank is provided with a baffle (1.13), and the lower part is provided with an inlet (1.5) and a sampling valve ( 1.11);

The integrated anaerobic ammonium oxidation tank is a plug-flow reactor, and the effluent of the pre-heterotrophic denitrification tank passes through the outlet pipe (1.10) of the pre-heterotrophic denitrification tank and the sludge return pipe (1.10) of the integrated anaerobic ammonium oxidation tank ( 2.7) After connecting, enter the integrated anammox tank, the bottom of the integrated anammox tank is equipped with a microporous rubber membrane aeration head (2.4), and the Roots blower (2.6) passes through the air pipe (2.8) and the aeration The head (2.4) is connected, and the integrated anaerobic ammonium oxidation tank is filled with polyurethane sponge suspension filler (2.1). 2.2), and at the same time a pH online measuring instrument (2.3) is set at the end.

The inclined plate filler (3.1) is set in the sedimentation tank, and the sludge at the bottom of the sedimentation tank enters the head end of the integrated anaerobic ammonium oxidation tank through the sludge return pump (2.5) of the integrated anaerobic ammonium oxidation tank, and the supernatant of the sedimentation tank into the effluent pool;

The system outlet pipe (4.1) is installed on the upper part of the outlet pool, and the system outlet water return pump (4.2) is installed at the bottom. The system outlet water return pump is connected to the raw water pipe (1.1) of the pre-heterotrophic denitrification tank through the system outlet water return pipe (1.15).

The present invention also provides a method for treating high-ammonia-nitrogen coal chemical wastewater by using the above-mentioned device through anaerobic ammonium oxidation coupling heterotrophic denitrification biological denitrification, which is characterized in that it comprises the following steps:

1) The anaerobic granular sludge obtained from the activated sludge in the aeration tank of the coal chemical wastewater treatment plant and the UASB reactor of the starch wastewater treatment plant was added to the pre-heterotrophic denitrification tank according to the mass ratio of 1:1, and inoculated The final sludge concentration MLSS is about 16000mg/l; add the nitrification sludge from the urban sewage plant with good activity to the integrated anaerobic ammonium oxidation tank, and the sludge concentration MLSS after adding is about 7000mg/l; at the same time, the polyurethane The sponge biological filler is filled into the integrated anaerobic ammonia oxidation tank, and the filling rate is 25-30% of the effective tank capacity;

2) The pretreated coal chemical wastewater is mixed with the system effluent and then enters the pre-heterotrophic denitrification tank. The operating temperature of the pre-heterotrophic denitrification tank is 28-31 °C, the operating pH value is 7.5-8.3, and the hydraulic retention time is HRT. 20-36 hours, HRT prolongs with the increase of the COD concentration of organic matter in coal chemical wastewater and the concentration of nitrate nitrogen NO ₃ ^- -N in the effluent water;

3) The effluent from the pre-heterotrophic denitrification tank enters the integrated anammox tank. The hydraulic retention time HRT of the integrated anammox tank is 36-48 hours, the operating temperature is 25-30°C, and the operating pH is 7.1-8.3, the dissolved oxygen DO is maintained at 0.2-0.5mg/L by adjusting the aeration rate, and the sludge return ratio is maintained at 40%-100%.

4) The mixed liquid in the integrated anaerobic ammonium oxidation tank flows into the outlet pool after being separated from the mud and water in the sedimentation tank, and the final treated water of the system flows out through the outlet pipe. The reflux ratio of the system outlet water is 100-400%. With the improvement of the denitrification efficiency of the oxidation pond, the effluent reflux ratio of the system is gradually reduced from about 400% to about 100%.

Technical principle: The pretreated coal chemical wastewater and the return system effluent enter the pre-heterotrophic denitrification tank at the same time, and the denitrifying bacteria in the pool use the organic matter in the raw water to complete the combined nitrogen (NO ₂ ^- -N or NO ₃ ^- -N) efficient denitrification to achieve biological denitrification and recovery of alkalinity. At the same time, the remaining organic COD from denitrification is further removed through the synergistic effect of hydrolytic acidification bacteria and methanogens, creating favorable conditions for subsequent anammox autotrophic denitrification.

The effluent from the pre-heterotrophic denitrification tank enters the integrated anaerobic ammonium oxidation tank, and the dissolved oxygen DO concentration is controlled to be <0.5mg/l. The ammonia oxidizing bacteria AOB in the suspended sludge and the anaerobic ammonium oxidizing bacteria AnAOB on the suspended packing Synergistically, ammonia nitrogen nitrosation and anaerobic ammonium oxidation are completed simultaneously to achieve deep denitrification. After the mixed liquid in the autotrophic biological denitrification tank enters the sedimentation tank for separation of mud and water, it finally flows into the overflow water of the effluent tank to complete the efficient and deep removal of organic matter and nitrogen in coal chemical wastewater.

In the above-mentioned coal chemical wastewater biological treatment system, the organic matter in the wastewater is mainly used for denitrification and methane production to reduce _CO2 emissions. In the integrated anammox tank, the nitrification and anammox of high-concentration ammonia nitrogen can be completed in one step, saving more than 50% of the aeration rate and 90% of the denitrification carbon source, and reducing the remaining sludge production of the entire system More than 60%.

Compared with the prior art, the coal chemical industry wastewater treatment method involving anaerobic ammonium oxidation coupling heterotrophic denitrification biological denitrification has the following advantages:

1) In the pre-heterotrophic denitrification tank, the granulated and enriched heterotrophic denitrification bacteria use the organic matter COD in the raw water to reduce the NO ₃ -N or NO ₂ -N in the effluent water of the system to nitrogen, and simultaneously realize COD Removal of total nitrogen and TN, reducing the addition of external carbon sources, and recovering alkalinity; the remaining COD after denitrification is removed through anaerobic particle methane production. The traditional process uses aerobic aerobic degradation of organic matter, "consuming energy", and at the same time produces a large amount of residual biological sludge that is difficult to handle, and emits a large amount of CO ₂ .

2) The heterotrophic denitrification reactor is a columnar reactor, the functional microorganisms exist in the form of particles, the removal load is high, and the intermediate sedimentation tank and sludge return system are omitted.

3) The effluent from the heterotrophic denitrification tank has become high ammonia nitrogen and low C/N wastewater, which is very suitable for anaerobic ammonium oxidation denitrification. In the integrated anammox tank, through the combination of nitrifying bacteria and anammox bacteria, high-efficiency and low-consumption removal of nitrogen in coal chemical wastewater can be realized. Compared with traditional processes, more than 50% of aeration and 90% can be saved % denitrification carbon source, the remaining sludge production of the whole system is reduced by more than 60%. .

4) While realizing the standard discharge and recycling of coal chemical wastewater, this technology embodies the concept of sustainable biological treatment of coal chemical wastewater with minimum COD oxidation, minimum _CO2 emission, minimum residual sludge generation, and maximum energy recovery.

Description of drawings

Figure 1 is a schematic structural view of the device of the present invention.

detailed description

The present invention will be further described below in conjunction with accompanying drawing and embodiment: Embodiment 1:

High ammonia nitrogen coal chemical wastewater anaerobic ammonium oxidation coupling heterotrophic denitrification biological denitrification treatment device: There are pre-heterotrophic denitrification tank 1, integrated anaerobic ammonium oxidation tank 2, sedimentation tank 3, and effluent tank 4.

The pre-heterotrophic denitrification tank is a cylindrical anaerobic reactor, with a water distributor 1.3 at the bottom, a raw water pipe 1.1 connected to the water distributor 1.3, and two packing brackets 1.4 at the middle and upper parts, and ethylene-propylene oxide is installed between the packing brackets Copolymerized plate packing 1.14, packing spacing 100cm, three-phase separator 1.6 is arranged on the upper part, the gas collection chamber 1.7 of the three-phase separator is connected to the exhaust pipe 1.9, and the effluent of the pre-heterotrophic denitrification tank passes through the circulating pump 1.2, the circulating pipe 1.12 and the After the system outlet and return pipe 1.15 is connected, it flows back to the pre-heterotrophic denitrification tank through the water distributor 1.3. A baffle 1.13 is set on the inner wall of the nitrification tank, and an inlet 1.5 and a sampling valve 1.11 are set at the lower part;

The integrated anaerobic ammonium oxidation tank is a cuboid reactor, and the effluent of the pre-heterotrophic denitrification tank is connected to the sludge return pipe 2.7 of the integrated anaerobic ammonium oxidation tank through the outlet pipe 1.10 of the pre-heterotrophic denitrification tank , enter the integrated anammox tank, the bottom of the integrated anammox tank is equipped with a microporous rubber diaphragm aeration head 2.4, the Roots blower 2.6 is connected to the aerator head 2.4 through the air pipe 2.8, and the integrated anammox The pool is filled with polyurethane sponge suspension filler 2.1, and the size of a single filler is 1.0×1.0×1.0cm. Dissolved oxygen DO online analyzer 2.2 is installed at the front and rear sections of the pool respectively, and pH online analyzer 2.3 is installed at the end.

The inclined plate filler 3.1 is set in the sedimentation tank, the sludge at the bottom of the sedimentation tank enters the head end of the integrated anaerobic ammonium oxidation tank through the sludge return pump 2.5 of the integrated anammox tank, and the supernatant of the sedimentation tank enters the effluent tank ;

The system outlet pipe 4.1 is arranged on the upper part of the outlet pool, and the system outlet return pump 4.2 is arranged at the bottom, and the system outlet return pump is connected to the raw water pipe 1.1 of the pre-heterotrophic denitrification tank through the system outlet return pipe 1.15.

Embodiment 2: the operating method of utilizing the above-mentioned device of the present invention:

The experimental water is taken from the effluent of a coal chemical wastewater treatment plant in Tuoketuo County, Inner Mongolia Autonomous Region. It is a typical high ammonia nitrogen coal chemical wastewater. The water quality is as follows: COD 800~1900mg/l; NH ₄ ⁺ -N 1300~1500mg/l; SS 300~700mg/l; alkalinity 2500~4000mg/l; pH 6.5~7.8. The test system is shown in Figure 1, which consists of a pre-heterotrophic denitrification tank, an integrated anammox tank, a sedimentation tank, and an outlet tank.

The specific operation process is as follows:

1) The anaerobic granular sludge taken from the activated sludge in the aeration tank of the coal chemical wastewater treatment plant and the UASB reactor of the starch wastewater treatment plant was added to the pre-heterotrophic denitrification tank according to the mass ratio of 1:1, and inoculated The final sludge concentration MLSS is about 13000mg/l; add the nitrification sludge from the urban sewage plant with good activity to the integrated anaerobic ammonium oxidation tank, and the sludge concentration MLSS after adding is about 6000mg/l; at the same time, the polyurethane The sponge biological filler is filled into the integrated anaerobic ammonia oxidation tank, and the filling rate is 27% of the effective tank capacity;

2) The pretreated coal chemical wastewater is mixed with the system effluent and then enters the pre-heterotrophic denitrification tank. The operating temperature of the pre-heterotrophic denitrification tank is 28-31°C, the operating pH value is 7.3-8.1, and the hydraulic retention time is HRT. 22 hours, HRT prolongs with the increase of COD concentration of organic matter in coal chemical wastewater and nitrate nitrogen NO ₃ ^- -N concentration in effluent water;

3) The effluent from the pre-heterotrophic denitrification tank enters the integrated anammox tank. The hydraulic retention time HRT of the integrated anammox tank is 48 hours, the operating temperature is 25-30°C, and the operating pH value is 7.1- 8.3. The dissolved oxygen DO is maintained at 0.2-0.5mg/L by adjusting the aeration rate, and the sludge return ratio is maintained at 40%-100%.

4) The mixed liquid in the integrated anaerobic ammonium oxidation tank flows into the outlet pool after being separated from the mud and water in the sedimentation tank, and the final treated water of the system flows out through the outlet pipe. The reflux ratio of the system outlet water is 100-300%. With the improvement of the denitrification efficiency of the oxidation pond, the effluent reflux ratio of the system is gradually reduced from about 300% to about 100%.

Continuous test results show that: effluent COD concentration < 300mg/l, COD removal rate higher than 75%, effluent TN < 100mg/l, NH ₄ ⁺ -N < 35mg/l, autotrophic biological denitrification pool TN removal load is 0.40Kg /m ³ ·d. Under the premise of reducing energy consumption, reducing CO ₂ and excess sludge emissions, the system effluent water quality meets the national discharge standard for coal chemical wastewater, and this technology is a sustainable sewage treatment technology.

Claims (2)

1. A treatment device for anaerobic ammonium oxidation coupling heterotrophic denitrification biological denitrification of coal chemical industry wastewater, characterized in that it is equipped with a pre-heterotrophic denitrification tank (1) and an integrated anammox tank (2) , settling tank (3), outlet pool (4). The pre-heterotrophic denitrification tank is a cylindrical anaerobic reactor with a water distributor (1.3) at the bottom, the raw water pipe (1.1) and the water distributor (1.3) are connected, and two packing brackets (1.4) are installed at the middle and upper part , the ethylene-propylene copolymer plate packing (1.14) is installed between the packing brackets, the packing distance is 8cm, the upper part is equipped with a three-phase separator (1.6), and the gas collection chamber (1.7) of the three-phase separator is connected with the exhaust pipe (1.9). After the outlet water of the heterotrophic denitrification tank is connected to the system outlet return pipe (1.15) through the circulation pump (1.2) and the circulation pipe (1.12), it returns to the pre-heterotrophic denitrification tank through the water distributor (1.3), and the supernatant After being collected by the outlet tank (1.8), it flows out of the pre-heterotrophic denitrification tank through the outlet pipe (1.10). The inner wall of the pre-heterotrophic denitrification tank is provided with a baffle (1.13), and the lower part is provided with an inlet (1.5) and a sampling valve ( 1.11); The integrated anaerobic ammonium oxidation tank is a plug-flow reactor, and the effluent of the pre-heterotrophic denitrification tank passes through the outlet pipe (1.10) of the pre-heterotrophic denitrification tank and the sludge return pipe (1.10) of the integrated anaerobic ammonium oxidation tank ( 2.7) After connecting, enter the integrated anammox tank, the bottom of the integrated anammox tank is equipped with a microporous rubber membrane aeration head (2.4), and the Roots blower (2.6) passes through the air pipe (2.8) and the aeration The head (2.4) is connected, and the integrated anaerobic ammonium oxidation tank is filled with polyurethane sponge suspension filler (2.1). 2.2), and at the same time a pH online measuring instrument (2.3) is set at the end. The inclined plate filler (3.1) is set in the sedimentation tank, and the sludge at the bottom of the sedimentation tank enters the head end of the integrated anaerobic ammonium oxidation tank through the sludge return pump (2.5) of the integrated anaerobic ammonium oxidation tank, and the supernatant of the sedimentation tank into the effluent pool; The system outlet pipe (4.1) is installed on the upper part of the outlet pool, and the system outlet water return pump (4.2) is installed at the bottom. The system outlet water return pump is connected to the raw water pipe (1.1) of the pre-heterotrophic denitrification tank through the system outlet water return pipe (1.15). 2. A method for treating high-ammonia nitrogen coal chemical wastewater by anaerobic ammonium oxidation coupling heterotrophic denitrification biological denitrification using the above-mentioned device, which is characterized in that it comprises the following steps: 1) The anaerobic granular sludge obtained from the activated sludge in the aeration tank of the coal chemical wastewater treatment plant and the UASB reactor of the starch wastewater treatment plant was added to the pre-heterotrophic denitrification tank according to the mass ratio of 1:1, and inoculated The final sludge concentration MLSS is about 16000mg/l; add the nitrification sludge from the urban sewage plant with good activity to the integrated anaerobic ammonium oxidation tank, and the sludge concentration MLSS after adding is about 7000mg/l; at the same time, the polyurethane The sponge biological filler is filled into the integrated anaerobic ammonia oxidation tank, and the filling rate is 25-30% of the effective tank capacity; 2) The pretreated coal chemical wastewater is mixed with the system effluent and then enters the pre-heterotrophic denitrification tank. The operating temperature of the pre-heterotrophic denitrification tank is 28-31 °C, the operating pH value is 7.5-8.3, and the hydraulic retention time is HRT. 20-36 hours, HRT prolongs with the increase of the COD concentration of organic matter in coal chemical wastewater and the concentration of nitrate nitrogen NO ₃ ^- -N in the effluent water; 3) The effluent from the pre-heterotrophic denitrification tank enters the integrated anammox tank. The hydraulic retention time HRT of the integrated anammox tank is 36-48 hours, the operating temperature is 25-30°C, and the operating pH is 7.1-8.3, the dissolved oxygen DO is maintained at 0.2-0.5mg/L by adjusting the aeration rate, and the sludge return ratio is maintained at 40%-100%. 4) The mixed liquid in the integrated anaerobic ammonium oxidation tank flows into the outlet pool after being separated from the mud and water in the sedimentation tank, and the final treated water of the system flows out through the outlet pipe. The reflux ratio of the system outlet water is 100-400%. With the improvement of the denitrification efficiency of the oxidation pond, the effluent reflux ratio of the system is gradually reduced from about 400% to about 100%.