Petrochemical wastewater treatment system

Abstract

The invention discloses a petroleum and petrochemical wastewater treatment system, which relates to the technical field of wastewater treatment and comprises an exclusive strain in-situ production device, a compact sludge separation device and a strain sludge loading device, a plurality of sludge cyclone pipes are arranged in the dense sludge separation device, and a sludge inlet, a light sludge outlet and a dense sludge outlet are formed in the dense sludge separation device; the strain sludge loading device is provided with an inlet and an outlet, and the inlet is respectively connected with a strain outlet and a compact sludge outlet of the exclusive strain in-situ production device through a strain conveying pipeline and a compact sludge conveying pipeline; and the system is arranged between sludge return pipes of the sedimentation tank and the biochemical tank. According to the invention, continuous propagation supply is carried out on domesticated specific exclusive strains, full agglomeration and mixing of the domesticated specific exclusive strains and dense sludge subjected to cyclone separation are ensured, the survival rate of the strains is ensured, and the degradation efficiency of pollutants is enhanced. Meanwhile, the improvement of sludge granularity and the enhancement of activity are promoted, the biological stability of microorganisms in a biochemical pool is enhanced, a mutualistic symbiotic virtuous cycle is formed, and the wastewater treatment efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of wastewater treatment, and in particular to a petroleum and petrochemical wastewater treatment system. Background Art

[0002] In the process of petroleum and petrochemical production, a large amount of wastewater is generated, which usually contains complex organic and inorganic pollutants, including phenols, nitriles, amines and many other toxic and hazardous substances. These pollutants are not only in high concentration, but also have significant biological toxicity, posing a serious threat to the ecological environment and human health. Therefore, it is particularly important to develop efficient and stable petroleum and petrochemical wastewater treatment systems and methods.

[0003] In the biological treatment stage, the traditional petroleum and petrochemical wastewater treatment process mainly relies on the pretreatment unit to remove suspended solids and some difficult-to-degrade organic matter in the wastewater, and then degrades the organic matter through the microbial community in the anaerobic / anoxic tank and the aerobic tank. The anaerobic / anoxic tank mainly converts organic matter into small molecules such as methane and carbon dioxide through the action of anaerobic bacteria, while the aerobic tank uses aerobic bacteria to further degrade organic matter to achieve wastewater purification. However, since toxic substances such as phenols, nitriles, and amines in petroleum and petrochemical wastewater have a significant inhibitory effect on the growth and reproduction of microorganisms, and may even cause the death of microorganisms, thereby reducing the stability and treatment efficiency of the biological treatment system, the traditional biological treatment process faces many challenges in practical applications. Summary of the invention

[0004] Aiming at the technical problems of poor stability and treatment efficiency of microorganisms in biochemical pools for treating specific harmful organic substances in petroleum and petrochemical wastewater in the prior art, the present invention proposes a petroleum and petrochemical wastewater treatment system.

[0005] A petroleum and petrochemical wastewater treatment system, characterized in that the treatment system comprises an exclusive strain in-situ production device, a dense sludge separation device and a strain sludge loading device;

[0006] The dense sludge separation device is provided with a sludge inlet, a light sludge outlet and a dense sludge outlet on its surface, and a plurality of sludge cyclone tubes are arranged inside, and the sludge cyclone tubes are connected by internal pipelines and communicate with the sludge inlet, the light sludge outlet and the dense sludge outlet;

[0007] The bacterial strain sludge loading device is provided with a bacterial strain sludge loading device inlet and a bacterial strain sludge loading device outlet; the bacterial strain sludge loading device inlet is connected to the bacterial strain outlet and the dense sludge outlet arranged at the bottom of the exclusive bacterial strain in-situ production device through a bacterial strain delivery pipeline and a dense sludge delivery pipeline respectively;

[0008] The treatment system is arranged between the sludge return pipes of the sedimentation tank and the biochemical tank of the sewage treatment plant, the sludge inlet is connected to the sludge return pipe of the sedimentation tank, and the strain sludge loading device outlet is connected to the biochemical tank through a pipeline.

[0009] Furthermore, the sludge cyclone is conical, including a cylindrical section and a conical section. The sludge cyclone is provided with an inlet, an overflow port and an underflow port respectively, which are connected to the sludge inlet, the light sludge outlet and the dense sludge outlet.

[0010] Furthermore, the light sludge outlet is arranged at the top, and the dense sludge outlet is arranged at the bottom.

[0011] Furthermore, the number of the sludge cyclone tubes is 4.

[0012] Furthermore, the bacterial sludge loading device is composed of a hollow circular tube, and the circular tube is an internally threaded tube.

[0013] Furthermore, the bacterial strain sludge loading device is fixed by a fixing frame.

[0014] Furthermore, the dedicated bacterial strain in-situ production device is used to expand the cultivation of dedicated bacterial strains that specifically treat specific harmful organic substances in petroleum and petrochemical wastewater.

[0015] Furthermore, the exclusive bacterial strain is a microorganism that is isolated, screened, acclimated with raw water, and then biologically expanded.

[0016] Furthermore, the exclusive strain in-situ production device is provided with temperature, pressure and dissolved oxygen control devices.

[0017] Furthermore, a water bath jacket layer is provided outside the inner hollow circular tube of the bacterial strain conveying pipeline and the bacterial strain sludge loading device.

[0018] The present invention has the following beneficial effects:

[0019] 1. The petroleum and petrochemical wastewater treatment system proposed in the present invention realizes the continuous expansion and preservation of specific exclusive bacteria species that have been domesticated with raw water by integrating an exclusive bacteria species in situ production device, ensuring that sufficient and adaptable exclusive bacteria species are fully mixed with the dense sludge obtained after sludge cyclone separation and transported to the biochemical pool, which not only strengthens the stability of the microbial ecology, but also significantly enhances the ability of microorganisms in the biochemical pool to degrade pollutants, thereby improving the efficiency and quality of wastewater treatment.

[0020] 2. On the infrastructure of the existing sewage treatment plant, the petroleum and petrochemical wastewater treatment system proposed by the present invention is installed between the return pipes of the sedimentation tank and the biochemical tank. There is no need to carry out large-scale structural transformation or layout adjustment of the sewage treatment plant. It can not only control the investment cost, but also realize the efficient utilization of resources, and has good technical, economic and environmental benefits.

[0021] 3. The present invention introduces dense sludge separation technology to effectively remove light components from the sludge returning from the sedimentation tank to the biochemical tank, and only retains dense sludge with a compact structure, high degree of granulation, and strong microbial activity for return, which significantly improves the system stability of the biochemical tank, reduces the impact of sludge load fluctuations on the biochemical treatment process, and ensures the continuous and stable operation of the wastewater treatment system.

[0022] 4. The unique structural characteristics of the dense sludge obtained during the cyclone separation process provide an ideal attachment environment for the exclusive bacteria, effectively increasing the load of the bacteria. These dense sludges loaded with exclusive bacteria are dispersed in the biochemical pool as active carriers, which not only ensures the survival rate of the bacteria, but also enhances the degradation efficiency of specific pollutants. At the same time, the full agglomeration and mixing of the exclusive bacteria and dense sludge further promotes the improvement of sludge particle size and activity, forming a virtuous cycle of mutual symbiosis and significantly improving the comprehensive efficiency of wastewater treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0024] Figure 1 The present invention discloses a petroleum and petrochemical wastewater treatment system structure and material flow diagram.

[0025] Figure 2 The COD concentration data of sewage treated in Example 1 and Comparative Example 1 of the present invention are statistical graphs.

[0026] Figure 3 The COD concentration data of sewage treated in Example 2 of the present invention and Comparative Example 2 are statistical graphs.

[0027] In the figure: 1. Exclusive strain in-situ production device; 2. Strain delivery pipeline; 3. Dense sludge delivery pipeline; 4. Sludge cyclone tube; 5. Dense sludge separation device; 6. Strain sludge loading device; 7. Fixed frame; 8. Strain outlet; 9. Strain sludge loading device outlet; 10. Strain sludge loading device inlet; 11. Sludge inlet; 12. Light sludge outlet; 13. Dense sludge outlet. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] like Figure 1 A petroleum and petrochemical wastewater treatment system is shown, characterized in that the treatment system includes an exclusive strain in-situ production device 1, a dense sludge separation device 5 and a strain sludge loading device 6, the sludge inlet 11 is connected to the sludge return pipeline of the sewage treatment plant sedimentation tank, the sludge return pipeline is provided with a flow meter and a one-way valve, and the sludge flows from the sewage treatment sedimentation tank to the sludge inlet 11.

[0030] The exclusive strain in-situ production device 1 is used for the in-situ production of exclusive strains. The exclusive strains refer to the exclusive strains that are separated and screened and applied to harmful organic matter in petroleum and petrochemical wastewater. They must first be tamed in raw water and then biologically expanded. One or more domesticated exclusive strains can be expanded in the exclusive strain in-situ production device 1. The exclusive strain in-situ production device 1 is provided with a precise control device for temperature, pressure and dissolved oxygen to achieve continuous expansion and preservation of the specific exclusive strains, and meet the production requirements of exclusive strains for sewage treatment.

[0031] The dense sludge separation device 5 is a cavity structure, and a sludge inlet 11, a light sludge outlet 12 and a dense sludge outlet 13 are respectively arranged on its surface. The light sludge outlet 12 is arranged at the top, and the dense sludge outlet 13 is arranged at the bottom. A plurality of sludge cyclone tubes 4 are arranged inside the dense sludge separation device 5. The sludge cyclone tubes 4 are connected by internal pipelines to the sludge inlet 11, the light sludge outlet 12 and the dense sludge outlet 13. Different outlets realize the cyclone separation of light sludge and dense sludge. The sludge cyclone tube 4 is conical, including a cylindrical section and a conical section. The sludge cyclone tube 4 is respectively provided with an inlet, an overflow port and an underflow port, which are connected to the sludge inlet 11, the light sludge outlet 12 and the dense sludge outlet 13; the number of the sludge cyclone tubes 4 is 4, and each sludge cyclone tube 4 is connected by an independent branch pipeline. These independent branch pipelines ensure that each sludge cyclone tube 4 can work efficiently and transport the separated sludge to the corresponding outlets for treatment.

[0032] The bacterial strain sludge loading device 6 is provided with a bacterial strain sludge loading device inlet 10 and a bacterial strain sludge loading device outlet 9 according to the material flow direction; the bacterial strain sludge loading device 6 is composed of a hollow circular tube, and the circular tube is an internally threaded tube. Such a design can increase the turbulence of the fluid and promote the mixing of the bacterial liquid and the sludge; the circular tube of the bacterial strain sludge loading device 6 is provided with a water bath jacket layer on the outside, which can control the temperature of the pipeline body, and the bacterial strain sludge loading device 6 is fixed by a fixing frame 7. The bacterial strain sludge loading device 6 is also equipped with an advanced control system, which can monitor and control the temperature of the bacterial strain sludge loading device in real time, thereby expanding the applicable temperature range of the bacterial strain sludge loading device, so that it can operate stably under different temperature conditions.

[0033] The two ends of the strain delivery pipeline 2 are respectively connected to the strain outlet 8 and the strain sludge loading device inlet 6 arranged at the bottom of the dedicated strain in-situ production device 1. A one-way valve is arranged on the strain delivery pipeline 2, and the material flows from the dedicated strain in-situ production device 1 to the strain sludge loading device 6.

[0034] The two ends of the dense sludge conveying pipeline 3 are respectively connected to the dense sludge outlet 13 and the bacterial sludge loading device inlet 10, and a one-way valve is arranged on the dense sludge conveying pipeline 3, and the material flows from the dense sludge separation device 5 to the bacterial sludge loading device 6;

[0035] The treatment system is arranged between the sedimentation tank and the biochemical tank of the sewage treatment plant, the sludge inlet 11 is connected to the sludge return pipe of the sedimentation tank, and the bacterial sludge loading device outlet 9 is connected to the biochemical tank through a pipeline.

[0036] In the bacterial sludge loading device 6, the dedicated bacterial liquid and the dense sludge can be fully combined under specific conditions. This combination is achieved through agglomeration and the special structure inside the loading device. The dense sludge loaded with the dedicated bacteria will flow back to the biochemical pool through the pipeline again, providing strong support for the biological treatment process in the biochemical pool.

[0037] The return line of the sedimentation tank is connected to the sludge inlet 11. A flow meter and a one-way valve are provided on the delivery line. The flow meter can accurately measure the flow rate of the sludge, and the one-way valve can control the flow direction of the sludge to ensure that the sludge flows in a predetermined direction. By adjusting the flow meter and the one-way valve, the flow rate of the sludge can be adjusted to adapt to the processing flow rate of the dense sludge separation device 5, thereby ensuring the normal operation of the dense sludge separation device 5.

[0038] Working principle:

[0039] The petroleum and petrochemical wastewater treatment system disclosed in the present invention is arranged between the sedimentation tank and the sludge return pipe of the biochemical tank of the sewage treatment plant. The sludge in the sewage treatment sedimentation tank passes through the sludge return pipe, is treated in the dense sludge separation device 5, enters the sludge cyclone tube 4 from the sludge inlet 11, and is separated into light sludge and dense sludge. The light sludge flows out through the light sludge outlet 12 for further treatment; the dense sludge is transported to the bacterial sludge loading device 6 by the dense sludge conveying pipeline 3 through the dense sludge outlet 13;

[0040] At the same time, the specific exclusive bacteria strains acclimated with raw water are continuously expanded and preserved through the exclusive bacteria strain in-situ production device 1 to obtain a large amount of exclusive bacteria liquid, which is continuously introduced into the bacteria strain sludge loading device 6 through the bacteria strain transport pipeline 2;

[0041] The dense sludge and the dedicated bacteria are fully mixed through agglomeration in the bacteria sludge loading device 6, and are discharged through the outlet 9 of the bacteria sludge loading device and returned to the biochemical pool of the sewage treatment plant, providing strong support for the biological treatment process in the biochemical pool.

[0042] Embodiment 1:

[0043] In a large petroleum and petrochemical wastewater treatment plant, the traditional petroleum and petrochemical wastewater biological treatment process was used in the experiment, which mainly includes pretreatment, biochemical tank treatment and sedimentation tank sedimentation. In order to further improve the treatment effect, we added the petroleum and petrochemical wastewater treatment system provided by the present invention to the sludge return pipe between the sedimentation tank and the biochemical tank.

[0044] In view of the stable water quality and water volume of the sewage treatment plant, COD (chemical oxygen demand) was selected as the main indicator for evaluating the sewage treatment effect. After installing and stably operating the sewage treatment system provided by the present invention, we recorded the COD concentration changes of the inlet and outlet water for 14 consecutive days, and took samples for testing every 48 hours.

[0045] Comparative Example 1:

[0046] This comparative example was conducted in the same sewage treatment plant as Example 1, but the only difference was that the test was conducted in a conventional operation mode before the sewage treatment system provided by the present invention was installed. The COD inlet and outlet concentrations were also monitored for 14 days to evaluate the sewage treatment effect.

[0047] Example 2

[0048] The petroleum and petrochemical wastewater treatment plant tested in this embodiment has a daily treatment scale of about 7,500 cubic meters and mainly relies on the traditional petroleum and petrochemical wastewater biological treatment process, which covers key sewage treatment facilities such as biochemical tanks and sedimentation tanks. The sewage treatment plant is equipped with two independent biological treatment process lines, which can be simply understood as having two complete biochemical tank facilities, A and B. In order to verify the effectiveness of the present invention, we specially installed the petroleum and petrochemical wastewater treatment system provided by the present invention on the sludge return pipeline between the sedimentation tank and the biochemical tank A.

[0049] The test focused on the COD (chemical oxygen demand) concentration changes in the sewage treatment plant's inlet and outlet water. The COD concentration data during normal operation was continuously monitored and recorded, with sampling and testing every 48 hours, and the monitoring period was 14 days.

[0050] Comparative Example 2

[0051] This comparative example was conducted in the same sewage treatment plant as Example 2. The only difference is that this comparative example selected biochemical pool B as the test object, and the sewage treatment system provided by the present invention was not installed on the sludge return pipe between the biochemical pool B and the sedimentation tank.

[0052] Test results and analysis

[0053] The experimental data statistics of Example 1 and Comparative Example 1 (as shown in Figure 2As shown in the figure, it is revealed that in Example 1, by introducing the petroleum and petrochemical wastewater treatment device provided by the present invention, its COD (chemical oxygen demand) removal effect shows significant superiority compared to the traditional treatment process of Comparative Example 1. Specifically, the inlet COD concentration was stably maintained in the range of 338 to 394 mg / L during the experiment, while the effluent COD concentration after treatment with the optimized process was significantly reduced, from the original 195 to 253 mg / L to 115 to 140 mg / L. This significant improvement in COD removal rate not only reflects the outstanding advantages of the present invention in improving sewage treatment efficiency, but also means that the effluent water quality has reached more stringent environmental protection standards, thereby ensuring that the wastewater has been effectively purified before discharge.

[0054] The experimental data statistics of Example 2 and Comparative Example 2 (such as Figure 3 (as shown) further indicates that: in Example 2, faced with a sewage treatment plant with a daily processing capacity of up to 7,500 cubic meters and a large fluctuation in the influent COD concentration between 536 and 702 mg / L, the optimized process provided by the present invention exhibits a good COD removal capacity. Compared with the traditional process in which the effluent COD concentration is as high as 340 to 512 mg / L when facing water quality fluctuations, the effluent COD concentration after optimization of the process of the present invention can be stably controlled between 177 and 282 mg / L. This result not only verifies the effectiveness of the present invention in improving sewage treatment efficiency, but also shows that the optimized process has stronger adaptability and stability when dealing with complex water quality conditions.

[0055] In summary, the integrated system for treating petroleum and petrochemical wastewater proposed in the present invention effectively enhances the ability of microorganisms in the biochemical pool to degrade pollutants by returning the dense sludge loaded with exclusive bacteria to the aerobic pool, and significantly improves the stability of the microbial ecology. This not only significantly improves the efficiency and quality of sewage treatment, but also provides a new technical path for the effective treatment of petroleum and petrochemical wastewater.

[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A petroleum and petrochemical wastewater treatment system, characterized in that: The treatment system comprises an exclusive bacterial strain in-situ production device (1), a dense sludge separation device (5) and a bacterial strain sludge loading device (6); The dense sludge separation device (5) is provided with a sludge inlet (11), a light sludge outlet (12) and a dense sludge outlet (13) on its surface, and a plurality of sludge cyclone tubes (4) are arranged inside, wherein the sludge cyclone tubes (4) are connected to each other through internal pipelines and are in communication with the sludge inlet (11), the light sludge outlet (12) and the dense sludge outlet (13); The bacterial strain sludge loading device (6) is provided with a bacterial strain sludge loading device inlet (10) and a bacterial strain sludge loading device outlet (9); the bacterial strain sludge loading device inlet (10) is connected to the bacterial strain outlet (8) and the dense sludge outlet (13) provided at the bottom of the dedicated bacterial strain in-situ production device (1) through a bacterial strain delivery pipeline (2) and a dense sludge delivery pipeline (3) respectively; The treatment system is arranged between the sludge return pipes of the sedimentation tank and the biochemical tank of the sewage treatment plant, the sludge inlet (11) is connected to the sludge return pipe of the sedimentation tank, and the bacterial sludge loading device outlet (9) is connected to the biochemical tank through a pipeline.

2. The petroleum and petrochemical wastewater treatment system according to claim 1, characterized in that: The sludge cyclone tube (4) is conical, comprising a cylindrical section and a conical section. The sludge cyclone tube (4) is respectively provided with an inlet, an overflow port and an underflow port, which are connected to the sludge inlet (11), the light sludge outlet (12) and the dense sludge outlet (13).

3. The petroleum and petrochemical wastewater treatment system according to claim 1, characterized in that: The light sludge outlet (12) is arranged at the top, and the dense sludge outlet (13) is arranged at the bottom.

4. The petroleum and petrochemical wastewater treatment system according to claim 1, characterized in that: The number of the sludge cyclone tubes (4) is 4.

5. The petroleum and petrochemical wastewater treatment system according to claim 1, characterized in that: The bacterial strain sludge loading device (6) is composed of a hollow circular tube, and the circular tube is an internally threaded tube.

6. The petroleum and petrochemical wastewater treatment system according to claim 1, characterized in that: The bacterial strain sludge loading device (6) is fixed by a fixing frame (7).

7. The petroleum and petrochemical wastewater treatment system according to claim 1, characterized in that: The dedicated bacterial strain in-situ production device (1) is used to propagate a dedicated bacterial strain that specifically treats specific harmful organic substances in petroleum and petrochemical wastewater.

8. The petroleum and petrochemical wastewater treatment system according to claim 1, characterized in that: The exclusive bacterial strains are microorganisms that are isolated, screened, domesticated with raw water, and then biologically expanded.

9. The petroleum and petrochemical wastewater treatment system according to claim 1, characterized in that: The dedicated strain in-situ production device (1) is provided with temperature, pressure and dissolved oxygen control devices.

10. The petroleum and petrochemical wastewater treatment system according to claim 1, characterized in that: The inner hollow round tubes of the bacterial strain conveying pipeline (2) and the bacterial strain sludge loading device (6) are provided with a water bath jacket layer on the outside.

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