CN216711854U - Device for treating sewage by dry distillation - Google Patents

Abstract

The utility model discloses a device for treating dry distillation sewage, which comprises a pretreatment system, a DPN biochemical system, an enhanced biochemical system and an advanced treatment system which are connected in sequence, wherein the pretreatment system comprises a demulsification air flotation tank and a buffer water tank which are connected; the DPN biochemical system comprises a denitrification tank, a decarburization/nitrosification tank a, a sub-digestion tank and a primary sedimentation tank which are arranged in sequence according to a wastewater treatment sequence; the intensified biochemical system comprises an Anammox tank, a secondary sedimentation tank, an anaerobic hydrolysis tank, a decarburization/nitrosification tank b, a post-denitrification tank and a final sedimentation tank which are arranged in sequence; the advanced treatment system comprises an intermediate water tank, a multi-media filter, an ozone catalytic tower and an aeration biological filter. The system has the characteristics that the water quality characteristics of the dry distillation sewage are fully considered, each treatment unit is designed in a refined and economical mode, various pollutants in the dry distillation sewage are removed to the maximum extent, the operation cost is reduced to a lower level, and the effluent reaches the discharge standard.

Description

Device for treating sewage by dry distillation

Technical Field

The utility model relates to the technical field of wastewater treatment, in particular to a device for treating dry distillation sewage.

Background

The shale oil production process can be divided into three parts, namely oil shale treatment, oil shale dry distillation and oil gas condensation and recovery. The sources of the dry distillation sewage mainly comprise finished oil dehydration, boiler and power station gas dehydration, desulfurization liquid, water tank sewage, fan cooling water, ground washing sewage and the like. The main pollution is from dry distillation sewage, namely sewage discharged from the outside of the washing tower. The sewage generated in the shale oil refining and dry distillation process contains various pollutants, has complex components and higher concentration, contains a large amount of toxic or difficultly-degradable substances, and belongs to difficultly-degradable industrial sewage.

The shale oil dry distillation sewage is characterized by high water temperature, high pH value and extremely high chroma; the sewage pollutant content is extremely high, the COD concentration is as high as 4000-; the concentration of petroleum is higher, and reaches 500-1200 mg/L; the concentration of ammonia nitrogen (NH4+ -N) and the concentration of Total Nitrogen (TN) are higher, generally being 3500mg/L at 2000 and 4500mg/L at 3000; the concentration of phenols (mainly volatile phenol) was 150-300 mg/L. The sewage is complex in composition, contains a large amount of organic matters which are difficult to degrade, mainly comprises volatile phenol, polyhydric phenol, aromatic organic matters, heterocyclic organic matters and the like, and has high pollutant concentration, poor biodegradability and low C/N.

The sewage which does not reach the standard contains various pollutants with higher concentration, and if the sewage is discharged to a natural water body, serious pollution is caused. The main solution at present includes that sewage is directly used for cooling shale subjected to high-temperature carbonization, but the sewage which does not reach the standard contains pollutants with higher concentration, and the pollutants are volatilized into the atmosphere after being contacted with hot high-temperature shale, so that more serious air pollution is caused.

SUMMERY OF THE UTILITY MODEL

Aiming at the problems of high standard discharge difficulty and high cost of the conventional carbonization sewage treatment, the utility model provides a carbonization sewage treatment device, which reduces the operation cost to a lower level and ensures that the effluent reaches the discharge standard.

In order to achieve the purpose, the application provides a device for treating the dry distillation sewage, which comprises a pretreatment system, a DPN biochemical system, an enhanced biochemical system and a deep treatment system which are sequentially connected, wherein the pretreatment system comprises a demulsification air flotation tank and a buffer water tank which are connected; the DPN biochemical system comprises a denitrification tank, a decarburization/nitrosification tank a, a sub-digestion tank and a primary sedimentation tank which are sequentially arranged according to a wastewater treatment sequence, wherein the decarburization/nitrosification tank a is connected with the bottom of the denitrification tank through a reflux pump, and the effluent of the primary sedimentation tank is connected with the top of the sub-digestion tank through the reflux pump; the intensified biochemical system comprises an Anammox tank, a secondary sedimentation tank, an anaerobic hydrolysis tank, a decarburization/nitrosation tank b, a postposition denitrification tank and a final sedimentation tank which are arranged in sequence, wherein the top of the Anammox tank is connected with a sub-digestion tank, the bottom of the secondary sedimentation tank is connected to the Anammox tank through a reflux pump, and the final sedimentation tank is connected to the postposition denitrification tank through the reflux pump; the deep treatment system comprises an intermediate water tank, a multi-media filter, an ozone catalytic tower and a biological aerated filter, wherein a water inlet of the intermediate water tank is connected with a water outlet of a final sedimentation tank, a water outlet of the intermediate water tank is connected with the multi-media filter through a filter lift pump, a backwashing port of the intermediate water tank is respectively connected with the multi-media filter, the ozone catalytic tower and the biological aerated filter through a backwashing water pump, and the multi-media filter is connected with the biological aerated filter through the ozone catalytic tower.

Furthermore, the demulsification air flotation tank is respectively connected with the demulsification adding pump, the sulfuric acid adding pump and the raw water pump, an oil disturbing plate is arranged at the top of the demulsification air flotation tank, the upper-layer floating oil is collected by the oil disturbing plate and discharged to a floating oil collecting tank, and a dissolved air fan is arranged at the bottom of the demulsification air flotation tank.

Controlling the pH value of the reaction to be between 6.2 and 7.8 in a demulsification air flotation tank, controlling the water temperature to be between 35 and 40 ℃, keeping the reaction temperature for 30 to 40min, controlling the working water depth to be 15 to 25m, controlling the length-width ratio to be not less than 4, and controlling the surface load to be 5 to 10m³/m²·h。

Furthermore, a pH probe is arranged at the water inlet end of the demulsification air flotation tank, a pH adjusting agent adding point is positioned on a pipeline mixer of an air flotation water inlet pipeline, the effluent of the demulsification air flotation tank automatically flows into a buffer water tank, the buffer water tank is used for temporarily storing the sewage after oil separation, a buffer water pump lifts the sewage to a denitrification tank, and a temperature controller is arranged in the buffer water tank to control the water temperature to be 35-40 ℃.

Furthermore, the denitrification tank is of a plug flow type, MBBR (moving bed biofilm reactor) filler is filled in the tank, 3-5 stirrers and sleeves are arranged in the tank, and stainless steel mesh intercepting filler is arranged at the interval of the sleeves and a final water outlet; effluent of the denitrification tank automatically flows to a decarburization/nitrosification tank a, MBBR filler is filled in the decarburization/nitrosification tank a, an aeration fan (one system is arranged at the bottom and is led out from a branch cylinder together with other air units) and a reflux pump are arranged at the bottom, the reflux pump refluxes mixed liquid to a water inlet of the denitrification tank, a lifting pump is further arranged in the decarburization/nitrosification tank a, and stainless steel mesh intercepting filler is arranged at inlets of the two pumps.

Furthermore, the effluent of the decarburization/nitrosation tank a automatically flows to a nitrosation tank, MBBR filler is filled in the nitrosation tank, an aeration fan is arranged at the bottom of the nitrosation tank, a stainless steel mesh intercepting filler is arranged at a water outlet of the nitrosation tank, a primary water outlet of the nitrosation tank is connected to a primary sedimentation tank, the primary sedimentation tank reflows sludge to a water inlet of the nitrosation tank through a reflux pump, and residual sludge is periodically and manually discharged.

Furthermore, a secondary water outlet of the nitrosation tank is connected to an Anammox tank, the Anammox tank is connected to an anaerobic hydrolysis tank through a secondary sedimentation tank, MBBR filler is filled in the anaerobic hydrolysis tank, and 1-2 stirrers and sleeves are arranged in the anaerobic hydrolysis tank.

Furthermore, the effluent of the anaerobic hydrolysis tank automatically flows to a decarburization/nitrosification tank b, MBBR filler is filled in the decarburization/nitrosification tank b, an aeration fan is arranged at the bottom of the decarburization/nitrosification tank b, stainless steel mesh intercepting filler is arranged at a water outlet of the decarburization/nitrosification tank b, the effluent of the decarburization/nitrosification tank b automatically flows to a rear denitrification tank, the rear denitrification tank is respectively connected with a denitrification carbon source feeding pump and a raw water pump, the MBBR filler is filled in the denitrification tank, 1-2 stirrers and sleeves are arranged, the stainless steel mesh intercepting filler is arranged at the water outlet of the denitrification tank, the effluent of the rear denitrification tank enters a final sedimentation tank, the sludge is refluxed to a water inlet of the decarburization/nitrosification tank b through a reflux pump, and the residual sludge is periodically and manually discharged.

Furthermore, the effluent of the final sedimentation tank is temporarily stored in an intermediate water tank, and the intermediate water tank pumps sewage in the tank into the multi-media filter through a filtering and lifting pump during normal operation; during backwashing, the filtering water pump is manually stopped, the backwashing water pump is started, and the multi-media filter, the ozone catalytic tower and the biological aerated filter are correspondingly backwashed; the middle water tank is provided with an ultrahigh overflow port and a liquid level float switch, the two pumps at high water level can be started, and the two pumps at low water level are forcibly stopped.

Furthermore, the multi-media filter backflushing can take two forms, one is manual operation, and the other is automatic backflushing through a FLECK valve system carried by standard equipment. Back washing fans are arranged in the multi-medium filter and the ozone catalytic tower.

As a further step, the effluent of the multi-media filter enters an ozone catalytic tower, the ozone catalytic tower is filled with a catalyst, field compressed air (process air or an air compressor) enters an ozone generator, ozone generated by the ozone generator enters the lower part of the tower and is diffused into water through a microporous aeration disc, and the treated sewage enters the biological aerated filter; the top of the ozone catalytic tower is provided with an air outlet which is sent to the outdoor for emptying through a pipeline.

As a further step, an aeration fan is arranged at the bottom of the biological aerated filter, and the air and the water inside the biological aerated filter flow from bottom to top in the same direction; during backwashing, the filtration lift pump is manually stopped, the power supply of the ozone generator is closed (meanwhile, an inlet and outlet gas circuit valve of the ozone generator is closed), and a valve on a BAF aeration pipeline is closed; and after the back flushing is finished, starting the filtration lift pump, and simultaneously starting the power supply of the ozone generation system and the corresponding gas circuit valve.

Compared with the prior art, the technical scheme adopted by the utility model has the advantages that: the sewage enters each reaction system in turn by adopting a self-flowing or pump lifting mode, pollutants such as COD, NH4+ -N, TN and the like in the water are removed gradually, and the system has the characteristics that the water quality characteristics of the dry distillation sewage are fully considered, each treatment unit is designed in a refined and economical mode, each pollutant in the dry distillation sewage is removed to the maximum extent, the operation cost is reduced to a lower level, and the effluent reaches the discharge standard.

Drawings

FIG. 1 is a schematic view of a structure of a wastewater treatment apparatus by dry distillation;

the sequence numbers in the figures illustrate: 1. a demulsification air flotation tank; 2. a floating oil collecting tank; 3. a buffer pool; 4. a denitrification tank; 5. a decarburization/nitrosification pool a; 6. a sub-digester; 7. a primary sedimentation tank; 8. an Anammox pool; 9. a secondary sedimentation tank; 10. an anaerobic hydrolysis tank; 11. a decarbonization/nitrosation tank b; 12. a back denitrification tank is arranged; 13. a final sedimentation tank; 14. a middle water tank; 15. a filtration lift pump; 16. backwashing the water pump; 17. a multi-media filter; 18. an ozone catalytic tower; 19. an aeration biological filter; 20. an ozone generator.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the application, i.e., the embodiments described are only a subset of, and not all embodiments of the application. The components of the embodiments of the present application, generally described and illustrated in the figures herein, can be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present application, presented in the accompanying drawings, is not intended to limit the scope of the claimed application, but is merely representative of selected embodiments of the application. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present application without making any creative effort, shall fall within the protection scope of the present application.

Example 1

As shown in FIG. 1, in the present example, a shale oil carbonized sewage is treated by the above apparatus for treating carbonized sewage, and the main water quality indexes are shown in Table 1:

TABLE 1

Item	Unit of	Numerical value
			Chemical Oxygen Demand (COD)	mg/L	5100
Biochemical oxygen demand	mg/L	1400
			Suspended matter	mg/L	270.0
Volatile phenols	mg/L	240.0
			Petroleum products	mg/L	800
Ammonia nitrogen	mg/L	2752

The dry distillation wastewater after oil separation enters a demulsification air flotation tank with a demulsifier feeding pump to remove oil and COD, the reaction pH is controlled to be 6.6, the water temperature is 36 ℃, the retention time is 32min, the working water depth is 18m, the length-width ratio is 5, and the surface load is 6m³/m²H, a sulfuric acid feeding pump is linked with a raw water pump, the upper-layer floating oil is collected through an oil-disturbing plate and discharged to a floating oil collecting tank, the discharged water automatically flows into a buffer water tank to temporarily store sewage, and the water temperature is controlled to be 35 ℃; the pH probe is arranged at the water inlet end of the demulsification air floatation tank, the pH adding point is arranged on a pipeline mixer of an air floatation water inlet pipeline, and the petroleum content of the effluent is reducedThe concentration is less than 55mg/L, and the COD is 3800 mg/L.

Then the wastewater enters a plug-flow denitrification tank through a buffer water pump to simultaneously remove carbon and nitrogen, remove most of total phenol and reduce the biological inhibition effect of the total phenol on a subsequent biochemical unit, MBBR filler is filled in the tank, 3 stirrers and sleeves are arranged, and stainless steel mesh intercepting filler is arranged at the interval between the sleeves and a final water outlet.

Then the mixture flows into a decarburization/nitrosification pool a automatically, MBBR filler is filled in the pool, an aeration fan (one system is arranged and is led out from a branch cylinder together with other air units) continuously supplies air for 24 hours, a reflux pump refluxes the mixed liquid to a water inlet of a denitrification pool, a lifting pump is arranged in the pool, stainless steel mesh intercepting filler is arranged at the inlets of two pumps, and more than 50 percent of COD and more than 50 percent of NH are removed₄ ⁺-N。

Then automatically flows into a sub-digestion tank, MBBR filler is filled in the tank, a stainless steel mesh is arranged at a water outlet to intercept the filler, an aeration fan continuously supplies air for 24 hours, and further nitrosation reaction is carried out to reduce NH₄ ⁺-N, control of NH₄ ⁺-N、NO₂ ^--N and NO₃-the ratio of N is 1: 1: 0.2.

after passing through a DNP biochemical system, the wastewater does not meet the discharge standard, and the TN is removed to be below 400mg/L by flowing through an Anammox tank automatically.

Then automatically flows into an anaerobic hydrolysis tank through a secondary sedimentation tank, MBBR filler is filled in the tank, 1 stirrer and sleeve are arranged in the tank, difficultly degraded COD such as heterocyclic compounds, polycyclic aromatic hydrocarbon and the like is hydrolyzed, and organic nitrogen is converted into NH₄ ⁺N, increasing the B/C ratio to 0.45.

Then automatically flows into a decarburization/nitrosification tank b, MBBR filler is filled in the tank, a stainless steel mesh is arranged at a water outlet to intercept the filler, an aeration fan continuously supplies air for 24 hours, COD effluent is controlled to be about 80mg/L, and NH is added₄ ⁺The concentration of-N is about 9 mg/L.

Then the wastewater flows into a post-denitrification tank, MBBR filler is filled in the post-denitrification tank, 2 stirrers and sleeves are arranged in the post-denitrification tank, a stainless steel net intercepting filler is arranged at a water outlet, a denitrification carbon source feeding pump is linked with a raw water pump, and the concentration of TN in the discharged water is controlled by feeding the denitrification carbon source sodium acetate.

And then the sludge flows into a final sedimentation tank, the sludge flows back to a water inlet of the decarburization/nitrosification tank b through a sludge return pump in the final sedimentation tank, and the residual sludge is periodically and manually discharged.

Then the wastewater enters an advanced treatment system and automatically flows into an intermediate water tank, the intermediate water tank has the function of temporarily storing the effluent of the final sedimentation tank, and the sewage in the tank is pumped into a multi-media filter by a filtering and lifting pump during normal operation; during backwashing, the filtration lift pump is manually stopped, and the backwashing water pump is started to perform corresponding backwashing; the middle water tank is provided with an ultrahigh overflow port and a liquid level float switch, the two pumps at high water level can be started, and the two pumps at low water level are forcibly stopped.

Then the wastewater flows into a multi-media filter, and the back flushing of the multi-media filter can be carried out by adopting a self-contained FLECK valve to remove the concentration of suspended solids to 8 mg/L;

the effluent is pumped into an ozone catalytic tower through a water pump, a catalyst with the filling ratio of 0.8 is filled in the tower, an on-site air compressor compresses air to enter an ozone generator, ozone generated by the ozone generator enters the lower part of the ozone catalytic tower and is diffused into water through a microporous aeration disc, and the effluent enters a biological aerated filter; the top of the ozone catalytic tower is provided with an air outlet, and the ozone catalytic tower is conveyed to the outdoor for emptying through a pipeline, so that COD is further removed to 60 mg/L.

And the air and the water in the aeration biological filter flow from bottom to top in the same direction, and the aeration fan continuously supplies air for 24 hours. During back washing, the filtration lift pump is manually stopped, the power supply of the ozone generator is closed (meanwhile, an inlet and outlet gas circuit valve of the ozone generator is closed), and a valve on the BAF aeration pipeline is closed. And (3) backflushing according to the same manual backflushing step of the multi-medium filter, starting a filtration lift pump after the backflushing is finished, and simultaneously starting a power supply of the ozone generator and a corresponding gas circuit valve to remove COD (chemical oxygen demand) and stabilize to 45-49 mg/L, so that the COD is discharged after reaching the standard.

The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. It is not intended to limit the utility model to the precise form disclosed, and obviously many modifications and variations are possible in light of the above teaching. The exemplary embodiments were chosen and described in order to explain certain principles of the utility model and its practical application to enable one skilled in the art to make and use various exemplary embodiments of the utility model and various alternatives and modifications as are suited to the particular use contemplated. It is intended that the scope of the utility model be defined by the claims and their equivalents.

Claims (10)

1. The device for treating the dry distillation sewage is characterized by comprising a pretreatment system, a DPN biochemical system, an enhanced biochemical system and a deep treatment system which are sequentially connected, wherein the pretreatment system comprises a demulsification air flotation tank and a buffer water tank which are connected; the DPN biochemical system comprises a denitrification tank, a decarburization/nitrosification tank a, a sub-digestion tank and a primary sedimentation tank which are sequentially arranged according to a wastewater treatment sequence, wherein the decarburization/nitrosification tank a is connected with the bottom of the denitrification tank through a reflux pump, and the effluent of the primary sedimentation tank is connected with the top of the sub-digestion tank through the reflux pump; the intensified biochemical system comprises an Anammox tank, a secondary sedimentation tank, an anaerobic hydrolysis tank, a decarburization/nitrosation tank b, a postposition denitrification tank and a final sedimentation tank which are arranged in sequence, wherein the top of the Anammox tank is connected with a sub-digestion tank, the bottom of the secondary sedimentation tank is connected to the Anammox tank through a reflux pump, and the final sedimentation tank is connected to the postposition denitrification tank through the reflux pump; the deep treatment system comprises an intermediate water tank, a multi-media filter, an ozone catalytic tower and a biological aerated filter, wherein a water inlet of the intermediate water tank is connected with a water outlet of a final sedimentation tank, a water outlet of the intermediate water tank is connected with the multi-media filter through a filter lift pump, a backwashing port of the intermediate water tank is respectively connected with the multi-media filter, the ozone catalytic tower and the biological aerated filter through a backwashing water pump, and the multi-media filter is connected with the biological aerated filter through the ozone catalytic tower.

2. The apparatus for dry distillation sewage treatment according to claim 1, wherein the demulsification air flotation tank is connected to the demulsifier feed pump, the sulfuric acid feed pump, and the raw water pump, respectively, and an oil turbulence plate is provided at the top of the demulsification air flotation tank, through which the upper-layer oil slick is collected and discharged to the oil slick collection tank.

3. The apparatus for dry distillation wastewater treatment according to claim 1, wherein a pH probe is disposed at the water inlet end of the emulsion breaking and flotation tank, a pH adjusting agent feeding point is disposed on a pipeline mixer of the flotation water inlet pipeline, the effluent of the emulsion breaking and flotation tank flows into a buffer water tank, the buffer water tank is used for temporarily storing the wastewater after oil separation, the wastewater is lifted to the denitrification tank by a buffer water pump, and a temperature controller is disposed in the buffer water tank to control the water temperature to be 35-40 ℃.

4. The device for treating the dry distillation sewage according to claim 1, wherein the denitrification tank is of a plug flow type, MBBR (moving bed biofilm reactor) filler is filled in the tank, 3-5 stirrers and sleeves are arranged in the tank, and stainless steel mesh intercepting filler is arranged at the interval between the sleeves and the final water outlet; effluent of the denitrification tank flows to a decarburization/nitrosification tank a automatically, MBBR fillers are filled in the decarburization/nitrosification tank a, an aeration fan and a reflux pump are arranged at the bottom of the decarburization/nitrosification tank a, the reflux pump refluxes the mixed liquid to a water inlet of the denitrification tank, a lifting pump is further arranged in the decarburization/nitrosification tank a, and stainless steel mesh intercepting fillers are arranged at inlets of the two pumps.

5. The apparatus for dry distillation sewage treatment according to claim 1, wherein the effluent of the decarbonization/nitrosation tank a flows into the nitrosation tank by itself, MBBR filler is filled in the nitrosation tank, an aeration fan is arranged at the bottom of the nitrosation tank, a stainless steel net is arranged at the water outlet to intercept the filler, a primary water outlet of the nitrosation tank is connected to a primary sedimentation tank, and the primary sedimentation tank returns the sludge to the water inlet of the nitrosation tank through a reflux pump.

6. The device for treating the dry distillation sewage according to claim 1, wherein a secondary water outlet of the nitrosation tank is connected to an Anammox tank, the Anammox tank is connected to an anaerobic hydrolysis tank through a secondary sedimentation tank, MBBR fillers are filled in the anaerobic hydrolysis tank, and 1-2 stirrers and sleeves are arranged in the anaerobic hydrolysis tank.

7. The device for treating dry distillation sewage according to claim 1, wherein the effluent of the anaerobic hydrolysis tank flows to a decarburization/nitrosation tank b, MBBR filler is filled in the decarburization/nitrosation tank b, an aeration fan is arranged at the bottom of the decarburization/nitrosation tank b, stainless steel mesh intercepting filler is arranged at a water outlet of the decarburization/nitrosation tank b, the effluent of the decarburization/nitrosation tank b flows to a post-denitrification tank, the post-denitrification tank is connected with a denitrification carbon source feeding pump and a raw water pump respectively, the MBBR filler is filled in the denitrification/nitrosation tank, 1-2 stirrers and sleeves are arranged, the stainless steel mesh intercepting filler is arranged at a water outlet of the post-denitrification tank, the effluent of the post-denitrification tank enters a final sedimentation tank, and the sludge flows back to a water inlet of the decarburization/nitrosation tank b through a reflux pump in the final sedimentation tank.

8. The apparatus for dry distillation sewage treatment according to claim 1, wherein the effluent of the final sedimentation tank is temporarily stored in an intermediate tank, and in normal operation, the intermediate tank pumps sewage in the tank into the multi-media filter through a filter lift pump; during back flushing, the filtering water pump is manually stopped, the back flushing water pump is started, and the multi-media filter, the ozone catalytic tower and the biological aerated filter are correspondingly back flushed.

9. The apparatus according to claim 1, wherein the effluent of the multi-media filter enters an ozone catalytic tower filled with catalyst, the on-site compressed air enters an ozone generator, the ozone generated by the ozone generator enters the lower part of the tower and is diffused into the water through a microporous aeration disc, and the treated sewage enters the biological aerated filter.

10. The apparatus for dry distillation sewage treatment as claimed in claim 1, wherein an aeration fan is provided at the bottom of the biological aerated filter, and the gas and water inside the biological aerated filter flow from bottom to top in the same direction.

Images