Improved oily water treatment device

Abstract

The utility model discloses an improved oily water treatment device, and belongs to the technical field of sewage treatment. The device comprises a sewage storage tank, a gravity oil separation tank, an air floatation tank, a biochemical tank, a heating storage tank, a waste oil tank, a dosing tank and a dehydration system. According to the device, primary oil-water separation is performed from a pretreatment stage through a heating system of the heating storage tank, so that the operation load of subsequent units is reduced; a waste oil tank is added, treated oily sewage with still high oil content is pumped into the waste oil tank, floating oil at the upper end of the waste oil tank is collected through a floating oil device, oily sewage at the bottom repeatedly passes through an oil separation floating oil device to be retreated, and the water content of the waste oil is reduced until effluent reaches the standard of a biochemical system. Finally, the purpose of improving the oil-water separation effect of the gravity oil-separation air floatation equipment is achieved. The device performs repeated treatment according to the oil content index of the effluent of the oil separation floating device, reduces the chemical consumption and the power consumption, improves the separation effect, and has positive influences on the environment and the economy.

Description

Technical Field

[0001] The utility model belongs to the technical field of sewage treatment, and specifically relates to an improved oily sewage treatment device. Background Art

[0002] Ship oily wastewater contains oil and some solid impurities and suspended solids that exceed the national sewage discharge standards. The dispersed state of the oil is mainly floating oil and dispersed oil, and does not contain emulsified oil with surfactants. The results of the particle size distribution of dispersed oil droplets show that oil with a particle size of less than 10 microns accounts for about 15% of the oil concentration. Ship ballast water contains a large amount of sludge, which must be treated to separate the oil and sludge in the ballast water, and the floating oil is reused. The sludge is dehydrated and transported to a solid waste treatment plant for treatment. Common oily wastewater separation technologies include Fenton oxidation and centrifugation. These oil separation technologies have been widely used, but they all have certain defects. Among them, Fenton oxidation reagents consume a lot of energy and have high operating costs; centrifugal technology has high power consumption costs and also leads to high operating costs. Utility Model Content

[0003] In order to solve the problems existing in the prior art, the utility model provides an improved oily wastewater treatment device, which adopts gravity oil separation and air flotation technology to reduce drug consumption and power consumption, while improving the separation effect.

[0004] The technical solution adopted by the utility model is: an improved oily wastewater treatment device, which includes a wastewater storage tank, a dehydration system and a biochemical pool, the water outlet of the wastewater storage tank is connected to the water inlet of the gravity oil separator, the water outlet of the gravity oil separator is connected to the water inlet of the air flotation tank, the air flotation outlet is divided into two branches through a water quality detector, and is respectively connected to the water inlet of the heating tank and the biochemical pool; the water outlet of the heating tank is connected back to the wastewater storage tank;

[0005] The device is also provided with a dosing tank, which is connected to the dosing ports of the gravity oil separator and the air flotation tank respectively through a dosing pump;

[0006] The gravity oil separator is divided into an oil separation flocculation zone and an oil separation water outlet zone by a middle partition. A wall tube is arranged on one side of the oil separation flocculation zone of the middle partition. A wall tube bottom inlet and a wall tube upper outlet are arranged on the wall tube. The wall tube upper outlet is connected to the middle partition outlet of the middle partition. A water outlet partition is also arranged in the oil separation water outlet zone. An oil separation slag outlet is arranged at the bottom of the gravity oil separator;

[0007] The flotation tank is divided into an air flotation flocculation zone and an air flotation zone by a flocculation water retaining plate, and the air flotation flocculation zone and the air flotation zone are connected through a flocculation water outlet; a dissolved air pipe connected to a fan is arranged at the bottom of the air flotation zone, and an air flotation oil outlet and an air flotation water outlet are arranged on one side of the air flotation zone; and an air flotation slag outlet is arranged at the bottom of the air flotation tank;

[0008] The oil outlet of the sewage storage tank, the oil separator and floating oil outlet of the gravity oil separator, the flotation oil outlet of the flotation tank, and the oil outlet of the heating storage tank are connected to the waste oil tank, and the oil separator and slag outlet of the gravity oil separator and the flotation slag outlet of the flotation tank are connected to the dehydration system.

[0009] Stirring devices are arranged in the oil separation flocculation zone and the air flotation flocculation zone.

[0010] In the oil separation water outlet area, an oil floating baffle is arranged in front of the middle baffle outlet.

[0011] A heating jacket is arranged at the bottom of the heating storage tank.

[0012] The beneficial effects of the utility model are as follows: the oily sewage is pumped to the oily sewage treatment workshop through a lifting pump, PAC and PAM are added to the oily sewage and stirred and mixed, and then separated by gravity, the floating oil on the upper end is collected, and the deoiled water enters the flotation section, and PAC and PAM are added and stirred and mixed, and then aerated, and the sediment enters the dehydration room for dehydration, and the deoiled sewage is pumped into the sewage treatment system through a lifting pump for biochemical treatment. By adding an oil storage and heating system, an oil-water separation is performed from the pretreatment stage to reduce the operating load of subsequent units; a waste oil tank is added to pump the oily sewage with a high oil content after treatment into the waste oil tank, the floating oil on the upper end of the waste oil tank is collected through an oil floating device, and the oily sewage at the bottom is repeatedly reprocessed through an oil separation flotation device to reduce the water content of the waste oil, until the effluent reaches the standard for discharge into the biochemical system, and finally the purpose of improving the oil-water separation effect of the gravity oil separation flotation equipment is achieved.

[0013] The repeated treatment is determined according to the oil content index of the effluent from the oil separation flotation device. During the treatment process, the oil removal efficiency is improved by heating and adsorbing the floating oil on the upper end of the storage tank. The device ultimately ensures that the effluent meets the standard for a long time. Compared with Fenton oxidation, centrifugation and other technologies, it reduces drug consumption and energy consumption, improves separation effect, and has a positive impact on the environment and economy. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 The present invention is a flow chart of an improved oily wastewater treatment device.

[0015] In the figure: 1, sewage storage tank, 2, gravity oil separator, 2a, oil separator flocculation area, 2b, oil separator water outlet area, 2c, middle partition, 2d, middle partition outlet, 2e, wall tube, 2f, wall tube bottom inlet, 2g, wall tube upper outlet, 2h, floating oil partition, 2i, water outlet partition, 2j, oil separator slag outlet, 2k, oil separator floating oil outlet, 3, flotation tank, 3a, flotation flocculation area, 3b, flotation area, 3c, flocculation water baffle, 3d, flocculation water outlet, 3e, dissolved air pipe, 3f, fan, 3g, flotation oil outlet, 3h, flotation water outlet, 3j, flotation slag outlet, 4, water quality detector, 5, biochemical pool, 6, heating storage tank, 6a, heating jacket, 7, waste oil tank, 8, dosing tank, 8a, dosing pump, 9, dehydration system. DETAILED DESCRIPTION

[0016] The present invention is described below with reference to the accompanying drawings and specific implementation methods:

[0017] Figure 1 The flow chart of an improved oily wastewater treatment device is shown, in which the oily wastewater treatment device includes a wastewater storage tank 1, a gravity oil separator 2, an air flotation tank 3, a water quality detector 4, a biochemical tank 5, a heating tank 6, a waste oil tank 7, a dosing tank 8 and a dehydration system 9. The water outlet of the wastewater storage tank 1 is connected to the water inlet of the gravity oil separator 2, the water outlet of the gravity oil separator 2 is connected to the water inlet of the air flotation tank 3, and the air flotation outlet 3h is divided into two branches through the water quality detector 4, which are respectively connected to the water inlets of the heating tank 6 and the biochemical tank 5; a heating jacket 6a is provided at the bottom of the heating tank 6, and the water outlet of the heating tank 6 is connected back to the wastewater storage tank 1. The dosing tank 8 is connected to the dosing ports of the gravity grease trap 2 and the flotation tank 3 respectively through the dosing pump 8a; the oil outlet of the sewage storage tank 1, the oil separator and floating oil outlet 2k of the gravity grease trap 2, the flotation oil outlet 3g of the flotation tank 3, and the oil outlet of the heating storage tank 6 are connected to the waste oil tank 7, and the oil separator and slag outlet 2j of the gravity grease trap 2 and the flotation slag outlet 3h of the flotation tank 3 are connected to the dehydration system 9.

[0018] The gravity oil trap 2 is divided into an oil-separation flocculation area 2a and an oil-separation water outlet area 2b by a middle partition 2c, and a stirring device is provided in the oil-separation flocculation area 2a. The middle partition 2c is provided with a wall tube 2e on one side of the oil-separation flocculation area 2a, and the wall tube 2e is provided with a wall tube bottom inlet 2f and a wall tube upper outlet 2g, and the wall tube upper outlet 2g is connected with the middle partition outlet 2d of the middle partition 2c; in the oil-separation water outlet area 2b, an oil floating partition 2h is provided in front of the middle partition outlet 2d, and a water outlet partition 2i is also provided in front of the water outlet, and an oil separation slag outlet 2j is provided at the bottom of the gravity oil trap 2.

[0019] The flotation tank 3 is divided into a flotation flocculation zone 3a and a flotation zone 3b by a flocculation water retaining plate 3c, and the flotation flocculation zone 3a and the flotation zone 3b are connected through a flocculation water outlet 3d; a stirring device is arranged in the flotation flocculation zone 3a, a dissolved air pipe 3e connected to a fan 3f is arranged at the bottom of the flotation zone 3b, and a flotation oil outlet 3g and a flotation water outlet 3h are arranged on one side of the flotation zone 3b; a flotation slag outlet 3j is arranged at the bottom of the flotation tank 3.

[0020] When the above technical solution is adopted, the floating oil in the sewage storage tank 1 is discharged to the waste oil tank 7, the remaining oily sewage enters the gravity oil separator 2, the oily sewage enters the oil separator flocculation area 2a and is flocculated with the agent added by the dosing tank 8 under the stirring of the stirring device, and then the heavy oil and sediment are discharged to the dehydration system 9 through the oil separator slag outlet 2j, and the floating oil is discharged to the waste oil tank 7 through the oil separator floating oil outlet 2k. The treated oily wastewater enters the wall tube 2e through the bottom inlet 2f of the wall tube, and then enters the oil-water separation water outlet area 2b through the upper outlet 2g of the wall tube and the middle partition outlet 2d. After passing through the floating oil partition 2h, a small amount of floating oil and a small amount of heavy oil and sediment are separated again from the oily wastewater. The floating oil is also discharged to the waste oil tank 7 through the oil-water separation floating oil port 2k, and the heavy oil and sediment are also discharged to the dehydration system 9 through the oil-water separation slag outlet 2j. The oily wastewater then passes through the bottom of the water outlet partition 2i and is discharged from the outlet of the gravity oil-water separator 2 to the flotation flocculation area 3a of the flotation tank 3. The oily sewage in the flotation flocculation area 3a and the reagent added by the dosing tank 8 are flocculated under the stirring of the stirring device. After flocculation, the oily sewage enters the flotation area 3b through the flocculation outlet 3d. The oil droplets and flocs in the oily sewage contact the bubbles generated by the air dissolving tube 3e. The water flow continues to flow backward. Some oil droplets and flocs adhere to the bubbles and float directly to form floating oil. A small amount of large flocs sink to the bottom of the pool. The floating oil is discharged to the waste oil tank 7 through the flotation outlet 3g. The sediment at the bottom is discharged through the flotation outlet 3g. The slag outlet 3h is discharged to the dehydration system 9; after the oil pollution in the flotation tank 3 is discharged through the flotation outlet 3h, it is tested by the water quality detector 4. If it meets the standard, it is discharged into the biochemical tank 5 for subsequent treatment. If the oil content is too high, it is discharged into the heating storage tank 6 for heating and static sedimentation. The bubbles generated by the heating carry part of the oil droplets to float up, and the upper floating oil is discharged into the waste oil tank 7. The remaining oily water is returned to the oil pollution storage tank 1 for another separation until the water quality test is qualified and enters the subsequent treatment.

Claims

1. An improved oily wastewater treatment device, comprising a wastewater storage tank (1), a dehydration system (9) and a biochemical pool (5), characterized in that: In the device, the sewage storage tank (1), the gravity oil separator (2), and the flotation tank (3) are connected in sequence by pipelines; the flotation outlet (3h) is divided into two branches through a water quality detector (4), which are respectively connected to the water inlets of the heating tank (6) and the biochemical tank (5); the outlet of the heating tank (6) is connected back to the sewage storage tank (1); The device is also provided with a dosing tank (8), which is connected to the dosing ports of the gravity oil separator (2) and the flotation tank (3) respectively through a dosing pump (8a); The gravity oil separator (2) is divided into an oil separation flocculation zone (2a) and an oil separation water outlet zone (2b) by a middle partition (2c); the middle partition (2c) is provided with a wall tube (2e) on one side of the oil separation flocculation zone (2a); a wall tube bottom inlet (2f) and a wall tube upper outlet (2g) are provided on the wall tube (2e); the wall tube upper outlet (2g) is communicated with a middle partition outlet (2d) of the middle partition (2c); a water outlet partition (2i) is provided in the oil separation water outlet zone (2b) near the water outlet; and an oil separation slag outlet (2j) is provided at the bottom of the gravity oil separator (2); The flotation tank (3) is divided into an air flotation flocculation zone (3a) and an air flotation zone (3b) by a flocculation water baffle (3c); the air flotation flocculation zone (3a) and the air flotation zone (3b) are connected via a flocculation water outlet (3d); an air dissolving pipe (3e) connected to a fan (3f) is provided at the bottom of the air flotation zone (3b); an air flotation oil outlet (3g) and an air flotation water outlet (3h) are provided on one side of the air flotation zone (3b); and an air flotation slag outlet (3j) is provided at the bottom of the air flotation tank (3); The oil outlet of the sewage storage tank (1), the oil separation and floating oil outlet (2k) of the gravity oil separator (2), the flotation oil outlet (3g) of the flotation tank (3), and the oil outlet of the heating storage tank (6) are connected to the waste oil tank (7), and the oil separation and slag outlet (2j) of the gravity oil separator (2) and the flotation slag outlet (3j) of the flotation tank (3) are connected to the dehydration system (9).

2. The improved oily wastewater treatment device according to claim 1 is characterized in that: Stirring devices are provided in both the oil separation flocculation zone (2a) and the air flotation flocculation zone (3a).

3. The improved oily wastewater treatment device according to claim 1 is characterized in that: In the oil-separating water outlet area (2b), an oil floating baffle (2h) is arranged in front of the middle baffle outlet (2d).

4. The improved oily wastewater treatment device according to claim 1 is characterized in that: A heating jacket (6a) is provided at the bottom of the heating storage tank (6).

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