Waste water or feed liquid oil removal device and oil removal process

Abstract

The embodiment of the invention discloses a wastewater or feed liquid oil removal device and an oil removal process. A waste water or feed liquid oil removal device is of a hollow cavity structure and comprises a shell and an inner cavity, the inner cavity is divided into a steady flow area, a coalescence area and a separation area which are communicated, and the steady flow area is separated from the coalescence area through a pore plate; the flow stabilizing area is provided with a wastewater inlet, an elbow, a baffle plate and a sludge collecting bag; the coalescence area is provided with an egg support type corrugated plate and a mud collecting bag; open holes are respectively formed in the tops of the convex parts and the bottoms of the concave parts of the egg support type corrugated plate; and the separation area is provided with a light oil overflow port, a water outlet and a mud collecting bag. The device has a good removal effect on heavy oil, light oil, suspended solids and the like, the treatment cost is greatly reduced, meanwhile, the device is easy to operate, the integration degree is high, the occupied area is smaller, and the device has a good application prospect.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of wastewater treatment, and in particular to a wastewater or liquid oil removal device and an oil removal process. Background Art

[0002] At present, all walks of life will produce a large amount of oily wastewater or liquid, such as semi-coke / coking wastewater. Semi-coke adopts low-temperature distillation process in the production process, and the temperature is relatively low, resulting in a large amount of pollutants in the semi-coke wastewater that have not been oxidized at high temperature. This type of wastewater has high chromaticity, and the content of oil, COD, SS, etc. is relatively high, which is very difficult to treat. If this type of wastewater is not pre-treated, it will increase the subsequent phenol-ammonia recovery unit, deacidification tower, deamination tower, extraction tower, and fouling, causing the tower plate to be blocked and difficult to clean, which will lead to the failure of various indicators of the effluent to meet the standards. Due to the poor effect of pre-deoiling at the front end, the extraction process will lead to more third phases and serious loss of extractants, which seriously affect the normal operation of subsequent processes. The conventional pre-deoiling process is mainly gravity deoiling + flotation deoiling. The gravity sedimentation cycle is long and the oil removal effect is very limited. It is difficult to separate a large amount of floating oil and slag from the flotation effluent. During the flotation aeration, due to the high content of oil organic matter and a lot of foam, the liquid or foam overflows to the outside of the equipment, resulting in a poor operating environment and high maintenance costs.

[0003] CN216236320U proposes an anti-clogging type semi-coke wastewater oil removal device, which consists of four-stage oil removers, wherein the first-stage oil remover uses cyclone centrifugal action to perform preliminary separation of light oil and heavy oil, the second-stage and third-stage oil removers use coarse filter material and fine filter material for oil removal respectively, and in order to prevent the filter material from being blocked, stirring is added to the equipment, and the fourth-stage oil remover uses agglomeration material to further remove oil. This technology solves the problem of equipment blockage to a certain extent, but the investment in cyclone centrifugal equipment for the treatment of large amounts of semi-coke wastewater is too high, and stirring is added to the oil remover with added filter material. Although it solves the problem of blockage to a certain extent, during the stirring process, the oil originally separated will be further dissolved back into the water body, greatly reducing the oil removal effect.

[0004] CN215975226U proposes a ceramic ultrafiltration device for deoiling treatment of semi-coke wastewater. The device mainly adopts gravity deoiling + precision filtration + ceramic ultrafiltration process for deoiling. The device has a high separation effect on extremely small organic matter, but for semi-coke wastewater, the precision filter and ceramic membrane will be seriously blocked, and the cleaning cycle is frequent.

[0005] CN116282731A proposes a method for treating blue carbon phenol ammonia wastewater, which uses a two-stage oil-water separation device in series for pre-oil removal, which contains a demulsifier and an oil removal element, wherein the oil removal element is a super-oleophilic and hydrophobic material with a spatial mesh fiber structure. The two-stage oil-water separation device in series can separate suspended oil, emulsified oil, etc., and the device has a high degree of integration, but the device is designed as a tank structure, which is not easy to disassemble and clean, and is easy to cause pollution blockage of the device.

[0006] As for the oil removal technology in other industries, CN104843817A proposes a horizontal air flotation coupled corrugated plate oil removal method and device, which uses an oleophilic and hydrophobic corrugated plate coupled with a tree-branch type horizontal bubble generator, and makes the light oil float up under the action of bubbles and then isolates it through the oil separator to achieve oil-water separation. This corrugated plate is a hole in the convex part of the conventional corrugated plate, and with the help of the bubble generator, the light oil floats up to achieve oil-water separation. However, for the separation of suspended matter, it is necessary to tilt the corrugated plate so that it slides down the corrugated plate, but a bubble generator is arranged below the corrugated plate horizontally, and for water bodies with poor water quality, the problem of pore blockage is prone to occur. In order to facilitate the sliding of suspended matter, this corrugated plate can only fluctuate in one direction, resulting in a limited contact area, and can only rely on the bubble generator to drive the light oil to float up, but the bubble generator has poor anti-fouling and clogging performance for heavy oil and suspended matter, and is only suitable for areas with good water quality.

[0007] The metal liquid or sodium sulfate / ammonium sulfate wastewater obtained after the extraction process in the non-ferrous metallurgy and power battery recycling industries usually contains a certain amount of dispersed oil, emulsified oil or suspended oil. The presence of such oil leads to excessively high oil content in the influent or wastewater, affecting the purity and chromaticity of the salts obtained by subsequent evaporation and crystallization. If resin adsorption is directly used for oil removal, the high oil content in the influent leads to frequent resin regeneration, which increases the operating cost. This type of wastewater is usually adsorbed by activated carbon, coalescing resin, coalescing material, etc., but the adsorption capacity of activated carbon is limited, it is not easy to regenerate, and it is mostly used once, which is costly; while coalescing materials such as coalescing resins and fiber balls have high requirements for the quality of the influent water, and contain high suspended matter, oil residue, etc., which can easily cause blockage of the resin bed. Summary of the invention

[0008] To this end, an embodiment of the present invention provides a wastewater or liquid oil removal device and oil removal process, which realizes oil-water separation while solving the problem of equipment clogging. The equipment has high integration, is easy to clean, and has a significant oil removal effect.

[0009] In order to achieve the above objectives, the embodiments of the present invention provide the following technical solutions:

[0010] According to a first aspect of an embodiment of the present invention, the present invention provides a wastewater or liquid oil removal device, the device is a hollow cavity structure, including a shell and an inner cavity, the inner cavity is divided into a connected steady flow zone, a coalescence zone and a separation zone, wherein the steady flow zone and the coalescence zone are separated by a perforated plate;

[0011] The steady flow area is provided with a wastewater inlet, an elbow, a baffle and a mud collecting pocket;

[0012] The agglomeration area is provided with an egg-tray type corrugated plate and a mud collecting pocket, and the top of the convex part and the bottom of the concave part of the egg-tray type corrugated plate are respectively provided with openings;

[0013] The separation zone is provided with a light oil overflow port, a water outlet and a mud collecting pocket.

[0014] Furthermore, the shell is made of PP, PPH, stainless steel, or carbon steel with plastic lining.

[0015] Further, the elbow is in the shape of a 90° elbow, one end of which is connected to the wastewater inlet and the other end is vertically downward;

[0016] The baffle is arranged below the elbow outlet;

[0017] The steady flow area is also provided with a drug adding pipeline and / or an aeration pipeline.

[0018] Furthermore, the diameter of the top opening of the protrusion is 2mm to 2cm, and the diameter of the bottom opening of the depression is 3mm to 5cm;

[0019] The thickness of the egg tray type corrugated plate is 1 mm to 5 mm;

[0020] The inclination angle of the egg-tray type corrugated plate is 45°;

[0021] The egg tray type corrugated plate is made of oleophilic and hydrophobic materials, including PP, PPH, PE, PVDF, PVC, stainless steel, and aluminum alloy;

[0022] The surface of the egg-tray type corrugated plate is provided with an oleophilic and hydrophobic coating, the contact angle of the oleophilic and hydrophobic coating is greater than 150° C., and the thickness is 0.5 mm to 2 mm.

[0023] Furthermore, the oleophilic and hydrophobic coating is provided as follows:

[0024] (1) 100-200 parts of methyl methacrylate and 0.5-5 parts of initiator sodium persulfate and / or ammonium persulfate are mixed, the temperature is raised to 50-90° C. at a rate of 5-10° C. / min and kept at this temperature for 1-3 hours, and the temperature is lowered to 30-50° C. to obtain polymer A;

[0025] (2) mixing 1 to 5 parts of polymer A, 1 to 5 parts of dimethyldiethoxysilane, 1 to 5 parts of nano-silicon dioxide, and 5 to 50 parts of ethyl acetate to obtain a suspension B;

[0026] (3) Soak the egg-tray type corrugated sheet in the suspension B, or spray the suspension B on the surface of the egg-tray type corrugated sheet, and dry it at 40 to 60°C.

[0027] Furthermore, a plurality of the egg-tray type corrugated plates are arranged in a stacking manner, with a stacking spacing of 5 mm to 20 mm, and the top openings of the protrusions and the bottom openings of the depressions are respectively arranged on corresponding vertical lines.

[0028] Furthermore, the wastewater or liquid oil removal device is also provided with a mud discharge pump, which is connected to the mud collection pockets of the steady flow zone, the agglomeration zone and the separation zone respectively.

[0029] According to a second aspect of an embodiment of the present invention, the present invention provides an oil removal process based on the wastewater or liquid oil removal device as described in any one of the above items, characterized in that the process comprises the following steps:

[0030] (1) Oily wastewater or liquid passes through the elbow, making the fluid flow vertically downward, and at the same time touches the baffle, and large particles of sediment settle in the mud pocket to obtain a water body in the steady flow area;

[0031] (2) The water in the steady flow zone overflows through the orifice plate into the coalescence zone, and under the action of the egg-tray type corrugated plate, the light oil floats up and the heavy oil and particulate matter settles;

[0032] (3) The light oil is discharged from the light oil overflow port of the separation zone, the heavy oil and particulate matter settle in the mud collecting bag of the separation zone, and the water phase is discharged through the water outlet of the separation zone.

[0033] Furthermore, in step (2), the residence time of the water in the steady flow zone in the coagulation zone is 1 to 5 hours.

[0034] Furthermore, the pH value of the oily wastewater is 1-14.

[0035] The embodiments of the present invention have the following advantages:

[0036] 1. It can replace the gravity deoiling sedimentation tank and reduce the gravity sedimentation time.

[0037] The theoretical basis for the separation of oil droplets and particles in wastewater is the Stocks equation, as shown in equation (1):

[0038]

[0039] Among them, V set is the sedimentation velocity of the dispersed droplets, m / s; ρ l and ρh are the densities of the continuous phase and the dispersed phase, kg / m 3 ;d i is the diameter of the dispersed phase droplet, m; η is the viscosity of the continuous phase, mPa·s.

[0040] From formula (1), we can see that for a specific sewage, the viscosity and density of water are fixed, and the floating speed of oil droplets is proportional to the square of the oil droplet size. In traditional gravity sedimentation tanks, oil droplets will not coalesce, and the oil droplets are small in diameter. They need to float a long distance to reach the oil-water interface, so the sedimentation time is long. Figure 2 As shown in A.

[0041] When the egg-tray corrugated plate of the present invention is used, small oil droplets will aggregate and form an oil film when they collide with the lipophilic groups of the corrugated plate, and then form larger oil droplets. The floating speed of the enlarged oil droplets is significantly accelerated, and they quickly reach the oil-water interface through the oil holes in the vertical direction (i.e., the openings on the top of the egg-tray corrugated plate), thereby realizing efficient separation of the oil-water two phases. After solid particles or heavy oil particles collide with the surface of the corrugated plate, they will be deposited on the surface of the corrugated plate due to the blocking effect of the corrugated plate. The corrugated plate is inclined at a 45° angle, which is conducive to the sliding of the particles, so that they are discharged from the sand mouth (i.e., the openings on the bottom of the egg-tray corrugated plate), thereby realizing the separation of solid particles, such as Figure 2 As shown in B.

[0042] 2. In the prior art, if the oil content in the wastewater or feed liquid is too high, it needs to be subjected to demulsification-flocculation treatment before entering the biochemical pool, which increases the treatment cost and the amount of sludge. The wastewater or feed liquid deoiling device of the present invention can replace the flotation deoiling tank, reduce the residence time of the flotation tank, and improve the oil-water separation efficiency.

[0043] 3. The present invention can simultaneously remove heavy oil, light oil and suspended solids, and treat them by physical methods, which greatly reduces the treatment cost and alleviates the fouling problem of the deacidification tower, deammoniation tower and extraction tower in the subsequent treatment of semi-coke wastewater.

[0044] 4. For wastewater from nonferrous metallurgical industry, it can be used as a pre-oil removal equipment to replace activated carbon. It has a large processing capacity and does not require additional oil-water separation devices. Compared with agglomeration oil removal materials, fiber balls, etc., it has strong anti-fouling and clogging performance and lower requirements for influent water quality.

[0045] 5. Conventional corrugated plates have a long slope and no sand discharge ports. When there is a high content of solids and heavy oil, the corrugated plates are prone to clogging.

[0046] 6. The device of the present invention has a high degree of integration. The steady flow zone, the aggregation zone, and the separation zone are integrated on one device, which occupies a smaller area. At the same time, the device is easy to operate and has a good application prospect. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the implementation methods of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the implementation methods or the description of the prior art. Obviously, the drawings in the following description are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0048] The structures, proportions, sizes, etc. illustrated in this specification are only used to match the contents disclosed in the specification so as to facilitate understanding and reading by persons familiar with the technology. They are not used to limit the conditions under which the present invention can be implemented, and therefore have no substantial technical significance. Any structural modification, change in proportion or adjustment of size shall still fall within the scope of the technical contents disclosed in the present invention without affecting the effects and purposes that can be achieved by the present invention.

[0049] Figure 1 A schematic diagram of the structure of the wastewater or liquid oil removal device provided by the present invention;

[0050] Figure 2 The conventional gravity settling and corrugated plate agglomeration provided by the present invention are compared;

[0051] Figure 3 A structural diagram of an egg-tray type corrugated plate provided by the present invention, wherein A is a schematic diagram and B is a real diagram;

[0052] Figure 4 The stacking structure diagram of the egg tray type corrugated plate provided by the present invention, wherein A is a schematic diagram and B is a real picture;

[0053] Figure 5 The oil removal process flow chart provided by the present invention;

[0054] Figure 6 The oil removal rate and suspended solids removal rate of the pyrolysis water provided in Example 1 of the present invention;

[0055] Figure 7 A comparison diagram of water inlet and outlet effects provided in Example 1 of the present invention, left: water inlet; right: water outlet;

[0056] Figure 8 The oil removal rate and suspended solids removal rate of the pyrolysis water provided in Example 2 of the present invention;

[0057] Fig. 9 A comparison diagram of water inlet and outlet effects provided in Example 2 of the present invention, left: water inlet; right: water outlet;

[0058] Fig.10 The oil removal rate and suspended solids removal rate of the ternary ammonium sulfate liquid provided in Example 3 of the present invention;

[0059] Fig.11 A comparison diagram of water inlet and outlet effects provided in Example 3 of the present invention, left: water inlet; right: water outlet;

[0060] In the figure: 1: dosing pipeline; 2: pipeline mixer; 3: orifice plate; 4: egg-tray corrugated plate; 4-1: oil hole; 4-2: sand hole; 5: exhaust port; 6: oil collecting tank; 7: light oil overflow port; 8: water outlet; 9: water outlet pipeline; 10: mud collecting bag in separation area; 11: mud discharge pump; 12: fixing rod; 13: mud discharge pipe; 14: aeration pipe; 15: baffle; 16: mud collecting bag in steady flow area; 17: mud collecting bag in agglomeration area. DETAILED DESCRIPTION

[0061] The following is a description of the implementation of the present invention by specific embodiments. People familiar with the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. 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.

[0062] See also Figure 1 The present invention provides a wastewater or liquid oil removal device, which has a hollow cavity structure, including a shell and an inner cavity. The shell is made of PP, PPH, stainless steel, or carbon steel lining plastic. The inner cavity is divided into three interconnected areas, namely, a steady flow area, a coalescence area, and a separation area, wherein the steady flow area and the coalescence area are separated by a perforated plate.

[0063] Steady flow area: equipped with wastewater inlet, dosing pipeline 1, pipeline mixer 2, elbow, baffle 15 and steady flow area mud pocket 16. Among them, the elbow adopts a 90° elbow, one end of which is connected to the wastewater inlet pipeline and the other end is vertically downward. The baffle 15 is arranged below the elbow outlet, and the steady flow area mud pocket is located at the bottom of the steady flow area. A drainage hole is arranged at the bottom of the mud pocket. The oily wastewater enters the steady flow area and changes the flow direction of the water body through the elbow to vertically downward. At the same time, it touches the baffle 15, which slows down the influence of the inlet flow velocity on the overall fluctuation. At the same time, more large particles of sediment and the like settle in the steady flow area, and the particles collected in the steady flow area mud pocket are discharged through the drainage hole. The steady flow area is separated from the coalescence area by a perforated plate 3. In some preferred embodiments, the perforated plate 3 is a stainless steel plate, wherein one or more holes are arranged at the upper position, and the size of the hole is 3mm to 30mm. The water in the steady flow area flows into the coalescence area through the holes of the orifice plate 3 in an overflow manner, which can reduce the turbulence of the water flow and allow the water to enter the coalescence area more smoothly without disturbing the process of oil pollution coalescence and separation.

[0064] In some preferred embodiments, the demulsifier is mixed with the oily wastewater through the dosing pipe 1. The demulsifier is a conventional agent used in sewage treatment, such as polyether demulsifiers, quaternary ammonium salt demulsifiers, amine demulsifiers, etc. In some preferred embodiments, an aeration pipeline is provided in the steady flow area. The aeration pipeline is a PP pipe with holes, the hole size is 1 to 10 mm, and the spacing between the two holes can be selected as 1 to 20 cm according to the size of the equipment. It is used to pass oxygen, ozone, nitrogen, carbon dioxide and other gases, and plays an oxidation or stirring role. The aeration pipeline can be arranged in a "Y" type, "O" type, triangle, square, "mountain" type, etc.

[0065] Agglomeration area: egg tray type corrugated plate is installed inside. The structure of egg tray type corrugated plate is shown in Figure 3 The top of the convex part and the bottom of the concave part are respectively provided with openings, the top opening of the convex part is an oil hole 4-1, and the bottom opening of the concave part is a sand hole 4-2. The egg-tray type corrugated plate is used to float and settle small oil droplets (light oil), heavy oil and particulate matter in the water body of the steady flow area. The lower surface of the egg-tray type corrugated plate is used for the aggregation and growth of small oil droplets, and the upper surface is used for the sedimentation of heavy oil and particulate matter. The top oil holes are conducive to the floating of the oil droplets after growth, and the bottom sand holes are conducive to the sedimentation of heavy oil and particulate matter. The bottom of the agglomeration area is provided with a coalescence area mud collecting bag 17 and a sewage outlet for the collection and discharge of heavy oil pollution and suspended particulate matter.

[0066] In some preferred embodiments, the inclination angle of the egg tray corrugated plate is 45° (see Figure 4 ), which is conducive to the floating of oil droplets and the sinking of heavy oil particles. The diameter of the oil hole is 2mm~2cm, the diameter of the sand hole is 3mm~5cm, and the thickness of the egg-tray corrugated plate is 1mm~5mm.

[0067] The egg-tray corrugated plate has oleophilic and hydrophobic properties, and its materials include PP, PPH, PE, PVDF, PVC, stainless steel, and aluminum alloy. An oleophilic and hydrophobic coating is arranged on the surface of the egg-tray corrugated plate, and the thickness is 0.5mm to 2mm.

[0068] The method for setting the oleophilic and hydrophobic coating comprises the following steps:

[0069] (1) 100-200 parts of methyl methacrylate and 0.5-5 parts of an initiator (persulfate, such as sodium persulfate and / or ammonium persulfate) are mixed, the temperature is raised to 50-90° C. at a rate of 5-10° C. / min and kept at this temperature for 1-3 hours, and then the temperature is lowered to 30-50° C. to obtain a polymer A;

[0070] (2) mixing 1 to 5 parts of polymer A, 1 to 5 parts of dimethyldiethoxysilane, 1 to 5 parts of nano-silicon dioxide, and 5 to 50 parts of ethyl acetate to obtain a suspension B;

[0071] (3) After soaking the egg-tray type corrugated sheet in the suspension B for 1 to 2 hours, the sheet is dried at 40 to 60° C., or the suspension B is sprayed onto the surface of the egg-tray type corrugated sheet and the sheet is dried at 40 to 60° C.

[0072] After testing, the contact angle of the oleophilic and hydrophobic coating obtained by the above method is >150°C, and it is also wear-resistant, corrosion-resistant, and has strong antioxidant capacity. The study found that the egg-tray-type corrugated plate with the above coating is more conducive to the separation of oil and water, especially for the separation of heavy oil, light oil and suspended matter in the pyrolysis wastewater of the semi-coke industry.

[0073] In some preferred embodiments, in order to improve the degreasing effect, multiple egg tray type corrugated plates are used by stacking, see Figure 4 A is a diagram of the stacking structure of multiple egg-tray corrugated plates, and B is a real (side) diagram. The stacking spacing is 5mm to 20mm. Egg-tray corrugated plates can be designed into regular squares or rectangles. According to the requirements of oil removal, multiple groups can be stacked and used in parallel. The paralleling method can be horizontal or vertical.

[0074] After running for a certain period of time, a high-pressure spray gun can be inserted into the sand holes of the egg-tray corrugated plate and the egg-tray corrugated plate can be cleaned with clean water. For special difficult-to-clean dirt blockages, the egg-tray corrugated plate can also be soaked and cleaned with hot water, liquid alkali, and hot steam, or a combination of two. The cleaning time is 0.5 to 5 hours.

[0075] Among them, the cleaning method can be in-situ cleaning, or the egg-tray corrugated plate can be removed and scrubbed. Since the egg-tray corrugated plate is stacked, it does not need additional fixing, is easy to disassemble, and has strong anti-fouling and blocking performance. It is especially suitable for heavy oil pollution such as coal tar suspended particles in the complex wastewater of the semi-coke coking industry. For special difficult-to-clean fouling, the hot water temperature used in the cleaning process is 30-100℃; the liquid alkali concentration is 1%-30%, the liquid alkali temperature is 30-90℃; the hot steam temperature is 100-120℃.

[0076] Separation zone: mainly separates the grown light oil droplets and heavy oil particles from the water phase that flow through the agglomeration zone. The light oil on the top is stored in the oil collecting tank 6 (if it has utilization value, it can be recycled and purified) and further discharged through the light oil overflow port 7. The heavy oil and silt are discharged from the separation zone mud collecting bag 10 located at the bottom of the separation zone, and the treated water is discharged through the outlet 8 via the outlet pipe 9.

[0077] In some preferred embodiments, the water outlet pipe 9 adopts a 90° elbow, and the overflow is discharged externally. The vertical part of the elbow is inside the separation zone, and the horizontal part extends out of the box.

[0078] In some preferred embodiments, for industrial wastewater such as blue coke, which contains both heavy oil pollution and suspended particles and light oil, the inlet of the vertical part of the outlet pipe is set in the middle of the entire height of the separation zone. For water bodies mainly containing light oil, it is set below the middle.

[0079] For the coke coking wastewater, the wastewater or liquid oil removal device of the present invention can replace the gravity oil removal tank to reduce the sedimentation time. It can also add demulsifiers through the pipeline mixer in the steady flow area and then enter the agglomeration area, which can replace the flotation device, reduce the residence time of the flotation tank, and solve the problem of liquid or foam overflow caused by the aeration stage.

[0080] For the wastewater from the lignite industry, after being treated by the wastewater or liquid oil removal device of the present invention, its suspended matter and oil content are significantly reduced, and most of the heavy oil particles are separated, and can be connected with the agglomeration resin for secondary oil removal. On the one hand, the oil removal rate is improved, and on the other hand, the combination of the two can avoid the agglomeration resin being contaminated by heavy oil particles and causing compaction failure.

[0081] Example 1

[0082] This embodiment provides an oil removal process based on a wastewater or liquid oil removal device, comprising the following steps:

[0083] (1) The pyrolysis wastewater of a semi-coke enterprise is dark brown or black oily wastewater, with an oil content of 4000-9000 mg / L and suspended solids of 400-1000 mg / L. It is pumped into the pipeline mixer 2 by a centrifugal pump, and the fluid direction is changed through a 90° elbow, entering downward, and contacting the inclined plate to be pumped into the steady flow area. The heavy oil pollution such as silt in the water body first settles into the mud collecting bag 16 in the steady flow area as a preliminary separation.

[0084] (2) The water in the steady flow zone flows uniformly through the orifice plate 3 into the coalescence zone and flows through the egg tray corrugated plate 4, where light oil and heavy oil suspended particles are coalesced and separated. Among them, the diameter of the top opening of the egg tray corrugated plate at the convex part is 1 cm, and the diameter of the bottom opening of the concave part is 2 cm; the egg tray corrugated plate is based on PP plastic with a thickness of 2 mm and a 0.5 mm thick oleophilic and hydrophobic coating is provided on the surface, and the inclination angle is 45°; multiple egg tray corrugated plates are arranged in a stacking manner, with a stacking spacing of 10 mm, and the top opening of the convex part and the bottom opening of the concave part are respectively arranged on the corresponding vertical straight line. The residence time of the water in the coalescence zone is 2 hours. The volatile organic gas generated in the coalescence zone is discharged or treated in an organized manner through the exhaust port 5, and some heavy oil pollution and suspended particles enter the coalescence zone mud collection bag 17 at the bottom, and the sludge pump 11 is turned on regularly to discharge.

[0085] Among them, the setting method of the oleophilic and hydrophobic coating is as follows:

[0086] S1. Mix 100 parts of methyl methacrylate and 2 parts of sodium persulfate, heat to 80°C at a rate of 5°C / min and keep warm for 3 hours, then cool to 40°C to obtain polymer A;

[0087] S2, mix 3 parts of polymer A with 5 parts of dimethyldioxyhexylsilane, 2 parts of nano-silicon dioxide and 15 parts of ethyl acetate to obtain suspension B;

[0088] S3. Soak the PP substrate after purification and decontamination in suspension B. After 2 hours, dry it at 60° C. to evaporate the solvent.

[0089] (3) After entering the separation zone, the upper floating oil enters the oil collecting tank 6 and accumulates, and then is discharged through the light oil overflow port 7. The heavy oil and suspended particles enter the mud collecting bag 10 at the bottom of the separation zone, and the sludge pump 11 is turned on regularly to discharge. The treated water is discharged through the outlet 8 of the outlet pipe 9 and enters the subsequent process section for subsequent treatment.

[0090] After 270 hours of continuous operation, the results are as follows: Figure 6 As shown in the figure, the oil removal rate fluctuates between 30% and 55%, and the suspended solids removal rate fluctuates between 50% and 75%. Figure 7 ,Depend on Figure 7 It can be seen that the outlet water has changed from a dark brown opaque liquid to a reddish brown transparent liquid compared to the inlet water. Visually, it can also be seen that there is an obvious effect of removing oil and suspended solids.

[0091] Example 2

[0092] This embodiment provides an oil removal process based on a wastewater or liquid oil removal device, comprising the following steps:

[0093] (1) After gravity oil removal and addition of flotation agent, the pyrolysis wastewater of a semi-coke enterprise has an oil content of 4000-6000 mg / L and a suspended solids content of 100-600 mg / L. It is pumped into the pipeline mixer through a centrifugal pump, passes through a 90° elbow, changes the flow direction, enters downward, and contacts the inclined plate and is pumped into the steady flow area. The heavy oil pollution such as silt in the water body first settles into the mud collecting bag 16 in the steady flow area as a preliminary separation.

[0094] (2) The water in the steady flow zone is evenly dispersed through the orifice plate 3 and enters the coalescence zone, and flows through the egg tray corrugated plate 4, where light oil and heavy oil suspended particles are coalesced and separated. Among them, the diameter of the top opening of the egg tray corrugated plate at the convex part is 5mm, and the diameter of the bottom opening at the concave part is 2cm; the egg tray corrugated plate is based on stainless steel with a thickness of 3mm and a 1mm thick oleophilic and hydrophobic coating is provided on the surface, and the inclination angle is 45°; multiple egg tray corrugated plates are arranged in a stacking manner, with a stacking spacing of 15mm, and the top opening of the convex part and the bottom opening of the concave part are respectively arranged on the corresponding vertical lines. The residence time of the water body in the coalescence zone is 1h. The volatile organic gas generated in the coalescence zone is discharged or treated in an organized manner through the exhaust port 5, and some heavy oil pollution and suspended particles enter the coalescence zone mud collection bag 17 located at the bottom, and the sludge pump 11 is turned on regularly to discharge.

[0095] Among them, the setting method of the oleophilic and hydrophobic coating is as follows:

[0096] S1. Mix 200 parts of methyl methacrylate and 5 parts of ammonium persulfate, heat to 80°C at a rate of 5°C / min and keep warm for 3 hours, then cool to 45°C to obtain polymer A;

[0097] S2, mix 5 parts of polymer A with 3 parts of dimethyldioxyhexylsilane, 5 parts of nano-silicon dioxide and 50 parts of ethyl acetate to obtain suspension B;

[0098] S3. Soak the stainless steel after purification and decontamination in suspension B. After 1 hour, dry it at 40°C to evaporate the solvent.

[0099] (3) After entering the separation zone, the upper floating oil enters the oil collecting tank 6 and accumulates, and then is discharged through the light oil overflow port 7. The heavy oil and suspended particles enter the mud collecting bag 10 at the bottom of the separation zone, and the sludge pump 11 is turned on regularly to discharge. The treated water is discharged through the outlet 8 of the outlet pipe 9 and enters the subsequent process section for subsequent treatment.

[0100] After 72 hours of continuous operation, the results are as follows: Figure 8 As shown in the figure, the oil removal rate fluctuates between 50% and 90%, and the suspended solids removal rate fluctuates between 70% and 90%. Fig. 9 ,Depend on Fig. 9 It can be seen that the influent color is brown-yellow opaque liquid. After treatment, it becomes yellow transparent liquid. Visually, it has obvious oil and suspended solids removal effects.

[0101] Example 3

[0102] This embodiment provides an oil removal process based on a wastewater or liquid oil removal device, comprising the following steps:

[0103] The ammonium sulfate oily wastewater from a certain ternary industry was treated using the method of Example 1.

[0104] Continuous operation for 168 hours, the operating effect is shown in Fig.10 , the inlet oil content is 520~940mg / L, the outlet oil content is 397~460mg / L, the inlet and outlet comparison chart is shown in Fig.11 The inlet water is a yellow turbid liquid, and the outlet water is almost colorless and slightly turbid. Visually, there is an obvious oil removal effect.

[0105] Although the present invention has been described in detail above by general description and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements can be made to the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all belong to the scope of protection claimed by the present invention.

Claims

1. A wastewater or liquid oil removal device, characterized in that: The device has a hollow cavity structure, including a shell and an inner cavity, wherein the inner cavity is divided into a steady flow zone, a coalescence zone and a separation zone which are connected, wherein the steady flow zone and the coalescence zone are separated by a perforated plate; The steady flow area is provided with a wastewater inlet, an elbow, a baffle and a mud collecting pocket; The agglomeration area is provided with an egg-tray type corrugated plate and a mud collecting pocket, and the top of the convex part and the bottom of the concave part of the egg-tray type corrugated plate are respectively provided with openings; The separation zone is provided with a light oil overflow port, a water outlet and a mud collecting pocket.

2. The wastewater or liquid oil removal device according to claim 1, characterized in that: The shell is made of PP, PPH, stainless steel, or carbon steel with plastic lining.

3. The wastewater or liquid oil removal device according to claim 1, characterized in that: The elbow is in the shape of a 90° elbow, one end of which is connected to the wastewater inlet and the other end of which is vertically downward; The baffle is arranged below the elbow outlet; The steady flow area is also provided with a drug adding pipeline and / or an aeration pipeline.

4. The wastewater or liquid oil removal device according to claim 1, characterized in that: The diameter of the top opening of the protrusion is 2mm to 2cm, and the diameter of the bottom opening of the depression is 3mm to 5cm; The thickness of the egg tray type corrugated plate is 1 mm to 5 mm; The inclination angle of the egg-tray type corrugated plate is 45°; The egg tray type corrugated plate is made of oleophilic and hydrophobic materials, including PP, PPH, PE, PVDF, PVC, stainless steel, and aluminum alloy; The surface of the egg-tray type corrugated plate is provided with an oleophilic and hydrophobic coating, the contact angle of the oleophilic and hydrophobic coating is greater than 150° C., and the thickness is 0.5 mm to 2 mm.

5. The wastewater or liquid oil removal device according to claim 4, characterized in that: The method for setting the oleophilic and hydrophobic coating is as follows: (1) 100-200 parts of methyl methacrylate and 0.5-5 parts of initiator sodium persulfate and / or ammonium persulfate are mixed, the temperature is raised to 50-90° C. at a rate of 5-10° C. / min and kept at this temperature for 1-3 hours, and the temperature is lowered to 30-50° C. to obtain polymer A; (2) mixing 1 to 5 parts of polymer A, 1 to 5 parts of dimethyldiethoxysilane, 1 to 5 parts of nano-silicon dioxide, and 5 to 50 parts of ethyl acetate to obtain a suspension B; (3) Soak the egg-tray type corrugated sheet in the suspension B, or spray the suspension B on the surface of the egg-tray type corrugated sheet, and dry it at 40 to 60°C.

6. The wastewater or liquid oil removal device according to claim 1, characterized in that: A plurality of the egg-tray type corrugated plates are arranged in a stacking manner, with a stacking spacing of 5 mm to 20 mm, and the top openings of the protrusions and the bottom openings of the depressions are respectively arranged on corresponding vertical lines.

7. The wastewater or liquid oil removal device according to claim 1, characterized in that: The wastewater or liquid oil removal device is also provided with a mud discharge pump, which is respectively connected to the mud collection pockets in the steady flow zone, the agglomeration zone and the separation zone.

8. An oil removal process based on the wastewater or liquid oil removal device according to any one of claims 1 to 7, characterized in that: The process comprises the following steps: (1) Oily wastewater or liquid passes through the elbow, making the fluid flow vertically downward, and at the same time touches the baffle, and large particles of sediment settle in the mud pocket to obtain a water body in the steady flow area; (2) The water in the steady flow zone overflows through the orifice plate into the coalescence zone, and under the action of the egg-tray type corrugated plate, the light oil floats up and the heavy oil and particulate matter settles; (3) The light oil is discharged from the light oil overflow port of the separation zone, the heavy oil and particulate matter settle in the mud collecting bag of the separation zone, and the water phase is discharged through the water outlet of the separation zone.

9. The oil removal process according to claim 8, characterized in that: In step (2), the residence time of the water in the steady flow zone in the coagulation zone is 1 to 5 hours.

10. The oil removal process according to claim 8, characterized in that: The pH value of the oily wastewater is 1-14.

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