Catering industry wastewater oil removal treatment method
Technical Field
The invention relates to a method for removing oil from restaurant wastewater, and belongs to the field of wastewater treatment in environmental protection.
Background
Among domestic sewage, restaurant oily sewage is one of the main water bodies. A large amount of sewage containing a large amount of animal and vegetable oil is discharged in daily life of numerous restaurants, dining halls, food processing enterprises and residents, and if the sewage is not treated directly, the sewage can cause the blockage of pipelines, the turbidity and the putrefaction of water and the breeding of disease sources.
At present, the existing oil removing method for restaurant sewage comprises the following four methods.
(1) The physical method mainly comprises a filtration separation method and an air flotation separation method, but the physical method is only suitable for separating oil products with larger particles in the wastewater, the treatment efficiency is 60-80%, and the oil content in the effluent is about 100-200 mg/L. The fine oil droplets and emulsified oil in the wastewater are difficult to remove.
(2) The chemical method has the advantages of low equipment cost, good treatment effect and simple operation; the disadvantages are the need to continuously put chemical agents into the waste water, the high operating cost and the introduction of secondary pollution.
(3) The physical and chemical methods mainly comprise an air floatation method, an adsorption method, an electrochemical method, an ultrasonic separation method and the like, and generally have the advantages of strong adaptability and wide selectivity.
(4) The biochemical treatment method is to decompose complex organic matters into simple substances by utilizing the biochemical action of microorganisms, thereby converting toxic substances into non-toxic substances and purifying the oily sewage. The microorganism can use organic matter as nutrient substance, so that a part of the organic matter can be absorbed and converted into organic components in the microorganism body or proliferated into new microorganism, and the rest can be oxidized and decomposed into simple organic or inorganic matter by the microorganism.
Because the traditional treatment methods all have certain defects, the existing treatment technical route is needed to be got rid of, a new way for treating domestic sewage to remove oil is developed, and a brand new domestic sewage oil removal treatment technology is developed.
Disclosure of Invention
In order to solve the defects in the prior art, the invention provides a method for removing oil from restaurant wastewater, the restaurant wastewater enters a buffer pool through a wastewater pipeline, centralized collection and stabilization are carried out at the buffer pool, an outlet of the buffer pool is connected with a coarse grid through the wastewater pipeline, large-diameter solid matters in the restaurant wastewater are removed at the buffer pool, an outlet of the coarse grid is connected with a micro-bubble oil adsorption device through the wastewater pipeline, 9 ultra-fine bubble generators are arranged at the bottom of the micro-bubble oil adsorption device, a transversely placed pi-allyl nickel compound modified diatomite adsorption film can be accommodated above the liquid level of the device, a water inlet valve is arranged at the upper part of the left side of the device, a water outlet valve is arranged at the bottom of the right side of the device, the restaurant wastewater containing oil and primarily removing large-particle-diameter matters through the coarse grid enters the interior of the device through the water inlet valve at the, the device generates ultra-fine bubbles with the diameter less than 50 microns, the ultra-fine bubbles can carry oil molecules in the wastewater to float upwards together and enable the oil molecules to be adsorbed by a pi-allylnickel-containing compound modified diatomite adsorption film on the liquid surface, the right side wall of the device is connected with a high-temperature oil catalytic reforming desorption reactor, so that an aerogel felt heat-insulating layer is attached to the right side wall of the device, and a stainless steel mechanical arm and a ball-rotating bearing are arranged at the top end of the aerogel felt heat-insulating layer; the oil catalytic reforming desorption reactor is made of high-strength stainless steel, 5 electric heating blast fans are arranged at the bottom of the oil catalytic reforming desorption reactor, a set of stainless steel membrane frame is arranged in the oil catalytic reforming desorption reactor, 5 pi-allyl nickel compound modified diatomite adsorption membranes to be subjected to high-temperature treatment can be vertically placed on the membrane frame, and a heavy oil outlet is formed in the right side of the bottom of the oil catalytic reforming desorption reactor; the method comprises the following steps that a modified diatomite adsorption film containing pi-allylnickel compounds and completely adsorbing oil is grabbed by a stainless steel mechanical arm and is vertically placed on a stainless steel film frame in an oil catalytic heavy desorption reactor, 5 electric heating air blower fans at the bottom of the reactor start to work to generate high-temperature air at 200-250 ℃, under the catalysis of pi-allylnickel compounds, C-H bonds in oil molecules can be broken and rapidly combined into C-C bonds, and the C-C bonds can not be broken again, so that the oil molecules with short carbon chains can be gradually synthesized into heavy oil molecules with long carbon chains, and meanwhile, the heavy oil molecules can be desorbed from the modified diatomite adsorption film containing the pi-allylnickel compounds at high temperature and are discharged from a heavy oil outlet on the right side of the bottom of the reactor after being converged, and can be collected and reused in a centralized manner; the outlet of the micro-bubble air-floating oil adsorption device is connected with a pH value adjusting tank through a waste water pipeline, the pH value of the waste water is adjusted to be nearly neutral, the outlet of the pH value adjusting tank is connected with a primary sedimentation tank 6 through a waste water pipeline, the waste water is settled and clarified, the outlet of the primary sedimentation tank is connected with an organic rhodium catalytic reaction tank through a waste water pipeline, the outer layer of the organic rhodium catalytic polymerization reaction tank is wrapped by a tank body insulating protective layer, the right upper part of the reaction tank is provided with a water inlet valve, the left lower part of the reaction tank is provided with a water outlet valve, the central part of the tank body is provided with dichlorotetracarbonyl bis rhodium porous filler which is used as a polymerization reaction catalyst, the lower part of the filler layer is connected with a particulate matter discharge port, the right and left side wall plates are respectively provided with a high-pressure discharge electrode, the left and right sides of the bottom of, the high-voltage discharge electrodes perform high-voltage discharge once every 0.2s to generate a high-voltage electric arc, high energy generated by the high-voltage electric arc is absorbed by residual grease in the wastewater, C-H bonds in grease molecules are excited by energy to be in an unstable state, and are broken and recombined under the catalytic action of dichlorotetracarbonyl dirhodium, macromolecular polymerized particles are finally generated and are dispersed in the water in the form of suspended matters, and are discharged out of the reaction tank through a water outlet valve on the right side of the reaction tank to enter a secondary sedimentation tank, residual insoluble substances in the wastewater are completely removed, an outlet of the secondary sedimentation tank is connected with a water purification tank through a wastewater pipeline, and an outlet of the water purification tank discharges the purified effluent after treatment through the wastewater pipeline.
The effective volume of the micro-bubble air-float oil adsorption device is 155m3The superfine bubble generator can generate superfine bubbles with the diameter less than 50 μm, the normal working voltage is 20V, and the working life is generally 5000 h.
The volume of the oil catalytic reforming desorption reactor is 330m3The electric heating blower can generate hot air at 200-250 ℃, and the normal working voltage is 380V.
The area of the pi-allyl nickel compound modified diatomite adsorption film is 10.2m2The content of the pi-allylnickel compound was 16.6g/m2The purity of the pi-allylnickel compound was 95.2%.
The invention has the advantages that:
(1) the method gets rid of the existing restaurant wastewater oil purification treatment mode, creatively adopts a technical route combining physical means and a chemical method, fully utilizes the adsorption effect of the modified diatomite and the catalytic synthesis effect of the pi-allyl nickel compound, so that the oil in the restaurant wastewater is adsorbed and enriched and undergoes a synthesis reaction to generate usable heavy oil, and the removal efficiency of the oil reaches 99.8 percent.
(2) The invention utilizes hot air as a heating source and adopts a mode of dispersing the pi-allyl nickel compound in the modified diatomite, so that the synthetic reaction is more completely carried out, the reaction efficiency is improved, and the processing capacity of the whole system is improved.
(3) The modified diatomite adsorption film used in the invention is regenerated after the thermal desorption process, and can be reused for adsorbing oil in wastewater, thereby realizing the reutilization of materials and greatly reducing the operation cost.
(4) The invention has the advantages of simple and easy principle, lower design and construction cost, better treatment effect and low operation and maintenance cost, and is beneficial to large-scale popularization and application.
Drawings
FIG. 1 is a schematic diagram of the apparatus of the present invention.
In the figure: 1-a buffer tank, 2-a coarse grid, 3-a microbubble air-floating oil adsorption device, 4-an oil catalytic reforming desorption reactor, 5-a pH value adjusting tank, 6-a primary sedimentation tank, 7-an organic rhodium catalytic reaction tank, 8-a secondary sedimentation tank and 9-a water purification tank;
FIG. 2 is a schematic diagram of a micro-bubble air-flotation oil adsorption device and an oil catalytic reforming desorption reactor.
32-a superfine bubble generator, 33-superfine bubbles, 34-a stainless steel mechanical arm, 35-a ball rotating bearing, 36-a water inlet valve and 37-a water outlet valve; 41-aerogel felt thermal insulation layer, 42-pi-allyl nickel compound modified diatomite adsorption film, 43-stainless steel film frame, 44-electric heating blower fan and 45-heavy oil outlet.
FIG. 3 is a schematic diagram of a high-pressure discharge organorhodium catalytic polymerization reactor.
71-high-voltage discharge electrode, 72-dichlorotetracarbonyldirhodium porous filler, 73-tank body insulating protective layer, 74-water inlet valve, 75-water outlet valve, 76-stirring paddle and 77-particle discharge port.
Detailed Description
As shown in figure 1, restaurant wastewater oil removal treatment method, oily restaurant wastewater enters a buffer tank 1 through a wastewater pipeline, centralized collection and preliminary stable adjustment are carried out, an outlet of the buffer tank 1 is connected with a coarse grating 2 through a wastewater pipeline, large-diameter solid matters in the restaurant wastewater are removed, an outlet of the coarse grating 2 is connected with a micro-bubble oil adsorption device 3 through a wastewater pipeline, a pi-allyl nickel compound-containing modified diatomite adsorption membrane 42 in the micro-bubble oil adsorption device 3 can be grabbed by a stainless steel mechanical arm 34 after oil is completely adsorbed, the membrane is sent to an oil catalytic reforming desorption reactor 4, heavy oil generated in the oil catalytic reforming desorption reactor 4 is discharged from a heavy oil outlet 45 and recycled, meanwhile, an outlet of the micro-bubble oil adsorption device 3 is connected with a pH value adjusting tank 5 through a wastewater pipeline, the pH value of the wastewater is adjusted to be nearly neutral, the outlet of the pH value adjusting tank 6 is connected with a primary sedimentation tank 6 through a waste water pipeline, the waste water is settled and clarified, and the outlet of the primary sedimentation tank 6 is connected with an organic rhodium catalytic reaction tank through a waste water pipeline7, polymerizing residual grease in the sewage into water-insoluble particles through high-voltage discharge catalysis, connecting the particles to a secondary sedimentation tank 8 through a wastewater pipeline, completely removing residual insoluble substances in the wastewater, connecting an outlet of the secondary sedimentation tank 8 to a water purification tank 9 through a wastewater pipeline, and discharging the treated purified effluent through a wastewater pipeline from an outlet of the water purification tank 9; wherein, the microbubble air-float oil adsorption device 3 is made of high-strength glass fiber reinforced plastic, and the effective volume is 155m39 superfine bubble generators 32 are arranged at the bottom of the device and can generate superfine bubbles 33 with the diameter less than 50 mu m, a transversely placed pi-allyl nickel compound modified diatomite adsorption film 42 with the area of 10.2m can be accommodated above the liquid level of the device2The content of the pi-allylnickel compound was 16.6g/m2The purity of the pi-allyl nickel compound is 95.2 percent, a water inlet valve 36 is arranged at the upper part of the left side of the device, a water outlet valve 37 is arranged at the bottom of the right side of the device, the right side wall of the device is connected with a high-temperature oil catalytic reforming desorption reactor 4, so an aerogel felt heat-insulating layer 41 is attached to the right side wall of the device, and a stainless steel mechanical arm 34 and a ball rotating bearing 35 are arranged at the top end of the aerogel felt heat-insulating layer 41; wherein, the oil catalytic reforming desorption reactor 4 is made of high-strength stainless steel and has a volume of 330m3The bottom of the device is provided with 5 electric heating blast fans 44 which can generate hot air at the temperature of 200-250 ℃, a set of stainless steel membrane frame 43 is arranged in the device, 5 pi-allyl nickel compound modified diatomite adsorption membranes 42 to be subjected to high-temperature treatment can be vertically placed on the membrane frame, and the right side of the bottom of the device is provided with a heavy oil outlet 45; restaurant wastewater containing oil and primarily removing large-particle-size substances through a coarse grating 2 enters the interior of a microbubble air-floating oil adsorption device 3 through a water inlet valve 36 at the upper left part of the device, 9 ultrafine bubble generators 32 start to work to generate ultrafine bubbles 33 with the diameter smaller than 50 microns, the ultrafine bubbles 33 can carry oil molecules in the wastewater to float upwards together and be adsorbed by a pi-allyl nickel compound-containing modified diatomite adsorption film 42 above the liquid surface, the pi-allyl nickel compound-containing modified diatomite adsorption film 42 which completely adsorbs the oil is grabbed by a stainless steel mechanical arm 34 and is vertically placed on a stainless steel film frame 43 in an oil catalytic heavy desorption reactor 4, 5 parts of electrothermal blowing fans 44 at the bottom of the reactor start to work to produce oilGenerating high-temperature air at 200-250 ℃, and under the catalysis of the pi-allyl nickel compound, the C-H bonds in oil molecules can be broken briefly and quickly recombined to form C-C bonds or C-H bonds, the C-H bonds can be broken again, and the C-C bonds can not be broken again due to the limited catalytic action of the pi-allyl nickel compound, so that the oil molecules with short carbon chains can be gradually synthesized into heavy oil molecules with long carbon chains. Meanwhile, heavy oil molecules are desorbed from the pi-allyl nickel compound-containing modified diatomite adsorption film 42 at high temperature, and are discharged from a heavy oil discharge port 45 on the right side of the bottom of the reactor after being converged, so that the heavy oil molecules can be collected and reused in a centralized manner. The outer layer of the high-voltage discharge organic rhodium catalytic polymerization reaction tank 7 is wrapped by a tank body insulating protective layer 73, the inner part of the high-voltage discharge organic rhodium catalytic polymerization reaction tank is of a silicon carbide ceramic structure, and the effective volume of the reaction tank is 133m3The right upper part of the reaction tank is provided with a water inlet valve 74, the left lower part is provided with a water outlet valve 75, the central part of the tank body is provided with a dichlorotetracarbonyldirhodium porous filler 72 serving as a polymerization reaction catalyst, the pore diameter of the filler is 5.2mm, and the specific surface area is 6.5cm2The lower part of the packing layer is connected with a particle discharge port 77, a high-voltage discharge electrode 71 is respectively arranged in the right middle of the left side wall plate and the right side wall plate, a stirring paddle 76 is respectively arranged on the left side and the right side of the bottom of the reaction tank, sewage enters the reaction tank through a water inlet valve 74 of a high-voltage discharge organic rhodium catalytic polymerization reaction tank 7, the high-voltage discharge electrodes 71 carry out high-voltage discharge once at an interval of 0.1s, the discharge voltage range is 8500-15000V, a high-voltage electric arc which traverses the left side and the right side of the tank body can be generated in the reaction tank, high energy generated by the high-voltage electric arc is absorbed by grease substances in the wastewater, C-H bonds in grease molecules are excited by energy to be in an unstable state, C-H bonds are broken and recombined under the surface catalytic action of dichlorotetracarbonyl rhodium, finally macromolecule polymerization particles are generated and, and is discharged out of the reaction tank through a water outlet valve at the right side of the reaction tank and enters a tertiary sedimentation tank 8.
A microbubble air-float oil adsorption device 3 with an effective volume of 275m3The ultra-fine bubble generator 32 can generate ultra-fine bubbles 33 with the diameter less than 50 μm, the normal working voltage is 20V, and the working life is generally 5000 h. Volume of oil catalytic reforming desorption reactor 4Is 330m3The device can contain 5 pieces of vertically placed pi-allyl nickel compound modified diatomite adsorption films 42 to be subjected to high-temperature treatment, an electric heating air blower 44 can generate hot air at the temperature of 200-250 ℃, and the working voltage is 380V. The area of the pi-allyl nickel compound-modified diatomite adsorption film 42 is 10.2m2The content of the pi-allylnickel compound was 16.6g/m2The purity of the pi-allylnickel compound was 95.2%.
The restaurant wastewater treated by the system has the oil removal efficiency of 99.8 percent.