CN1302829C - Instrument for vortex cavitation and emulsion breaking - Google Patents

Instrument for vortex cavitation and emulsion breaking Download PDF

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Publication number
CN1302829C
CN1302829C CNB2004100662130A CN200410066213A CN1302829C CN 1302829 C CN1302829 C CN 1302829C CN B2004100662130 A CNB2004100662130 A CN B2004100662130A CN 200410066213 A CN200410066213 A CN 200410066213A CN 1302829 C CN1302829 C CN 1302829C
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cavitation device
oil
paraboloidal
cylinder
cone
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CNB2004100662130A
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CN1605375A (en
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贾金平
徐金球
侯士兵
王亚林
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Shanghai Jiaotong University
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Shanghai Jiaotong University
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Abstract

The present invention relates to a vortex cavitation device and vortex cavitation and emulsion breaking equipment thereof, which is used for the technical field of chemical engineering separation. The equipment comprises a storage tank, a pump, a pressure meter, a vortex cavitation device, a buffering tank and an oil and water separator, wherein the liquid outlet end of the storage tank is connected with the liquid inlet end of the pump through a pipeline by a valve, the liquid outlet end of the pump is connected with the liquid inlet end of the vortex cavitation device through a pipeline by the pressure meter, a nozzle of the vortex cavitation device is positioned above the liquid inlet end of the buffering tank, and the liquid outlet end of the buffering tank is connected with the liquid inlet end of the oil and water separator through a pipeline by a valve. The vortex cavitation device has three structural forms. After the vortex cavitation device and the matching device thereof are used for carrying out emulsion breaking treatment for emulsifying oil containing water or emulsifying wastewater containing oil, the dehydration rate or the oil removal rate can reach more than 92%, and the vortex cavitation device can carry out dewatering or oil removal treatment for oil and water emulsion under the condition of not adding chemical emulsion breaking agents or adding a little chemical emulsion breaking agents. The vortex cavitation device has simple equipment structure, large treating capacity for oil and water emulsion, little equipment investment and low cost.

Description

The equipment of convolution cavitation breakdown of emulsion
Technical field
The present invention relates to the equipment of a cover water-oil separating, specifically is a kind of equipment of convolution cavitation breakdown of emulsion, is used for technical field of chemical separation.
Background technology
The crude oil of extraction great majority mix output with natural gas and salt solution from oil well, and " crude oil " that obtains after gs-oil separator is isolated natural gas and free water generally remains Water-In-Oil (W/O) the type emulsion that contains a certain amount of salt and water.The existence of salt and water can increase the load of pump, pipeline and storage tank in the crude oil, and can cause the corrosion and the fouling of equipment and pipeline and make catalyst poisoning, therefore crude oil will be handled through desalting and dewatering earlier in conveying and first being processed, make wherein salt content and water content reach certain requirement.The oil recovery of petroleum industry, oil refining, store oil transportation and petro chemical industry, mechanical industry and food processing industry all can produce oily waste water, these oily waste waters have a large portion to exist with the form of oil emulsion, and to have suitable stability more difficult because of it.
Find by literature search, Chinese patent publication number: CN1424128A, patent name: a kind of high-frequency and high-voltage oil-water separation method and equipment, this equipment are to be made of tank body and the oil-feed distributing pipe, battery lead plate, the hanging beam that are located at high-voltage leading-in rod, flowline, outlet pipe, oil inlet pipe, the fluid level controller of tank body outside and are located at tank interior.After utilizing this equipment that ordinary crude oils, viscous crude are carried out water-oil separating and handle, the content that can make salt wherein is less than 3mg/L.But this equipment exists the manufacturing cost of equipment and operating cost is all higher and shortcoming such as complicated operation.
Summary of the invention
The objective of the invention is to, at above-mentioned the deficiencies in the prior art, a kind of equipment of convolution cavitation breakdown of emulsion is proposed, promptly a cover realizes containing the equipment of water-emulsified oil or emulsified oily watewater breakdown of emulsion, makes it can and not add or add less under the condition of chemical demulsifier in lower temperature and carry out low cost and the processing of high efficiency breakdown of emulsion to containing water-emulsified oil or emulsified oily watewater.
The present invention is achieved by the following technical solutions, the present invention includes: storage tank, pump (oil pump or water pump), pressure gauge, convolution cavitation device, dashpot and oily-water seperating equipment.The outlet end of storage tank is connected with the liquid feeding end of pump through valve by pipeline, the outlet end of pump is connected with the liquid feeding end of convolution cavitation device through pressure gauge by pipeline, the nozzle of convolution cavitation device is positioned at the top of dashpot liquid feeding end, and the outlet end of dashpot is connected with the liquid feeding end of oily-water seperating equipment through valve by pipeline.
The present invention handles the breakdown of emulsion that the convolution cavitation effect that should do one's utmost to avoid in the fluid machinery is applied to contain water-emulsified oil or emulsified oily watewater, has designed the convolution cavitation device of three kinds of different structures for this reason.
The convolution cavitation device of first kind of structure is made up of feed tube, three coaxial inner cylinders, middle cylinder, outer cylinder and nozzles, wherein outer cylinder and middle cylinder have their tops separately and common bottom, and inner cylinder is a hollow cylinder, inlet is alone respectively arranged in the top center position of middle cylinder and outer cylinder, middle cylinder and outer cylinder have common bottom, their bottom is connected with the entrance point of nozzle, and inner cylinder links to each other with middle cylinder with four radially equally distributed crossbeams.A plurality of tangential slits are arranged on the wall of the middle cylinder first half.
The convolution cavitation device of second kind of structure is made up of feed tube, paraboloidal cone, slit disk, deflector and nozzle.Feed tube and nozzle are separately fixed at the top and the bottom of paraboloidal cone, the slit disk is fixed on the paraboloidal cone on the position of its 1/10~3/4 times of cone height in top, a plurality of radial slit that distribute symmetrically along circumference are arranged on the slit disk, and deflector is fixed on the slit disk in the slit place.
The convolution cavitation device of the third structure is made up of feed tube, infundibulate inner cone, paraboloidal Outer Taper and nozzle.Feed tube and nozzle are separately fixed at the top and the bottom of paraboloidal Outer Taper, the conical arrival end of infundibulate inner cone is fixed on the paraboloidal Outer Taper on the position of its 1/10~1/2 times of cone height in top, and the pipe-type outlet end of infundibulate inner cone is positioned on the position of paraboloidal Outer Taper bottom top 0.2~2cm.
The present invention utilizes convolution cavitation device to carry out breakdown of emulsion to containing water-emulsified oil or emulsified oily watewater, (0.1~1MPa) and flow velocity during by convolution cavitation device, emulsion has formed high-speed eddy in the inside of cavitation device with certain pressure through the pump pressurization when the emulsion that contains water-emulsified oil or emulsified oily watewater.The control operation condition makes the eddy current pressure inside be lower than the saturated vapor pressure of emulsion continuous phase itself (as oil phase or water) or low boiling component wherein (as certain low boiling component in the crude oil), the continuous phase (as oil phase or water) of emulsion vaporization rapidly in the eddy current, being dissolved in little gas nuclear (as nitrogen and oxygen etc.) in the emulsion continuous phase simultaneously also can overflow and form bubble or cavity, the steam of continuous phase condenses and forms the minimum cavitation bubble of internal pressure of One's name is legion, when emulsion entered atmospheric area by the high-speed eddy state, these cavitation bubbles are collapse rapidly under the effect of the ambient pressure that increases suddenly.(be about 10 because the time compole that this process takes place is short -6~10 -8S), be similar to adiabatic process, therefore produced instantaneous high temperature and high pressure in the continuous phase inside of emulsion, follow a large amount of micro-waves simultaneously and form high-speed micro-jet, these factors make the fine droplet coalescence of emulsion decentralized photo grow up and separate out from continuous phase, and then reach the purpose of breakdown of emulsion.When emulsion formed high-speed eddy in the inside of cavitation device, the small emulsion droplet that reduces to make the emulsion decentralized photo (as water droplet or oil droplet) of pressure expanded, and has also promoted breakdown of emulsion.Contain water-emulsified oil or emulsified oily watewater and enter again in the oily-water seperating equipment, utilize that the profit two-phase goes out the difference of open height and realizes that oil phase and the automatic of water separate in this device through behind the convolution cavitation device breakdown of emulsion.This equipment both had been applicable to product oils such as handling moisture emulsified crude oil, aviation fuels, general oil product (as gasoline, kerosene, diesel oil, hydraulic oil, lubricating oil, transformer oil, edible wet goods) and special oil product, also be suitable for handling all kinds of emulsified oily watewaters, comprise petroleum industry, petro chemical industry, mechanical industry and the emulsified oily watewater that food processing industry produced.
Adopt equipment of the present invention all kinds ofly to contain water-emulsified oil or emulsified oily watewater dewaters or oil removal treatment to above-mentioned, not only has the good advantage of demulsification, simultaneously, because the required device structure of this complete equipment is simple,, equipment big to the treating capacity of water-oil emulsion cheap for manufacturing cost, equipment can not add in running or add chemical demulsifier less, thereby has the little and low advantage of operating cost of equipment investment.
Description of drawings
Fig. 1 is an outfit of equipment structural representation of the present invention
Fig. 2 is a kind of convolution cavitation device structural representation ()
Fig. 3 is a kind of convolution cavitation device structural representation (two)
Fig. 4 is an A-A cutaway view shown in Figure 3
A kind of convolution cavitation device structural representation of Fig. 5 (three)
The specific embodiment
As shown in Figure 1, the equipment of convolution cavitation breakdown of emulsion of the present invention comprises: storage tank 1, pump (oil pump or water pump) 2, pressure gauge 3, convolution cavitation device 4, dashpot 5 and oily-water seperating equipment 6.The outlet end of storage tank 1 links to each other with the liquid feeding end of pump 2 through valve by pipeline, the outlet end of pump 2 links to each other with the liquid feeding end of convolution cavitation device 4 through pressure gauge 3 by pipeline, the nozzle of convolution cavitation device 4 is positioned at the top of dashpot 5 liquid feeding ends, and the outlet end of dashpot 5 links to each other with the liquid feeding end of oily-water seperating equipment 6 through valve by pipeline.
As shown in Figure 2, convolution cavitation device 4 is made up of feed tube 7, three coaxial inner cylinders 8, middle cylinder 9, outer cylinder 10 and outlet sections 11, wherein outer cylinder 10 and middle cylinder 9 have their tops separately and common bottom, and inner cylinder 8 is a hollow cylinder, inlet is alone respectively arranged in the top center position of middle cylinder 9 and outer cylinder 10, middle cylinder 9 and outer cylinder 10 have common bottom, their bottom is connected with the entrance point of nozzle 11, and inner cylinder 8 links to each other with middle cylinder 9 with four radially equally distributed crossbeams.A plurality of tangential slits are arranged on the wall of middle cylinder 9 first halves.After containing water-emulsified oil or emulsified oily watewater pressurization enter the outer cylinder 10 of this convolution cavitation device with certain pressure and flow velocity through pump 2, wherein a part of fluid flows into inner cylinder 8 from the perforate of the top of middle cylinder 9, form axial jet, the zone during the remainder of fluid flows into by the tangential slit on middle cylinder 9 walls between cylinder 9 and the inner cylinder 8 forms eddy current.The control operation condition makes eddy current or jet pressure inside be lower than the saturated vapor pressure of emulsion continuous phase itself or low boiling component wherein, makes the inside of emulsion continuous phase produce the cavitation bubble of One's name is legion.When fluid is leaked by nozzle 11 and enters in the dashpot 5, these cavitation bubbles are collapse rapidly under the effect of the ambient pressure that increases suddenly, produce instantaneous HTHP, micro-wave and high-speed micro-jet, make fine droplet coalescence in the emulsion decentralized photo grow up and from continuous phase, separate out.
As shown in Figure 3, Figure 4, perhaps convolution cavitation device 4 comprises: feed tube 12, paraboloidal cone 13, slit disk 14, deflector 15 and nozzle 16.Feed tube 12 and nozzle 16 are separately fixed at the top and the bottom of paraboloidal cone 13, slit disk 14 is fixed on paraboloidal cone 13 on the position of its 1/10~3/4 times of cone height in top, a plurality of radial slit that distribute symmetrically along circumference are arranged on the slit disk 14, and deflector 15 is fixed on the slit disk 14 in the slit place.When contain water-emulsified oil or emulsified oily watewater flow into paraboloidal cones 13 from the feed tube 12 of convolution cavitation device 4 with certain pressure and flow velocity through pump 2 pressurization top through slit disk 14 from its slit along deflector 15 when flowing to the bottom of paraboloidal cone 13, its pressure inside reduces the generation eddy current suddenly.When fluid flow to the less nozzle 16 of section, the eddy current pressure inside further reduced.The control operation condition makes the pressure in the eddy current be lower than the saturated vapor pressure of emulsion continuous phase itself or low boiling component wherein, makes the cavitation bubble of the inside generation One's name is legion of emulsion continuous phase.When the nozzle 16 that flows through convolution cavitation device 4 when fluid enters in the dashpot 5, these cavitation bubbles are collapse rapidly under the effect of the ambient pressure that increases suddenly, produce instantaneous HTHP, micro-wave and high-speed micro-jet, make the fine droplet coalescence of decentralized photo in the emulsion grow up and from continuous phase, separate out.
As shown in Figure 5, perhaps convolution cavitation device 4 comprises: feed tube 17, paraboloidal Outer Taper 18, infundibulate inner cone 19 and nozzle 20.Feed tube 17 and nozzle 20 are separately fixed at the top and the bottom of paraboloidal Outer Taper 18, the conical arrival end of infundibulate inner cone 19 is fixed on paraboloidal Outer Taper 18 on the position of its 1/10~1/2 times of Outer Taper height in top, and the pipe-type outlet end of infundibulate inner cone 19 is positioned on the position of top, paraboloidal Outer Taper 18 bottoms 0.2~2cm.When the first half that flows into paraboloidal Outer Taper 18 with certain pressure and flow velocity from the feed tube 17 of convolution cavitation device through pump 2 pressurization when emulsion entered infundibulate inner cone 19 again and arrives the tiny pipe-type outlet end of its calibers, its pressure inside reduced the formation eddy current suddenly.The control operation condition makes the pressure in the eddy current be lower than the saturated vapor pressure of emulsion continuous phase itself or low boiling component wherein, makes the cavitation bubble of the inside generation One's name is legion of emulsion continuous phase.When the nozzle 20 that flows through convolution cavitation device 4 by the pipe-type outlet end of infundibulate inner cone 19 when fluid enters in the dashpot 5, these cavitation bubbles are collapse rapidly under the effect of the ambient pressure that increases suddenly, produce instantaneous HTHP, micro-wave and high-speed micro-jet, make the fine droplet coalescence of decentralized photo in the emulsion grow up and from continuous phase, separate out.
Below by specific embodiment technical scheme of the present invention is further described.
Embodiment 1~3:
The w/o type emulsified coarse-oil contained water 22.5% in certain oil field, asphaltenes 2.6%, proportion 0.93, viscosity in the time of 50 ℃ is 103mPas, volume is 100 liters, is under 55 ℃ the condition in temperature, is the convolution cavitation device of three kinds of structures of 0.7cm respectively by the jet expansion diameter with the pressure of 0.8MPa, the time of staying of oil-water mixture in gravitational separation device is 60 minutes, and the dehydration rate of emulsified crude oil is respectively 92.5%, 93.7% and 92.2%.
Embodiment 4~6:
Use proportion is diesel oil and three parts of emulsified oily watewater samples of surfactant preparation of 0.823, the content of oil is 1000mg/L in the waste water, particle size range is that the oil droplet of 0.5~10 μ m all accounts for 95% in the water, the volume of waste water is 100 liters, be under 25 ℃ the condition in the temperature of waste water, be the convolution cavitation device of three kinds of structures of 0.7cm respectively by the jet expansion diameter with the pressure of 0.8MPa, the time of staying of waste water in gravitational separation device is 30 minutes, and the oil removal rate of emulsified oily watewater is respectively 95.7%, 94.3% and 92.8%.

Claims (3)

1, a kind of equipment of convolution cavitation breakdown of emulsion, comprise: storage tank (1), pump (2), pressure gauge (3), dashpot (5) and oily-water seperating equipment (6), it is characterized in that also comprising: convolution cavitation device (4), the outlet end of storage tank (1) links to each other with the liquid feeding end of pump (2) through valve by pipeline, the outlet end of pump (2) links to each other with the liquid feeding end of convolution cavitation device (4) through pressure gauge (3) by pipeline, the nozzle of convolution cavitation device (4) is positioned at the top of dashpot (5) liquid feeding end, the outlet end of dashpot (5) links to each other with the liquid feeding end of oily-water seperating equipment (6) through valve by pipeline, and wherein convolution cavitation device (4) adopts one of following three kinds of forms:
A, convolution cavitation device (4) comprising: feed tube (7), three coaxial inner cylinders (8), middle cylinder (9), outer cylinder (10) and outlet section (11), outer cylinder (10) and middle cylinder (9) have their tops separately and common bottom, and inner cylinder (8) is a hollow cylinder, inlet is alone respectively arranged in the top center position of middle cylinder (9) and outer cylinder (10), the bottom of middle cylinder (9) and outer cylinder (10) is connected with the entrance point of nozzle (11), inner cylinder (8) links to each other with middle cylinder (9) with four radially equally distributed crossbeams, and a plurality of tangential slits are arranged on the wall of middle cylinder (9) first half;
B, convolution cavitation device (4) comprising: feed tube (12), paraboloidal cone (13), slit disk (14), deflector (15) and nozzle (16), feed tube (12) and nozzle (16) are separately fixed at the top and the bottom of paraboloidal cone (13), slit disk (14) is fixed on the paraboloidal cone (13), the slit disk has slit on (14), deflector (15) is fixed on the slit disk (14) in the slit place, and a plurality of radial slit that distribute symmetrically along circumference are arranged on the slit disk (14);
C, convolution cavitation device (4) comprising: feed tube (17), paraboloidal Outer Taper (18), infundibulate inner cone (19) and nozzle (20), feed tube (17) and nozzle (20) are separately fixed at the top and the bottom of paraboloidal Outer Taper (18), and the conical arrival end of infundibulate inner cone (19), pipe-type outlet end are fixed on the paraboloidal Outer Taper (18).
2, the equipment of convolution cavitation breakdown of emulsion according to claim 1 is characterized in that, slit disk (14) is fixed on paraboloidal cone (13) on the position of its 1/10~3/4 times of cone height in top.
3, the equipment of convolution cavitation breakdown of emulsion according to claim 1, it is characterized in that, the conical arrival end of infundibulate inner cone (19) is fixed on paraboloidal Outer Taper (18) on the position of its 1/10~1/2 times of Outer Taper height in top, and the pipe-type outlet end of infundibulate inner cone (19) is positioned on the position of paraboloidal Outer Taper (18) bottom top 0.2~2cm.
CNB2004100662130A 2004-09-09 2004-09-09 Instrument for vortex cavitation and emulsion breaking Expired - Fee Related CN1302829C (en)

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GB2457494B (en) * 2008-02-15 2012-04-25 E2V Tech Uk Ltd RF heating of a dielectric fluid
WO2023047169A1 (en) * 2021-09-27 2023-03-30 Avonlea Technology Holdings Corp. Water emulsions separation system and process

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5032273A (en) * 1984-09-10 1991-07-16 Senyard Sr Corley P Apparatus for separating sand and oil from a waste water stream
CN2137563Y (en) * 1992-01-16 1993-07-07 石油大学(华东) Rotary jet-flow generating device with guide impeller
CN1139419C (en) * 1997-06-27 2004-02-25 莫普罗产品有限公司 Apparatus and method for separating mixture of less dense liquid and more dense liquid
CN2626980Y (en) * 2003-06-13 2004-07-21 中国石化集团上海工程有限公司 Device for processing oily sewage

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5032273A (en) * 1984-09-10 1991-07-16 Senyard Sr Corley P Apparatus for separating sand and oil from a waste water stream
CN2137563Y (en) * 1992-01-16 1993-07-07 石油大学(华东) Rotary jet-flow generating device with guide impeller
CN1139419C (en) * 1997-06-27 2004-02-25 莫普罗产品有限公司 Apparatus and method for separating mixture of less dense liquid and more dense liquid
CN2626980Y (en) * 2003-06-13 2004-07-21 中国石化集团上海工程有限公司 Device for processing oily sewage

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