WO2019024913A1

WO2019024913A1 - Radial particle-washing device

Info

Publication number: WO2019024913A1
Application number: PCT/CN2018/098501
Authority: WO
Inventors: 杨强; 耿坤宇; 孙荣江
Original assignee: 华东理工大学
Priority date: 2017-08-04
Filing date: 2018-08-03
Publication date: 2019-02-07
Also published as: CN107457257A

Abstract

Disclosed is a radial pipe-type particle-washing device, the washing device being divided into three different forms according to washing requirements and different properties of fed materials. The device comprises a straight pipe (4) and/or a Venturi pipe (6) used as a pipeline of the washing device. A mandrel (3) with an end provided with a flow guide cone, forward-rotating fins (2-1, 2-2), and backward-rotating fins (5-1, 5-2) are arranged in a pipe. The forward-rotating fins (2-1, 2-2) and the backward-rotating fins (5-1, 5-2) are sequentially arranged on the mandrel (3) with an end provided with a flow guide cone. The forward-rotating fins (2-1, 2-2) and the mandrel (3) with an end provided with a flow guide cone form a rotation-forming unit, and the backward-rotating fins (5-1, 5-2) and the mandrel (3) with an end provided with a flow guide cone form a reinforced mixing unit.

Description

Radial particle washing device

Technical field

The present invention relates to a particle washing apparatus, and more particularly to an apparatus for performing radial particle washing using swirling, cavitation and enhanced mixing coupling.

Background technique

In the process of petroleum production, storage, transportation, refining, processing and use, due to accidents, abnormal operations and maintenance, there will be spills and emissions of petroleum hydrocarbons, for example, blowout accidents during oilfield development, oil well waxing And oilfield ground equipment maintenance, oil refining and petrochemical production equipment overhaul. At present, China's oil companies produce about 700,000 tons of crude oil per year, of which about 70,000 tons enter the soil environment. The oil content of the soil surface layer (0-20cm) in the heavily polluted areas of Daqing and Liaohe oilfields in China is 30%-50%.

Due to the relatively backward process and poor airtightness of the major oilfields in the past 10 years, combined with the relatively backward environmental protection measures and impact assessment systems, and the lack of pollution control and remediation technologies, the degree of soil petroleum pollution in China is much higher than that of developed countries. The pollution is accumulating year by year, and the soil and groundwater ecological environment in some areas deteriorate to the irreparable edge. Jia Jianli et al. (2009) investigated the status of petroleum hydrocarbon pollution in different oil fields in China. Through the geographical environment of the northeastern China (Daqing Oilfield), North China (Huabei Oilfield), Northwest (Changqing Oilfield, Yumen Oilfield), South China (Jianghan Oilfield) and East China (Shengli Oilfield) with different geographical and climatic conditions Sampling analysis of 10-25cm soil in an oil field shows that the domestic oilfield soil has been polluted by different degrees of petroleum hydrocarbons. The petroleum hydrocarbon content in the soil can reach up to 23%, which is more than 6000-10000 times of the environmental background value of the area.

At present, soil remediation methods at home and abroad mainly include physical repair methods, chemical repair methods and bioremediation methods, but there are disadvantages such as high cost, incompleteness, long cycle, and large environmental conditions. The mechanical cleaning method is a commonly used method for removing petroleum substances in soil particles, and has many advantages such as low consumption, high efficiency, and low secondary pollution.

At present, the common mechanical cleaning methods in China are mainly impact jet reactors, stirred vessels and ultrasonic washing methods, but all three methods have certain drawbacks. For example, the patent authorization publication number is CN205032119U, and the name is a stirred tank. Although the device has a simple structure, the required space is large, and there is a large noise, and the temperature difference between the center of the tank and the material near the tank wall is easy to occur, which affects the washing effect. Another example is the patent CN102716869A, which is called a floating ultrasonic cleaning device. The energy consumption of the device is relatively high, and the large amount of particles cannot be washed at the same time, and once the silencing filler material is damaged, the noise pollution is serious. Therefore, it is necessary to develop an efficient and low-cost washing device suitable for soil particles contaminated by petroleum substances in China.

Summary of the invention

In view of the above problems, the present invention provides a radial particle washing apparatus. The device has the advantages of high efficiency, low energy consumption of no moving parts, compact structure, space saving and the like.

The specific technical solutions are as follows:

A radial tubular particle washing device is divided into three different forms depending on the washing requirements and the nature of the imported materials. The apparatus includes a straight tube and/or a venturi tube, the two tubes serving as conduits, respectively. The tube is provided with a mandrel with a guide cone at the end, a positive-rotating fin and a counter-rotating fin. The positive rotation and the reverse rotation fin are arranged on the mandrel with the guide cone before and after. The positively-rotating fin and the mandrel with the guiding cone constitute a spinning unit, and the counter-rotating fin and the mandrel with the guiding cone constitute an intensive mixing unit.

Further, the straight pipe has a diameter D and a length of 0.3-0.6D.

Further, the mandrel with a guide cone has a diameter of 0.3-0.6D, a length of D, and a cone angle of the guide cone ranges from 15 to 75 degrees.

Further, the venturi has a diameter D, a length of 0.3-0.6D, a contraction angle range of 23-35°, and a diffusion angle of 3-6°.

Further, the arrangement order of the positively-rotating fins and the counter-rotating fins may be four kinds, that is, positive, negative, positive, positive, negative, positive, negative, and reverse.

Further, the front end of the mandrel with the guiding cone at the inlet is 0.3-0.6D from the inlet of the device, and the distance from the end of the mandrel with the guiding cone at the outlet is 2D, and the outlet is provided with a guiding cone. The distance from the end of the mandrel to the exit is 0.3-0.6D.

Further, the positive-rotating fin has a helix angle of 5-50°, and the counter-rotating fin has a helix angle of 5-50°.

Further, the radial particle washing device inlet flow rate ranges from 8.46D ² -28.26D ² m ³ /h.

Further, the particle washing device is fed in a radial feed mode.

Further, the mandrel arrangement with the guide cone is coaxial.

Further, the radial particle washing device may be arranged in three ways, that is, a full straight tube arrangement; the full-texturial tube is arranged; the straight tube and the venturi tube are alternately arranged.

The invention has the beneficial effects that the liquid is quickly entered into the fin by the flow guiding cone, and then the venturi tube is used to cavitation and acceleration of the fluid, the spin-forming effect of the positive-rotating fin and the intensive mixing of the counter-rotating fin The organic combination of swirling and cavitation is achieved to achieve a better washing effect. It has high efficiency, low energy consumption of moving parts, compact structure and space saving.

DRAWINGS

1 is a schematic structural view of a device of Embodiment 1;

Figure 2 is a schematic view of the particle washing application of the present invention;

Figure 3 is a schematic structural view of a spinning unit;

Figure 4 is a schematic structural view of an intensive mixing unit;

Figure 5 is a schematic view of a straight tube structure;

Figure 6 is a schematic view of a venturi.

Symbol Description:

1 is the material inlet; 2-1 is the first-stage pipeline positive-rotating fin; 2-2 is the secondary pipeline positive-rotating fin; 3 is the mandrel with the guide cone at the end; 4 is the straight tube; -1 is a primary pipeline counter-rotating fin; 5-2 is a secondary pipeline counter-rotating fin; 6 is a venturi tube; 7 is a material outlet.

Detailed ways

Hereinafter, the present invention will be specifically described by way of examples. It is to be noted that the following examples are merely illustrative of the present invention and are not to be construed as limiting the scope of the present invention, and that those skilled in the art will make some non-essential improvements and adjustments in accordance with the teachings of the present invention. Still falling within the scope of protection of the present invention.

Example 1

The inventors of the present application have found through extensive and intensive research that, for particle washing, the conventional mechanical washing methods are mainly impact jet reactors, stirred vessels and ultrasonic washing methods. However, there are many drawbacks in the three methods, such as agitating the container, which requires a large space, a large noise, and a temperature difference between the center of the tank and the material near the tank wall, which affects the washing effect. Another example is the ultrasonic washing device, which has relatively high energy consumption and cannot satisfy a large number of particles washing at the same time, and once the sound-absorbing filling material is damaged, the noise pollution is serious. The combination of swirling and cavitation organic combination can achieve good washing effect, compact structure, small space requirement, low energy consumption and high washing efficiency, so it is most suitable. Based on the above findings, the present invention has been completed.

As shown in FIG. 1 , it is a schematic structural view of Embodiment 1 of the present invention. The radial washing device mainly comprises: 2-1 first-stage pipeline positive-rotating fin; 2-2 secondary pipeline positive-rotating fin; 3 end Main shaft with guide cone; 4 straight tube; 5-1 primary line reverse rotor fin; 5-2 secondary line reverse rotor fin; 6 venturi tube. A petrochemical plant uses a material inlet flow of 30 m ³ /h and an inlet pipe diameter of 0.1 m (D). According to the requirements of the washing effect and the nature of the material, the straight tube and the venturi tube are alternately arranged, as shown in Fig. 5 is a schematic diagram of a straight tube structure, and Fig. 6 is a schematic diagram of a venturi tube. The number of pipeline stages is two. The material passes through the inlet 1, and the particles to be washed flow into the primary washing line with the washing liquid. Through the diversion of the flow guiding cone, the solid-liquid mixture quickly enters the positive-rotating fin 2-1, and the swirling action of the positive-rotating fin 2-1, as shown in Fig. 3 is a schematic diagram of the structure of the spinning unit, and its flow form is horizontal The flow becomes a rotating flow. Under the action of swirling, the washing liquid is in full contact with the particles to be washed and collides. The petroleum contaminants in the solid particles and the washing liquid initially form an emulsified state. Then, the solid-liquid mixture enters the counter-rotating fin 5-1 under the diversion of the flow guiding cone after passing through the tube length of 2D. The anti-rotation fin 5-1 achieves the mixing effect of the enhanced washing liquid and the oil-containing solid particles by diffusion, convection and shearing. And increase the degree of liquid turbulence, and further improve the mixing effect. The solid-liquid mixture then exits the primary wash line after passing through a 0.5D tube. After a first-stage washing line, the elution rate reaches 95% or more for oil-containing solid particles having a diameter of >2 mm. The solid-liquid mixture treated by the first-stage washing pipeline enters the secondary washing pipeline, and the primary washing pipeline and the secondary washing pipeline are connected in a flange form. After passing through the tube length of 0.5D, the solid-liquid mixture quickly enters the positive-rotating fin 2-2 under the diversion of the flow-conducting cone, and the solid-state liquid is rotated by the rotation of the positive-rotating fin 2-2. The degree of flow is intensified, and the washing liquid is in contact with the particles to be washed, the collision is more severe, and the washing effect is remarkably improved. The solid-liquid mixture then enters the constricted section of the venturi 6 after passing through a length of 0.5D. Through the cavitation of the venturi 6, the cavitation rapidly generates, expands and collapses, forming shock waves and high-speed microjets in the liquid, reducing the adhesion of petroleum substances to the solid particles. And the unique constricted structure of the venturi 6 reduces the pressure, and according to the Bernoulli equation, the flow rate is increased to achieve the effect of accelerating the flow. The increase in speed also increases the Reynolds number, further increases the degree of turbulence, and enhances the solid particle washing effect. After the washing liquid and solid particles in the constricted section of the venturi tube 6, after a length of 0.5D, the diversion fins are introduced under the diversion of the flow guiding cone to strengthen the mixing. Figure 4 is a schematic diagram of the structure of the reinforced mixing unit. Then, the washing device is left in the tube length of 0.5D to complete the washing. After washing by the secondary washing line, the oil removal rate is over 98% for oily solid particles having a diameter > 2 mm. For oil-containing solid particles having a diameter of 0.05 to 2 mm, the elution rate is 80% or more.

As shown in Fig. 2, it is a schematic diagram of the particle washing application of the present invention, wherein 1 is a liquid storage tank, 2 is a vibrating screen, 3 is a radial particle washing device, 4 is a heater, and 5 is a flash tank. The washing liquid enters the vibrating screen 2 from the liquid storage tank 1 through a pipe, and the liquid distributor passing through the top of the vibrating screen is uniformly distributed on the solid particles to be washed. Through the screening of the vibrating screen, the particles with larger particle diameter are directly backfilled, and the particles with smaller particle size enter the radial particle washing device together with the washing liquid. The solid-liquid ratio is adjusted to prevent blockage of the pipe by adjusting the valve opening of the line between the washing liquid and the radial particle washing device. After the solid particles and the washing liquid are sufficiently washed by the radial particle washing device, the heater 4 is introduced to dry the solid particles, and the dried solid particles are backfilled. The mixed steam of the washing liquid heated by the heater 4 and the petroleum substance enters the flash tank 5, and the flashing action of the flash tank 5 separates the washing liquid from the petroleum substance, the petroleum substance is recovered, and the washing liquid enters. The liquid storage tank 1 achieves circulation. Among them, the conventional particle washing device 3 has a compact structure, a small space requirement, a low energy consumption, a high washing efficiency, and good applicability, and the like.

Claims

A radial particle washing device, characterized in that the device comprises a straight tube and/or a venturi tube, a mandrel with a guiding cone at the inner end of the tube, a positively rotating fin and a counter-rotating fin; The positively-rotating fin and the mandrel with the guiding cone constitute a spinning unit, and the counter-rotating fin and the mandrel with the guiding cone constitute an intensifying mixing unit.
The apparatus of claim 1 wherein said straight tube has a diameter D and a length of 3-6D.
The apparatus according to claim 1 wherein said venturi has a diameter D, a length of 3-6 D, a contraction angle in the range of 20-40°, and a diffusion angle of 3-6°.
The device according to claim 1, wherein said mandrel with a guiding cone is arranged in a coaxial arrangement; said mandrel with a guiding cone having a diameter of 0.3-0.6D The length is 1.1-1.3D, and the cone angle of the guide cone ranges from 15-75°.
The apparatus according to claim 1, wherein said positive-rotating fin has a helix angle of 5 to 50° and a counter-rotating fin has a helix angle of 5 to 50°.
The apparatus according to claim 1, wherein said particle washing device is arranged in the following three manners: a full straight tube arrangement, a full-texture tube arrangement or a straight tube and a venturi tube. Alternately arranged.
The apparatus according to claim 5, wherein the arrangement order of the positively-rotating fins and the counter-rotating fins is four, that is, positive, negative, positive, positive, negative, positive, negative, and reverse.
The device according to claim 1, wherein the front end of the mandrel with the guide cone at the inlet is 0.3-0.6 D from the inlet of the device, and the distance from the mandrel with the guide cone at the end from the exit. For the 1.8-2.5D, the end of the mandrel with the guide cone at the exit is 0.3-0.6D from the exit.
The apparatus according to claim 1, wherein said radial particle washing device inlet flow rate ranges from 2826D 2 to 8478D 2 m 3 /h
The apparatus of claim 1 wherein said particulate scrubber is fed in a radial feed.