Cleaning system of membrane emulsification equipment

Abstract

The utility model discloses a cleaning system of membrane emulsification equipment, which comprises an emulsifier system, a heat source circulation system and a cleaning system, the cleaning system comprises an organic solvent tank body system, an organic solvent filtering circulating system, an organic solvent filter body system, an organic solvent oil supply circulating system, an organic solvent backflow circulating system, a heating system and a pollution discharge and steam exhaust system. Compared with the prior art, a cleaning program is cut in or cut out by monitoring the deviation of a transmembrane pressure difference value of the emulsifier to a set value, so that intelligent cleaning is realized; the non-ionic surfactant is adopted as a cleaning medium, the surface tension of a film is reduced, damage to the film and equipment is reduced, and equipment cleaning is completed.

Description

Technical Field

[0001] The utility model relates to the technical field of heavy oil membrane emulsification, in particular to a cleaning system for a membrane emulsification device. Background Technique

[0002] Globally, heavy oil resources are very rich, with reserves about 6-7 times that of conventional crude oil. With the rising price of crude oil, the crude oil becomes heavier and inferior, and the demand for light oil products increases. It has become more and more urgent to refine heavy oil into light oil products such as gasoline and diesel. As an important energy source in China, heavy oil membrane emulsification technology is one of the methods to improve the utilization rate of heavy oil.

[0003] During the heavy oil emulsification process, due to the fluctuation of production conditions, heavy oil backflow may occur, resulting in the blockage of the microchannels of the emulsifying medium, the decrease of the emulsification flux, and the further increase of the transmembrane pressure difference (the pressure difference between the raw material side and the permeate side), leading to the shutdown of the system due to overpressure and the reduction of equipment utilization rate. Therefore, equipment cleaning is required during the production operation process. The cleaning of the membrane surface can be divided into in-situ cleaning and non-in-situ cleaning according to whether the membrane module is disassembled and removed during cleaning; according to the cleaning method, it is divided into physical cleaning and chemical cleaning. Physical cleaning mainly uses methods such as water, gas flushing and purging, with a short duration, and can only remove larger particulate matter attached to the membrane surface; chemical cleaning generally uses acid-base cleaning methods, using high-strength alkaline solutions such as sodium hydroxide and sodium carbonate to soften, loosen and disperse sediments or using acidic solutions to remove surface oxides. Both are prone to produce chemical waste liquid, resulting in high damage to the membrane emulsification equipment, high operation risks for workers and the need for shutdown operation. During the heavy oil emulsification process, due to its large amount of impurities and complex components, it is easy to cause the blockage of membrane pores. The traditional cleaning methods cannot meet the normal production requirements. Summary of the Invention

[0004] The purpose of the utility model is to address the problems that during the heavy oil emulsification process, a large amount of impurities are easily generated, the impurity components are complex, and it is easy to cause the blockage of membrane pores. Existing physical cleaning methods for membranes can only remove larger particulate matter attached to the membrane surface; using chemical cleaning methods to clean membranes is prone to produce chemical waste liquid, resulting in high damage to the membrane emulsification equipment, high operation risks for workers and the need for shutdown operation, increasing the operating cost. For this deficiency, a cleaning system and method for a membrane emulsification device are proposed.

[0005] In order to achieve the above objectives, the utility model adopts the following technical solutions:

[0006] A cleaning method for a membrane emulsification device includes the following steps:

[0007] S1. Preset a threshold for the transmembrane pressure difference in the emulsifier and set the floating range of the transmembrane pressure difference;

[0008] S2. Obtain the transmembrane pressure difference in the current emulsifier;

[0009] S3. Determine whether the current transmembrane pressure difference is greater than or equal to the upper bound of the threshold floating range. If the current transmembrane pressure difference is greater than or equal to the upper bound, perform the cleaning procedure in step S4;

[0010] S4. Feed an organic solvent into the emulsifier for circulation. And after the first cleaning time, add a surfactant to the organic solvent, soak the emulsifier, and then continue to rinse for the second time;

[0011] S5. After the cleaning is completed, determine whether the transmembrane pressure difference after cleaning is within the floating range of the threshold. If the transmembrane pressure difference after cleaning is less than the upper bound of the floating range, the cleaning is completed. Otherwise, continue to perform the cleaning procedure in step S4 until the transmembrane pressure difference is less than the upper bound of the floating range.

[0012] The first time is 2h - 3h; the soaking time is 30min - 50min; the second time is 10min - 20min.

[0013] The surfactant is a non-ionic surfactant, and the mass ratio of the surfactant to the organic solvent is 0.1~1:1.

[0014] The non-ionic surfactant is a polymer of fatty alcohol or fatty acid and ethylene oxide or acrylic acid.

[0015] The non-ionic surfactant is Tween or Span series surfactant.

[0016] After the cleaning is completed, recover the organic solvent and perform filtration and purification treatment.

[0017] A cleaning system for a membrane emulsification device, comprising:

[0018] A membrane emulsification system for performing membrane emulsification treatment on heavy oil;

[0019] An organic solvent tank for storing the organic solvent;

[0020] An organic solvent filter connected to the organic solvent tank for filtering and removing impurities from the organic solvent;

[0021] An organic solvent feeding device for feeding the organic solvent in the organic solvent tank into the organic solvent filter;

[0022] An organic solvent circulation tank connected to the membrane emulsification system for storing the organic solvent during the cleaning process;

[0023] The organic solvent circulation tank is also connected to the organic solvent tank through a valve;

[0024] In the membrane emulsification system, a porous ceramic membrane is used as the emulsification medium, and the membrane emulsification system further includes a pressure measurement unit for detecting the transmembrane pressure difference across the porous ceramic membrane.

[0025] The organic solvent feeding device includes a plunger pump.

[0026] In the organic solvent filter, a metal filter element is used as the filtering unit, with a pore size of 0.1 - 5 μm.

[0027] It further includes: a steam heating system connected to the organic solvent tank and / or the organic solvent filter for heating the organic solvent tank and / or the organic solvent filter.

[0028] A sewage discharge device is provided at the bottom of the organic solvent tank and the organic solvent filter.

[0029] Diesel oil is contained in the organic solvent tank.

[0030] A surfactant feeding port is further provided on the organic solvent tank for adding surfactant into the organic solvent tank.

[0031] The organic solvent tank is a jacketed pressure vessel.

[0032] A cleaning system and method for a membrane emulsification device proposed by the present utility model have the following beneficial effects compared with the prior art:

[0033] 1. The present utility model cuts into or out of the cleaning program by monitoring the deviation of the transmembrane pressure difference value of the emulsifier from the set value;

[0034] 2. The present utility model uses a non - ionic surfactant as the cleaning medium to reduce the surface tension of the membrane, reduce damage to the membrane and the device, and complete the cleaning of the device. Description of the Drawings

[0035] Figure 1 is the structural schematic diagram of the present utility model;

[0036] The meanings of the reference numerals in the drawings: 01, organic solvent tank; 10, filtration circulation pipe; 11, plunger pump inlet valve; 12, drain valve; 13, plunger pump; 14, plunger pump outlet check valve; 15, stop valve; 16, pressure gauge; 17, filter inlet valve; 20, organic solvent filter; 30, oil supply circulation pipe; 31, filter outlet valve; 40, organic solvent return pipeline; 43, inlet electric valve; 50, heating pipeline; 51, solvent tank inlet stop valve; 52, filter steam inlet solenoid valve; 60, first sewage discharge valve; 61, regular sewage discharge valve; 62, first orifice plate; 63, second sewage discharge valve; 64, steam exhaust valve; 65, second orifice plate; 66, third sewage discharge valve; 70, skid - mounted reserved flange interface; 8, surfactant feeding port. Detailed implementation mode

[0037] The following is a specific introduction to the present utility model in combination with the accompanying drawings and specific embodiments.

[0038] Embodiment 1: In combination with Figure 1 , a cleaning system for a membrane emulsification device, comprising an emulsifier system, a heat source circulation system and a cleaning system. The emulsifier system includes an emulsifier (here, the emulsifier uses a porous ceramic membrane for membrane emulsification treatment, which can be referred to the prior art. Heavy oil flows through one side of the porous ceramic membrane, penetrates through the membrane pores, and contacts the continuous phase solvent phase on the permeation side to obtain emulsified heavy oil). The cleaning system includes an organic solvent tank 01 body system, an organic solvent filtration and circulation system, an organic solvent filter 20 body system, an organic solvent supply and circulation system, an organic solvent reflux and circulation system, a heating system, and a sewage and exhaust system.

[0039] Among them, the organic solvent tank 01 body system is used to store the organic solvent for cleaning the emulsifier and heat the organic solvent through a heating source; the organic solvent tank 01 body system includes an organic solvent tank 01; a feeding port, a liquid level gauge, a field pressure gauge, a thermometer and a safety valve are arranged on the organic solvent tank 01. The organic solvent tank 01 is set as a jacketed pressure vessel; the organic solvent tank 01 is selected as a jacketed pressure vessel with a volume of 1m 3 , and the shell material is S30408;

[0040] The organic solvent filter 20 body system is used to purify and filter impurities in the organic solvent; the organic solvent filter 20 body system includes an organic solvent filter 20. A liquid level gauge, a differential pressure gauge, a field pressure gauge, a thermometer and a safety valve are arranged on the organic solvent filter 20. The organic solvent filter 20 is selected with a shell material of S30408, a metal filter element material of 316L, and a filtration accuracy of 1 micron.

[0041] The organic solvent filtration and circulation system is used to transport the high-temperature organic solvent to the organic solvent filter 20; the organic solvent filtration and circulation system includes a filtration circulation pipe 10, one end of which is connected to the organic solvent tank 01 and the other end is connected to the organic solvent filter 20. The organic solvent filtration and circulation system further includes a plunger pump inlet valve 11, a drain valve 12, a plunger pump 13, a plunger pump outlet check valve 14, a stop valve 15, a pressure gauge 16 and a filter inlet valve 17. The plunger pump 13 is selected with a flow rate of 5m 3 / h and a head of 250m;

[0042] An organic solvent circulation system for delivering filtered organic solvent to an emulsifier system; the organic solvent circulation system includes an oil supply circulation pipe 30, one end of which is connected to an organic solvent filter 20 and the other end is connected to an emulsifier. A filter outlet valve 31 is provided at one end of the oil supply circulation pipe 30 close to the organic solvent filter 20. A pressure gauge is provided on the oil supply circulation pipe 30.

[0043] An organic solvent reflux circulation system for recycling the cleaned organic solvent to an organic solvent tank 01. The organic solvent reflux circulation system includes an organic solvent reflux pipeline 40, one end of which is connected to an emulsifier and the other end is connected to the organic solvent tank 01. An inlet electric valve 43 is provided at one end of the organic solvent reflux pipeline 40 close to the organic solvent tank 01. A pressure gauge 16 is provided on the organic solvent reflux pipeline 40.

[0044] A steam heating system for providing a heat source for heating the organic solvent. The steam heating system includes a heating pipeline 50. One end of the heating pipeline 50 is connected to a heat source and the other end is connected to the organic solvent tank 01. A solvent tank inlet stop valve 51 is provided at one end of the heating pipeline 50 close to the organic solvent tank 01. The heating pipeline 50 is also connected to the organic solvent filter 20 for preheating the organic solvent filter 20. A filter steam inlet solenoid valve 52 is provided at one end of the heating pipeline 50 close to the organic solvent filter 20.

[0045] The filter circulation pipe 10, the oil supply circulation pipe 30 and the organic solvent reflux pipeline 40 are made of pipes with a pipe material of 0Gr18Ni9. The heating pipeline 50 is made of a DN20 seamless steel pipe.

[0046] The sewage and exhaust system includes a first sewage valve 60, a regular sewage valve 61, a first orifice plate 62, a second sewage valve 63, an exhaust valve 64, a second orifice plate 65 and a third sewage valve 66.

[0047] The first sewage valve 60 is provided below the organic solvent tank 01 for controlling the temperature inside the organic solvent tank 01 by controlling the opening degree of the first sewage valve 60.

[0048] The regular sewage valve 61, the first orifice plate 62 and the second sewage valve 63 are all provided below the organic solvent filter 20. The regular sewage valve 61 is connected to the organic solvent filter 20. One end of the first orifice plate 62 is connected to the organic solvent filter 20 and the other end is connected to the second sewage valve 63.

[0049] The exhaust valve 64, the second orifice plate 65 and the third sewage valve 66 are all provided above the organic solvent filter 20. The exhaust valve 64 is connected to the organic solvent filter 20. One end of the second orifice plate 65 is connected to the organic solvent filter 20 and the other end is connected to the third sewage valve 66.

[0050] The cleaning system is set as a skid-mounted structure, and skid-mounted reserved flange interfaces 70 are provided at both the connection between the cleaning system and the heat source circulation system and the connection between the cleaning system and the emulsifier system.

[0051] Working principle: The cleaning equipment is connected to the organic solvent tank 01 and the low-pressure steam pipeline (or other heat sources) between the original heavy oil film emulsification equipment and the low-pressure steam pipeline (or other heat sources) through the skid-mounted reserved flange interface 70. The organic solvent filter 20 is connected to the feed pipeline of the original heavy oil film emulsification equipment, and the organic solvent tank 01 is connected to the outlet pipeline of the original emulsifier. The preparation work is completed.

[0052] 800 - 1000 L of organic solvent is injected into the organic solvent tank 01 through the feeding port. The organic solvent tank 01 is connected to the low-pressure steam (or other heat sources) from the production line. The inlet stop valve 51 of the solvent tank and the solenoid valve 52 at the steam inlet of the filter are opened, and low-pressure steam is introduced to heat the organic solvent. The organic solvent is heated to 80 - 180 °C. When the thermometer on the organic solvent tank 01 shows above 150 °C, the solenoid valve 52 at the steam inlet of the filter for the low-pressure steam (or other heat sources) is closed. The inlet valve 11 of the plunger pump, the check valve 14 at the outlet of the plunger pump, the stop valve 15, the inlet valve 17 of the filter, the outlet valve 31 of the filter, and the inlet electric valve 43 are opened. The plunger pump 13 is started, and the organic solvent starts to circulate. The organic solvent passes through the organic solvent filter 20 in sequence through the plunger pump 13 and enters the original heavy oil film emulsification equipment. Subsequently, the organic solvent circulates back to the organic solvent tank 01 for 2 - 3 hours of circulating cleaning; subsequently, span 80 (surfactant, and the addition amount of the surfactant is 0.1% - 1% of the mass of the cleaning medium) is injected through the feeding port 8; the plunger pump 13 stops pumping to keep the medium soaked in the heavy oil emulsification equipment for 30 - 50 minutes. The surfactant can effectively reduce the interfacial tension of the membrane channel, enabling the emulsification medium to pass through the membrane channel cleaned by the organic solvent with low resistance and effectively restoring the membrane flux; subsequently, circulating cleaning is carried out; when the transmembrane pressure difference of the heavy oil emulsification equipment is less than the preset value, the cleaning mode is switched out.

[0053] Example 2: A cleaning method for a membrane emulsification equipment, comprising the following steps:

[0054] S1. Corresponding to the transmembrane pressure difference in the emulsifier, a threshold value is obtained, and a floating range of the transmembrane pressure difference is set; the floating range is set as the threshold value ±30%.

[0055] S2. Obtain the transmembrane pressure difference in the current emulsifier.

[0056] S3. Judge whether the value of the current transmembrane pressure difference is greater than or equal to the first threshold value.

[0057] S4. If the current transmembrane pressure difference is greater than or equal to the first threshold, the system operates normally and the cleaning system valve is opened.

[0058] Specifically, it includes the following steps:

[0059] S5.1. Add organic solvent and conduct circulating flushing for 2h - 3h; the organic solvent is set as diesel oil after heating and filtration.

[0060] S5.2. Add surfactant, stop circulating flushing, and immerse the heavy oil emulsification equipment in the medium for 30min - 50min; the surfactant is Span 80 non-ionic surfactant, and the mass ratio of the surfactant to the cleaning medium is 0.1~1:1.

[0061] S5.3. Use the organic solvent to conduct circulating flushing again for 10min - 20min.

[0062] The above shows and describes the basic principles, main features and advantages of the present utility model. Those skilled in the art should understand that the above embodiments do not limit the present utility model in any form. Any technical solutions obtained by means of equivalent replacement or equivalent transformation fall within the protection scope of the present utility model.

Claims

1. A cleaning system for a membrane emulsification device, characterized in that, Comprising: A membrane emulsification system for membrane emulsification treatment of heavy oil; An organic solvent tank (01) for storing organic solvents; An organic solvent filter (20) connected to the organic solvent tank (01) for filtering impurities from the organic solvents; An organic solvent feeding device for feeding the organic solvents in the organic solvent tank (01) into the organic solvent filter (20); An organic solvent circulation tank (4) connected to the membrane emulsification system for storing organic solvents during the cleaning process; The organic solvent circulation tank (4) is also connected to the organic solvent tank (01) through a valve; In the membrane emulsification system, a porous ceramic membrane is used as the emulsification medium, and a pressure measurement unit is further included in the membrane emulsification system for detecting the transmembrane pressure difference across the porous ceramic membrane; 2. The cleaning system of the membrane emulsification device according to claim 1, characterized in that, The organic solvent feeding device includes a plunger pump (13); 3. The cleaning system of the membrane emulsification device according to claim 1, characterized in that In the organic solvent filter (20), a metal filter element is used as the filtering unit with a pore size of 0.1 - 5 μm; 4. The cleaning system of the membrane emulsification device according to claim 1, characterized in that, Also comprising: A steam heating system connected to the organic solvent tank (01) and / or the organic solvent filter (20) for heating the organic solvent tank (01) and / or the organic solvent filter (20); 5. The cleaning system of the membrane emulsification device according to claim 1, characterized in that, A sewage discharge device is provided at the bottom of the organic solvent tank (01) and the organic solvent filter (20); 6. The cleaning system of the membrane emulsification device according to claim 1, characterized in that, Diesel oil is contained in the organic solvent tank (01); 7. The cleaning system of the membrane emulsification device according to claim 1, characterized in that, A surfactant feeding port (8) is further provided on the organic solvent tank (01) for adding surfactants into the organic solvent tank (01); 8. The cleaning system of the membrane emulsification device according to claim 1, characterized in that, The organic solvent tank is a jacketed pressure vessel.

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