WO2022056777A1 - 甲醇制烯烃水洗水工艺连续运行周期延长的方法及装置 - Google Patents

甲醇制烯烃水洗水工艺连续运行周期延长的方法及装置 Download PDF

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WO2022056777A1
WO2022056777A1 PCT/CN2020/115855 CN2020115855W WO2022056777A1 WO 2022056777 A1 WO2022056777 A1 WO 2022056777A1 CN 2020115855 W CN2020115855 W CN 2020115855W WO 2022056777 A1 WO2022056777 A1 WO 2022056777A1
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Prior art keywords
water
washing water
separator
methanol
oil
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English (en)
French (fr)
Inventor
吕文杰
汪华林
陈建琦
刘昱
施磊
乔立功
张洁
昌国平
刘冰
崔馨
桑伟迟
王劲松
马红鹏
袁威
纪玉杰
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East China University of Science and Technology
Shanghai Huachang Environmental Protection Co Ltd
Sinopec Guangzhou Engineering Co Ltd
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East China University of Science and Technology
Shanghai Huachang Environmental Protection Co Ltd
Sinopec Guangzhou Engineering Co Ltd
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Application filed by East China University of Science and Technology, Shanghai Huachang Environmental Protection Co Ltd, Sinopec Guangzhou Engineering Co Ltd filed Critical East China University of Science and Technology
Priority to EP20953635.8A priority Critical patent/EP4215497A4/en
Priority to PCT/CN2020/115855 priority patent/WO2022056777A1/zh
Priority to US18/245,625 priority patent/US20230406728A1/en
Publication of WO2022056777A1 publication Critical patent/WO2022056777A1/zh
Anticipated expiration legal-status Critical
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    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F9/00—Multistage treatment of water, waste water or sewage
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/40—Devices for separating or removing fatty or oily substances or similar floating material
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D17/00—Separation of liquids, not provided for elsewhere, e.g. by thermal diffusion
    • B01D17/02—Separation of non-miscible liquids
    • B01D17/0205—Separation of non-miscible liquids by gas bubbles or moving solids
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/02—Treatment of water, waste water, or sewage by heating
    • C02F1/04—Treatment of water, waste water, or sewage by heating by distillation or evaporation
    • C02F1/16—Treatment of water, waste water, or sewage by heating by distillation or evaporation using waste heat from other processes
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/001—Processes for the treatment of water whereby the filtration technique is of importance
    • C02F1/004—Processes for the treatment of water whereby the filtration technique is of importance using large scale industrial sized filters
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/20—Treatment of water, waste water, or sewage by degassing, i.e. liberation of dissolved gases
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/24—Treatment of water, waste water, or sewage by flotation
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/38—Treatment of water, waste water, or sewage by centrifugal separation
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2101/00—Nature of the contaminant
    • C02F2101/30—Organic compounds
    • C02F2101/32—Hydrocarbons, e.g. oil
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2209/00—Controlling or monitoring parameters in water treatment
    • C02F2209/02—Temperature
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2209/00—Controlling or monitoring parameters in water treatment
    • C02F2209/03—Pressure
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2209/00—Controlling or monitoring parameters in water treatment
    • C02F2209/10—Solids, e.g. total solids [TS], total suspended solids [TSS] or volatile solids [VS]
    • C02F2209/105—Particle number, particle size or particle characterisation
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2209/00—Controlling or monitoring parameters in water treatment
    • C02F2209/40—Liquid flow rate
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2301/00—General aspects of water treatment
    • C02F2301/02—Fluid flow conditions
    • C02F2301/026—Spiral, helicoidal, radial
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2301/00—General aspects of water treatment
    • C02F2301/04—Flow arrangements
    • C02F2301/046—Recirculation with an external loop
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2301/00—General aspects of water treatment
    • C02F2301/06—Pressure conditions
    • C02F2301/066—Overpressure, high pressure
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2303/00—Specific treatment goals
    • C02F2303/16—Regeneration of sorbents, filters
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2303/00—Specific treatment goals
    • C02F2303/24—Separation of coarse particles, e.g. by using sieves or screens
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P30/00—Technologies relating to oil refining and petrochemical industry
    • Y02P30/40—Ethylene production

Definitions

  • the present disclosure belongs to the field of comprehensive treatment of environmental pollution, and relates to a method for removing grease and catalyst particles in the washing water of a methanol-to-olefins process by using a microcyclone separator and an ebullated bed separator for long-term operation, and is especially suitable for the continuous and stable operation of separation equipment.
  • the post-cleaning and maintenance of related equipment is reduced.
  • the present disclosure provides a combined separation method and device for long-cycle operation of methanol-to-olefin washing water, and the waste liquid, waste gas and washing water generated in the regeneration of the separation device by combining cyclone separation and particle bed separation and backwashing technology.
  • Comprehensive treatment method for waste heat recovery of clear water is provided.
  • MTO Methanol to Olefins
  • MTO Methanol to Olefins
  • the reaction is generally realized by a fluidized bed reactor, and most of the catalysts currently used are SAPO-34 molecular sieves of 200 nm to 20 ⁇ m.
  • the high-temperature product gas in the reactor is sent to the quenching tower after recovering the catalyst powder through the three-stage cyclone.
  • the gas is cooled to about 109 °C by the quenching tower and then sent to the washing tower for washing, and then sent to the olefin separation unit after washing.
  • some fine catalyst powders with a particle size of less than 10 ⁇ m are sent to the quenching tower with the product gas.
  • unreacted methanol, dimethyl ether and other organic oxygen-containing compounds and a small amount of reacted intermediate product oil and wax substances (more than 90% are aromatics) will enter the quenching tower and the water washing tower together with the reaction gas. Due to the high operating temperature of the quench tower and the short contact time between the product gas and the quench water, the quench tower can wash most of the catalyst fines, while most of the organic oxygen-containing compounds and oil wax enter the washing water.
  • the waste water condensed from the washing tower usually contains SAPO-34 molecular sieve catalyst powder of 0.5 ⁇ m to 20 ⁇ m and a small amount of organic oxygen-containing compounds such as methanol and dimethyl ether, and aromatic hydrocarbons.
  • Substances oil content of 200 to 700 mg/L
  • high temperature wastewater 85 to 95 °C.
  • the cyclone degreaser does not completely remove the oil and wax in the water; and because the water contains a lot of oil and wax, and there are still catalyst fine powder with small particle size, it is easy to cause washing.
  • the filter element of the water precision filter is clogged and the equipment cannot operate normally.
  • the entry of catalyst particles into the stripping tower will also affect the stable operation of the stripping tower, so it is very important to find an efficient method for separation, deoiling and desolidification.
  • the common methods for desolidification and degreasing of wastewater mainly include physical method, chemical method, physical-chemical method and biological method.
  • the physical methods mainly include gravity method, centrifugal separation method, precision filtration method, membrane separation method, etc.
  • Gravity method has poor separation accuracy and cannot remove emulsified oil in washing water; centrifugal separation method is suitable for the separation of fine oil droplets and sub-micron particles. The effect is poor; because the particle size of the MTO washing water is small and contains a small amount of oil wax, it is easy to enter the inside of the filter element pores of the precision filtration device, resulting in blockage of the pores, which is difficult to remove by online backwashing; the membrane separation method has excellent separation effect in recent years.
  • Chemical methods mainly include flocculation method, oxidation method, electrochemical method, etc.
  • the flocculation method has poor treatment effect on emulsified oil and fine particles, and the cost of treatment agents is high, and it is easy to produce secondary pollution; chemical oxidants such as ozone, Fenton reagent, etc. are used.
  • the organic matter in the wastewater can be degraded to improve the biodegradability, but the treatment cost is high.
  • Physical and chemical methods mainly include air flotation method, adsorption method, coagulation method, etc.; air flotation method needs to consume chemicals and occupies a large area; adsorption method has limited adsorption capacity of adsorbent, high cost, and difficult regeneration; coagulation method operation Simple, small footprint, but need to add coagulant, high cost.
  • the biochemical method has low cost, low investment and no secondary pollution, it occupies a large area, and the concentration of pollutants in the methanol-to-olefin wastewater is high and the organic matter is large, which will affect the normal operation of the biochemical tank.
  • Chinese patent application CN104649446A proposes to use three or more multi-channel rotary valves in parallel as filtration and separation units for solid-liquid separation of methanol-to-olefin washing water and quench water, but according to its experimental description Most of the catalyst particles with a particle size of more than 3 ⁇ m are treated, and the catalyst particles below 3 ⁇ m cannot be removed very well. Moreover, as a low-cost and widely used mechanical equipment, the rotary valve is mainly used for feeding, dust removal, and unloading in the world, and basically does not have the function of degreasing the washing water.
  • Chinese patent application CN103951098A proposes to use ultrafiltration membranes to separate and purify washing water, and combine three-phase separators to recover catalysts.
  • the application utilizes a relatively advanced membrane separation technology to treat the washing water and recover the catalyst particles to improve economic benefits.
  • the application shows that the diameter of the membrane used is 5-200 nm, and the treatment of fine particles is relatively fine, but in the process of washing water with high flow rate and high oil content, it is easy to cause the pressure difference to increase and the treatment efficiency to decrease.
  • its filter unit is a series of filter membranes. During backflushing, due to the high solid content and oil content of the concentrate, the series of filter membranes increases the pressure difference step-up, which is not conducive to the stable and continuous operation of the large-flow treatment process.
  • Chinese patent applications CN102093153A and CN101352621A propose to use microcyclone technology to perform microcyclone separation of methanol-to-olefin quench water to remove catalyst particles entrained therein.
  • the micro-cyclone separator has the advantages of wide applicability, low cost, and easy maintenance. Compared with the ordinary cyclone separator with a separation accuracy of 5-10 ⁇ m, the separation efficiency is higher, but for fine particles below 3 ⁇ m, especially the extremely small particles below 1 ⁇ m. Fine particles have the problem of limited separation efficiency, and due to their structural characteristics, it is easy to cause problems such as blockage and high pressure drop, which increases the energy output and the difficulty of cleaning and maintenance in the later period.
  • the washing water contains a large amount of organic oxygen-containing compounds and oil waxes, the separation effect of the micro-cyclone on the oil is limited, and the oil and ultra-fine particles in the waste water bring unstable operation factors to the subsequent stripping process.
  • the present disclosure provides a novel method and device for extending the continuous operation period of the methanol-to-olefin water washing process, thereby solving the problems existing in the prior art.
  • the present disclosure provides a method and a device for extending the continuous operation period of the methanol-to-olefin water washing process, which achieves the purpose of efficiently reducing the oil content and solid content of the washing water, and at the same time extending the stable operation period of the equipment.
  • the method is simple and effective, and solves the technical defects in the prior art that the filtering equipment is easy to block, frequent cleaning, short continuous operation time, and incomplete removal of oil, wax and solid particulate matter in water.
  • the present disclosure provides a method for extending the continuous operation period of a methanol-to-olefin water washing process, the method comprising the following steps:
  • washing water after deoiling by microcyclone is sent to the ebullated bed separator for treatment to remove emulsified oil, dispersed oil and catalyst fine powder in the water, wherein the ebullated bed separator is continuously operated until the operating pressure difference accumulates After reaching 0.05-0.3MPa, backwash with washing water, or add nitrogen to mix backwash, so that the particle bed of the fluidized bed separator is completely fluidized to a boiling state;
  • the method further comprises: (vi) sending part of the washing water treated by the ebullated bed separator to the bottom reboiler of the propylene rectification column of the olefin separation unit as a heat source, and recovering part of the waste heat of the washing water , and return to the washing tower after heat exchange; part of it is sent to the sewage stripping tower for stripping treatment.
  • the working temperature of the methanol-to-olefin washing water is 85°C or higher
  • the content of solid catalyst particles is 0.1-1.0 g/L
  • the average particle size of the solid catalyst particles is 0.5-5 ⁇ m
  • the oil content in the washing water is 200-700 mg/L.
  • the medium used in the particle bed is a polymorphic particle filter material with a particle size of 0.2 mm to 3 mm, wherein the lower the spherical rate and the smaller the particle size, the higher the dirt holding rate; The higher the mold rate and the larger the particle size, the higher the rotation regeneration efficiency.
  • the washing water stock solution enters from the bottom of the ebullated bed separator to drive the particle bed to boil, wherein the backwashing flow rate is 10-20 m/h;
  • the waste is filtered and dehydrated for recycling.
  • the present disclosure provides a device for extending the continuous operation period of a methanol-to-olefin water washing process, the device comprising:
  • Microcyclone separator for microcyclone treatment of methanol-to-olefin wash water to remove free oil from the water
  • the ebullated bed separator connected with the microcyclone separator is used to treat the washing water after degreasing by the microcyclone to remove the emulsified oil, dispersed oil and catalyst fine powder in the water.
  • the device further comprises:
  • the sedimentation tank connected with the microcyclone separator is used to settle the washing water discharged from the microcyclone separator to realize oil-water separation
  • the buffer tank connected with the ebullated bed separator is used to store the washing water purified by the ebullated bed separator;
  • a stripping column connected to the buffer tank for stripping the wash water treated by the ebullated bed separator
  • the bottom reboiler of the propylene rectification column of the olefin separation device connected to the buffer tank is used to use the washing water treated by the ebullated bed separator as a heat source to recover part of the waste heat of the washing water, and/or
  • the filter press unit connected to the ebullated bed separator is used to filter and dehydrate the water-containing waste in the middle and lower layers of the ebullated bed separator for recycling.
  • the fluidized bed separator is a combination of a three-phase separator and a particle bed
  • the medium used in the particle bed is a series combination of multiple sizes and shapes of particle filter media.
  • the rotation intensity of the particles increases under the same flow rate, and the rotation speed reaches 1500 rpm or higher, The regeneration efficiency of the particle bed is improved.
  • the invention adopts the method of combining a microcyclone separator and a fluidized bed separator to carry out desolidification and oil removal treatment on the washing water of methanol to olefins, and combines the design of backwashing to realize particle regeneration and zero-holding pollution;
  • the oil content is below 50mg/L
  • the solid content is below 50mg/L
  • the dust residual rate after backwashing is below 5%; the requirements of high removal efficiency, long operation period, easy maintenance and stable operation of downstream equipment are realized.
  • it realizes the comprehensive treatment of waste liquid, waste gas and waste heat recovery of washing water produced in the regeneration of the purification device, and realizes near-zero emission of pollutants, near-zero landfill of waste, and effective utilization of heat.
  • FIG. 1 is a schematic process flow diagram of a method for extending the continuous operation period of a methanol-to-olefin water washing process according to a preferred embodiment of the present disclosure.
  • FIG. 2 is a schematic process flow diagram of a method for extending the continuous operation period of the methanol-to-olefin water washing process according to another preferred embodiment of the present disclosure.
  • FIG. 3 is a schematic diagram of a processing flow of a washing water purification device for discharging waste water to a sewage treatment plant according to a preferred embodiment of the present disclosure.
  • FIG. 4 is a flow monitoring diagram of using backwash to maintain continuous operation of the equipment in a pilot test according to a preferred embodiment of the present disclosure.
  • FIG. 5 is a schematic diagram of the principle of backwashing of the ebullated bed separator according to a preferred embodiment of the present disclosure.
  • Oil trap 2-1. Oil trap, 2-2. Air flotation tank, 2-3. Biochemical unit, 2-4. Aerated biological filter, 2-5. Sand filter unit.
  • the inventor of the present application has developed the ebullated bed separation technology by studying the movement of fine particles on the microscopic scale, the regulation of arrangement structure, the law of particle aggregation and the regulation of the capture mechanism of particles to the microdispersed phase, using the collision, adsorption and separation of separation media
  • the high-precision interception of the microchannel formed by the medium can effectively remove the fine particles and some oily organic substances in the washing water, and the microchannel separation is different from the membrane separation. Avoid clogging problems with contaminants.
  • microcyclone separation is a A method with low cost, convenient use, wide applicability and effective treatment; compared with ordinary cyclones, the current international standard can generally remove fine catalyst particles above 6 ⁇ m, but for extremely fine particles below 5 ⁇ m.
  • the efficiency is relatively general; the microcyclone separator is strengthened in parallel, and its separation efficiency can be much higher than that of the ordinary cyclone, and the particles below 5 ⁇ m can be separated and recovered;
  • the catalyst content below 3 ⁇ m is not high, but through industrial experiments, it is found that the entrainment of extremely fine catalysts often accelerates the blockage of the separator , which increases the cleaning frequency of the device, and is not conducive to the recycling of recovered wastewater, so it is inspired to develop a deep particle bed filter to separate and treat extremely fine particles and oil in the washing water.
  • the combined process of the two separation technologies of cyclone separation and ebullated bed separation is expected to effectively solve the problems of incomplete separation and easy blockage, frequent cleaning of equipment and short continuous operation period in the existing methanol-to-olefin washing water circulation system.
  • the methanol-to-olefin washing water is pre-separated by a microcyclone; the separated washing water further enters the ebullated bed separator for deep filtration; the degreasing and filtered washing water enters the buffer tank for recycling Or stripping treatment; in which, after the fluidized bed separator is continuously operated until the operating pressure difference accumulates to a certain value, the raw water for washing is passed through the outlet of the fluidized bed separator for backwashing to make the particle medium boil, and the medium rotates at high speed and collides with each other.
  • a method for extending the continuous operation period of a methanol-to-olefin water washing process comprising:
  • the washing water entrained with catalyst particles such as SAPO-34, oil-phase substances such as aromatic hydrocarbons, and reaction gas such as methanol is extracted from the bottom of the washing tower by a centrifugal pump, and firstly, it is pre-separated and deoiled by a microcyclone to remove free oil in the water;
  • the oil-rich wastewater separated by the microcyclone separator is sent to the settling tank, and the oil-water phase in the oil phase is further separated, and the oil phase is used for back refining treatment;
  • the washing water after degreasing by the microcyclone is discharged through the bottom flow of the microcyclone separator, and passed into the fluidized bed filter together with the wastewater separated from the sedimentation tank, and the remaining water is filtered out by the interception and adsorption of the separation medium particles. It is difficult to separate capillary oil (emulsified oil, dispersed oil), etc., and at the same time filter extremely fine catalyst particles in the washing water;
  • the particle speed is maintained above 1500rad/s (revolution/second), and the combination of media with low spherical rate and wide particle size range can increase the speed within a certain range and speed up regeneration;
  • the filter material is returned to the bed, and the backwash liquid and backwash gas entrained with the catalyst are respectively discharged from the top liquid phase and gas phase outlets;
  • the backwash flow rate is adjusted to 50-90 m 3 /h.
  • the flow rate is increased during backwashing, so that the particle medium rotates and collides with the liquid flow, accelerates the removal of pollutants on the surface and in the pores, and the backwash concentrate is removed from the three-phase separator at the top of the particle bed filter.
  • the liquid phase is discharged from the outlet, and after gravity sedimentation, the bottom concentrate can be processed and recovered by dehydration technology such as pressure filtration.
  • the pressure difference rises slowly and is less than 0.1MPa; every 10 hours of operation, the recoil is performed to realize the regeneration of the activity of the filter material, and the change of the operating flow pressure difference after the recoil is consistent with the initial.
  • the degreasing and filtered washing water is temporarily stored in the buffer tank, a part of it is cooled and returned to the washing tower for recycling, and a part is sent to a stripping tower for stripping treatment, and separated out. Purify water and oil phases.
  • the purification method includes a series combination of three separation modes: microcyclone separation, particle bed filtration and subsequent stripping column treatment.
  • the working temperature of the washing water is 85-95°C
  • the solid particles are fine powder of methanol-to-olefin catalyst particles, usually SAPO-34 molecular sieve powder
  • the solid content is 0.1-0.5g/L
  • the average particle size is 0.5 ⁇ 5 ⁇ m.
  • the separation and purification consists of microcyclone separation and deep particle bed separation, wherein microcyclone separation can initially separate larger particles, and particle bed separation removes oil and wax components such as extremely fine particles and aromatic hydrocarbons.
  • the processing capacity of the washing water is 35-65 m 3 /h
  • the backwashing flow rate is 10-20 m/s
  • the particle rotation above 1500 rad/s is realized, and the particle activity regeneration is completed.
  • the backwashing effect is good, the initial backwashing liquid solid concentration reaches 3.2%, and after backwashing for 1 minute, it drops to 287mg/L, and the residual rate of catalyst on the surface of the filter material after backwashing is below 5%, effectively realizing regeneration.
  • the oil content of the washing water is 200-700 mg/L.
  • the oil content in the water is reduced to below 50 mg/L, and the content of suspended solids is reduced to below 50 mg/L.
  • a device for extending the continuous operation period of a methanol-to-olefin water washing process comprising:
  • Microcyclone separator for pre-separation of larger catalyst particles and grease entrained in washing water
  • the settling tank connected with the microcyclone is used to treat the oil-rich wastewater separated by the microcyclone;
  • the fluidized bed separator connected with the microcyclone separator has a built-in deep particle bed filter for secondary purification of the washing water after microcyclone separation. filter and other dehydration devices; and the built-in three-phase separator in the fluidized bed separator, which is used for the separation and recovery of the concentrate and solid filter material during backwashing of the deep particle bed filter;
  • a buffer tank connected to the ebullated bed separator for storing the washing water filtrate to keep the unit in continuous and stable operation;
  • the stripper connected to the buffer tank is used for stripping the washing water after microcyclone separation and deep particle bed filtration.
  • the device is composed of a microcyclone filter and an ebullated bed separator (a three-phase separator and a deep particle bed filter) in series.
  • the pressure loss of the microcyclone separator is 0.15-0.30 MPa
  • the pressure loss of the deep particle bed filter is 0.01-0.30 MPa.
  • the medium of the deep particle bed filter is a multi-size and multi-shape series combination of granular filter materials such as quartz sand, anthracite, nut shell, activated carbon, carbon balls, etc. with a particle size of 0.2 mm to 3 mm.
  • granular filter materials such as quartz sand, anthracite, nut shell, activated carbon, carbon balls, etc.
  • the series combination of 1-2mm anthracite particles and 0.5-1.0mm quartz sand particles and the series combination of 1-2mm quartz sand particles, 0.5-1.0 carbon ball particles and 0.3-0.5mm quartz sand particles.
  • FIG. 1 is a schematic process flow diagram of a method for extending the continuous operation period of a methanol-to-olefin water washing process according to a preferred embodiment of the present disclosure, which is suitable for working conditions with high oil content and low solid content.
  • the methanol-to-olefin reaction gas is discharged from the top outlet of reactor 1-1, and the entrained catalyst particles are sent into quench tower 1-3 for reaction and then sent to water washing tower Washing with water in 1-4, the reaction gas that removes the catalyst flows out of the water washing tower from the top, and olefin is separated; the catalyst of the reaction is discharged into the catalyst regeneration tower 1-2 regeneration by the bottom outlet of the reactor 1-1, and the resulting gas (CO 2 ) etc.) are discharged from the top outlet of the regeneration tower 1-2, and the regenerated catalyst is discharged from the bottom outlet of the regeneration tower 1-2 and returned to the reactor 1-1; the water and the washed catalyst fine particles are
  • a large amount of washing water with entrained grease is discharged from the overflow port and sent to the sedimentation tanks 1-6 for sedimentation to realize the separation of oil and water.
  • the oil of -10 is re-refined together with the slop oil; the washing water with the catalyst and the remaining oil is discharged from the bottom flow outlet and sent to the ebullated bed separator 1-7 for secondary purification; the washing water after deep purification by the particle bed is temporarily stored In the buffer tank 1-8, a part is sent to the stripping tower 1-10 for stripping treatment together with the washing water after the separation of the oil in the sedimentation tank, and a part is sent to the olefin separation device propylene rectification tower bottom reboiler 1-9
  • As a heat source part of the waste heat of the washing water is recovered, and after heat exchange, it is sent to the washing towers 1-4 for recycling; the purified water obtained by the stripping towers 1-10 is recovered; Maintain stable operation during backwashing of the device; when the pressure difference rises to
  • FIG. 2 is a schematic process flow diagram of a method for extending the continuous operation period of the methanol-to-olefin water washing process according to another preferred embodiment of the present disclosure, which is suitable for working conditions with low oil content and high solid content.
  • the sedimentation water after microcyclone separation is also purified by the secondary particle bed as another waste water returned to the washing tower for recycling; Send it to the sedimentation tank; set a sampling port at the water outlet of the buffer tank, when the water sample meets the discharge conditions (petroleum substances ⁇ 20mg/L, COD ⁇ 1200mg/L, BOD ⁇ 5500mg/L), it can be directly discharged without the stripping tower .
  • the process shown in Figure 2 treats the backflush concentrate separately, and can go through a series of processes such as sedimentation, centrifugal separation or drying and dehydration to complete the purification of waste liquid and the recycling of catalysts; its discharge is more green and environmentally friendly.
  • the sewage method can be directly carried out, which greatly reduces the expenditure and energy consumption of the stripping tower.
  • the methanol-to-olefin reaction gas is discharged from the top outlet of the reactor 1-1, and the reaction gas and entrained particles enter the quench tower 1-3 for reaction and then are sent to washing Washing in the tower 1-4
  • the catalyst of the reaction is discharged from the bottom outlet of the reactor 1-1 and sent to the catalyst regeneration tower 1-2 for regeneration, and the resulting gas (CO 2 etc.) is discharged from the top outlet of the regeneration tower 1-2, and the regenerated catalyst It is discharged from the bottom outlet of the regeneration tower 1-2 and returned to the reactor 1-1; olefins are discharged from the top of the washing tower 1-4 to separate the olefins, and the washing water in the tower is pumped out by a centrifugal pump and sent to the microcyclone separator 1-5.
  • the oil is discharged from the overflow port and sent to the settling tank 1-6 for settling to realize the recovery of the slop oil.
  • the solid-containing washing water is discharged from the bottom flow port, and sent to the fluidized bed separator 1-7 together with the water phase in the settling tank. Carry out secondary purification; the washing water and sedimentation water after the deep purification of the particle bed are temporarily stored in the buffer tanks 1-8, and a part is sent to the bottom reboiler 1-9 of the propylene rectification tower of the olefin separation unit as a heat source, and the washing water is carried out.
  • Part of the waste heat is recovered and returned to the washing tower 1-4 after heat exchange for circulation, and a part is sent to the stripping tower 1-10 for stripping treatment;
  • the oil of 1-6 is decontaminated and refined together with the oil;
  • the liquid level of the buffer tank is kept above 1/2, so that the circulating water and the treatment process can be carried out normally during backwashing; when the pressure difference rises to a certain value, switch to the backwashing state , the backflush concentrate is discharged from the liquid phase outlet of the three-phase separator on the upper part of the fluidized bed separator, and settles, and the pressure filtration unit 1-11 is subjected to pressure filtration treatment to realize catalyst recovery, so as to achieve near-zero landfill of waste,
  • the waste water containing trace oil and solids produced by filter press units 1-11 is discharged to the sewage treatment plant.
  • the water up to the standard is discharged to the environment or reused; the backwash gas is discharged from the fluidized bed separator.
  • the water in it is removed by a cyclone deliquor and sent to the torch unit, and the gaseous organic matter carried in the regeneration process of the ebullated bed is burned to achieve near-zero emission of pollutants; after recoil, the particle bed
  • the bottom flow washing water of the microcyclone separator is re-entered from the upper inlet of the fluidized bed separator and switched to the normal working state; when the water sample outside the buffer tank meets the standard (petroleum substances ⁇ 20mg/L, COD ⁇ 1200mg /L, BOD ⁇ 5500mg/L), can be directly discharged without stripper treatment.
  • FIG. 3 is a schematic diagram of a processing flow of a washing water purification device for discharging waste water to a sewage treatment plant according to a preferred embodiment of the present disclosure. As shown in Figure 3, the average flow rate of wastewater discharged from the washing water purification device to the sewage treatment plant is 3t/h.
  • the wastewater from the washing water purification device is first sent to the grease trap 2-1, and the suspended solids, oil and water in the wastewater are used to The suspended solids and grease in the wastewater are initially separated with different specific gravity; the wastewater treated by the oil separator 2-1 is sent to the air flotation tank 2-2, and the suspended solids flocs and small oil droplets in the wastewater are further flocculated and grown, and mixed with The bubbles released by the dissolved air and water combine to form large flocs that rise to the water surface under the action of buoyancy and rising water, thereby further separating oil and solid in the wastewater; Microbial degradation removes COD (chemical oxygen demand), ammonia nitrogen and grease, etc.
  • COD chemical oxygen demand
  • ammonia nitrogen and grease etc.
  • FIG. 4 is a flow monitoring diagram of using backwashing to maintain the continuous operation of the equipment in a pilot test according to a preferred embodiment of the present disclosure, and shows a pilot test in which the ebullated bed separator according to the present invention realizes continuous and stable operation for more than 60 hours through backwashing.
  • Experimental flow changes As shown in Figure 4, within the first 8 hours of continuous operation, the pressure difference increased slowly, and the pressure difference was less than 0.1MPa. After backwashing, the medium activity achieved prominent regeneration, which could achieve stable continuous operation on the basis of ensuring efficient separation.
  • FIG. 5 is a schematic diagram of the principle of backwashing of the ebullated bed separator according to a preferred embodiment of the present disclosure. As shown in Fig. 5, the particles in the bed rotate and collide to realize the removal of pollutants and the regeneration of the medium's channels. In the figure, ⁇ represents the particle rotation speed.
  • the method of the present invention is adopted, and a fluidized bed purification device is used to purify the washing water containing solid catalyst and oil, so as to realize the removal of waste catalyst particles.
  • the methanol-to-olefin washing water is a liquid-solid two-phase mixture.
  • the water contains solid catalyst particles and oil.
  • the main components of the oil are high-concentration refractory aromatic hydrocarbons.
  • the washing water treatment capacity is 35-65 m 3 /h, and the operating temperature is 90 °C, the content of waste catalyst is 0.1 ⁇ 0.5g/L, the average particle size is 2.0 ⁇ m, and the oil content is nearly 200 ⁇ 700mg/L.
  • the heat loss of 1 ton of wastewater is about 270 MJ, and if the external drainage washing water is 160 t/h, the daily heat loss is 1,036,800 MJ, equivalent to 35.4 tons of standard coal per day. Therefore, the currently adopted measures are relatively poor in terms of safety, environmental protection and economy.
  • the diameter of the device is 2.4m and the height is about 6m.
  • a three-phase separator is installed on the top of the device to recover the filter material during backwashing, and at the same time discharge the backwash liquid and backwash nitrogen;
  • the filter material in the bed is 0.2mm ⁇ 3mm Spherical particle filter media such as quartz sand, anthracite, nut shell, activated carbon, alumina particles, carbon balls or ceramic balls, and the shape of the filter media particles can also use irregular shapes such as columnar and tetrahedron, with better effect. It is 0.8 ⁇ 1.5m, and the processing capacity of a single unit is 50m 3 /h. 6 units are used in parallel, 2 units are used in groups, and the backwashing is switched in turn.
  • the methanol-to-olefin washing water containing catalyst fine powder is sent to the microcyclone separator by centrifugal pump for preliminary separation, and then enters the ebullated bed separator group to remove the fine particles and remaining grease in the water;
  • the ebullated bed separator group consists of 6 sets of three groups Work in parallel, 1 standby, run continuously until the pressure difference rises to 0.2MPa, then switch to backwash and forward wash operations in turn, and then continue to run.
  • microcyclone separation, metal membrane, ceramic membrane and bag filtration have been gradually applied in the purification process of methanol to olefin wastewater.
  • the inventor of the present application through domestic field research, found that several methods all have certain deficiencies, resulting in the purification of methanol-to-olefin wastewater, which has always been a major problem that is difficult to solve in the MTO industry.
  • MTO devices more than 10 sets of MTO devices are used for microcyclone and metal membrane, and these two devices are generally operated in series.
  • the microcyclone is used as the primary separation, and the metal membrane is used for deep purification.
  • the separation accuracy of the microcyclone separator is low, and it only has a good separation effect on particles larger than 3 microns, and it is difficult to separate particles smaller than 3 microns. Due to the problem of membrane fouling in metal membrane microfiltration, the membrane flux will be reduced to below 20% of normal within one month of operation, making it difficult to operate normally. Ceramic membrane and bag filter are added in some MTO plant wastewater and technical transformation. Ceramic membranes are effective in filtering fine particles in methanol-to-olefin wastewater, but the equipment cost is high, the pressure across the membrane is high, and the problem of membrane channel blockage will gradually appear after more than one year of operation. Currently, there are 3 sets of MTO wastewater purification used. Due to the low separation accuracy and short life of the bag filter method, the treatment efficiency will be significantly reduced after one year of operation, and it needs to be solved by replacing the filter bag. Only one MTO factory uses it.
  • the ebullated bed separation technology is second only to ceramic membranes in separation efficiency.
  • the filtration channels are formed by the accumulation of loose filter material particles.
  • the filter material particle bed has a large porosity, and the filtered particles can be accommodated through the gaps between the filter materials, so its dirt holding capacity is large, and the backwash frequency is significantly lower than that of surface filtration methods such as metal membranes and ceramic membranes.
  • the pollutants retained in the pore channels can be easily released, and due to the addition of cyclone to strengthen the washing, the pollutants can be easily separated from the surface of the filter material, so the filter material can be regenerated.
  • the effect is better than the traditional depth filter device.
  • it is superior to its traditional anthracite, carbon balls, etc. whose filter materials are low in price, so its equipment investment and maintenance costs are very low.
  • Fluidized bed separation technology is superior to other technologies in terms of equipment investment, loading and unloading costs, operating costs, sewage discharge frequency, and separation energy consumption. Its separation efficiency is second only to that of ceramic membranes and is sufficient for the separation of fine catalyst particles in MTO water systems. But it occupies more space than other technologies.
  • the comprehensive evaluation shows that the fluidized bed separation technology has excellent performance in the purification of MTO wastewater, so it is more suitable for the industrial treatment of MTO wastewater.
  • the invention adopts the method of combining a microcyclone separator and an ebullated bed separator to carry out desolidification and oil removal treatment on the methanol-to-olefin water washing water, and combines the design of the ebullated bed backwashing to realize particle regeneration and zero-holding capacity;
  • the oil content in the washing water is below 50mg/L
  • the solid content rate is below 50mg/L
  • the dust residual rate after backwashing is below 5%; it realizes high removal efficiency, long operation period, easy maintenance and stable operation of downstream equipment. requirements.
  • the washing water as the heat source of the propylene rectification tower bottom reboiler of the olefin separation unit, part of the waste heat recovery is calculated, and the washing water is discharged at 90 °C, and the waste heat is recovered and cooled to 65
  • the heat recovery per ton of wastewater is about 100 MJ
  • the external drainage washing water is calculated at 160 t/h, which saves 384,000 MJ of heat per day, equivalent to 13.1 tons of standard coal per day.
  • the oily and solid washing water is a high-concentration refractory organic wastewater. It was originally discharged to the sewage treatment plant at a flow rate of 160t/h, which increases the cost of sewage treatment.
  • the wastewater discharged to the sewage treatment plant is mainly produced by the filter press unit. Solid waste water, the average discharge is 3t/h.
  • the cost of water treatment per ton is 10 yuan, which can save 12.56 million yuan/year of sewage treatment costs for the original external drainage and washing water.

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Abstract

本公开涉及甲醇制烯烃水洗水工艺连续运行周期延长的方法及装置，提供了一种甲醇制烯烃水洗水工艺连续运行周期延长的方法，该方法包括以下步骤：(i)将甲醇制烯烃水洗水进行微旋流处理；(ii)将经微旋流除油后的水洗水送入沸腾床分离器进行处理；(iii)调节反冲洗流量，以释放拦截的催化剂粉末，清空孔隙纳污量；(iv)将经反冲洗的气液固混合物进行三相分离，所得的滤料返回至颗粒床层，夹带催化剂的反冲洗液和反冲洗气分别外排；以及(v)反冲洗结束后，将沸腾床分离器切换至正常工作状态，颗粒床层完成活性再生，继续运行。还提供了一种甲醇制烯烃水洗水工艺连续运行周期延长的装置。

Description

甲醇制烯烃水洗水工艺连续运行周期延长的方法及装置 技术领域
本公开属于环境污染综合治理领域，涉及一种采用微旋流分离器与沸腾床分离器长周期运行去除甲醇制烯烃工艺水洗水中油脂及催化剂颗粒的方法，尤其适用于分离设备的持续稳定运行，减少了相关设备的后期清洗维护。具体地说，本公开结合旋流分离与颗粒床分离及反冲洗技术，提供了一种甲醇制烯烃水洗水长周期运行的组合分离方法和装置及分离装置再生中产生的废液、废气及水洗水清液余热回收的综合处理方法。
背景技术
甲醇制烯烃，简称MTO(Methanol to Olefins)，是指以甲醇作为原料，通过催化反应制备低碳烯烃的过程。该反应一般通过流化床反应器实现，现用的催化剂多为200nm～20μm的SAPO-34分子筛。反应器中的高温产品气经三级旋风分离器回收催化剂粉末后送往急冷塔，气体经急冷塔冷却至109℃左右后通往水洗塔洗涤，洗涤后再送至烯烃分离单元。受旋风分离器分离精度的限制，部分粒径小于10μm的微细催化剂粉末随产品气送往急冷塔。同时，还有未反应的甲醇、二甲醚等有机含氧化合物以及少量反应的中间产物油蜡类物质(90％以上为芳烃)会随反应气一同进入急冷塔和水洗塔。由于急冷塔操作温度较高，且产品气与急冷水接触时间短，因此急冷塔可将大部分催化剂细粉洗涤下来，而有机含氧化合物及油蜡大部分进入水洗水中。由于反应过程会产生一定量的水，通常水洗塔冷凝下来的废水为含有0.5μm～20μm的SAPO-34分子筛催化剂粉末以及少量甲醇、二甲醚等有机含氧化合物与以芳烃为主的油蜡物质(油含量为200～700mg/L)的高温废水(85～95℃)。
实际生产中，为控制水洗水含油量，在水洗塔内设隔油槽，通过液位控制将水中浮油隔在隔油槽内排出水洗塔。然而，在实际运行中，由于水洗水经隔油后油含量仍有150～300mg/L，造成水洗水循环系统中低温区结蜡严重，水洗水换热器、空冷器及水洗塔塔盘堵塞严重，严重影响了装置的长周期稳定运行，并造成换热系统换热效率低下，需频繁清洗。同时，由于水洗水中的油存在一定的乳化，造成旋流除油器对水中油蜡脱除不彻底；并且由于水中含油蜡较多，同时仍存在小 粒径的催化剂细粉，极易造成水洗水精密过滤器滤芯堵塞，设备无法正常运行。此外催化剂颗粒物进入气提塔内亦会影响气提塔的稳定运行，故寻找高效的分离脱油脱固方法十分重要。
目前常见的废水脱固除油方法主要有物理法、化学法、物理化学法和生物法。其中物理法主要有重力法、离心分离法、精密过滤法、膜分离法等，重力法分离精度差，且无法去除水洗水中的乳化油；离心分离法对于细小油滴和亚微米级的颗粒分离效果较差；由于MTO水洗水中颗粒粒径小，并含有少量油蜡，易进入精密过滤装置的滤芯孔道内部，造成孔道堵塞，难以通过在线反冲洗去除；膜分离法由于其分离效果优良近年来虽得到广泛应用，但由于MTO水洗水固含量和油含量较高，存在易堵塞、维护代价大及成本高等缺点。化学法主要有絮凝法、氧化法、电化学法等，絮凝法对乳化油及细小颗粒物的处理效果较差，且处理药剂成本高、易产生二次污染；用化学氧化剂如臭氧、Fenton试剂等可降解废水中的有机物以提高可生化性，但处理成本较高；电絮凝法需消耗大量盐类辅助药剂且耗电量高，运行费用较高。物理化学法主要有气浮法、吸附法、混凝法等；气浮法需消耗药剂且占地面积较大；吸附法的吸附剂吸附容量有限，且成本高，再生困难；混凝法操作简单，占地面积小，但需添加混凝剂，成本高。生化法虽成本低，投资少，无二次污染，但占地面积大，且甲醇制烯烃废水中污染物浓度较高，有机物成分多，会影响生化池的正常运行。
针对甲醇制烯烃水洗水脱固除油工艺，中国专利申请CN104649446A提出利用三个以上多流道旋转阀并联为过滤分离单元对甲醇制烯烃水洗水和急冷水进行固液分离，但据其实验描述多为处理粒径3μm以上的催化剂颗粒，对3μm以下催化剂颗粒并不能起到很好的去除效果。且旋转阀作为一个造价低廉，应用广泛的机械设备，目前国际上主要有给料、除尘、卸料等应用，基本不具备对水洗水进行除油处理的功能。
中国专利申请CN103951098A提出利用超滤膜对水洗水进行分离净化，并结合三相分离器回收催化剂。该申请利用了较为先进的膜分离技术对水洗水进行处理并回收了催化剂颗粒以提高经济效益。但该申请中显示所用膜径为5～200nm，对微细颗粒的处理较为精细，但在大流量的含油量很高的水洗水处理过程中极易引起压差升高，处理效率降低。且其过滤单元为滤膜的串联，在反冲时由于浓液固含率及油含量很高，串联的滤膜加大了压差的递升，不利于大流量处理过程的 稳定连续运行。
中国专利申请CN102093153A及CN101352621A提出利用微旋流技术对甲醇制烯烃急冷水进行微旋流分离，以除去其中夹带的催化剂颗粒。微旋流分离器具有适用性广、造价低廉、易维护等优点，对比分离精度为5-10μm的普通旋流分离器分离效率更高，但对3μm以下的微细颗粒，尤其是1μm以下的极细颗粒存在分离效率有限的问题，且由于其结构特点易造成堵塞，高压降等问题，加大了能耗输出以及后期的清理维护难度。加之水洗水中含有大量有机含氧化合物及油蜡，微旋流对油分的分离效果有限，废水中的油脂及极细颗粒对后续的汽提工序中的带来不稳定运行因素。
综上，由于传统物理法因处理成本高或处理效果差，化学法因需消耗药剂造成二次污染、处理后水回用困难，物理化学法需消耗药剂且运行成本高，生化法处理速度慢且活性污泥适应性差，都难以满足甲醇制烯烃高浓含油含固废水处理的需求，因此亟需一种简单有效，解决现有方法分离效果不佳的处理工艺。
发明内容
本公开提供了一种新颖的甲醇制烯烃水洗水工艺连续运行周期延长的方法及装置，从而解决了现有技术中存在的问题。
本公开提供了一种甲醇制烯烃水洗水工艺连续运行周期延长的方法及装置，达到了高效降低水洗水油含量、固含量，同时延长设备稳定运行周期的目的。该方法简单有效，解决了现有工艺中存在的过滤设备易堵塞、频繁清洗、连续运行时间短且水中油蜡及固体颗粒物去除不彻底的技术缺陷。
一方面，本公开提供了一种甲醇制烯烃水洗水工艺连续运行周期延长的方法，该方法包括以下步骤：
(i)将甲醇制烯烃水洗水进行微旋流处理，以去除水中的游离油；
(ii)将经微旋流除油后的水洗水送入沸腾床分离器进行处理，以去除水中的乳化油、分散油和催化剂细粉，其中，沸腾床分离器连续运行至操作压差累积至0.05～0.3MPa后，通入水洗水反冲洗，或者加入氮气混合反冲洗，使沸腾床分离器的颗粒床层完全流化至沸腾状；
(iii)调节反冲洗流量至50～90m 3/h，以释放拦截的催化剂粉末，清空孔隙纳污量；
(iv)将经反冲洗的气液固混合物进行三相分离，所得的滤料返回至颗粒床层，夹带催化剂的反冲洗液和反冲洗气分别外排；以及
(v)反冲洗结束后，将沸腾床分离器切换至正常工作状态，颗粒床层完成活性再生，继续运行。
在一个优选的实施方式中，该方法还包括：(vi)将经沸腾床分离器处理的水洗水部分送至烯烃分离装置丙烯精馏塔底重沸器作为热源，进行水洗水的部分余热回收，换热后返回水洗塔；部分送至污水汽提塔进行汽提处理。
在另一个优选的实施方式中，所述甲醇制烯烃水洗水的工作温度为85℃或更高，固体催化剂颗粒的含量为0.1～1.0g/L，固体催化剂颗粒的平均粒径为0.5～5μm，水洗水中的油含量为200～700mg/L。
在另一个优选的实施方式中，在经沸腾床分离器处理后，水洗水中油相的含水量降至10％以下，油含量降至30mg/L以下，固体悬浮物含量降至20mg/L以下，分离精度为D 85＝0.1μm。
在另一个优选的实施方式中，颗粒床层中使用的媒介为粒径为0.2mm～3mm的多形态颗粒滤料，其中球型率越低、粒径越小，纳污率越高；球型率越高、粒径越大，自转再生效率越高。
在另一个优选的实施方式中，水洗水原液从沸腾床分离器底部进入带动颗粒床层沸腾，其中反冲洗流速为10～20m/h；反冲洗浓液排出后先重力沉降，然后将下层含水废料进行压滤脱水，以作回收处理。
另一方面，本公开提供了一种甲醇制烯烃水洗水工艺连续运行周期延长的装置，该装置包括：
微旋流分离器，用于将甲醇制烯烃水洗水进行微旋流处理，以去除水中的游离油；以及
与微旋流分离器连接的沸腾床分离器，用于处理经微旋流除油后的水洗水，以去除水中的乳化油、分散油和催化剂细粉。
在一个优选的实施方式中，该装置还包括：
与微旋流分离器连接的沉降罐，用于对微旋流分离器排出的水洗水进行沉降，实现油水分离；
与沸腾床分离器连接的缓冲罐，用于存储经沸腾床分离器净化后的水洗水；
与缓冲罐连接的气提塔，用于将经沸腾床分离器处理的水洗水进行汽提处理； 以及
与缓冲罐连接的烯烃分离装置丙烯精馏塔底重沸器，用于将经沸腾床分离器处理的水洗水作为热源，进行水洗水的部分余热回收，和/或
与沸腾床分离器连接的压滤单元，用于将沸腾床分离器中下层含水废料进行压滤脱水，以作回收处理。
在一个优选的实施方式中，所述沸腾床分离器为三相分离器和颗粒床层的组合，颗粒床层中使用的媒介为颗粒滤料的多尺寸多形状串联组合。
在另一个优选的实施方式中，所述媒介中选用的颗粒，其粒径梯度变化50％或更大后，同流量下颗粒自转强度增大，自转转速达1500转/秒或更高，颗粒床层再生效率提高。
有益效果：
本发明采用微旋流分离器和沸腾床分离器组合的方法对甲醇制烯烃水洗水进行脱固除油处理，结合反冲洗设计实现颗粒再生与纳污量清零；较佳地达到降低水洗水中含油率至50mg/L以下，固含率至50mg/L以下，反冲洗后粉尘残留率5％以下的要求；实现了脱除效率高、运行周期长、便于维护及便于下游设备稳定运作的要求；同时实现了净化装置再生中产生的废液、废气及水洗水清液余热回收的综合处理，实现污染物近零排放、废弃物近零填埋、热量有效利用。
附图说明
附图是用以提供对本公开的进一步理解的，它只是构成本说明书的一部分以进一步解释本公开，并不构成对本公开的限制。
图1是根据本公开的一个优选实施方式的甲醇制烯烃水洗水工艺连续运行周期延长的方法的工艺流程示意图。
图2是根据本公开的另一个优选实施方式的甲醇制烯烃水洗水工艺连续运行周期延长的方法的工艺流程示意图。
图3是根据本公开的一个优选实施方式的水洗水净化装置外排废水至污水处理场的处理流程示意图。
图4是根据本公开的一个优选实施方式的利用反冲洗维持设备小试试验连续运行的流量监控图。
图5是根据本公开的一个优选实施方式的沸腾床分离器反冲洗时的原理示意图。
图中，各个附图标记表示如下：
1-1.反应器，1-2.再生器，1-3.急冷塔，1-4.水洗塔，1-5.微旋流分离器，1-6.沉降罐，1-7.沸腾床分离器，1-8.缓冲罐，1-9.烯烃分离装置丙烯精馏塔底重沸器，1-10.汽提塔，1-11.压滤单元；
2-1.隔油池，2-2.气浮池，2-3.生化单元，2-4.曝气生物滤池，2-5.砂滤单元。
具体实施方式
本申请的发明人通过研究微细颗粒在微观尺度上的运动、排列结构调控、颗粒聚并规律以及调控颗粒对微分散相的捕获机理开发了沸腾床分离技术，利用分离媒质的碰撞、吸附及分离媒质形成的微通道的高精度截留作用，可有效去除水洗水中的微细颗粒物和部分油类有机物，且微通道分离不同于膜分离，微分离通道不固定、通道长，容污量大，可有效避免污染物的堵塞问题。对甲醇制烯烃水洗水这类操作流量大、含油率高、固含量较低且夹带催化剂微细颗粒粒径小(通常为1-10μm)的易堵塞难稳定运行的处理体系，微旋流分离是一种造价低廉经济、使用方便、适用性广且处理有效的方法；相比于普通旋流器，目前国际水准，其一般可去除6μm以上的微细催化剂颗粒，但是对于5μm以下的极细颗粒去除效率较为一般；微旋流分离器通过并联加强，其分离效率可大大高于普通旋流器，对5μm以下颗粒进行分离回收；但由于水洗水含油率高，油分较粘，存在附着为微旋流分离器内壁分离不佳的情况，且水洗水中夹带催化剂颗粒多为1～10μm，其中3μm以下催化剂含量不高，但通过工业实验实践中发现，极细催化剂的夹带往往会加快分离器的堵塞，增加了装置的清洗频率，且不利于回收废水的循环利用，因此启发了开发深层颗粒床过滤器对水洗水中极细颗粒和油分进行分离处理。旋流分离和沸腾床分离两种分离技术的组合工艺有望有效解决现有甲醇制烯烃水洗水循环系统存在的分离不彻底易堵塞、设备频繁清洗、连续运行周期短的问题。
本发明的技术构思如下：
通过微旋流分离器对甲醇制烯烃水洗水进行预分离；经分离后的水洗水进一步进入沸腾床分离器进行深层过滤；经除油和过滤后的水洗水进入缓冲罐中，以进行循环利用或汽提处理；其中，沸腾床分离器连续运行至操作压差累积至一定 值后，从沸腾床分离器出口通入水洗原水进行反冲洗使颗粒媒介呈沸腾状，媒介发生高速自转与相互碰撞，实现拦截物的释放与媒介过滤活性的再生，重新提升沸腾床分离器的纳污量，从而大大减少设备的堵塞及反复清洗维护，水洗水净化处理过程继续稳定运行。
在本公开的第一方面，提供了一种甲醇制烯烃水洗水工艺连续运行周期延长的方法，该方法包括：
夹带SAPO-34等催化剂颗粒、芳烃等油相物及甲醇等反应气的水洗水通过离心泵从水洗塔底抽出，首先通过微旋流分离器进行预分离除油，以去除水中的游离油；
将微旋流分离器分离出的富油废水送至沉降罐，进一步分离油相中的油水相，油相用于回炼处理；
经微旋流除油后的水洗水经微旋流分离器底流排出，和沉降罐里分离出的废水一同通入沸腾床过滤器，利用分离媒质颗粒的拦截、吸附等作用滤除水中剩余的难分离毛细油(乳化油、分散油)等，同时过滤水洗水中的极细催化剂粉粒；
当沸腾床过滤器中颗粒床压差累积至一定值后，切换至反冲洗状态，将旋流除油后的水洗水反向由沸腾床过滤器的原水出口混合氮气一同通入对床内滤料进行反冲洗，使滤料呈沸腾状态；
调节反冲流量，使得滤料充分自转与碰撞，释放孔道吸附空间，并加速滤料间拦截物和表面污染物的脱除；
通过不同滤料媒介的分级组合，使颗粒转速维持在1500rad/s(转/秒)以上，球型率低、粒径范围广的媒介组合可在一定范围内提高转速，加快再生；
反冲洗的气液固混合物通过三相分离器后，滤料返回至床层，夹带催化剂的反冲洗液和反冲洗气分别由顶部液相、气相出口外排出；以及
反冲洗一段时间后，切换至工作过滤状态，反冲排放口关闭。
较佳地，调节反冲洗流量至50～90m 3/h。
较佳地，反冲洗时增大流量，使颗粒媒介在液流带动下发生自转与碰撞，加速表面及孔道内污染物的脱除，反冲洗的浓液从颗粒床过滤器顶部三相分离器的液相出口排出，经过重力沉降后可通过压滤等脱水技术对底部浓液进行处理回收。
较佳地，连续运行前8小时内，压差升高缓慢且小于0.1MPa；每运行10小时反冲1次，实现滤料活性再生，反冲后运行流量压差变化与初始一致。
较佳地，在除油脱固过程中，经除油和过滤后的水洗水暂存在缓冲罐中，一部分经冷却后返回水洗塔循环利用，一部分送至气提塔进行汽提处理，分离出净化水和油相。
较佳地，所述净化方法包括微旋流分离、颗粒床过滤以及后续气提塔处理三种分离方式的串联结合。
较佳地，所述水洗水的工作温度为85～95℃，固体颗粒为甲醇制烯烃催化剂颗粒细粉，通常为SAPO-34分子筛粉末，固含量为0.1-0.5g/L，平均粒径为0.5～5μm。
较佳地，所述分离净化由微旋流分离和深层颗粒床分离组成，其中微旋流分离可初步分离较大颗粒，颗粒床分离去除极细颗粒及芳烃等油蜡成分。
较佳地，所述水洗水处理量为35～65m 3/h，反冲洗流速达10～20m/s，实现1500rad/s以上的颗粒自转，完成颗粒活性再生。
较佳地，所述反冲洗效果良好，初始反洗液固体浓度达3.2％，反洗1min后降至287mg/L，反洗后滤料表面催化剂残留率在5％以下，有效实现再生。
较佳地，水洗水含油率为200～700mg/L，在经过旋流除油及深层机械过滤组合净化后，水中油含量降至50mg/L以下，固体悬浮物含量降至50mg/L以下，沸腾床分离精度为D 85＝0.1μm。
在本公开的第二方面，提供了一种甲醇制烯烃水洗水工艺连续运行周期延长的装置，该装置包括：
微旋流分离器，用于对水洗水中夹带的较大催化剂颗粒和油脂进行预分离；
与微旋流分离器连接的沉降罐，用于处理经微旋流器分离后的富油废水；
与微旋流分离器连接的沸腾床分离器，其内置深层颗粒床过滤器，用于对经微旋流分离后的水洗水进行二级净化，可与氮气入口、沉降罐、缓冲罐及压滤机等脱水装置连接；以及沸腾床分离器内置的三相分离器，用于对深层颗粒床过滤器反冲洗时浓液及固体滤料的分离回收；
与沸腾床分离器连接的缓冲罐，用于储存水洗水过滤液，使装置处于连续稳定运行状态；以及
与缓冲罐连接的汽提塔，用于对经微旋流分离及深层颗粒床过滤后的水洗水进行汽提处理。
较佳地，所述装置由微旋流过滤器和沸腾床分离器(三相分离器与深层颗粒床 过滤器)串联组成。
较佳地，所述微旋流分离器的压力损失为0.15-0.30MPa，深层颗粒床过滤器的压力损失为0.01-0.30MPa。
较佳地，所述深层颗粒床过滤器的媒介为粒径在0.2mm～3mm的石英砂、无烟煤、果壳、活性炭、碳球等颗粒滤料的多尺寸多形状的串联组合，例如，可利用1-2mm无烟煤颗粒与0.5-1.0mm石英砂颗粒的串联组合，1-2mm石英砂颗粒、0.5-1.0碳球颗粒及0.3-0.5mm石英砂颗粒的串联组合等。
以下参看附图。
图1是根据本公开的一个优选实施方式的甲醇制烯烃水洗水工艺连续运行周期延长的方法的工艺流程示意图，适用于油含量较高，固含量较低的工况。如图1所示，甲醇送入反应器1-1中反应后，甲醇制烯烃反应气从反应器1-1顶部出口排出，夹带催化剂颗粒等进入急冷塔1-3中反应后送入水洗塔1-4中水洗，脱除催化剂的反应气从上方出水洗塔，去烯烃分离；反应的催化剂由反应器1-1底部出口排出送入催化剂再生塔1-2再生，所得的气体(CO 2等)由再生塔1-2顶部出口排出，再生的催化剂由再生塔1-2底部出口排出返回反应器1-1；水和洗出的催化剂细颗粒从水洗塔底排出，即水洗水；水洗水由离心泵抽出送往微旋流分离器1-5，大量夹带油脂的水洗水从溢流口排出，被送往沉降罐1-6进行沉降，实现油水分离，并与来自汽提塔1-10的油一同进行污油回炼；夹带催化剂和剩余油脂的水洗水从底流口排出，被送往沸腾床分离器1-7进行二级净化；经颗粒床深层净化后的水洗水先暂存在缓冲罐1-8中，一部分和经沉降罐分离油分后的水洗水一同被送往气提塔1-10进行汽提处理，一部分送至烯烃分离装置丙烯精馏塔底重沸器1-9作为热源，进行水洗水的部分余热回收，换热后送往水洗塔1-4进行循环利用；汽提塔1-10得到的净化水回收；期间缓冲罐液位稳定在1/2以上，以在装置反冲洗时维持稳定运行；当压差升至一定值后，切换至反冲状态，微旋流分离器底流水洗水从沸腾床分离器的原水出口与氮气一同由底部输入，使颗粒呈沸腾状成分自转并碰撞实现再生，反冲浓液从沸腾床分离器上部的三相分离器液相出口排出，送往沉降罐1-6进行分离；反冲洗气由沸腾床分离器1-7排出后经一个旋流脱液罐脱除其中的水分去往火炬单元，燃烧沸腾床再生过程中携持出的气体有机物，以实现污染物的近零排放；反冲完毕，颗粒床滤料再生完成，微旋流器底流水洗 水重新由沸腾床分离器1-7上入口输入，切换至正常工作状态。
图2是根据本公开的另一个优选实施方式的甲醇制烯烃水洗水工艺连续运行周期延长的方法的工艺流程示意图，适用于油含量较低，固含量较高的工况。与图1所示流程不同的是，微旋流分离后的沉降水亦进行二次颗粒床净化，以作为另一股返回水洗塔循环利用的废水；反冲洗时沸腾床浓液单独处理，不送往沉降罐；在缓冲罐出水口设置取样口，当水样满足排放条件时(石油类物质≤20mg/L，COD≤1200mg/L，BOD≤5500mg/L)，可不经气提塔直接排放。
相对于图1的流程，图2的流程对反冲浓液单独处理，可经过沉降，离心分离或干燥脱水等一系列工艺，完成废液的净化以及催化剂的回收利用；其排出物更加绿色环保；同时当水样合格时可直接进行污水方法，大大减少使用气提塔的开支与能耗。
如图2所示，甲醇送入反应器1-1中反应后，甲醇制烯烃反应气从反应器1-1顶部出口排出，反应气及夹带颗粒进入急冷塔1-3中反应后送入水洗塔1-4中水洗，反应的催化剂由反应器1-1底部出口排出送入催化剂再生塔1-2再生，所得的气体(CO 2等)由再生塔1-2顶部出口排出，再生的催化剂由再生塔1-2底部出口排出返回反应器1-1；烯烃等从水洗塔1-4上方排出去烯烃分离，塔内水洗水由离心泵抽出送往微旋流分离器1-5，富油从溢流口排出，被送往沉降罐1-6进行沉降以实现污油回炼，含固水洗水从底流口排出，和沉降罐中水相一同被送往沸腾床分离器1-7进行二级净化；经颗粒床深层净化后的水洗水和沉降水一起暂存在缓冲罐1-8里，一部分送至烯烃分离装置丙烯精馏塔底重沸器1-9作为热源，进行水洗水的部分余热回收，换热后返回水洗塔1-4循环，一部分被送往气提塔1-10进行汽提处理；汽提塔1-10得到的净化水回收，得到的油与来自沉降罐1-6的油一同去污油回炼；缓冲罐液位保持1/2以上，使得反冲洗时，循环水和处理过程可正常进行；当压差升至一定值后，切换至反冲状态，反冲浓液从沸腾床分离器上部的三相分离器液相出口排出，进行沉降，去压滤单元1-11做压滤处理，实现催化剂回收，以实现废弃物的近零填埋，压滤单元1-11产生的含微量油、固的废水排往污水处理场，去除废水中的有机物和悬浮物后，达标水外排至环境中或回用；反冲洗气由沸腾床分离器1-7排出后经一个旋流脱液罐脱除其中的水分去往火炬单元，燃烧沸腾床再生过程中携持出的气体有机物，以实现污染物的近零排放；反冲完毕，颗粒床滤料再生完成，微旋流分离器底流水洗水重新由沸腾床分 离器上方入口输入，切换至正常工作状态；当缓冲罐外水样取样符合标准时(石油类物质≤20mg/L，COD≤1200mg/L，BOD≤5500mg/L)，可直接外排，不需要汽提塔处理。
图3是根据本公开的一个优选实施方式的水洗水净化装置外排废水至污水处理场的处理流程示意图。如图3所示，水洗水净化装置外排至污水处理场的废水平均流量为3t/h，水洗水净化装置废水先送至隔油池2-1，利用废水中悬浮物、油和水的比重不同初步分离废水中的悬浮物和油脂；经隔油池2-1处理后的废水送至气浮池2-2，废水中的悬浮物絮体和细小油滴等进一步絮凝长大，并与溶气水释放的气泡相结合，在浮力和上升水流的作用下，形成大的絮团上升至水面，从而使废水中油固进一步分离；气浮处理后的废水送至生化单元2-3，利用微生物降解作用去除废水中的COD(化学需氧量)、氨氮和油脂等；随后送至曝气生物滤池2-4，利用滤池中滤料表面生物膜的氧化降解作用及滤料截留作用，进一步去除废水中的COD、氨氮、油脂和悬浮物等；最后送至砂滤单元2-5，深度去除废水中的悬浮物后外排水或回用，隔油池2-1、气浮池2-2、生化单元2-3、曝气生物滤池2-4和砂滤单元2-5底部油泥排出。
图4是根据本公开的一个优选实施方式的利用反冲洗维持设备小试试验连续运行的流量监控图，示出了根据本发明的沸腾床分离器通过反冲洗实现连续稳定运行60h以上的小试实验的流量变化。如图4所示，连续运行前8小时内，压差升高缓慢，压差＜0.1MPa，进行反冲洗后，媒介活性实现突出性再生，可在保证高效分离基础上实现稳定的连续运行。
图5是根据本公开的一个优选实施方式的沸腾床分离器反冲洗时的原理示意图。如图5所示，床内颗粒发生自转与碰撞，实现污染物的脱除及媒介的孔道再生，图中ω表示颗粒自转速度。
实施例
下面结合具体的实施例进一步阐述本发明。但是，应该明白，这些实施例仅用于说明本发明而不构成对本发明范围的限制。下列实施例中未注明具体条件的试验方法，通常按照常规条件，或按照制造厂商所建议的条件。除非另有说明，所有的百分比和份数按重量计。
实施例1：
1.实施概况
在一个180万吨/年甲醇制烯烃工艺过程中，采用本发明的方法，采用沸腾床净化装置，对含有固体催化剂及油分的水洗水进行净化，实现废催化剂微粒的脱除。
2.物料性质及处理方式
甲醇制烯烃水洗水为液固两相混合物，水中含有固体催化剂颗粒和油，油类的主要成分为高浓度难降解芳烃类有机物；水洗水处理量为35～65m 3/h，操作温度为90℃，废催化剂含量为0.1～0.5g/L，平均粒径为2.0μm，油含量近200～700mg/L。
在研究的180万吨/年甲醇制烯烃工艺过程中，目前采取的主要措施是以160t/h流量连续外排水洗水并补充新鲜水来平衡水洗水中固含量和油含量，且连续注入二甲苯以缓解催化剂和油类有机物的沉积堵塞。此类措施虽可以缓解甲醇制烯烃水系统堵塞，但耗水量大，经济性差，并增加下游污水汽提塔负荷，且外排废水热量难以利用。按照90℃水洗水外排，冷却至常温25℃时，1吨废水损失热量约270兆焦耳，以外排水洗水160t/h计算，每天损失热量1036800兆焦耳，折合标煤35.4吨/天。因此，目前采取的措施安全、环保、经济性均较差。
3.沸腾床净化装置
该装置直径为2.4m，高度约为6m，装置顶部安装三相分离器，用于反冲洗时回收滤料，同时将反冲洗液和反冲洗氮气外排；床内滤料为0.2mm～3mm的石英砂、无烟煤、果壳、活性炭、氧化铝颗粒、碳球或陶瓷球等球形颗粒滤料，其中滤料颗粒形状亦可使用柱状、四面体等不规则形状，效果更佳，床层高度为0.8～1.5m，单台处理量为50m 3/h，6台并联使用，2台一组，轮流切换反冲洗。
4.实施过程
含催化剂细粉的甲醇制烯烃水洗水由离心泵送至微旋流分离器初步分离，继而进入沸腾床分离器组，脱除水中细颗粒物和剩余油脂；沸腾床分离器组为6台三组并联工作，1台备用，连续运行至压差升高至0.2MPa后，轮流切换至反冲洗、 正洗操作，随后继续运行。
5.实验结果
具体分离情况如下表1所示：
表1：分离参数
Figure PCTCN2020115855-appb-000001
由表1可见，旋流分离和沸腾床分离串联装置对甲醇制烯烃水洗水中颗粒物和油脂具有优良的分离效果，且经反冲洗沸腾再生后，颗粒活性得到较佳提升。
6.技术效果
近年来，微旋流分离、金属膜、陶瓷膜、袋式过滤逐渐应用于甲醇制烯烃废水的净化流程中。本申请的发明人通过国内实地调研，发现几种方法均存在一定的不足，从而导致甲醇制烯烃废水净化一直是MTO行业中难以解决的重大问题。其中微旋流器、金属膜应用超过10套MTO装置，并且这两种设备一般串联操作，微旋流器作为初级分离，金属膜进行深度净化。微旋流分离器分离精度较低，仅对大于3微米颗粒有较好的分离效果，对于小于3微米的颗粒很难分离。金属膜微滤因为膜污染的问题，在运行1个月内膜通量就会降低至正常的20％以下，难以正常运行。陶瓷膜、袋式过滤在部分MTO厂废水及技术改造中增设。陶瓷膜过滤甲醇制烯烃废水中细颗粒物效果较好，但设备成本高，过膜压力高，并且膜通道堵塞的问题也会在运行超过1年后逐渐显现，目前有3套MTO废水净化采用。袋式过滤法由于分离精度低、寿命短，处理效率会在运行一年后显著降低并 需要通过更换滤袋解决，只有1家MTO工厂使用。
沸腾床分离技术相比于已应用的几种技术，其分离效率仅次于陶瓷膜，但由于其采用的原理为深层过滤，其过滤孔道是由松散的滤料颗粒堆积而成的，其孔道可变，从原理上就避免了金属膜或陶瓷膜污染堵塞的问题。滤料颗粒床有着较大的空隙率，并且通过滤料间的空隙容纳滤除的颗粒物，因此其容污量大，反洗频率也显著低于金属膜、陶瓷膜这种表层过滤方法。同时，由于其孔道可变，被滞留在孔道内的污染物可以很容易地释放出来，并由于加入了旋流强化洗涤，使污染物可以很容易地从滤料表面脱离，因此其滤料再生效果优于传统深层过滤装置。此外，优于其滤料为价格低廉的传统无烟煤、碳球等，因此其设备投资及维护费用很低。
几种甲醇制烯烃废水处理技术在工业应用中的比较(按处理能力200m 3/h)如下表2所示。沸腾床分离技术在设备投资、装卸费、运行成本、污水排放频率、分离能耗等方面均优于其他几种技术。其分离效率仅次于陶瓷膜，对于MTO水体系中细小催化剂颗粒的分离是足够的。但比其他技术占有更大的空间。综合评价表明，沸腾床分离技术在MTO废水净化方面具有优异的性能，因此其更适合于MTO废水的工业化处理。
表2：不同MTO废水净化技术的比较
Figure PCTCN2020115855-appb-000002
本发明采用微旋流分离器和沸腾床分离器组合的方法对甲醇制烯烃水洗水进行脱固除油处理，结合沸腾床反冲洗设计实现颗粒再生与纳污量清零；较佳地达到降低水洗水中含油量至50mg/L以下，固含率至50mg/L以下，反冲洗后粉尘残留率5％以下的要求；实现了脱除效率高、运行周期长、便于维护及便于下游 设备稳定运作的要求。同时实现了水的循环利用以及进一步的污油回炼、催化剂的浓缩回收、再生废气的无害化处理和水洗水的部分余热回收，实现甲醇制烯烃水洗水的综合治理。且可取消原来的160t/h的水洗水外排，根据水洗水作为烯烃分离单元的丙烯精馏塔底重沸器热源进行部分余热回收计算，按照90℃水洗水外排，余热回收冷却至65℃时，吨废水回收热量约100兆焦耳，以外排水洗水160t/h计算，每天节约热量384000兆焦耳，折合标煤13.1吨/天。而且，含油含固水洗水属高浓度难降解有机废水，原以160t/h流量外排至污水处理场，增加污水处理费用，现排至污水处理场废水主要为压滤单元产生的含微量油固的废水，平均外排量为3t/h。按吨水处理成本为10元，可节约原外排水洗水的污水处理费用1256万元/年。
上述所列的实施例仅仅是本公开的较佳实施例，并非用来限定本公开的实施范围。即凡依据本申请专利范围的内容所作的等效变化和修饰，都应为本公开的技术范畴。
在本公开提及的所有文献都在本申请中引用作为参考，就如同每一篇文献被单独引用作为参考那样。此外应理解，在阅读了本公开的上述讲授内容之后，本领域技术人员可以对本公开作各种改动或修改，这些等价形式同样落于本申请所附权利要求书所限定的范围。

Claims (10)

  1. 一种甲醇制烯烃水洗水工艺连续运行周期延长的方法，该方法包括以下步骤：
    (i)将甲醇制烯烃水洗水进行微旋流处理，以去除水中的游离油；
    (ii)将经微旋流除油后的水洗水送入沸腾床分离器进行处理，以去除水中的乳化油、分散油和催化剂细粉，其中，沸腾床分离器连续运行至操作压差累积至0.05～0.3MPa后，通入水洗水反冲洗，或者加入氮气混合反冲洗，使沸腾床分离器的颗粒床层完全流化至沸腾状；
    (iii)调节反冲洗流量至50～90m 3/h，以释放拦截的催化剂粉末，清空孔隙纳污量；
    (iv)将经反冲洗的气液固混合物进行三相分离，所得的滤料返回至颗粒床层，夹带催化剂的反冲洗液和反冲洗气分别外排；以及
    (v)反冲洗结束后，将沸腾床分离器切换至正常工作状态，颗粒床层完成活性再生，继续运行。
  2. 如权利要求1所述的方法，其特征在于，该方法还包括：(vi)将经沸腾床分离器处理的水洗水部分送至烯烃分离装置丙烯精馏塔底重沸器作为热源，进行水洗水的部分余热回收，换热后返回水洗塔；部分送至污水汽提塔进行汽提处理。
  3. 如权利要求1或2所述的方法，其特征在于，所述甲醇制烯烃水洗水的工作温度为85℃或更高，固体催化剂颗粒的含量为0.1～1.0g/L，固体催化剂颗粒的平均粒径为0.5～5μm，水洗水中的油含量为200～700mg/L。
  4. 如权利要求3所述的方法，其特征在于，在经沸腾床分离器处理后，水洗水中油相的含水量降至10％以下，油含量降至30mg/L以下，固体悬浮物含量降至20mg/L以下，分离精度为D 85＝0.1μm。
  5. 如权利要求1或2所述的方法，其特征在于，颗粒床层中使用的媒介为粒径为0.2mm～3mm的多形态颗粒滤料，其中球型率越低、粒径越小，纳污率越高；球型率越高、粒径越大，自转再生效率越高。
  6. 如权利要求1或2所述的方法，其特征在于，水洗水原液从沸腾床分离器底部进入带动颗粒床层沸腾，其中反冲洗流速为10～20m/h；反冲洗浓液排出后先重力沉降，然后将下层含水废料进行压滤脱水，以作回收处理。
  7. 一种甲醇制烯烃水洗水工艺连续运行周期延长的装置，该装置包括：
    微旋流分离器(1-5)，用于将甲醇制烯烃水洗水进行微旋流处理，以去除水中的游离油；以及
    与微旋流分离器(1-5)连接的沸腾床分离器(1-7)，用于处理经微旋流除油后的水洗水，以去除水中的乳化油、分散油和催化剂细粉。
  8. 如权利要求7所述的装置，其特征在于，该装置还包括：
    与微旋流分离器(1-5)连接的沉降罐(1-6)，用于对微旋流分离器(1-5)排出的水洗水进行沉降，实现油水分离；
    与沸腾床分离器(1-7)连接的缓冲罐(1-8)，用于存储经沸腾床分离器(1-7)净化后的水洗水；
    与缓冲罐(1-8)连接的气提塔(1-10)，用于将经沸腾床分离器(1-7)处理的水洗水进行汽提处理；以及
    与缓冲罐(1-8)连接的烯烃分离装置丙烯精馏塔底重沸器(1-9)，用于将经沸腾床分离器处理的水洗水作为热源，进行水洗水的部分余热回收，和/或
    与沸腾床分离器(1-7)连接的压滤单元(1-11)，用于将沸腾床分离器(1-7)中下层含水废料进行压滤脱水，以作回收处理。
  9. 如权利要求7或8所述的装置，其特征在于，所述沸腾床分离器(1-7)为三相分离器和颗粒床层的组合，颗粒床层中使用的媒介为颗粒滤料的多尺寸多形状串联组合。
  10. 如权利要求9所述的装置，其特征在于，所述媒介中选用的颗粒，其粒径梯度变化50％或更大后，同流量下颗粒自转强度增大，自转转速达1500转/秒或更高，颗粒床层再生效率提高。
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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2022056775A1 (zh) * 2020-09-17 2022-03-24 华东理工大学 甲醇制烯烃水洗水深度净化装置及方法
CA3255523A1 (en) * 2022-03-31 2023-10-05 Arxada Switzerland AG MANAGEMENT OF THE WATER CONTENT AND QUALITY OF OIL-BASED WOOD PRESERVATIVES
CN118359264A (zh) * 2024-01-03 2024-07-19 中国石油集团工程股份有限公司 油水分离装置、系统及工艺
CN118236787A (zh) * 2024-03-04 2024-06-25 中国神华煤制油化工有限公司 一种甲醇制烯烃装置催化剂水洗分离方法及系统
CN120518174B (zh) * 2025-07-25 2025-09-23 华东理工大学 一种纳微粉料调控的重油废水分离工艺及装置

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005100511A1 (en) * 2004-03-29 2005-10-27 Exxonmobil Chemical Patents Inc. Heat recovery technique for catalyst regenerator flue gas
CN101352621A (zh) 2008-09-10 2009-01-28 华东理工大学 Mto急冷水和水洗水微旋流脱固方法与装置
CN101352620A (zh) * 2008-09-09 2009-01-28 上海华畅环保设备发展有限公司 Mto急冷水、水洗水中细微催化剂微旋流浓缩方法与装置
CN102093153A (zh) 2010-11-05 2011-06-15 华东理工大学 Mto含催化剂微粉反应气优化组合净化分离的方法与装置
CN103951098A (zh) 2014-04-25 2014-07-30 江苏久吾高科技股份有限公司 甲醇制烯烃工艺中急冷水和水洗水脱固除油的方法及装置
CN104649446A (zh) 2013-11-15 2015-05-27 江苏克莱斯克能源装备有限公司 Mto急冷水和水洗水液固分离方法与装置
CN107382654A (zh) * 2017-09-01 2017-11-24 上海华畅环保设备发展有限公司 甲醇制烯烃急冷水沸腾床分离方法及装置
CN107433055A (zh) * 2017-08-30 2017-12-05 上海华畅环保设备发展有限公司 沸腾床分离器中沸腾颗粒再生方法及装置
CN107512787A (zh) * 2017-09-01 2017-12-26 上海华畅环保设备发展有限公司 沸腾床分离器中分离媒质排序方法
CN108328761A (zh) * 2017-08-29 2018-07-27 华东理工大学 Mto水洗水工艺连续运行周期延长的方法及装置
CN110980981A (zh) * 2019-11-05 2020-04-10 陕西延长石油延安能源化工有限责任公司 一种甲醇制烯烃水洗水深度净化装置及其净化方法

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101544529B (zh) * 2008-03-25 2013-02-27 中石化洛阳工程有限公司 含氧化合物制烯烃工艺反应生成气预处理方法及设备
CN206624799U (zh) * 2017-03-15 2017-11-10 神华集团有限责任公司 有机含氧化合物制烯烃装置
CN206769022U (zh) * 2017-04-26 2017-12-19 神华集团有限责任公司 污水池装置
CN111282372A (zh) * 2020-01-16 2020-06-16 董国亮 一种洗涤塔工艺水的热量回收方法

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005100511A1 (en) * 2004-03-29 2005-10-27 Exxonmobil Chemical Patents Inc. Heat recovery technique for catalyst regenerator flue gas
CN101352620A (zh) * 2008-09-09 2009-01-28 上海华畅环保设备发展有限公司 Mto急冷水、水洗水中细微催化剂微旋流浓缩方法与装置
CN101352621A (zh) 2008-09-10 2009-01-28 华东理工大学 Mto急冷水和水洗水微旋流脱固方法与装置
CN102093153A (zh) 2010-11-05 2011-06-15 华东理工大学 Mto含催化剂微粉反应气优化组合净化分离的方法与装置
CN104649446A (zh) 2013-11-15 2015-05-27 江苏克莱斯克能源装备有限公司 Mto急冷水和水洗水液固分离方法与装置
CN103951098A (zh) 2014-04-25 2014-07-30 江苏久吾高科技股份有限公司 甲醇制烯烃工艺中急冷水和水洗水脱固除油的方法及装置
CN108328761A (zh) * 2017-08-29 2018-07-27 华东理工大学 Mto水洗水工艺连续运行周期延长的方法及装置
CN107433055A (zh) * 2017-08-30 2017-12-05 上海华畅环保设备发展有限公司 沸腾床分离器中沸腾颗粒再生方法及装置
CN107382654A (zh) * 2017-09-01 2017-11-24 上海华畅环保设备发展有限公司 甲醇制烯烃急冷水沸腾床分离方法及装置
CN107512787A (zh) * 2017-09-01 2017-12-26 上海华畅环保设备发展有限公司 沸腾床分离器中分离媒质排序方法
CN110980981A (zh) * 2019-11-05 2020-04-10 陕西延长石油延安能源化工有限责任公司 一种甲醇制烯烃水洗水深度净化装置及其净化方法

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
See also references of EP4215497A4
WEN-JIE LV ET AL.: "UU-type parallel mini-hydrocyclone group separation of fine particles from methanol-to-olefin industrial wastewater", CHEMICAL ENGINEERING & PROCESSING: PROCESS INTENSIFICATION, vol. 131, 16 March 2018 (2018-03-16), pages 34 - 42, XP085454180, ISSN: 0255-2701, DOI: 10.1016/j.cep.2018.03.015 *

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