88- The feather leaf separator is used in the design of the start-up buffer tank and inlet separation tank of the MRC process package with a daily production of one million standard cubic meters of LNG.
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This post was last edited by luoli519 on 2023-9-27 15:02 In recent years, domestic LNG units planned to be built and already put into operation have adopted feather leaf separators as the core unit of the gas-liquid separation tank in the inlet section of the MRC compressor system. They are mainly concentrated in large-scale LNG units with a daily output of one million cubic meters using foreign process packages or well-known domestic process packages. Foreign LNG process package providers pay special attention to the configuration of gas-liquid separation equipment at the inlet of the core unit MRC compression system, such as the GE joint venture Encoro LNG process package, Linde LNG liquefaction process package, etc. Please discuss based on your own LNG project-related equipment conditions.
The MRC Startup Suction Drum (MRC Startup Suction Drum) is mainly used for start-up of new projects and re-starting after equipment overhaul, especially when the system temperature is high and the system temperature has not been reduced to the MR steady-state system temperature condition, and the MR gasification volume is large and the liquid is serious. When abnormal working conditions occur in the LNG liquefaction unit, it can also be used as a temporary emergency MR storage device. Some domestic process packages do not pay enough attention to the special role of the MRC compression system start-up buffer tank as foreign LNG process packages, and even do not have an MRC compression system start-up buffer tank at all.
Generally speaking, as a mixed refrigerant storage separation tank, the storage capacity of liquid mixed refrigerant is required to be large, and because the mixed refrigerant has a large amount of vaporization and a large amount of gas-liquid mixing and entrainment, it is better to adopt a horizontal arrangement. For example, MRC start-up buffer tank and MRC compression unit primary inlet separation tank. Of course, some process packages design the MRC start-up buffer tank, MRC compression unit primary inlet separation tank, and MRC compression unit secondary inlet separation tank into vertical structures. Relatively speaking, the liquid storage capacity of a horizontal structure separator of the same size will be greater than that of a vertical structure, but the requirements for internal dynamic separation design and configuration technology are higher.
The main function of installing a high-efficiency gas-liquid separator in the mixed refrigerant compression system is to: 1. At the inlet of each stage of compression unit, the liquid refrigerant is removed from the inlet air flow to prevent the liquid phase from entering the compressor, causing compression difficulties, increased power consumption, excessive temperature rise, and even "liquid shock" to the compressor and damaging core equipment. ； 2. At the outlet of the compression unit at each stage, the liquid refrigerant is separated from the air flow in a timely manner. The refrigerant is only used for cooling the gas phase, avoiding the consumption of refrigerant for liquid cooling, and the energy saving effect is obvious. ； 3. The compressor interstage separator has the functions of both inlet separator and outlet separator. ； 4. In addition, the separator also has anti-surge, noise reduction and buffering functions.
This post was last edited by luoli519 on 2023-9-27 15:03 In the mixed refrigerant compression unit of the LNG device, the precisely designed feather leaf gas-liquid high-efficiency defoaming and mist separator has made a significant contribution to reducing MRC compressor system design redundancy and saving investment, reducing refrigerant cooling capacity consumption, reducing compression power consumption, etc.； As for the technological upgrading of old equipment, the production capacity of the original compression equipment can be greatly improved. Therefore, whether it is a new project owner, an old device owner, or an LNG project EPC unit, they are very concerned about the installation of this type of feather leaf separator.
The buffer separation tank of the refrigerant compression unit of a traditional LNG device is often an empty tank without dynamic separation technology internal parts, which mainly serves as an inlet buffer. However, the separation effect of droplets and foams settled by gravity is poor, especially under conditions with large gas volumes, resulting in a large amount of droplets and foams carried by the airflow entering the compressor. When selecting a compressor, the design unit has to enlarge the model in a large proportion based on safety and reliability factors, resulting in a large investment in the compressor. Due to the large amount of liquid in the air intake, compressor power consumption and frequent operating failures result in high project costs.
This post was last edited by luoli519 on 2023-9-27 15:03. Here are the details of the Encoro LNG process package used in a northwest LNG project, which requires the use of feather-leaf separation internals for the MRC start-up buffer tank.: 1. Medium: N2, CH4, C2H4, etc.; 2. OP: 371kPaA; 3. OT: 34.89℃ ； 4. Gas phase flow: 37638.52Am^3/h, MW=35.17, viscosity 0.011cp.
This post was last edited by luoli519 on 2023-9-27 15:03 The technical requirements of the Encore LNG process package for the MRC start-up buffer tank are:: 1. Separation efficiency: 4N grade 2 micron ； 2. Operation flexibility: 60%~110% ； 3. Separator type: Vertical ； 4. Separate internal parts type: G50 type feather leaf separation internal parts set+PAD ； 5. Materials: SS304。
This post was last edited by luoli519 on 2019-12-23 16:13 The picture below is a simplified diagram of the MRC start-up buffer tank of the Encore process package with a daily output of one million standard cubic meters of LNG project.：
This post was last edited by luoli519 on 2023-9-27 15:03 The process conditions of the interstage feather separator of the mixed refrigerant cycle compressor required in the Linde cryogenic process package: 1. Operating pressure: 309.79psi ； 2. Operating pressure: 100.058F ； 3. Gas phase flow: 592325.91Lb/h; 4. Gas phase average molecular weight: 30.87 ； 5. Gas phase density: 1.918Lb/ft^3; 6. Gas phase viscosity: 0.011cp ； 7. Liquid phase flow: 922.885gpm ； 8. Liquid phase density: 32.53Lb/ft^3; 9. Liquid phase viscosity: 0.121cp ； 10. Liquid phase surface tension: 66.24dyne/cm。
This post was last edited by luoli519 on 2023-9-27 15:04. The mixed refrigerant cycle compressor inter-stage feather separator designed and completed by Novel's proprietary precision dynamics calculation design system platform has the following performance: 1. Separation efficiency: 100% removal of liquid droplets with a size of 6.03 microns and above, and the residual amount of liquid droplets in the air flow is less than 0.1G/MMSCF. 2. Overall operating pressure drop under rated operating conditions: 0.19psi。