123-Design of a multi-factor cyclone mother-son separator dedicated to the separation of polymer particles from vent steam in Nylon-66 polymerization reactors
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This post was last edited by luoli519 on 2020-1-4 at 13:43. In Nylon-6,6 polymerization plants, it is often necessary to remove the small molecules or solvents generated as a result of the reaction from the reactor in a timely manner, in order to meet the requirements regarding the degree of polymerization and the purity of the product. This post takes as an example the design of a multi-factor cyclone separator specifically used for capturing and separating nylon polymer particles from the superheated steam released from the reaction vessels in a certain nylon-6,6 industrial plant, and discusses it with everyone. I also hope that everyone can share their technical expertise and practical experience in using specialized separators for the capture and separation of polymer particles, droplets, and foam from the off-gases generated by their own nylon-6,6 production facilities or other polymerization reactors.
For this customer in South China, the polymerization reaction of nylon-6,6 takes place in a polymerization reactor at a temperature of 250°C, with a reaction pressure of 2.6 MPaG. The small molecule of water produced in the reaction has clearly formed superheated steam. The small molecule water and its vapor generated by the reaction system need to be released from the reactor in a timely manner to ensure the continued progress of the polymerization reaction.
The owner’s technical staff explained that the release of water vapor needs to be carried out intermittently, with dozens or even hundreds of seconds of release per hour as required. The superheated steam released from the reactor first enters a buffer tank, where large-sized polymers are separated by pure gravity settling. The steam emerging from the top of the buffer tank enters a dedicated multi-factor cyclone separator for mother-son separation, where the polymer powder is removed thoroughly to meet emission standards, after which it is released directly into the atmosphere.
The owner initially turned to a separation equipment company in Guangzhou, which then referred the owner directly to a company specializing in dynamic separation technologies.
The basic process conditions for the multi-factor cyclone mother-son separator provided by the owner, which is used to capture and recover polymer powder before releasing the steam from this device into the atmosphere, are as follows: 1. Steam flow rate: 77914.85 m^3/h; 2. Steam temperature: 100℃； 3. Operating pressure: 1.04 BarA ； 4. Medium: 97% superheated water vapor, 3% nylon-6,6 powder ； 5. Gas density: 0.598 kg/m^3; 6. Gas viscosity: 0.012 cp ； 7. Powder bulk density: 350 kg/m^3.
Owner’s requirements for the separator: 1. The separator must be a multi-factor cyclone mother-son separator, compatible with the existing pipeline of DN350mm； 2. Material: SS316 ； 3. Separation efficiency: not less than 85% ； 4. Operating pressure drop: not exceeding 3.5 kPa ； 5. Removable design ； 6. Provide key technical documents such as the \"Calculation Report for Precise Dynamic Gas-Solid Separation Process\", the \"Separation Efficiency Curve Chart\", and the \"Operating Pressure Drop Curve Chart\" to demonstrate the scientificity, precision, and reliability of the design.
In response to the owner’s requirements regarding separators, a specialized company in dynamic separation technology has utilized its precise dynamic separation technology, along with its calculation and configuration design system platform, to provide the following technical details for a separator designed specifically for separating polymer particles from vent steam: 1. Separator type: G54 multi-factor cyclone mother-son separator； II. Separator size: ID100” x SM/SM 101" ； Material: SS316 ； Removable design ； III. Separation efficiency: 99% separation and removal of polymer particles with a size of 6.27 microns and above ； IV. Operating pressure drop: 3.42 kPa.