172-Technical proposal for the swirl trap at the top of the MDEA absorption tower in sulfur recovery units and optimization: Discussion on the use of vane separators

This post was last edited by luoli519 on 2024-4-7 at 11:24. In companies in industries such as petrochemicals, natural gas, coal chemicals, fertilizers, and environmental protection, MDEA purification and sulfur recovery systems are often installed specifically for these purposes. Some companies also use low-temperature methanol washing or tannin methods. And the absorption tower is one of the key core devices. The selection of gas-liquid separation technology at the top of the absorption tower determines the consumption of absorbents such as MDEA or methanol in the tower, as well as its operational efficiency; it even affects the effectiveness of air purification. The gas-liquid separation equipment at the top of absorption towers is often referred to in the industry as a demister, separator, or foam trap; the term “absorption trap” was introduced in the past two years by Sinopec as an alternative name for the cyclone separators used at the top of MDEA absorption towers. Although this term can lead to confusion with the term used for harmful insects, chemical engineering professionals generally understand what it refers to. Once, a client had doubts regarding the quotation request from the design firm concerning the \"scrubber\" at the top of the MDEA absorption tower; they asked us to provide our technical solution to clarify these doubts, based on the design firm’s quotation request for the same component. This technical article analyzes and discusses this actual case.

The attached diagram shows excerpts from the quotation request we submitted to the owner regarding the swirl \"absorber\" at the top of the MDEA absorber in their 10,000 tons per year sulfur recovery unit, so that everyone can understand the origin and meaning of this \"absorber\". As can be seen from the accompanying drawings, the equipment quoted together with the swirl \"scrubber\" at the top of this MDEA absorption tower includes a liquid separation tank, among others.

As can be seen from this request for quotation, the gas stream processed by this sulfur recovery unit consists of three types of streams: sulfur-containing dry gas, sulfur-containing light gas, and sulfur exhaust gas. From the perspective of the MDEA absorption tower as a process unit, a liquid separation tank is installed at the front end of the gas inlet pipeline, while an amine liquid recovery unit is located at the back end of the gas outlet. This is confirmed by the names of equipment such as dry gas liquid separation tank, dry gas amine liquid recovery unit, low-pressure gas liquid separation tank, and low-pressure gas amine liquid recovery unit mentioned in the quotation document. There should be other related equipment as well; it’s just that the design institute has included them in other quotation packages.

This post was last edited by luoli519 on 2021-1-12 at 12:42. The figure below shows the basic process data for the swirl capture device at the top of the exhaust gas absorption tower, as provided by the design institute in the request for quotes. As can be seen from this document, the design institute only provided the gas-phase condition data at the top of the MDEA absorber, but lacked the gas-phase viscosity data and the physical-chemical data related to liquid droplets and foam. Clearly, only professional dynamic separation technology companies are capable of designing technical solutions, provided that they first utilize their precise dynamic separation techniques to calculate and design the system platform, and then retrieve and supplement such data from databases. Otherwise, non-professional companies can only rely on experience, rough estimates, or even hunches to develop technical solutions.

This post was last edited by luoli519 on 2024-4-7 at 11:25. The missing physical and chemical data related to substances obviously pose no difficulty for professional dynamic separation technology companies. The image below shows the cyclone separator tower designed by a specialized dynamics separation technology company in operation at a project site. This type of cyclone separator is designed through a precise dynamic gas-liquid separation calculation and design platform, and it is used to efficiently and quantitatively separate and remove droplets, foam, and solid particles from high-volume air streams. Its main typical application areas are as follows: 1. Gas-liquid separation in the hydrogen desulfurization unit of catalytic hydrogenation and reforming units in the petroleum refining industry. Examples include the dry gas cyclone hydrocarbon removal device in the hydrogen desulfurization unit for heavy oil catalytic hydrogenation units, the dry gas cyclone liquid separation tank in the same unit, the dry gas cyclone hydrocarbon removal device (cold high-pressure separator) in the desulfurization unit of diesel hydrogenation units, the dry gas cyclone liquid separation tank in that unit, the low-pressure gas cyclone hydrocarbon removal device in the desulfurization unit of diesel hydrogenation units, and the low-pressure gas cyclone liquid separation tank (cyclone amine removal device) in the same unit. 2. Gas-liquid separation in the inlet and outlet pipelines of high-pressure and ultra-high-pressure multi-stage compressors, such as the high-pressure ammonia cyclone gas-liquid separator in the outlet pipeline of the ammonia synthesis tower in ammonia synthesis plants, the gas-liquid cyclone separators at the inlet, between stages, and in the discharge section of the multi-stage compressors for CO2 in urea production plants, and the gas cyclone separator at the compressor inlet in high-pressure natural gas transmission boosting stations. 3. Steam demisting and separation using high-pressure and ultra-high-pressure steam drums, such as steam swirl separators at the inlet of steam turbines, steam swirl separators in steam injection boilers used in oil fields, and steam swirl separators in redox reactors. 4. Natural gas extraction, processing at stations, and pipeline transmission systems are used to separate and remove condensate oil, condensate water, and solid particles from high-pressure, high-density natural gas; examples include cyclone gas-liquid separators at wellheads and pre-cyclone separators before metering skids for high-pressure pipeline-transmitted natural gas.

This post was last edited by luoli519 on 2023-3-23 at 12:42. The attachment is the \"Data and Chart Summary\" for the swirl trap at the top of the MDEA absorption tower, which was prepared using a specialized dynamics separation technology and a configuration design system platform, based on the operational data of such traps as recorded in the aforementioned inquiry document. As can be seen from the \"Numerical Diagrams and Tables,\" a swirl trap consists not only of the trap itself but also of a corresponding anti-siphon liquid dropping system; both components need to work together effectively.

This post was last edited by luoli519 on 2021-1-12 at 15:47. The cyclone separator relies on its internal cyclone components, and the most crucial element of these components is the system platform for accurate calculation of dynamic separation techniques and for configuration design. It is also the various internal structures of these cyclone components, along with the specified dynamic conditions for their effective operation, that determine their performance. To claim that any technology or device is “universal” is surely a lie or a joke; every technology and device has certain prerequisite conditions for its efficient operation. Specifically, swirl separation internals with different internal structures include axial-flow and reflective types. The computational and configuration design system platform for precise dynamics separation technology must be based on a cyclonic flow pattern; other horizontal or vertical flow patterns cannot be used as a makeshift solution, as this would result in actual separation efficiency that is far from what the technical plan assumes. Because separators with different flow patterns have distinct separation mechanisms.

This post was last edited by luoli519 on 2021-1-12 at 15:48. A cyclone separator is a type of dynamic separator that utilizes the vector field generated by the rotation of fluid within the flow channel (pure radial rotation creates a centrifugal field, pure axial rotation creates a hypergravity field, while diagonal rotation results in a vector field that is a combination of the two). A technical solution for such a separator must be developed through precise dynamic separation calculations and a well-designed system platform. To achieve high separation efficiency, the kinetic energy and momentum possessed by the fluid must meet a relatively high minimum threshold; otherwise, the separation efficiency will be only on par with that of conventional cyclone separators. And fluids with high values of kinetic energy and momentum rotation inevitably result in a high pressure drop. Therefore, the separation efficiency of the cyclone separator is directly proportional to the operating pressure drop. Requiring a cyclone separator to achieve high separation efficiency at low operating pressure drops goes against the principles of kinetic separation and is simply unattainable. Therefore, high-efficiency cyclone separators used abroad are employed in applications with high operating pressures, high kinetic momentum, and where high operating pressure drops are acceptable. The so-called claim in China that \"high separation efficiency can be achieved at low operating pressure drops\" goes against the principles of kinetic separation and is a fallacy. For the aforementioned operating conditions, we have utilized precise dynamics separation technology to calculate and design a set of 2\" cyclone separation internals that represents the most advanced solution available internationally; its separation accuracy is such that the operating pressure drop at 5.08 microns exceeds 1000 Pa.

This post was last edited by luoli519 on 2021-1-12 at 15:49. The request for quotes regarding the swirl capture device at the top of the MDEA absorption tower specifies that the bidder for the swirl separator must provide patent documentation. In fact, as a device, the cyclone separator’s patented technology relates to its configuration structure ； However, for dynamic separators under different operating conditions, a patent for a single type of swirl separator configuration cannot effectively meet the requirements regarding dynamic separation efficiency in various conditions; only a precise technical calculation and configuration design system platform for dynamic separation can dynamically address the efficiency requirements under different operating conditions. Everyone can check whether there are any patents for system platforms related to the calculation and configuration design of precise dynamic separation technologies in publicly available patents at home and abroad No company is willing to make its precision dynamics separation technology calculation and configuration design system platform available to the whole world. Therefore, as required in the tender document shown in the figure, for a cyclone separator, the bidder is asked to provide patent technical documents; from a technical perspective, these can only serve as supporting materials.

This post was last edited by luoli519 on 2021-1-12 at 14:14. The attached image shows an excerpt from the patent for our company’s reflective-flow multi-factor cyclone separator; it was provided in response to a request from a design institute. However, as a patent technology related to micro-cyclone separation configurations, it serves merely as evidence of the company’s expertise in dynamic separation technologies.