Countercurrent exchange

About: Countercurrent exchange is a research topic. Over the lifetime, 2255 publications have been published within this topic receiving 28687 citations. The topic is also known as: Countercurrent exchange.

On Gas Separation by Permeation with One-Side Mixing

Abstract: A calculation method for gas separation by permeation with one-side mixing is proposed. Five types of stage flow patterns (one-side mixing, countercurrent flow, cross flow, cocurrent flow, and perf...

Single-column cyclic separation system for preparing high-purity tanshinone compounds and method thereof

Abstract: The invention relates to a three-column cyclic separation system for preparing a high-purity tanshinone compound and a method thereof. The three-column cyclic separation system comprises three countercurrent chromatographic columns, three pumps, three detectors, three collectors and four six-way valves, wherein the first countercurrent chromatographic column is used as a start separation column; the second countercurrent chromatographic column and the third countercurrent chromatographic column are cyclic separation columns independent from each other; a sample is subjected to first-dimensional separation through the first countercurrent chromatographic column, sequentially enters the second countercurrent chromatographic column for second-dimensional separation by adjusting the three six-way valves, enters the third countercurrent chromatographic column for third-dimensional separation, and enters the first countercurrent chromatographic column again for the next cyclic separation, so that multi-dimensional cyclic separation on the tanshinone compound is realized; the tanshinone compound comprises dihydrotanshinone I, cryptotanshinone, tanshinone I, 1,2-dihydrotanshinone, tanshinone II A, three-leaf sage root ketone B, methyl tanshinone ester and neotanshinone A. The three-column cyclic separation system is simple in extraction and separation, short in time and high in product purity and can realize continuous operation.

Mass Transfer Enhancement in Double‐Pass, Parallel‐Plate Mass Exchangers under Asymmetric Wall Fluxes

Abstract: A device involving mass exchangers with a permeable membrane inserted to divide the open duct into two subchannels for conducting double-pass laminar countercurrent operations under asymmetric wall mass fluxes, which results in a substantial improvement of the mass transfer, has been developed and investigated theoretically. The resultant partial differential equations for such a double-pass forced-convection mass transfer problem are referred to as conjugated Graetz problems and solved analytically in this work by using an eigenfunction expansion in terms of power series for the homogeneous part and an asymptotic solution for the inhomogeneous part. The theoretical predictions of mass transfer efficiency improvement in double-pass, parallel-plate mass exchangers are obtained by suitably adjusting the permeable membrane location. They are represented graphically and compared with the results from an open duct of a single-pass operation (without a permeable membrane inserted). The increment of power consumption is also discussed.

Method and press tool for fabricating a plate heat exchanger

Abstract: The method involves producing individual plates (1) from a non-pressed plate blank by converting a tool with exchangeable mold elements to a converted tool that produces cross flow plates or countercurrent flow plates. The plate blank is pressed with the converted tool into the cross flow plate or countercurrent flow plate. Corresponding edges (12) and/or contact surfaces (13) and inflow cross-sections (Z1, Z2) and outflow cross-sections (A1, A2) are formed in main flow directions of two respective mediums. Distance between adjacent individual plates is determined. Independent claims are also included for the following: (1) a pressing tool for pressing individual plates for plate heat exchangers (2) a system for manufacturing individual plates for plate heat exchangers.