Three-layer efficient high-speed gas-liquid mass transfer tower board

Abstract

The invention relates to a three-layer high-efficiency and high-speed gas-liquid mass transfer tray, comprising a tray 1, a plate hole 2, a gas riser 3, and a downcomer 4. The tray 1 is provided with a plate hole 2, the tray 1 and the gas riser 3 are connected, the tray 1 is connected with the downcomer 4, the tray 1 is divided into three layers, and the tray 1 is composed of more than one mass transfer element composed of plate holes 2 and lifters 3 in parallel, and the bottom of the tray 1 is Gas-liquid dispersion plate, there is a gap between the bottom tray and the mass transfer element; the middle tray is a liquid collection plate, which is connected to the top of the lifter 4, and the liquid collection plate is connected to the downcomer; the top tray is a mist baffle , the gas-liquid phase fully contacts the mass transfer in the element, but only the gas phase and the liquid on each layer of the tray flow in a single phase, and the liquid does not mix at all before and after the mass transfer. After the gas-liquid mass transfer, the liquid phase is separated from the gas phase through the mass transfer element and the mist collection plate. The configuration is simple in structure, can eliminate amplification effect, increase processing capacity, and enhance mass transfer.

Description

technical field [0001] The invention relates to a mass transfer tray mainly used in tray towers in petroleum and chemical processing industries, specifically a three-layer high-efficiency and high-speed gas-liquid mass transfer tray. Background technique [0002] Tray tower is the most common gas and liquid mass transfer equipment. The tray types are generally bubble-cap trays, valve trays and sieve trays. With the development of tower technology, separation equipment The requirements are getting higher and higher, and many new trays and internals have been developed to meet the growing needs. [0003] The improvement of the internal parts of the tray tower basically revolves around the improvement of the gas-liquid contact configuration on the tray, the way of blowing, the rational use of the tray space, and the reduction of mechanical resistance, so as to reduce the mist entrainment, leakage, etc., and improve the efficiency of the tray. or reduce back-mixing, improve tra...

AI Technical Summary

Problems solved by technology

The development of the existing spray-lifting trays is mainly reflected in the improvement of the cover of the spray element. The reasons for the decrease in the efficiency of the plate when the large throughput is caused have not been analyzed. Although the improvement of the top cover structure can improve the mass transfer of the gas-liquid two-phase Separation, reduce mist entrainment, but in fact, through experimental research, it is found that the reason for the decrease in tray efficiency is due to the decrease in the relative lift of liquid during high gas velocity operation, while the existing jet trays are basically Liquid is sucked from the tray through the bottom gap of the mass transfer element, and sufficient negative pressure must be formed to ensure the lift of the liquid, which requires a sufficiently high gas velocity at the expense of the pressure drop of the tray, and a high gas velocity After a certain level, it has little effect on the amount of lift

[0010] (2) The mixing of the mass-transferred liquid and the non-mass-transferred (not lifted) liquid is another main reason for the low efficiency of the plate

Moreover, there is a problem of liquid circulation in the initial stage of the liquid in the riser jet, which will also restrict the improvement of the liquid lift.

Although some proprietary technologies add another layer of trays above the mass transfer trays to collect the liquid after mass transfer, which can solve the problem of liquid back-mixing, but it will greatly increase the pressure drop of the trays and complicate the structure, resulting in unnecessary energy loss

[0011] (3) Another common disadvantage of the existing spray trays is that the pressure drop of the tray is large, because the inherent feature of this type of tray is to use the high gas velocity to form a negative pressure at the inlet of the mass transfer element to attract the liquid to rise, and in the A cover or filler should be added to the top of the mass transfer element. The limitation of this infusion method will increase the resistance coefficient of the fluid passing through the tray, reduce the upper limit of the operating capacity, and also restrict the scope of use of this type of tray.

[0012] (4) Adding a cover on the top can accelerate phase dispersion, enhance mass transfer, and improve mass transfer efficiency to a certain extent, but it also increases the difficulty of phase separation, and the spraying between two components will accelerate mist entrainment , to reduce the operating upper limit of the tower equipment

[0013] (5) The existing tray structure is complicated, the cost is high, and maintenance is difficult, so it cannot be applied to coking-prone systems and decompression operations

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