Packing tower, packing equipment series

The separation performance of a structured packed tower depends on the inner parts, i.e. packing, distributor, collector, etc. At the same time, it also depends on many parameters, such as gas load, liquid load, material properties, operating pressure, packing wetting performance and uneven liquid distribution, etc. Up to now, it is not possible to accurately calculate the separation performance of the tower from the geometry of the packing. It is necessary to measure accurate data through the theory of the packing tower and through the test tower under different conditions. The user can determine the size of the tower and the required packing height according to the first-class approximation. If an economical and reasonable structural form is required, our factory is willing to cooperate closely with the user.

1. The separation efficiency of the regular packing is high, and the extraction rate of the rectifying column is high. The oxygen and nitrogen extraction rates of the air separation plant are two kinds: the extraction rate of the complete set of devices and the extraction rate of the rectifying column. Since the extraction rate of the complete set of devices is related to the capacity of the air separation plant. The output of liquid products is related to other factors, it is difficult to measure the characteristics of the high separation efficiency of the regular packing. The extraction rate of the rectifying column, especially the extraction rate of argon, can better represent the design level of the air separation plant. After actual measurement, a new type of air separation plant has been put into operation. The oxygen extraction rate of the rectifying column has reached more than 99%; the extraction rate of argon has reached 79%.

The high separation efficiency of the structured packing upper column and the crude argon column is due to the significant reduction in their operating pressure. The lower the operating pressure, the more favorable the separation of oxygen, nitrogen and argon, especially the separation of oxygen and argon. Generally, the extraction rate of oxygen can be increased by 1% to 3%; the extraction rate of argon can be increased by 5% to 10%.

The extraction rate of the distillation column also depends to a large extent on the amount of expansion air entering the upper column, especially the extraction rate of argon. Therefore, continuously improving the isentropic efficiency of the turbo expander and the booster ratio of the booster is the key to improving the extraction rate of the distillation column.

2. The void of the regular packing is large, the capacity is large, and the diameter of the tower is reduced to facilitate the transportation of the regular packing. The porosity of the regular packing can reach more than 95%. In the sieve plate tower, the area of the orifice plate accounts for about 80% of the cross section of the tower, and the opening rate is about 8 to 12%, which is far less than the airfall rate of the packing layer. For the same load, the diameter of the packed tower is smaller than that of the sieve plate tower; in general, its cross-sectional area is only~ 70% of that of the sieve plate tower, which is conducive to transportation for large air separation equipment.

3. Structured packing has a small liquid holdup, a large operating liquid-gas ratio and flexibility, and can quickly adapt to changing operating conditions. The operating load of a sieve tray tower is limited by the liquid leakage from the sieve holes and the flooding velocity, while the packed tower is only limited by the flooding velocity. Therefore, their operating loads can vary within a wide range. The design load range of a packed tower can reach 40% to 120%. The oxygen production of the upper tower with structured packing in the 12000 m³/h air separation equipment of Shanghai No. 5 Steel Plant can be adjusted within the range of 9000 to 14000 m³/h, and the operating load range is only 75% to 117%.

Since the liquid holdup of a packed tower is small, generally only 1% to 6% of the tower volume, while the liquid holdup of a sieve tray tower is 8% to N% of the tower volume. A small liquid holdup means that the liquid stays in the tower for a short time, the operating pressure drop is small, and it is also beneficial for operating under changing conditions. However, this needs to be verified in the actual operation under changing conditions in the future.

4. The startup time of the device is significantly shortened. The startup process of the air separation equipment operates without product output. Therefore, shortening the startup time is one of the ways to save energy and reduce consumption in the air separation equipment. The startup time of the air separation equipment refers to the time required from starting the expander to oxygen production. After the upper tower adopts structured packing, the liquid volume held during normal distillation is significantly reduced, which greatly shortens the startup time of the air separation equipment.

Geometric characteristic parameters of SW type mesh corrugated packing

Geometric characteristic parameters of wire mesh corrugated packing: SC = CY, SB = BX

Geometric characteristic parameters of perforated plate corrugated packing

Geometric characteristic parameters of calendered perforated plate corrugated packing