| At the department of the refining oil, petroleum chemical industry, industry of fine chemicals, foodstuff, medicine and environmental protection etc., equipment of gas-liquid is very important unit equipment used widely. It is used in the operations of rectifying, absorbing, humidification, de-humidification etc.. As usual, its investment is about 20 percent of all investment, and even gets 50 percent high.Distillation or rectification is a kind of separating operation. At the chemical industry processing, it plays a decisive role. So it is a very important thesis for study which scholars internal and external pay close attention to. At the before 1970' s, plate column plays absolute predominance in column plant. When energy crisis occurred, the question on saving energy is high lightly emphasized. The technology of packing column made great process, and charged into the situation that plate column is main equipment in the distillation equipment. Coming into 1990' s, the developing speed of packing is rather slow, and goes into a comparatively period. On the contrary, the technology of plant column has obvious progress. In the study field of tray deck, in our country, there is less active than other countries. But three-dimensional tray is known that it owns plate shape and provides packing column' s separating efficiency. Depending on his good performance, it attracts many studies to do many things in this respect.Based on relate to literature reported, the thesis designs the three-dimensional tray that includes three kinds of structure called Tray 1, Tray2, TrayS. There is a research on its hydrodynamic performance. Its particular content mainly includes transforming old equipment, designing new types of three-dimensional tray, and measuring its hydrodynamic performance that includes measuring dry plate pressure, operating pressure, entrainment, leak source, down opening' s liquid blowout and seeing out their affecting factors.Experiment' s conclusion and analysis shows that when tray' s openingrate is same, at the respect of pressure,the designing three-dimensional tray is higher than conventional sieve tray, and is equal or even a littlelower than floating valve tray. It demands that the study' s viewpoint home is reasonable, and there is different from Japanese patent demanded. But to increase sieve tray' s opening rate, there are many factors limited. At the experiment' s situation, that is to say, when the opening rate is 12.8 percent, to increase sieve tray' s opening rate, it is hardly possible. On the contrary, due to three-dimensional tray' s opening designing specially, its opening rate may still improve much. Three-dimensional tray' s dry plate pressure basically is 2 power of tray opening velocity. Transforming flat plate opening to spraying opening is a very effective way to reduce plate pressure, and can reduce about 25 percent. From investigating on determinative factors of dry plate pressure, we know that plate orifice pressure is mainly determinative factor. At the operating process, three-dimensional tray' s entrainment is very little. For example, the entrainment of Tray 2 and Tray 3 both do not get serious degree. At the same situation, three-dimensional tray' s entrainment is much less than that of sieve plate. For example, Tray 2 does not get only 40 percent of sieve tray' s. The velocity of leak source is almost equal to that of the sieve tray at the same situation. Three-dimensional tray' s operating upper limit is not decided by serious entrainment, but by down opening liquid blowout. And its operating lower limit is at the same as the sieve' s, this to say , it is decided by leak source. At the L=15001/h operating point, three-dimensional tray' s turndown ratio is larger than that of sieve tray, and is about 45. 2 percent higher. At the all operating process, fluid-flow has rather little effect on the hydrodynamic performance of three-dimensional tray, and higher liquid thickness at the plate is very good to three-dimensional tray' s hydrodynamic performance. So i... |
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