(29f) Dry Tray Pressure Drop of Double Weight Float Valve Trays

Dry tray pressure drop of double weight float valve trays

Lehuan Wu¹, Jun Wang ¹, Yansheng Liu ¹,  Xuqiang Guo ¹ and Yufeng Hu ¹

¹ State Key Laboratory of Heavy Oil Processing Research, China University of Petroleum, Beijing 102249,China

Abstract: This paper calculates the dry tray pressure drop of double weight float valve trays based on a new dry tray pressure drop model proposed by Wang^[1]. Firstly, pressure drop is related to the positions of valves on the trays, and the opening process of double weight valves can be divided into 7 sections by 6 special points (ignoring the effect of light valve inclined state on the pressure drop). Secondly, gas velocities at every apparent balance point can be calculated as well as the fractions of float valve state in different gas velocity sections. Finally, dry tray pressure drop can be obtained through the physical model. A series of hydraulics experiments have been done on the large-scale experimental tower, and two types of float valve combination (32&58g and 32&80g) and four types of fractional hole area (5%, 8%, 10% and 14%) are studied. Besides the ratio of light valves to heavy valves is 1(R=0.5), and the valves are distributed in a certain way. Comparing the model calculated values with the experiment results, fractional hole area has little influence on the dry tray pressure drop. For the effect of light valve inclined state on the pressure drop is ignored, the deviation caused by this neglect is acceptable, however, the effect of heavy valve inclined state cannot be ignored and it will cause a relatively large positive deviation, which have been proved in the experiments. The model calculated values fit the experiment values very well.

Keywords: double weight valve; dry tray pressure drop; large-scale; balance point