Design And Development Of Devices Of Physical Supperpress Venting Of Vessel

Super-press venting of vessel is an important safety issue in modern chemical plant. An explosion and great loss will be caused if the supperpress of the vessel will not be solved in good time. As a result, it is very important for the property of the nation and the safety of the people to research how to vent the supperpress vessel in time.In this paper, venting of pressure have been investigated. And a program for venting of pressure design which is used widely and easily and exactly is programmed.The major work of this paper is following:1, This paper summarizes the research status of this area. The emphasis is laid on the design strategies, design models and some comments are made on these respects. Based on the energy and mass balance, Two hydrodynamics ingredients which affect the venting coefficient C_d have been derivative, and the simple calculate formula is gained.The methods and applicable scope of relieving area by two phase flow model were discussed in this paper. And the characteristic of two phase flow model of API520 was compared with that of DIERS in this paper as well.2, Based on the analysis of the codes of API520, ISO6718 and GB567 for venting of pressure, the program has been designed one phase flow according to API520,two phase flow according to DIERS.The program which is written with Visual Basic 6.0 is used easily and the interface of the program is very friendly and visual. The program found the database of critical parameter, the database of liquid and gas by Access2000 in the program, not only the user of the program is free of data input, but also avoid the trouble of inquiring about the designing chart by hand. The database is linked with the program by DAO ( Data Access Object ), and update by users is allowed.3, The program can calculate the relief quantity, relief area and relief caliber of venting of pressure. The users can do the following venting designs: The supperpress venting of the vessel which is full of steam; The supperpress venting of the vessel which is full of gas compressor; The supperpress venting of the vessel which is full of liquefied gas; The supperpress venting of the vessel which is full of liquid; The supperpress venting of thevessel which is full of liquid and vapor.4, Conceptual design of pressure relief systems is an important stage in the design of a safe process plant. The conceptual design stage consists of the following steps: firstly, after deciding on the location of pressure relief devices, the program can ascertain the type of pressure relief device automatically for each identified location if it is needed, i.e. safety valve and/or bursting disc (rupture disc), and select the venting device type on the base of the conditions automatically. Five safety valves and eight bursting discs are offered in this program, It will offer the calculating result and the showing chart 。5, The program for venting design has been checked up by factual examples and the error of the design in under 6%. It can provide a designing basis for the designer.