with temperature is increased by 10F in every stage. Repeat the procedure from (g) to (n), for stage 2, stage 3, stage 4.

The stream INLET STAGE 2 is as inlet stream to the separator. Calculate the required time of increasing temperature at stage 1, that Is (Q-1) / (21.000 F.A ^0.82) The heat input to V-1 in HYSYS simulation is Q-1 BTU/hr, whereas the actual heat input is Q API = 21.000 F A ^0.82 BTU/hr The stream LOAD STAGE 1 is relieving load fire case Adjust mass flow rate of VAPOR 2 to achieve actual volume flow of INLET STAGE 2 is equal with initial actual volume STREAM OPERATING. Mix CONDENSATE 2, WATER 2 and VAPOR 2 to be INLET STAGE 2. The VAPOR will be divided into two streams, LOAD STAGE 1 and VAPOR 2 The outlet stream is CONDENSATE 2, WATER 2 and VAPOR. Thus, set the temperature outlet separator (V-1) of 10 F higher than the RELIEVING CONDITION. Heat input due to fire case is calculated by increasing temperature with interval 10 F. The stream RELIEVING CONDITION (e) is as inlet stream to the separator. (d) and (e) is model of the separator at relieving condition as initial stage which is PSV will start open Input the pressure of relieving pressure value (=1.21 x set pressure).į. Balance the mixing stream (d) to stream RELIEVING CONDITION. The outlet stream from separator is mixed.Į. (This simulation assumes the PSV instantly reach relieving condition after opening). The temperature and pressure will increase to initial RELIEVING CONDITION due to fire. Adjust Q-100 (heat input to vessel) to achieve pressure RELIEVING CONDITION The STREAM OPERATING is as inlet stream to the separator. (a) and (b) is model of the separator at normal operating condition based on actual condition.ĭ. Mix those streams to be STREAM OPERATINGĬ. Adjust mass flow for those streams, to achieve actual volume for each stream in accordance with inventory volume calculation (1). Input composition, pressure, and temperature as operating condition of the three phase separator.ī. Define stream for WATER, CONDENSATE, and GAS. Determine the inventory volume of isolated system, both for condensate, water, and gas based on actual size of the vessel and pipe.Ī. Let imagine the system consist of a three phase separator below, the fire case calculation procedure is as follow ġ. In this article, I will explain you step by step the rigorous method for fire case During fire, liquid in the vessel will be vaporized, but the amount of vapor formed is not fixed, because the liquid composition is change overtime.

The latent heat of vaporization is rather difficult to be determined. The heat input have been discussed before, see fire case –heat input rate. In previous article, I have explained that relieving load for fire case can be calculated as heat input divided by latent heat of vaporization.

Fire case psv