Posted 22 April 2011 - 01:23 AM
first of all i wud like to discuss about dalton's law of partial pressure,
sir,, i'v fair idea of it's application & implications ,, and according to my knowledge, the terms in dalton's eqn. are the individual pressures of gases present in the vessel
(not liquid's vapor pressure, if we assume zero vaporization for time being; as the primary purpose of nitrogen blanketing is to avoid vaporization)....
please explain if i am wrng,
now coming back to my problem,,, i wud like to elaborate it further,,
actually we r having storage vessels for "hydrocarbons",of which the normal boiling point ranges within (0 - 10) o C,, and our ambient temperature ranges from (25 - 32) oC, we want to keep that fluid in liquid state,, and in order to keep them liquid we must increase the vessel's pressure to counter their vapor pressure. as boiling temperature will increase then and stops the liquid from vaporizing
(by applying N2 gas, in our case),, one more purpose behind applying (nitrogen) pressure is to use this pressure as pumping agent, as otherwise our fluid can't stay liquid.......,.
and here comes the problem that api standards(2000) only tell about blanketing at near atmospheric conditions....., whatif some one wants to blanket at high pressures,
please assist me if u can,, thanx 4 ur correspondence.
Engineer Sohail Malik