To ensure normal fluidization of the device, how is the minimum amount of pre-lift steam and main air flow calculated?
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Our facility is a small refinery equipped with a parallel high and low catalytic cracking unit, along with two regenerators. It currently processes 500 tons of residue per day, with a total storage capacity of 18 tons. Could anyone help me calculate the minimum amount of pre-heating steam required, as well as the appropriate pressure and minimum amount of main air flow, in order to ensure proper fluidization of the unit?
I can’t calculate this; it’s probably the job of the design institute~~~:lol All I know is that it’s necessary to ensure normal circulation of the catalysts in both reactors, and the driving force in the regeneration line and the standby line should be equal to the resistance respectively. For example, in a certain coaxial catalytic cracking unit, the driving force in the regeneration line = pressure at the top of the regenerator + pressure difference in the dilute phase within the regenerator + static pressure in the vertical tubes of the regenerator + pressure difference in the transition section of the regenerator + pressure difference in the dense phase within the regenerator = 0.15 + 0.0009 + 0.0072 + 0.0018 + 0.007 = 0.1715 (MPa). The resistance in the regeneration line = pressure at the top of the settler + static pressure in the inclined tubes used for regeneration + pressure drop in the vertical tubes of the regenerator + pressure drop in the lift pipe + pressure drop due to rapid separation + pressure drop caused by the plug valve in the regenerator + pressure drop at the right-angle elbow of the lift pipe = 0.1157 + 0.0163 + 0.0072 + 0.01 + 0.0022 + 0.0123 + 0.0022 = 0.1739 (MPa). Thus, the driving force in the regeneration line is 0.17 MPa, and the resistance is also 0.17 MPa; the two values are roughly equal. In another case, for a catalytic cracking unit with parallel high- and low-pressure sections, the driving force in the standby line = pressure at the top of the settler + static pressure in the dilute phase within the settler + static pressure in the stripping section + static pressure in the inclined tubes used for standby = 0.1437 + 0.0003 + 0.0351 + 0.033 = 0.2121 (MPa). The resistance in the standby line = pressure at the top of the regenerator + static pressure in the dilute phase within the regenerator + static pressure in the transition section of the regenerator + static pressure in the dense phase within the regenerator + pressure drop caused by the slide valve in the standby line = 0.1729 + 0.0022 + 0.0009 + 0.016 + 0.0308 = 0.2228 (MPa). Again, the driving force in the standby line is approximately equal to its resistance~~