Ammonia water evaporator calculation
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I have a question for everyone: for SCR denitration, 200 kg/h of an ammonia solution with a concentration of 20% is required. Now, an ammonia evaporation unit needs to be installed – how should the selection of this evaporation unit be determined? Power and heat transfer area: Ammonia water is heated from 20 degrees to 120 degrees using saturated steam at 170 degrees
Hello, I have found that the enthalpy value of 20% ammonia at 20 degrees is -22.49 kJ/kg, while its enthalpy value at 120 degrees is 2521.3 kJ/kg. Q = W(H2 – H1) = 200 * (2521.3 – (-22.49)) = 50875 KJ. P = Q/3600 = 50875/3600 = 141.32 kW
There is no need to consider the heat of phase transition; simply use the difference between the enthalpies of the two states. The above values were obtained from the AP1700 property database. I’m not sure if this calculation is correct; please advise, experts
This involves calculations related to phase transitions: saturated steam condensing into condensed water, and ammonia water evaporating into gaseous ammonia. It is difficult to find property data regarding the evaporation of ammonia water; please provide guidance. To know whether ammonia vaporization is possible, one needs to know its boiling point first. First, use the constant-pressure value of ammonia water* (boiling point – 20) to determine the heat absorbed by ammonia water; add the vaporization heat of ammonia water, and then use the constant-pressure specific heat capacity of gaseous ammonia* (120 – boiling point) to find the heat required for the vaporization of ammonia water. Please provide guidance
May I ask how you calculate it, expert?