Plate heat exchanger calculation
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This post was last edited by jinfu2008 on 2015-9-19 at 10:59. How many tons of water can be heated from 15 degrees to 25 degrees using 1 ton of steam at 0.5 MPa? There is no time limit; it just needs to be used up with one ton of steam
This post was last edited by gn_1984 on 2015-9-16 at 10:55. It can heat 50.6 tons of water; private contact within the site is required.
Q_vapor = m_vapor × H; Q_water = c_water × Δt. According to the law of conservation of energy, Q_vapor = Q_water, so m_vapor × H = c_water × Δt. Both H and c can be looked up, and then the value can be calculated. Is it really appropriate for the original poster to ask such basic questions?
It’s not that I don’t understand; I can calculate that it’s 60 tons. But the customer told me that another manufacturer of heat exchangers calculated it at 500 tons, which is why I’m asking
It should be 50.6 tons; the original poster might have checked the parameters incorrectly. I’m also really envious that you have such good competitors who were able to calculate 500 tons.
The original poster’s calculation is correct. 59.63T, approximately 60T.
What temperature have you set for the steam outlet?
There’s no need to consider this. Do you know how many kilocalories are in one ton of steam? You can also calculate how many kilocalories it takes for water to rise from one temperature to another, right? If you know both of these, just do the reverse calculation and you’ll get it!
The enthalpy of vaporization for saturated steam at 0.5 MPa (absolute pressure), as I found, is 2110 kJ/kg (approximately 504 kcal/kg). Considering only the latent heat (that is, assuming an exit temperature of 151°C), the heat released by 1 ton of steam is 2110*1000 = 2.1*10^6 kJ. The specific heat capacity of water at 15/25°C, according to my research, is 4.19 kJ/kgK. Applying the law of conservation of energy, the mass of water is equal to heat divided by temperature difference: 2.1*10^6 / 10 / 4.19 = 50119 kg. Please check if there’s any mistake in my calculations. Thank you. Additionally, if the steam outlet temperature is below 151°C, it is necessary to calculate the sensible heat; the calculation of sensible heat is certainly related to the steam outlet temperature, so please consider this further. Thank you
It can still heat water up to 15 degrees even when connected to 151°C hot water from above; after heat exchange, the temperature becomes 30 degrees, so it can still heat 12 tons of water, for a total of 62 tons