What is the natural air circulation volume inside a 110-meter-tall tower?
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This post was last edited by sd435235633 on 2010-9-18 07:03. Experts from Haichuan: The tower is 112 meters high with a diameter of 13 meters; it produces 13 T of compound fertilizer per hour. There is an urgent need for a formula to calculate the natural air intake volume inside the tower. The structure of this tower is the same as that of other towers of this type – there are 6 natural air inlets near the bottom of the tower, and a natural air outlet at the top. Please help calculate how many cubic meters of air per hour flow through those 6 natural inlets. It would be great if you could also provide the calculation formula. Haichuan Forum is full of talented people, including many who specialize in designing such towers; those who know the answer please let me know! Thank you! ! !
Suggestion: When studying the principles of chemical engineering, apply Bernoulli’s equation; the driving force comes from the pressure difference between the top and bottom of the tower, while the calculation of resistance requires reference to relevant materials or estimation
Friend, could you help calculate the volume of natural air flow entering this tower, in m3/h? Thank you! ! !
It seems one can’t take things for granted. The air volume is primarily based on heat balance. The calculation formula is as follows: Q = Q_settling + C(t2 – t1) × 1000. Q_settling: the heat released when the compound fertilizer sets, which is equivalent to the crystallization heat. Reference urea: 57.8 kcal/kg of urea ； C: The specific heat capacity of solid compound fertilizers, whose value varies with temperature. Reference urea: average value of 0.5 kcal/kg of urea ； t2, t1: respectively the temperature of the molten compound fertilizer upon entering the tower and the temperature of the finished compound fertilizer upon exiting the tower, in °C. Q=Qc＝V×ρ×ΔI Where V is the volume of cooling air, in cubic meters ； ρ: Density of cooled air, which varies with temperature and pressure; it can be found in handbooks on the physical properties of materials, and generally a value of 1.2 kilograms per cubic meter can be used ； ΔI: The enthalpy difference of the cooling air as it enters and leaves the tower, in kilocalories per kilogram of air; this value can be determined using the inlet and outlet temperatures of the air, as provided in handbooks on the physical properties of materials or in textbooks on chemical engineering principles. Due to the uneven flow of cooling air within the tower, a coefficient of 1.1–1.2 is used; thus, the actual cooling air flow rate V_actual is calculated as 1.1–1.2V.
First, you need to provide the temperature of the particles as they leave the tower, the temperature of the gas exiting the tower, and the granulation temperature. You can refer to my articles in \"Phosphatic Fertilizers and Compound Fertilizers\": Defects in the design of high towers, etc