Unit conversion, tons per hour and cubic meters per hour
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Known operating conditions: concentrated sulfuric acid pump, specific gravity of 1.83, head of 20 meters, flow rate of 60 tons per hour. I checked the manufacturer’s selection guide, and the pump flow rates are given in cubic meters per hour. 1 cubic meter of water is approximately equal to 1 ton. However, the density of sulfuric acid at 1 cubic meter is 1.83, so it weighs around 1.83 tons. That’s how I understand it; I’m not sure if it’s correct. Can we simply choose a pump with a flow rate of 60 cubic meters per hour? ? ? ?
No, if a pump with a flow rate of 60 m3/h is chosen, then it will be capable of transporting 60*1.83=109.8 tons per hour of concentrated sulfuric acid. This is not necessary from a process perspective, and it also results in energy waste. It is appropriate to choose a pump with a flow rate of 60/1.83=32.8 m3/h
Thank you. So you mean that the conversion is definitely necessary? We need 60 tons per hour, and based on that, the manufacturer’s calculation should be 60/1.83 = 32.78 cubic meters per hour.
Yes, these operating conditions and requirements are provided to the manufacturer, who will carry out the calculations themselves
Do you need volumetric flow rate or mass flow rate?
This post was last edited by oceans on 2019-6-22 at 16:39. Why hasn’t anyone considered the head? Density also affects head. For pumps that transport liquids with a viscosity greater than 20 mm2/s (or a density greater than 1000 kg/m3), it is essential to convert the pump’s performance curves obtained from water-based tests into curves corresponding to that viscosity (or density). In particular, careful calculations or verifications must be carried out regarding the suction performance and input power
The relationship between head and pressure is given by H = (p2 – p1) / ρg + (v2² – v1²) / 2g + z2 – z1, where H is the head in meters； p1, p2 —— Pressure of the liquid at the pump inlet and outlet, Pa ； v1, v2 —— flow velocity of the fluid at the inlet and outlet of the pump, m/s ； z1, z2 —— inlet and outlet heights, m ； ρ —— liquid density, kg/m3 ； g — gravitational acceleration, m/s2.
Given that the operating condition is 60 tons per hour with concentrated sulfuric acid, can a pump with a flow rate of 60 cubic meters per hour be selected directly? ? ? ?