Who can help calculate the required heat exchange area for the cooler in the table below? Urgent urgent urgent
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Used to cool exhaust gas (mainly air, with a small amount of organic exhaust gas); it is a finned surface cooler with an air flow rate of 2500 m3/h. It is cooled using water at 5-10 degrees Celsius, and the expected temperature drop in the exhaust gas is 30-40°C (from around 50 degrees Celsius to around 20 degrees Celsius). The exhaust gas pressure is approximately 1000-2000 Pa. 304 material is used for this device; I’m not sure what the required heat exchange area is Could someone please help calculate it?
It’s better to get a book on Principles of Chemical Engineering; it doesn’t seem like something that can be manufactured by oneself, so it’s better to consult several manufacturing companies, as they are experts in this field. For reference.
Your question lacks sufficient details; it isn’t specified whether the air volume is given in cubic feet There is no cooling water flow either. There is also no specification regarding the heat exchange mode between the cold source and the hot source: is it co-current, counter-current, or cross-flow? From what you say, it seems that the flue gas flows through the shell side while water flows through the tube side, but there may be exceptions, and that isn’t specified either. It is recommended to turn to a professional heat exchanger manufacturer to handle this task; have them prepare the calculation documents for the heat exchanger. By being able to understand those documents, you can learn a lot as well.
I’ll do the calculation; send me the details on WeChat and I’ll help you work it out when I get back
A finned surface cooler appears to be a device for heat exchange with air; the fluid flows through the tube side, while fins are installed on the outside of the tubes to increase the heat exchange area. Common heat exchangers at the outlet of liquid nitrogen towers, as well as the radiators of air-cooled chillers. When amateurs create plans, they just try to cheat; following such a deceptive approach, they pick some heat exchangers from the second-hand equipment market and sell them to the owner at an arbitrary price. It’s better if there’s a profit left over, and if not, they ask the owner to pay more
The air volume refers to the exhaust gas under the operating conditions, while the amount of cooling water is determined based on the heat transfer rate; water is used to cool the exhaust gas
The calculation of the cooling water volume is based on the temperature difference between the inlet and outlet water; however, you haven’t provided this temperature difference here. Without it, it’s impossible to calculate the logarithmic heat transfer temperature difference, and thus the calculation cannot be carried out. With the same heat exchange surface, whether flow is in the co-current, counter-current, or cross-flow direction, the actual heat exchange efficiency varies as well. It is recommended that you first take a look at the heat exchange equipment and understand the prerequisites for performing heat exchange calculations before proceeding with those calculations. Fin plates also require certain parameters, such as their size and spacing. The amount you’re proposing now is much too low; if you’re not a designer, I suggest having the design department in your company give some advice.