Design of gas-gas plate heat exchangers (process discussion)
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Everyone, I am planning to design two plate heat exchangers for gas-to-gas heat exchange – one for experimental use and the other for actual engineering applications. I have some questions I would like to ask you all. The figure shows a sketch of the gas plate exchanger used in experiments. The flue gas and air flow separately, with the flue gas on one side of the plate and air on the other; the shaded area represents the part that needs to be sealed between the two plates. My question is: (1) Is the material used for sealing this area also metal? If welding is used to connect the sealing plate to the heat exchange plate, which welding method offers better corrosion resistance? (2) If non-metallic materials are used for the ports, and these materials need to be able to withstand high temperatures (200°C is sufficient) as well as resist deformation, what materials can be used? And how should this sealing material be connected to the heat exchange plate? The diagrams in Chapters 2 and 3 introduce this type of counterflow heat exchanger; what might be the sealing materials used? And how are these sealing materials connected to the heat exchange plates? (3) If any of you have additional information on this topic, could you please send it to 312895434@qq.com? Thank you to all those who can help with answers
Additionally, non-metallic materials are also required to be corrosion-resistant, as the flue gas is derived from natural gas
You use non-metallic materials mainly for corrosion prevention, right? Not many non-metals can withstand 200 degrees; it is recommended to use stainless steel!
Also, the temperature of flue gas is usually more than 200 degrees, right!
Both the heat exchange plate and the sealing plate are made of stainless steel. I’m now looking for a way to connect the sealing plate and the heat transfer plate directly, without using welding; is it possible to achieve this with some kind of non-metallic material?
There is a condenser in front of this heat exchanger; the temperature of the flue gas when it reaches this heat exchanger is below 200 degrees
What material is used to block the shaded area? This idea is a bit strange; even if it’s feasible, it might be quite troublesome from a technical standpoint. In fact, full welding should be used; if it is made of stainless steel, fusion welding is appropriate. The air flows on both sides travel through separate channels, allowing the heat exchange temperature to reach 800–1000°C. In cases where higher temperatures are required, an expansion mechanism can be used at the connections between the flanges to absorb the thermal deformation of the plates
Special tempered glass is used to prevent corrosion and to maximize heat recovery. We currently produce glass plate tubular heat exchangers, which have been successfully used in actual applications with excellent results
It can be directly used to create fully welded plate-type air preheaters, and is currently widely employed for recovering waste heat from flue gases in the high-temperature sections of industrial furnaces. Low-temperature dew point corrosion areas can be addressed using enamel-lined pipes, cast iron plates, silicon carbide pipes, and similar materials
What is the title of the book whose screenshot you showed? Thank you