Discussion on the application effects of graphite heat exchangers

Advantages include good corrosion resistance, high thermal stability and thermal conductivity, low coefficient of thermal expansion, no contamination of the medium, and good chemical stability. The downside is that it’s quite bulky. The price is related to the heat exchange area. The maximum design temperature is 150°C. The pressure on the tube side is less than 0.3 MPa, while it is 0.5 MPa on the shell side. The technology in southern China is better than that in the north; many manufacturers in Nantong have a technology that is not much different from that used abroad.

Advantages: 1. Excellent chemical stability: resistant to acids and alkalis. 2. High thermal conductivity: second only to copper and aluminum; more than 5 times that of stainless steel, and more than 2 times that of carbon steel. 3. Low linear expansion coefficient: (5~27)*106*1/°C; it can maintain its original shape and mechanical strength at high temperatures. Compared to corrosion-resistant materials such as ceramics, glass-lined steel, and high-silicon cast iron, it possesses much higher thermal stability and is capable of withstanding thermal shock well. 4. The surface of shaped graphite components does not tend to form scale; its “affinity” with most media is extremely low. 5. Good machinability: aside from being unable to be rolled or forged, it can undergo various machining processes. 6. Low density of graphite: it results in lighter weight compared to corresponding metal components. The highest operating temperature achievable abroad is 430°C℃ ； Pressure range: complete vacuum to 16 kg/cm2 ； Heat exchange area range: 0.1~1500 m2 (lumped porous type)

1# lxq700918: The first two advantages were mentioned by the senior managers, so I won’t repeat them. I’ll answer the original poster’s question directly: it can withstand a pressure of up to 1.0 MPa, and temperatures ranging from -20 degrees to 180 degrees. Currently, tubular graphite semi-water gas coolers are used in fertilizer production, and manufacturers of graphite equipment in the north are 10 years more advanced than those in the south (Nantong-based manufacturers may be more advanced in producing porous equipment for precision factories). Its performance is now seen across fertilizer companies nationwide, and its technology has been recognized by clients both at home and abroad. In fertilizer plants, it is mainly used for cooling semi-water gas; after desulfurization, it is introduced at the inlet of the first stage of the compressor. Together with a graphite semi-water gas cooler, it can reduce the temperature of the semi-water gas by 20 degrees, thereby increasing the ammonia synthesis yield by approximately 6%. The price of this equipment is lower than that of stainless steel heat exchangers, and it is roughly on par with carbon steel ones. The cost can be recovered 1.5 times over the course of a year. It has been verified by many manufacturers. In an economic crisis, energy conservation and emission reduction are the only options; we can’t control the market, but we can control costs – that’s all we can do.

4# Used for heat exchange in urea production, to cool carbon dioxide; its principle and effectiveness are the same as those of semi-water gas cooling, and it is also used at the inlet of the first stage of the compressor. For inquiries: Engineer Zhang at 13698674969