What is carbon raschig ring?

2022-12-13

The carbon raschig ring is made of colloidal graphite powder, which has the advantages of good corrosion resistance (better hydrofluoric acid resistance), relatively low cost, and is widely used in packed towers to improve separation efficiency. In foreign countries, carbon Raschig rings is also called grahite raschig ring, which are mainly prepared by high-temperature graphitization of coke and asphalt into graphite tubes and then intercepting method. The production cycle is long and energy consumption is large. However, there are few reports on graphite Raschig rings in China.
 
Phenolic resin is used as the adhesive, and graphite powder is cured, dried, crushed, sieved, pressed, and heat treated. Selection and dosage of the adhesive. In foreign countries, carbon raschig rings are made from coke and asphalt by high temperature sintering at 2000~3000 ℃. It has been reported that under the same conditions, the bonding effect of phenolic resin is the best. This is due to the residual carbon formed in the network structure when the phenolic resin is heated, which improves the mechanical properties of the product. However, too much addition leads to the decrease of porosity. According to the chemical characteristics of phenolic resin, ethanol is used to dissolve phenolic resin and urotropine. After complete dissolution, graphite powder is added and fully mixed. After curing for a period of time, it is placed under an infrared lamp or an oven with a ventilation device to dry completely, and then it is crushed by a ball mill to pass the 80 mesh sieve. We found that the length of ripening time affects the mechanical properties of Rashing ring. If the ripening time is too short, take 3 days for ripening in the experiment.
Press forming, test the influence of different pressures on the performance of Rasheed ring, and find that when the pressure is less than 10 MPa, the crushing strength is low, and the porosity is high; On the contrary, the pressure is too high (20M Pa), the porosity is low, and stress fragmentation occurs.