Chemical Engineering & Technology, Vol.38, No.12, 2226-2234, 2015
Fouling Mitigation in Tubular Exchangers Using Various Projectiles: Deposit Removal Mechanisms
Fouling of different types can severely compromise the thermal efficiency of heat exchangers. The removal of CaSO4 deposits was experimentally investigated when projectiles of various types were propelled inside a heated tube. Projectiles were injected at a constant injection rate from the beginning of the fouling process until an asymptotic fouling resistance was approached. The removal rate was found to be inversely proportional to the fouling layer thickness. The removal of deposits due to exerted shear forces by projectiles decreased as the fouling layer developed due to hardening and intensification of the deposit layer. The results indicate that the asymptotic behavior is mainly due to the decrease in the deposition rate as the fouling layer hardens such that it becomes equal to the removal rate and not the other way round.