(155c) Fouling Mitigation of Quench Tower System

Especially gas cracking plants are sensitive to fouling in the quench water section. One main fouling mechanism in the quench tower and in the related equipment is the accumulation of material with a high pour point. Fouling can be avoided or at least significantly reduced if the pour point of the hydrocarbon phase can be lowered below process temperatures of the system.

To mitigate fouling for the Borouge Plant in Ruwais Abu Dhabi Linde Engineering has built a redistillation unit. In this unit the heavy hydrocarbon product of the plant is fractionated and a hydrocarbon fraction is routed back to the quench tower for pour point adjustment. Compared to the former performance of the quench tower measured process parameters indicate that an increased run length of the quench tower can be achieved.