Considering all previous ...

Published August 1, 2018 15:08 by Rafael Gay-de-Montella MSc PEng, Water Wastewater Treatment Expert, Oil-Gas, Tailings, Boilers, ZLD; Evaporators, Sludge

Considering all previous answers could be correct, there is also the possibility of tubes with incrustations on areas not well cleaned... the effect of heat transmission is of great importance, specially on the deepest section of tubes.