How do you manage asphaltene fouling in crude oil heat exchangers?

Asphaltene precipitation causes severe fouling in crude preheat trains. Management strategies: blend optimization (compatibility testing between crudes), maintain adequate velocity and turbulence, control temperatures below critical precipitation points, use dispersant additives (polyisobutylene succinimide types), implement antifoulant injection, and optimize cleaning frequency based on fouling monitors. Design considerations: avoid dead zones, adequate tube velocity (>1 m/s), consider helical baffles for better flow patterns. Monitor with pressure drop trending and outlet temperature tracking.