(227d) Caustic Injection Relocation Project

Yanbu Refinery Department (YRD) operates a hydroskimming refinery with a capacity of 235,000 Barrels/day. The crude oil passes through three preheat stages (series of heat exchangers) before entering crude heaters. After the first pre-heat stage, water is added to the preheated crude oil prior to entering the desalters. A 3°Be caustic is injected upstream of de-salters to neutralize acids formed. Also, a 3°Be caustic is injected down-stream of the desalters for corrosion control. It was observed since YRD start-up in 1983 that second preheat stage exchangers has history of active corrosion and fouling problems. It was strongly recommended by Con-sultant Services Department (CSD) to implement the best practice idea which is relocating the downstream caustic injection from the down-stream of the desalters to upstream of the crude heaters to eliminate the corrosion and fouling problem in the second preheat exchangers. On av-erage, this relocation project is saving $1.55 MM/year in maintenance cost & Hydrocarbon loss. Furthermore, the paper will discuss the challenges faced after the relocating project and the lesson learned.