In Hydrocracker fractionator, ATF draw temperature is 220 Deg C which is going to side stripper. Side stripper is having reboiler which is taking heat from diesel pump around. The reboiler outlet temperature is about 250 Deg C.It is observed that when the ATF draw increases beyond 50 M3/hr. it is failing in Flash while maintaining the temperature condition same. Column is operating at 2.1 Kg/cm2g pressure.
Where is the problem?