Falling-film evaporators – role in steam saving (a perspective of Almoiz Industries, Pakistan)

The energy efficiency of a sugar mill depends to a large extent on the performance of the evaporators. Falling-film evaporators (FFEs) have the required characteristics to work on a narrow ΔT to improve the steam economy. Almoiz Industries set up a state-of-the-art project in Pakistan having a low steam and power consumption. A complete set of seven FFEs was installed. Operational problems such as scaling are discussed. All vapors from the 1st effect to the 5th, including condensate, are used to heat juice and crystallize sugar to reduce steam consumption. A steam consumption of 35 kg/100 kg of cane and 33 kW/t of cane electrical consumption is achieved at the maximum rate of cane crushing. Operational data over the last campaigns are given. Saved bagasse can be used for power export and other allied businesses.