Mehran Sugar Mills, located around 250 kilometers from Karachi in the south of Pakistan, is one of the country’s oldest and most important sugar mills. Every year, the facility crushes over 1.5 million tons of cane to produce the well-known Chashnik brand of granulated sugar.
But a few years back, it started to suffer from an issue with process downtime that was causing production losses running at $4,000 an hour.
The issue was with the Programmable Logic Controller, PLC that controls the operation of one of the facility’s six sugar centrifuges.
Centrifuging is a key stage in the refining process in which the syrup resulting from the crushing, evaporation and crystallization phases is spun at speeds up to around 1,000 rpm.
This forces out the liquid to leave behind sugar crystals. The significant downtime caused by the faulty PLC was a major concern since the sugar cane harvesting season runs for only five months of the year, from November to March.
“The sugar season in Pakistan is short, so sugar mills demand the highest levels of availability and reliability,” explains Muhammad Kazim, ABB project leader for the sugar centrifuge PLC revamp project at Mehran Sugar Mills.