A Caloris customer wished to extend the duration between CIP cleanings on two of their spray dryers from every 28 days to 90 days or more. A reduction in the amount of scorched particles would help accomplish this goal.
Caloris proposed the following tactics:
- Automation improvements to improve operational consistency of the production start-ups and shutdowns of the dryer to reduce wall build-up and scorched particles.
- Nozzle lance optimization to reduce build-up and scorch
- Air disperser modifications to improve airflow patterns to reduce wall build-up and scorch.
- Operations support to optimize operating procedures
Among the changes made, our engineers modified the air dispersers to make the air more laminar across the sprays. Cooling bed air flows and temperatures, inlet fan speeds and chamber pressure were also checked and adjusted. We eliminated intermediate nozzle flushes. Run durations were increased to 32 hours from 24 hours.
To improve the automation, Caloris identified the incremental changes needed in the timers and sequences of the current system for production and CIP.
For the feed system optimization, Caloris identified and implemented changes to spray nozzles, feed filters, the stuffing pump and related areas of the dryers.
The above modifications along with the process engineering and operations site support culminated in training for plant staff that covered the changes to the operating procedures. In the end, the targets were easily achieved and exceeded.