One way to improve the overall equipment efficiency (OEE) of your spray dryer is to extend the duration between CIP cleanings.
The potential money to be saved can be significant. For instance, if you extend the duration between CIPs from 30-60 days, you’ve effectively cut your CIP cleanings in half throughout the year, leading to dramatically more up-time for your dryer.
Extend Duration Between CIPs
Caloris recommends examining several aspects of your production regimen to look for opportunities to extend the duration between CIPs.
Do you have unsteady regular startups and shutdowns and/or manual startups? This introduces the opportunity for build-up in your system, among other issues, which necessitates earlier CIP cleaning.
A better solution is to automate startups, changeovers and shutdowns. This leads to more consistency and less build-up (and therefore, less need for CIP).
Twenty-four hour dual feed systems have the lowest incidence of chamber wet-down and good tuning (commissioning) on an automated dryer startup has the lowest incidence of chamber wall build-up.
Caloris also recommends automation maintenance — always revert back to validated programs for your system to ensure consistency and proper cleaning intervals.
Another area of focus is your spray nozzle. Proper spray nozzle selection also contributes to smooth system operation and consistency in the need for CIP. A symmetric nozzle lance pattern is important, as well as using all of your nozzle lances for even drying and airflow. This eliminates cold and hot spots (where build-up is more likely to occur). For example, using only 5 nozzle lances on a 6 nozzle dryer is asymmetric and leads to hot and cold spots. Select the nozzle orifices such that you can operate on all nozzle lances and run a symmetric pattern.
Pay attention to your spray angles as well. Work with an application specialist from the manufacturer of your spray nozzle. (Good service is crucial — make sure your manufacturer offers good support. Contact Caloris for a list of recommended manufacturers.)
If you notice cone build-up, then a wider angle will be needed. If there is build-up on the wall, then a narrower angle is necessary. NOTE: weigh changes carefully if you are agglomerating.
Finally, consider your air disperser. Always use the full design airflow to get correct differential pressure and correct air distribution.
The airflow rates have been carefully selected by the designers of your system. Don’t reduce airflow to reduce through-put (reduce temperature instead). Likewise, don’t increase airflow to increase through-put (too much will drive the product to the dryer cone and increase build-up).
Caloris is Here to Help!
You can reap big benefits if you extend the duration between CIPs on your spray dryer, but system changes need to be carefully undertaken to avoid issues with product quality. Contact Caloris today for assistance with a system review and recommendations. Call us at 410-822-6900 or send email to firstname.lastname@example.org.
Coming Soon! Watch for the next article in this series “Spray Dryer CIP, Part 2: Shorten Dryer CIPs” for further tips on how to improve OEE on your dryer.