Monday, June 28, 2010
Continuous Thermal Processing starts with the the basics of "how much heat" for "how long" it takes to kill particular bacteria and accomplish a pasteurization or sterilization process, and really doesn't stop from there.
Everything from flash pasteurizer P&ID diagrams to single heat exchanger and other component specification, its complete with the calculations which derive a number of equations from scratch, and goes on to quick reference tables.
The book was based on an early version and has expanded its range by new authors in this new edition to include far more than dairy applications. Its found to be extremely thorough including later sections in heat exchanger fouling, and machine CIP.
This book is available through Amazon.Com by clicking the link below. Note that it is a a part of the "Food Engineering Series" which are all equally as interesting.
Continuous Thermal Processing of Foods: Pasteurization and UHT Sterilization (Food Engineering Series)
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Sunday, June 27, 2010
Conversions from Walking Beam pasteurizers to belt generally do not cost justify until the machine structure has weakened to a point where the machines life extends by putting in belt. Even at that makes a pasteurizer conversion from walking beam to belt justify is not the bed conversion itself, but the energy improvements and other packaging improvements which can be done while you’re in the machine.
A near topic has to do with a number of items and improvements which could be done while a used pasteurizer is being installed or relocated.
This is an expansion on the previous articles on purchasing used pasteurizers: Guide to Purchasing a Used Pasteurizer (Tunnel) and, Buying a New (or Used) Tunnel or Flash Pasteurizer.
This article is slightly different – covering the great opportunities that exist when purchasing and installing a used pasteurizer, used warmer, or used cooler.
In the process of purchasing and installing a piece of used machinery – or doing a pasteurizer bed conversion - there are innumerable opportunities which can be done for relatively negligible expense while the machine is being relocated and re-installed.
1. Full Regeneration – Regeneration is the number one energy saving feature on a pasteurizer and can save more than $100,000 / year. Regeneration is not to be taken lightly and should be studied and optimized.
2. Pasteurizer Belt, Shafts, & Bearings – These parts wear and create a significant amount of work to replace after the machine is in service. This is low hanging fruit. After the belts, Shafts, and bearings are in operation, the cost of replacement will double.
3. Single Deck Sprays – Access and maintenance to lower deck sprays in the pasteurizer is a challenge after installation. Eliminating lower deck sprays is a positive step that will require the speeds of the decks and other adjustments, including (effectively) re-commissioning the pasteurizer. Chances are this change will not get made after the machine is back into production.
4. Electrical Panels – if you can’t bring yourself to demo that panel and replace it with a new one before the machines installed – do you really believe it will happen after its fully wired? If you need it, it’s a good time to get a new electrical panel and drawing package with matching field tags.
5. Spray Issues – Broken nozzles, pans, and overhead overspray issues will cause the machine to chew down utilities unnecessarily.
6. PU / Process Control Improvements - Ensuring the process is proper and there is no overspray or communication of water between zones.
7. Instrumentation Standardization and Replacement – This is your chance to standardize on components that make sense in your plant.
8. Condensate Recovery – See Article on Condensate Recovery
9. I/C Wedge – great opportunity if you have no round containers on the infeed.
10. Insulated Top and Side Covers
12. Chemical Dosing System Upgrades - Crude control of dosing can cost chemical spend as well as eat away at the pasteurizers stainless steel.
14. Utility Monitoring Package
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