Improvements in analytics and automation are proving effective in tackling some difficult challenges in batch processing.
In 2011, CP outlined the results of a six-month field trial by Emerson and Lubrizol of prototype online multivariate batch analytics software at Lubrizol's plant in Rouen, France (Figure 1) (Online Analytics Improve Batch Operations). The data analysis led to numerous production benefits, including overcoming a plugging problem due to batch-to-batch variations in component densities, and identifying a problem with the reactor cooling system.
DSM-Martek, Kingstree, S.C., subsequently carried out a similar trial — on an algae fermentation process for manufacturing its proprietary life'sDHA nutritional oil, which is used in infant formulas. It, too, was able to make process improvements based on the new data generated by the batch analytics software. For example, engineers analyzed all key control loops within the process and adjusted tuning settings for temperature and dissolved oxygen to enhance process control. DSM-Martek also found that product quality crucially depended on an interaction among several process parameters, including inoculation conditions, the extent of antifoam addition, and dissolved oxygen level. In addition, the early fault detection within the software helped assist the control room operator in maintaining both critical and non-critical process parameters.
"These projects were testing a prototype of what has become Batch Analytics software. This will be released fully as part of DeltaV 12, probably in mid-2013," says Dawn Marruchella, DeltaV batch product manager for Emerson Process Management, Round Rock, Texas, and co-author of the CP article.
Three companies now are testing the beta release of Batch Analytics: Lubrizol, Wickliffe, Ohio; MillerCoors, Chicago; and a major U.S.-based pharmaceutical manufacturer.
MillerCoors currently is the only one with the beta release fully installed — and already is reaping process benefits. For example, by comparing one line that uses the software with one that doesn't, the company has identified important control issues with the way a critical feed is being added to the process. It also has found that a trigger initiating a process step led to an overall reduction in line efficiency. Likewise, it was able to pin down the difference in the rate of operation of two similar production units to variations in steam pressure. In addition, MillerCoors determined a critical process parameter was too low over the course of a run. As a result it currently is implementing a point-of-use heat exchanger. Finally, the Batch Analytics software revealed that pH meters on the feed water system were out of calibration, which was causing control issues.
"Batch Analytics has really heightened the awareness of batches for these companies and there is a lot of enthusiasm for it. The potential savings as their experience grows and batch failures are reduced could be enormous. In a pharmaceutical process, for example, the loss of one chromatography batch could mean tens of millions of dollars," notes Marruchella.
One of the keys to success for all the users has been an initial focus on simpler small units, such as preparation tanks, that can generate a lot of batch comparison data quickly. "If you pick a fermenter to start with, the process can take two weeks to run a batch. So it takes a long time to start getting results. MillerCoors wanted to do this originally, but then decided that applying the software to a different process unit than runs more than fifty batches per week would give them faster access to useful data."
For one of the beta testers, end-to-end integration with its business systems was a critical part of the project. "There was a lot of work put into integrating the Batch Analytics product in such a way that the company can automatically access and use data stored in their ERP [enterprise resource planning] system and LIMS [laboratory information management system]. However, all of the testers have some data in an external system, be it an enterprise historian, a LIMS or an ERP system," notes Marruchella.
Ease-of-use is also an important issue. "It is important to make a product that doesn't need a PhD in statistical process control to operate it. The goal is to make it simpler for users to make more-informed decisions and better understand their process," she adds.
Simplicity should play a key role in batch automation, stresses Honeywell Process Solutions, Phoenix, Ariz. "We have done a lot of work on human factors so that, for example, if an operator's attention is drawn to a potential problem, it is very easy to navigate to product information and specification. This is becoming increasingly important as the number of recipes is proliferating. By having a very tight product spec, you get a better price and margin," explains Reading, U.K.-based Chris Morse, batch product manager.
"Operator mobility is another important issue, and how they access process information, for example, via an Ipad. This touches on the importance of usability. It is important to make the job of everyone involved much easier so that they can be more productive. So we are focused very strongly on human factors."