February 2008

Automation IT

Brewery taps higher control

Small brewer's system allows greater productivity, flexibility

Fast Forward

  • Brewer's control system upgrade turns into new automation system-in-a-box.
  • Small brewer gains big brewer efficiencies.
  • The goal: Maintain the optimum temperature profile for each beer variety.
 
By John Mallett and Todd Stauffer

When Bell's Brewery decided to upgrade the temperature control system on its 45 fermentation tanks in mid-2006, they were just planning on expanding their existing system of dedicated single-loop controllers for each of its tank control points.  

Instead, after taking a look at their options and what technology suited them best, Bell's opted to take a quantum leap forward by implementing a state-of-the-art process automation system for temperature control of its tanks.

What it ended up with is a brewery controls and automation system-in-a-box. It is a system optimized for small- to medium-sized breweries.  Implementing this system made Bell's one of the first craft brewers in the U.S. to put in place a temperature control system that rivals the efficiencies the big brewers gain. The new systems will also allow for the brewer to grow with scalability that encompasses all of the brewer's functions in one system.

Bell's Brewery, Inc., located in Galesburg, Mich., 10 miles to the west of Kalamazoo and 10 miles to the east of Battle Creek , is a privately held company founded by Larry Bell in 1983.  

Last year, Bell's produced 74,000 barrels of beer, ale, porter, and stout in 26 different brand varieties.  The majority of its production is ale, with brands like Bell's Oberon Ale, Bell's Winter White Ale, Bell's Amber Ale, Bell's Sparkling Ale, and Bell's Eccentric Ale. Bell's ranks as the 26th largest brewery in  the U.S., out of 1,400 brew houses, and the 15th largest craft brewery (based on 2006 sales, compiled by Information Resources (IRI) 2007, and released by the Brewers Association).  Bell's currently distributes its products in 12 states.

Craft and micro brewing represent the fastest-growing segment of alcoholic beverage sales in U.S. supermarkets. In 2006, craft and micro brew sales were 17.8% above 2005 and almost 65% higher than imported beer, the next nearest alcoholic beverage category in growth, according to IRI.  

Like many craft breweries, Bell's produced its first brew in a soup pot; in their case that pot was located in Larry Bell's home kitchen. For some time after, Bell's brewing set-up was a hodge-podge of different equipment, home-grown parts, varied control systems, and manual operations, with little holistic approach, which is similar to brew house set-ups in more than 50% of small- to medium-sized breweries.  In 2001, Bell's acquired a full-blown, full-process brew house-formerly Wolfgang Puck's Eureka brewery in Southern California-and installed it in Michigan, expanding it extensively in the process.  Additional projects, mainly in the fermentation area, have greatly enhanced the brewery's capacity. 

A system approach
 
Bell's had been using single-loop controllers on its fermentation tanks and was considering installing additional controllers to service all 76 of its tank temperature control points.  However, producing 26 different beers posed significant challenges in maintaining the optimum temperature profile for each variety, and as brew masters know, control of temperature in fermentation is absolutely critical to maintaining beer quality and flavor.  
The goal was to utilize technology to make better beer. Different beers will ferment at different temperatures as there are a host of flavor active compounds strongly influenced by fermentation temperature.  If one of our brands of beer ferments at the same temperature as another brand, the difference between those products would no longer be as distinct.  For us, precision in fermentation temperature control is integral to maintaining our high level of brand integrity."

Implementing this type of precision temperature control using a system of individual single-loop temperature controllers had its drawbacks, because the record keeping of tank temperatures is a manual, paper activity, prone to human error, and very labor intensive.

The initial interest centered on the fermentation process because of its ability to centrally control the temperatures of all 76 tank temperature control points from one location.  However, after reviewing the system, it also achieved a more precise level of temperature control than what we could ever achieve manually with single-loop controllers.  With the controllers we had been using, we would set our temperature parameters daily and then manually check the temperatures of our tanks once or twice a day.  The new system is capable of recording tank temperatures as frequently as every second and adjusting the process automatically to maintain the desired temperature profile. This was a new level of precision in fermentation temperature control.

System dynamics

The new system compresses the functionality of a distributed control system (DCS) into a compact industrial PC platform that features an integrated controller that operates independent of the PC. The system is a hybrid programmable logic controller (PLC)/DCS unit. It integrates new and existing automation systems from process, batch, discrete, and safety and devices within a single platform.  The system provides common tools for engineering, visualization, and plant-wide asset and maintenance management.  It also supports complete fieldbus connectivity.

The system also provided a complete information management system, so all of a brewery's fermentation data goes directly into the data historian. Bell's now has the capability for trending, archiving, and data analysis of its key process variables, as well as process debugging such as quick backtracking to determine the cause of problematic batches.  

Small breweries need to use technology to make the work more productive. These days, any company has to be agile and nimble and the new system allowed Bell's to react quickly to changes in production. When a new recipe comes up, the system allows the brewer to modify and adapt processing sequences and parameters such as volumes, temperatures, specific gravity, pH, and time intervals. 

Planning for future

One advantage with the new system is in the future all of Bell's automation controls can integrate within its infrastructure. It can run everything from grain handling through the brew house, fermentation, filtration, carbonation, pipe routing, all the way up to finished beer and packaging.

There is flexibility in standardization.  That is a very big issue for Bell's. For example, tying in the yeast production will allow the company to integrate a new propagation system, which is 20 times larger than the current equipment. Also, during the initial carbonation phase of the bottle conditioning process, cellar operators currently charge the system then manually take multiple samples over time, continually having to monitor and manipulate the gas flow to achieve the correct level of carbonation. With the installation of the new system, Bell's can automatically control carbonation to a desired set point on the fly.

Keeping it cool

Oftentimes, brewers do not always have the resources to smoothly manage temperature control in their fermentation process.  They have to maximize how much cooling can be done and how quickly they can achieve it. 

They are now capable of optimizing how much cooling can be done in the fermentation tanks and how fast they can realize it. Smaller brewers often face a problem because they stretch their cooling capacity to the edge. Fermentation creates heat, and the brewer wants to take that heat out of the fermentation process to control temperature, which comes from circulating a glycol solution in jackets around the tanks.  The demand for cooling can sometimes exceed the system's capability.  Because the system is continuously monitoring and automatically making adjustments, it can spread the heat exchange load out more evenly over time, eliminating temperature swings and maintaining more stabilized temperatures in the tanks. 

Although Bell's new system has just recently been installed, performance statistics are evident and significant.  The new fermentation control system has allowed the brewery a quicker throughput and reduced labor-hours, and the system is easy to operate.

The brewery reduced labor-hours as a result of putting in place the new system. Doing one to two manual checks per day, for each of our fermentation tanks, took quite a bit of time for two to three people. Now, the user can control all of it from one central location. Those newly found man hours are now being put to use on other areas in the brewery.  

ABOUT THE AUTHORS

John Mallett is production manager at Galesburg, Mich.-based Bell's Brewery. His e-mail is jmallett@bellsbeer.com. Todd Stauffer is manager of the SIMATIC PCS 7 line at Siemens Energy & Automation, Inc. His e-mail is todd.stauffer@siemens.com

 

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