By Brith Isaksson, Global Food and Beverage Segment Manager, ABB Motion
The brewing sector accounts for around 4.8 percent of the electricity and fuel consumed by the food and beverage industry. Additionally, there is increasing pressure from governments, customers, and stakeholders for the brewing sector to reduce its carbon footprint.
Fortunately, modern motor technology, variable speed drives (VSDs) – also known as variable frequency drives or simply drives – and programmable logic controllers (PLCs) offer a straightforward path to enhanced efficiency.
Optimizing energy consumption
When it comes to improving energy efficiency in breweries, electric motors present a logical starting point. Electric motors are among the most energy-intesive equipment in any industrial facility. In the food and beverage industry alone, motor-driven systems account for approximately 17 percent of all electricity consumption.
Every stage of the brewing process that involves motors – from raw material intake to packaging the finished product – offers an opportunity to enhance energy efficiency. Electric motors are essential components in conveyors, mixers, pumps, decanters, mills, blowers, compressors, and more.
Upgrading to more efficient motors can yield significant energy savings. The highest efficiency class of motors today is synchronous reluctance motors (SynRM), which achieve IE5 "ultra-premium energy efficiency." By replacing older IE2 motors with ABB SynRM models, a facility can reduce its energy losses by up to 50 percent.
SynRM motors achieve this impressive level of efficiency in part by utilizing an ABB drive. Other motors can also be paired with drives to increase their efficiency. Without a drive, a motor's speed is controlled by throttling, which wastes energy.
When paired with the existing motor in a pump, fan, or compressor application, a drive can reduce power consumption by 25 percent or more. Despite this, across all industries, it is estimated that just 23 percent of the world's electric motors are paired with drives. PLCs can also contribute to improved efficiency by optimizing control systems and automating processes, leading to further reductions in energy wastage and enhancing overall operational efficiency.
Elevating process performance
In addition to improving energy efficiency, the enhanced control provided by drives also enables faster and more effective beer production. One issue for centrifugal pumps can be cavitation – the voids or bubbles created in a liquid by rapid changes in the local static pressure. Cavitation can reduce equipment lifespan by as much as 50 percent, while the resulting foam can affect beer quality. Furthermore, damage to the pump can cause costly leakages.
Drives with built-in anti-cavitation software offer a cost-effective solution. These drives continually monitor the pump motor's torque and speed without the need for additional sensors. The anti-cavitation software adjusts the motor's speed to stop cavitation and return to normal once conditions stabilize. This is especially useful for overcoming pressure drops as a tank empties.
PLCs enable further process optimization at every production step. Today's PLCs offer additional input and output (I/O) channels, greater scalability, and compatibility with a range of communications standards.
Ensuring superior product quality
Predictable, precise machinery is essential for successful brewing. For example, in the decanting phase, it is crucial to bring the separator up to speed rapidly and maintain a high speed while minimizing vibrations. For these applications, drives can utilize torque control to enable smooth start-up without the need for oversizing. Oversized equipment not only costs more to purchase but also requires higher OpEx and wastes power.
Where desirable, drives can also automatically switch to maximum torque once the motor exceeds a certain speed. When it's time to stop, the drive brings the screw to a gentle halt and can capture the kinetic braking energy and feed it back into the system, lowering energy costs.
Enhancing safety in breweries
In brewing, potential hazards include heavy machinery, dust, and hot liquids. Modern technology offers significant safety advantages. For instance, drives include a range of safety features, such as Safe Torque Off (STO), which brings a motor to a stop at the push of a button. For applications where dust – such as from malt – is present, motor-drive packages are available with dust ignition certification.
Motors designed for food and beverage applications are available with high ingress protection standards and smooth enclosures, ensuring ease of cleaning and maintenance. This limits the potential for bacterial growth or ingredient contamination. Washdown motors are ideal for these circumstances as they can last five times as long as standard motors in washdown environments.
Minimizing maintenance costs
Motors, drives, and PLCs can also streamline cleaning and maintenance. SynRM motors operate at a lower temperature, resulting in longer service intervals and a longer lifetime, and their magnet-free rotor simplifies maintenance.
Unexpected downtime also creates a risk to profitability. Sensors, monitoring equipment, motors, drives, and PLCs can all play a role in minimizing the need for unscheduled maintenance.
The soft pipe fill feature in ABB drives, for example, reduces unintended stress on pipes, sensors, and valves as pipes will be gradually filled in a controlled manner. Drives also feature under- and over-voltage protection, temperature and load warnings, and other features designed to reduce the chance of a breakdown.
PLCs enable real-time monitoring of important variables. By tracking data on equipment, the system can automatically identify impending failures with plenty of time for operators to intervene.
Brewing better beer with the right equipment
For examples of these benefits in action, we can look to two businesses: Tröegs Independent Brewing in Pennsylvania, US, and UK-based Bairds Malt.
Tröegs, which produces over 100,000 US beer barrels each year, faced issues with the drive controlling the yeast pitching system.The operators decided to replace it with an ABB drive.
The new drive provides significantly greater control than the old unit, including through simple visual sequence programming. Tröegs now uses the drive's repeatable sequences to ensure that the yeast pitching process is consistent every time.
At its Witham, UK site, Bairds Malt used a fixed-speed motor to agitate the barley during germination. This resulted in clumping, blockages, and unnecessary wear on the machinery. In some cases, the turner would get stuck and "jump" backwards, putting workers at risk.
The site resolved the issue by switching to four motors controlled by ABB drives. The drives can detect a blockage and help the turner clear the obstruction. The system is controlled by a PLC, which is mounted alongside the drives in a stainless-steel box. The PLC detects current spikes that indicate a potential blockage and slows the motors' speed. If this doesn't work after three attempts, the PLC alerts the operator. Bairds is installing similar systems at its other sites.
Brewing success with efficiency
Overall, motors, drives, and PLCs are critical to supporting the beer industry's continuing growth. They enable greater energy efficiency, better processes, higher product quality, safer operations, and lower maintenance costs – a combination that's worth raising a glass to!
For further information, please visit: https://new.abb.com/drives/segments/food-and-beverage/brewery
