Sugar is one of the purest ingredients in nature. Found in fruits, nuts, vegetables, and other edible plants, it’s made through photosynthesis, a process by which sunlight naturally transforms it into an edible energy source. A natural carbohydrate, sugar is mainly produced from sugar beets and sugarcane. Sugar beets are a type of root vegetable that can grow in cooler climates, while sugarcane is a tropical grass that can reach heights of up to 20 feet (about 6 meters). Sugar beets and sugarcane contain proportionately more sucrose – the main ingredient in white sugar – than any other plants, which is why they’re used for the large-scale manufacturing of sugar.

However, processing sugar from these plants requires refining to remove impurities and concentrate the sucrose into sugar crystals. Machinery used in sugar production must first process the plants into raw sugar before refining it. Equipment for sugar plants is used to remove all the gums, lignin, polysaccharides, proteins, starches, waxes, and other adulterations that may affect the color, taste, and yield of the final product. Sugar plant machinery is used for heating, clarification, and other energy-intensive processes to refine sugar beets and sugarcane into processed sugar.

Sugar Plant Machinery Applications

Each type of sugar plant machinery performs a specific task during the refining process, transforming raw sugar beets or sugarcane into refined sugar. These machines enable manufacturers to produce sugar economically and on a large-scale basis. Different sugar plant machinery is used for each of the processes. It involves first extracting the juice from plant material and then clarifying it. After clarification, the juice is concentrated and then crystalized, after which the remaining liquid is separated from the sugar crystals. The final product is then dried before being packaged and distributed.

Different types of sugar plant machinery include:

  • Juice extraction equipment: This type of sugar plant machinery is used to crush raw sugar beets or cane and extract juice, including lump crushing equipment and various types of milling machines.
  • Juice clarifiers: Used to remove impurities and solids, clarifiers help ensure the juice is separated from unwanted materials to clarify the liquid.
  • Evaporators: Used to concentrate juice, this type of sugar plant machinery removes excess water by heating the juice so that water evaporates and turns it into a thick, condensed syrup.
  • Crystallizers: These machines turn the syrup into sugar crystals by regulating how it cools, using precise temperatures to allow sugar crystals to form into the required size.
  • Centrifuges: As not all the liquid evaporates, centrifuges are used to separate sugar crystals from the remaining syrup through the use of centrifugal force.
  • Drying machines: The remaining moisture is removed by sugar plant machinery that dries the sugar crystals before packing the sugar for distribution while also ensuring that it flows freely and doesn’t clump.

Other processes are also used to make various grades of finer sugars.

Considerations When Choosing Sugar Plant Machinery 

It’s important for a manufacturer to consider numerous factors before putting together a system to produce sugar. Plant machinery needs to handle the amount of raw material that needs to be processed at each production stage. Additionally, sugar plant machinery must extract and clarify juice effectively, using precise processes to control crystallization before finally separating and drying the sugar crystals. Plant machinery at a sugar processing facility should work optimally and seamlessly to reduce unplanned downtime while also ensuring an efficient process to keep operational costs low.

When selecting sugar plant machinery, it’s important to consider: 

  • Capacity: A manufacturer should take into account the volume of raw material they anticipate processing, along with the amount of total production desired.
  • Durability: Since sugar production is demanding on sugar plant machinery, robust and well-made equipment is less costly over time, as there will be fewer breakdowns that result in downtime.
  • Energy efficiency: The more energy-efficient sugar plant equipment is, the lower operational costs and the more environmentally friendly sugar production will be.
  • Maintenance: Equipment that’s easier to maintain means more uptime, resulting in more efficient operations.
  • Manufacturer support: Accessing technical support promptly helps optimize a sugar plant’s processes.
  • Mechanical efficiency: The more quickly and effectively equipment operates, the lower the cost of processing becomes.

But besides these more ordinary aspects that might apply to any plant equipment, modern sugar processing machinery also benefits from technology. Automation has improved the efficiency and accuracy of equipment by replacing manual processes, while digital technology has made processes quicker and more reliable. The rise of the Industrial Internet of Things (IIoT) – often associated with “smart” factories – has brought real-time monitoring through connected and integrated sensors, which enhance control and even allow manufacturers to predict when machinery will fail more accurately.

In conjunction with this hardware, software integration into sugar processing plants has become progressively more common. This includes implementing programs that utilize machine learning – a branch of artificial intelligence (AI) technology – that further optimizes processes and energy consumption to increase efficiency, leading to a more eco-friendly environmental footprint for sugar plants. Machinery specially designed for sugar production is becoming more advanced as original equipment manufacturers (OEMs) like Prater Industries develop sugar plant equipment that further increases the quality of the product while driving the industry towards greater productivity and sustainability.

Sugar Plant Machinery by Prater Industries

As explained above, sugar plant machinery needs to deal with a gamut of processes, each of which is necessary to refine raw sugar into an ingredient that can easily be added to other foods. Prater Industries manufactures a range of equipment that can be customized to meet any number of material handling applications necessary in the sugar processing industry. These include rotary airlock valves, lump breakers, and air classifying mills.

When used in conjunction with other systems for processing sugar, plant machinery like Prater’s lump breakers helps deagglomerate material without reducing the natural particle size of the grains. Also referred to as lump crushers or flake breakers, lump breakers also prepare sugar for easier conveying. As it’s naturally hygroscopic, sugar often forms into lumps during storage or processing, especially when there’s insufficient humidity control in a sugar plant. Machinery within sugar processing systems often starts off with a lump breaker to unload and condition raw sugar for further processing.

Also known as rotary valves or rotary airlocks, rotary airlock valves made by Prater are a vital piece of equipment within a sugar plant. Machinery like grinding mills typically require rotary valves for metering bulk material before milling, and they’re also used to feed into a pneumatic conveying system. This ensures downstream sugar plant equipment receives a steady and controlled flow of material. Working as an airlock, rotary airlock valves also maintain a pressure differential at the point where the pneumatic circuit and storage container meet. Though not completely airtight, the pressurization or vacuum of a rotary airlock valve maintains convey sugar along during processing.

Prater’s air classifying mills are used for making finer types of sugar. Plant machinery that needs to make fine sugar grades like confectionery sugar or fondant sugar will normally include an air classifying mill or another type of mill that performs similarly. These mills utilize impact milling along with an internal air classifier to separate and recirculate fine particles according to size. They’re particularly used for adjusting the size of sugar particles. Like many more advanced sugar plant machinery, air classifying mills use a variable frequency drive (VFD), which helps lower energy costs to make the facility more efficient while enabling more precise particle sizes.

Prater Sugar Plant Machinery for Fine Grinding

In addition to the above sugar plant machinery, Prater also makes fine grinders that are well-suited for making confectionary grades from raw granulated sugar. Plant machinery that can reduce these grains into a powder through impact and shear forces can produce extraordinarily tight particle size distributions, reducing material to a fineness of 400 mesh (37 microns). Often used for baking, these grades that include 6x, 8x, and 10x confectioners sugar can be made using Prater’s fine grinders.

Prater’s two styles of fine grinder are:

  • M Series Fine Grinder: Designed with a tight tolerance between the grinding mechanism and rotor blades, this machine can achieve greater uniformity and a finer grind; proficient in processing heat-sensitive products like sugar, plant equipment can be easily matched up with one of six sizes of the M-series fine grinder, offering from 3 to 250 horsepower.
  • 10-Bar Fine Grinder: Used in conditions that can lead to conflagrations or even explosions, these mills can resist shock up to 145 pounds per square inch (psi), or 10 bar; typically, the 10-bar fine grinder is used to grind finer sugars from 4x to 10x within a tight particle size distribution, while also including an extensive bearing monitoring system.

Both these designs are made to work within a pneumatic conveying system, able to handle heat-sensitive material like sugar while providing excellent dust control.

Prater Sugar Plant Machinery in Action

Prater is known in the material handling industry for providing innovative engineering solutions, including for this project where a customer wanted to overcome deficiencies in their current system.

The customer wanted to convey and grind sugar at a continuous rate of 3000 lbs. (about 1360 kg) per hour to a 6x grade of sugar. To achieve this, plant machinery needed to bring 93.5 percent of sugar granules to under 200 mesh (74 microns) – the typical size of 6x sugar. The rate of metering needed to be consistent while also conveying it into a filter receiver and ensuring no metal contaminants entered the production stream.

There were significant problems with the existing sugar plant machinery. It was not performing as well as it should, and the system often had bearing failures. Additionally, sugar was caramelizing within the mill when grinding stalled. Another problem included the heat at which the system ran, at temperatures that were too high at points during the conveying and grinding processes. Reduced air volume in the system’s piping and tubing was also a persistent problem. In addition to these problems, the facility needed to comply with requirements in order to prevent and suppress conflagrations.

The solution developed by Prater’s engineers included an upgrade to an M-36 fine grinder with a 25-horsepower motor from an M-21 model, which has a 15-horsepower maximum. For consistent metering, two heavy-duty PAV-6 rotary airlocks were incorporated into the system. The discharge hopper for the mill was replaced by a low airflow hopper, which eliminated the need for air intake under the mill to lower the amount of air the system required.

With the air intake below the rotary feeder no longer needed, engineers replaced piping for the existing line that introduced corn starch into the powdered sugar with tubing that had a 4-inch (10.16 cm) outside diameter. A branch damper was installed upstream of the starch feed. The mill air intake was replaced by a long radius elbow that had a 5-foot (1.524 m) vertical with a high-capacity air intake filter.

To lower the proportion of air to cloth, the system was upgraded with a larger dust collection bin. A new pressure blower was also installed to lessen tension on the grinder, which in turn would allow longer intervals between maintenance inspections for the bearing spindles. Finally, the return line was rerouted to fit into the new filter receiver rather than the feed hopper.

To learn more about our sugar plant machinery and engineered solutions for sugar production, contact the material handling experts at Prater.