Coffee Conveyor Selection Guide
Looking for the right conveyor for your coffee product? Manufacturers and roasters are moving away from using traditional, open bucket elevators and belt conveyors for moving ground coffee and coffee beans due to both hygienic and layout challenges. Instead, coffee producers are opting for more efficient, hygienic, totally-enclosed and flexible conveying systems.
Enclosed, hygienic coffee conveyor options include flexible screw conveyors, aeromechanical conveyors and tubular cable drag conveyors.
But which conveying system is right for your coffee product? The type of coffee product you wish to convey, the coffee product end customer (ie. commercial vs. specialty – how much does whole bean breakage matter?), operational needs (ie. energy efficiency), budget and facility layout must all be considered.
Coffee Conveying Considerations by Product
Green unroasted beans, roasted whole beans, ground coffee and coffee mixes all come with characteristics and challenges that must be considered when selecting the right conveying system.
Green, Unroasted & Roasted Whole Beans
Unroasted, or green, coffee beans are very fragile in their raw state. A gentle conveyor that minimizes bumping, twisting and grinding will be ideal to protect the beans from breakage. Broken beans means waste and wasted dollars early in the coffee production process, unless the beans can be separated and then delivered as a final ground product. Additionally, the conveyor will need to be constructed to hold up to the abrasive wear of processing whole beans.
Like green beans, roasted whole coffee beans are very fragile and thus must be processed gently to avoid degradation and breakage of the roasted beans. Additionally, freshly roasted beans need to be processed quickly and protected as much as possible from the environment surrounding the conveying machinery to preserve freshness and flavor in the end product.
Ground Coffee & Mixes
Ground coffee is hygroscopic (easily absorbs moisture) in nature and is thus prone to clumping. Additionally, dusting and dust control are of utmost importance when working with ground coffee or coffee mixes due to its combustible properties and for operator environment safety. For ground coffee, maintaining the consistency and size of the coffee grinds is also essential for brewing a good final product.
For coffee mixes, blend integrity can be maintained by using a conveyor that constantly re-mixes the coffee product and prevents separation. Additionally, conveying systems processing different types of flavored mixes or coffees may need to be frequently changed out and quickly and thoroughly cleaned between changes to prevent flavor cross-contamination.
Comparing Totally-Enclosed Coffee Conveyor Options
Flexible Screw Conveyors
Flexible screw conveyors use a spiral or auger inside of an enclosed tube to convey the product up the tube at any angle, including around slight bends. These conveyors are low maintenance and low cost solutions. A flexible screw conveyor is ideal for maintaining continuous blends due to the constant remixixing of the spiral as the product is conveyed. Thus, the flexible screw conveyor may be an option for coffee granules or mixes.
However, the spiral action can be aggressive and may not be the most suitable solution for conveying friable coffee beans. That being said, for some applications, the flexible screw conveyor may still be a good choice due to the unique requirements. Additionally, many manufacturers offer different types of spirals to best suit your applications.
Screw conveyors may also pose limitations when complex layouts with multiple planes are necessary due to the simple linear nature of their design. Thankfully, there are other conveying options that provide more flexibility, discussed below, where layout is a challenge.
Aeromechanical conveyors operate using evenly spaced discs traveling at speed which creates an air stream to convey the coffee along with the discs. Totally-enclosed aeromechanical conveyors are a good option for conveying ground coffee due to their dust-free operation and enclosed design protecting the product from outside moisture.
The aeromechanical conveyors’ stainless steel construction and easy-to-clean features helps to reduce flavor cross-contamination if used for different batches of coffee. The aeromechanical conveyor offers fast and efficient conveying for any product, using relatively minimal horsepower.
However, due to the high speeds at which aeromechanical conveyors do run, there is a risk of product degradation and material breakage for friable whole beans, especially at angles or bend in the conveyor layout. Additionally, the introduction of oxygen or air into a product can cause the product to degrade more quickly. As with any conveying solution, running the coffee product through the conveyor in a test lab to understand the operation and end product condition will be essential.
Read our Excelso Coffee aeromechanical case study: Read case study 1002
Tubular Cable Drag Conveyors: Best Overall
Tubular cable drag conveyors use evenly spaced FDA-accepted polyurethane discs attached to a stainless steel cable to gently drag product along inside an enclosed tube. Cable drag conveyors are quickly becoming the conveyor of choice for coffee processors due to minimization of product degradation being a top priority for whole beans. Cable drag conveyors offer a high throughput of 10s of 1000s of pounds per hour at lower and more steady speeds (vs. the aeromechanical or pneumatic conveying options) which prevents product degradation of friable whole beans. In addition tubular cable drag conveyors are extremely versatile from a layout perspective and can be used to pick-up material from a number of different sources and transport it over long complex routes to a number of different destinations.
Enclosed tubular cable drag conveyors also have the advantage of being hygienic and easy to clean when equipped with clean-in-place dry and wet wash options. Automatic rope tensioning can extend cable life to reduce the risk of downtime and maintenance costs. While these conveyors can represent a significant capital investment, the payback and return on investment can occur very quickly when considering the minimal downtime, ability to run multiple coffee product types on the same machinery and low maintenance requirements.
These factors can make Tubular Drag Conveyors an ideal choice for manufacturers needing to convey both whole bean and ground coffee. Read our Eight O’Clock coffee tubular drag conveyor case study: Read case study 1023
Test, test, test
Finding a conveyor manufacturer that offers test lab facilities is essential for conveyor selection. Our engineers always recommend testing your coffee product to mimic your facility’s conditions and selected equipment before purchasing. Contact Spiroflow’s engineers to set up a materials test for your application.