Coffee Roasting Exhaust Systems
How are coffee beans roasted? What equipment is needed for roasting coffee beans?
Commercial coffee roasters first drop raw coffee beans into loaders, which feed into a rotating drum. The drum is pre-heated to a temperature of around 450 degrees F. After 12-15 minutes, depending on the type of roast, the roasted coffee beans exit the drum at temperatures around 350F degrees and are placed on a cooling tray at the front of the roaster. A special machine removes any stones or debris before someone manually checks for defects. Once cooled completely, the roasted coffee beans are finally packaged for sale. So, we can see that there are really three stages to the process where exhaust and particulate extraction is needed, where ducting is needed.
- The loading stage. When the beans are loaded into loaders and drums, dust can bloom. Hoods and ducting can be used to capture the dust and prevent it from settling back into the drum.
- The initial roasting stage. Heat from the drum, bean hulls/skins, and dust all need to be extracted as exhaust from the 450F degree drum environment.
- The cooling stage. As the coffee beans move from the roaster to the cooling tray, both particulates generated during roasting and heat from the drum need to be collected and conveyed through ductwork as exhaust or to a collector for filtering prior to exhaust.
Because types of ductwork needed for these applications varies, it is important to have a coffee roasting duct system that provides the right combination of versatility, seal and heat tolerance. NOTE: Please consult your authorities having local jurisdiction regarding "clearance to combustibles" and other code requirements. When ducting is traveling through a building envelope, or near combustibles, single wall ducting may need modifications (shielding or double wall segments).
Types of ducting used for roasting coffee
US Duct offers two clamp together ducting options for coffee roasting: Clamp Together Duct (also called rolled-lip duct) and US Tubing (an air-tight clamp together option). Clamp Together duct offers a number of benefits:
- Ease of installation
- Variety of metals, gaskets and components
- Ease of disassembly and reassembly for cleaning and maintenance
Benefits of using clamp together, rolled-lip duct for coffee roasting
US Duct’s Rolled-Lip Clamp Together System utilizes a rolled edge that is formed on the ends of all parts. The lips are joined together with an over-center clamp containing a sealing gasket. The clamp pulls the ends together and envelopes them inside the sealing gasket. This clamp together system provides a fast install time (70% faster than flange connected ducting) and ease of adjustment. The pipe can be easily disassembled and reassembled for easy cleaning and maintenance. This system is ideal in coffee roasting ducting for the dust and nuance particulate collection required for many coffee roasting applications.
Download Rolled Lip Clamp Together Ducting Specifications
US Tubing as an option for coffee roasting vent systems
US Tubing, US Duct’s airtight clamp together system, is guaranteed to be leak-free in both positive and negative pressure applications. Each component terminates in a flat, turned-out lip. A v-shaped gasket fits over the one lip on each joint and then the connection is joined by a stainless-steel, adjustable clamp. When the clamp is tightened, if compresses the ends and gasket to form The Ultimate Seal®. This clamp together system provides a fast install time (50% faster than flange connected ducting) and ease of adjustment. The pipe can be easily disassembled and reassembled for easy cleaning and maintenance. The tighter seal of the US Tubing system is ideal for coffee roasting ducting systems where no leaks are acceptable.
Download US Tubing Clamp Together Ducting Specifications
Additional duct products that complete your coffee roasting exhaust system: