Roasters Rock: Planning for a Plant Upgrade

Roasters Rock Monthly Column

(Fixing what you did not plan for in the beginning)

Remember when the company just started? Everyone was motivated, passionate and the future was exciting. Remember that business plan? It was really conservative because you had no idea how many pounds per week you were going to roast. Capacity to roast was not a thought because you were starting at around 0% and that left 100% unknown. 

A common mistake / oversight that new roasting businesses make is understanding ALL of the components that go into capacity building. At best, a forward looking business plan calls for leaving a space next to the first roaster to add a second roaster. Double capacity possible! Except it doesn’t really work that way. Now you have to figure out where to put the ‘other stuff’ that comes along with growing capacity.  

We will explore Green Handling, Roasting, Roast Coffee Handling, Packaging, Finished Product (and Allied Product) Storage.  This article does not explore coffee ’conversion’ such as creating extracts or Ready to Drink products as that is a whole article in itself. 

Capacity is interesting because it creates the question of defining Small, Medium and Large roasting plants. For the purpose of this article we will use pounds per week as our measurement.  

Small = 1- 4000 pounds/wk or up to about 200,000/yr  

Medium = 4001- 20,000/wk or up to about 1,000,000/yr 

Large = 20,001 + /wk 

If you are roasting 100 pounds per week, 4000 might seem large! But even so, you need to imagine your company getting to that 4001 range. If you plan now it won’t be a surprise. 

Green Handling 

The small roaster is likely getting a lot of single varietal, higher end coffees. As they grow they move to booking out pallets of coffee that make blend components. At this stage you are buying fairly clean coffee and will likely not have anything but a hand truck, pallet jack and some dunnage racks that will keep single bags up off the ground. Shipments come bi-weekly so storage is not a huge amount of space. 

The medium size roaster is now having to buy a lower grade of coffee in order to watch margins on blends as well as have a consistent supply all year round. This takes us to the need for green cleaning, dust collection, conveyance and silos. This requires air compressors and vacuum systems to run. The plant ceiling height now needs to be about 18’ so the silos can fit and you can start stacking pallets and/or forklifting pallets onto racks. A 3 month on hand supply can take a lot of space and there is usually a loading dock dedicated to receiving green. Green conveyance moves past the hand truck and to an automated system of either pneumatics or a tube conveyance. The discharge from silos will require a weighing system for preparing batches to be roasted. 

The large roaster looks like a medium roaster but with a different scale and probably has a portion of the warehouse dedicated to green handling, including an ability to fumigate for moths. This area will likely be temperature and humidity controlled and may have to store a 6 month supply of coffee. It is not uncommon to add a green destoning system to clean the foreign matter. The silo system will likely be computerized and integrated into the overall plant operating software control system. 

Roasting 

A roasting system has a few standard components; Loader, roaster, destoner, and smoke abatement. 

The small roaster uses a floor scale, bucket and muscle for loading. The roaster likely has 12 kilo or less capacity per batch. A destoner is often not purchased and roasted coffee is conveyed away by bucket or rolling bin. Smoke abatement is either not required or is done via an electrostatic device or small thermal afterburner. 

The medium roaster may have a loader right next to the machine and manually feed the green coffee into it or they might have silos discharge to the loader. Roasters are 140 Kilos or less. There is likely more than one roaster which compounds the system requirements for conveyance etc. The destoner discharges into a conveyance system. The afterburner is likely a heavily regulated device and will need to meet strict requirements. A Catalytic Oxidizer is good for this. 

For large roasters, manual loading is a distant memory. All coffee is cleaned and stored in silos prior to roasting. The roasters are about 280 kilo and there will be more than two or three with room for more. Destoners are on every machine, and the afterburners will put out nothing but hot air.  

Roast Coffee Handling, Storage and Allied Products 

This part of plant design gets tricky as there are many ways to grind and package coffee.  

A Small roaster has a deli scale, a bucket and a scoop. Grinding is done by ‘shop’ grinders with about a 3lb / min capacity. Coffee is rarely degassed as it is being put into bags with one way valves. A manually operated floor sealer is used to seal the final product. 

Medium roasters now have to have conveyance systems, roller grinders, and silos for degassing. Packaging will be automated and they likely have one machine that does several types of packaging. This is when nitrogen generation onsite should also be considered. 

Most large companies will have multiple packaging lines thereby multiplying the space requirements. Some machines can do multiple types of packaging but ultimately you have to be able to package as fast as you can roast so multiple lines are needed to avoid bottlenecks. 

In talking with larger companies, the place where they say they underestimated capacity was at the outbound delivery dock. They ran out of room to store products because they only planned for coffee and forgot syrups, straws etc. They also underestimated to the number of docks needed at one time to load trucks. 

So when you are imagining your growth in your business plan, don’t stop at roasting capacity! The rest of your plant has to support the volume as well. 

Rocky Rhodes is an 18 year coffee veteran, roaster, and Q-Grader Instructor, and his mission now is to transform the coffee supply chain and make sweeping differences in the lives of those that produce the green coffee. Rocky can be reached at [email protected]

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