Germany
To prevent conflicts with neighboring shops and meet the requirements of regulatory authorities, Probat shop roasters can now be fitted with a system for exhaust air treatment.
"Due to their location in pedestrian or downtown areas, specialty roasters often need to meet certain exhaust air requirements," according to Daniel Schmidt, manager, shop roaster sales at Probat. "Numerous queries and conversations with customers confirmed how urgent this issue is for owners of specialty roasting shops."
The system is available for the shop roasters Probatone 5, 12 and 25. It effectively filters particles such as coarse substances, dusts and oils from the exhaust air stream. It was developed by Probat and tested by Einstein Kaffee in Berlin. The new exhaust air treatment can reduce undesired odors created during roasting by up to 75%. This takes place by cleaning the exhaust air by means of zeolite granulate.
During the research and development phase, cassettes consisting of zeolite granulate proved to be the best solution. Certain kinds of zeolite, a complex mineral, effectively absorb odors. After special processing, they are thus ideal for exhaust air treatment of shop roasters.
"Both the investment and maintenance costs of the system are a lot lower than the operation of an afterburner, a washer, or a catalytic converter," explained Thomas Koziorowski, head of R&D at Probat. "Because the technology works without a burner, no additional energy input is required. Moreover, the extracting process for the zeolite is environmentally-friendly."
Used zeolite granulate can be disposed of in normal household waste. Customers can get refill granulate or replacement cassettes directly from Probat.
The company evaluated several different technologies and implemented key objectives in the development phase. Besides a significant reduction of undesired odors and low operating costs, the system is easy to service and safe to operate. Cleaning requirements are displayed via an integrated pressure gauge. Cleaning is also easy: the filter pad for coarse particles located upstream to the zeolite cassettes can be cleaned with a vacuum cleaner.
Long change intervals were important as well: Depending on individual factors, one zeolite filling allows roasting of about 8,000 kg of coffee. Depending on roaster batch sizes (5, 12 or 25 kg) different zeolite quantities (16, 32 or 64 kg) are required. Moreover, due to its compact design, the system can be easily integrated in existing shops without wasting space.
The exhaust air treatment system is directly fitted to the Probatone shop roaster’s cyclone. The roast exhaust air is ducted into the system, initially moving through the pads, which filter out the remaining coarse particles. It then streams through the zeolite cassettes, which absorb most of the odors due to their chemical properties. The cleansed exhaust air is then ducted out the conventional way. Numerous trial roastings in their own R&D department as well as in a long-term test on a customer’s premises produced a broad data basis. Olfactory tests were carried out by the German technical inspection company TÜV and evaluated by Probat. Results showed that, depending on influencing variables such as coffee type, degree of roasting and roasting time, the system reduces odors in roast exhaust air by up to 75%.
