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Sunday 16 September 2012

Updated Hot Air Blower - Canadian Coffee & Tea Show

The High Pressure Hot Air Blower was updated for the Canadian Coffee & Tea Show in Toronto.  The new Insulation package improved the heat retention and made the unit even quieter.  The improved insulation is directly influenced by the desire to improve the conditions in the Roastery.  The direct participation of Roastaire supervisors meant that most of that effort would be directed to reducing both the heat and sound emissions.

Before insulating the Blower we installed improved flexible inlet and outlet connectors to decouple the rotating components from the static parts that could act as "loud speakers".  Again the moving parts were balanced to a high standard, better than G2.5, to "nip the noise source in the bud".  The new flexible connector is less transmissive and has the added advantage of having a smoother and less restrictive bore.

The deadline of the Canadian Coffee & Tea Show meant that there was no time for picture taking.  The fact that we were able to have a "normal" conversation in front of the working blower attests to the effectiveness of the sound containment.  After all, to achieve blower pressures it does have to turn at high speeds.

Containing the heat improves the efficiency of the roaster, reduces the temperature of the other components, and keeps the Roastery cooler.  The Roastaire components are insulated and mostly double walled, unlike most roasters, which greatly enhances the roasting experience.

This does bring about a philosophical design difference with bare bones roaster manufacturers that are promoting low entry prices.  Some show attendees quoted roaster prices that were much lower but the manufacturer omitted to tell the interested parties that an After-burner would be required for roasting in their city and that the After-burner would cost much more than the roaster to buy and to operate.  Neither the coffee nor the client should be "burnt".

The Impeller was also redesigned to improve efficiency and reduce noise generation.  The Impeller must redirect air that is moving axially to a radial flow as gradually and smoothly as possible.  Of course machining a steel Impeller to accomplish this requires many hours in a CNC Mill but if the noise is minimized and the output maximized at the source then the task is easier later on.  Aluminum is certainly cheaper to machine but our small pile of stretched, torn, distorted, and exploded off the shelf aluminum Impellers that could not handle our heat requirements attests to the need of using a steel Impeller at elevated temperatures.

After 1500 hrs Aluminum Rotor self destructs at 250°C


Another Aluminum Rotor tears at 250°C



The picture below was taken before the show opened. More picture are located here.  During the show there were too many interested people to get a clear shot of the roaster.  It was, after all, the only working roaster at the Canadian Coffee & Tea Show in Toronto. 



Wednesday 12 September 2012

The Roastaire™ visits Canadian Coffee & Tea Show

The Roastaire™ was the only functioning coffee roaster at the Canadian Coffee & Tea Show in Toronto.


The booth was near the Canadian Barista Championships but we were so busy that it was impossible to attend the skill demonstrations.

The Roastaire™ booth was designed to emulate the look of a Roastaire, coffee roaster, in a roastery café.  This layout favours the Theatre of Roasting which invites clients to observe the roasting process.  The clientele is able to pose questions to the Roastmaster without having the liability of having someone brush against hot surfaces.



 
The "roast is arrested" in the Roasting Chamber within seconds then is pneumatically conveyed to the Packaging Area where the beans are cooled for an additional three minutes while the Roastaire™ roasts another batch of beans.

In the picture below Mel, the Roastmaster, is removing the roasted beans from the Cooling Hopper (usually located in the packaging area).  The beans are cooled while another batch is roasting.  Many people dropped in to view the only functioning Coffee Roaster at the Coffee & Tea Show.



So very close now to a Freshly Roasted cup of coffee.

 The tiff to jpg conversion is off which emulates working before enjoying a Freshly Roasted cup of coffee.


After a Freshly Roasted cup of coffee everything just works better.   Even technology is receptive!

Friday 7 September 2012

The Canadian Coffee & Tea Show

Well we are on our way to The Canadian Coffee & Tea Show in Toronto.


The trailer was packed with the Roastaire and the booth earlier in the week.  We expect to be roasting 3 kg batches in the conference hall without a chimney.  We did this at two earlier Canadian Coffee & Tea Shows in Toronto and Vancouver therefore it is not a new experience.  No other roaster appears to have the pollution controls to attempt this.

It will be a rather hectic event with many seminars, presentations, and discussions therefore there will most likely only be a recap after the show.  Perhaps Roastaire will be updating their blog during the event .