How about a hot air bean dryer? Difference between hot air bean dryer and semi-hot air semi-direct fire bean dryer

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The traditional semi-hot fan has been popular for many years, which is characterized by heating the drum under the drum and controlling the hot air flow in the drum by the way of throttle, so as to achieve the heating mode of half hot air and half heat conduction.

The shape of the drum-type full-heat fan is basically similar to that of the former, except that the full-heat fan heats the air outside the drum and mixes with the controllable room temperature air before entering the drum to achieve the set baking temperature, and at the same time directly shocks the raw beans with the set temperature, so as to achieve the all-hot air baking method.

Due to the difference of the drum, the semi-hot fan is usually made of smooth solid metal cast iron to achieve the function of heat storage. When the throttle is opened and the heat energy is consumed, the cast iron can store heat to maintain the proper temperature in the drum.

The design consideration of the drum of the total heat fan is not for the purpose of heat storage, because the source of heat energy is supplied by the continuous supply of hot air, and its design focus is on overturning ventilation and distribution.

Compared with the Nordic fire baking method, the difference between the two is that the high temperature of the drum of semi-hot air is easy to cause spots (scald) in the environment of big fire. the reason is that during the dehydration period, there is no time for heat dissipation in the coffee beans and contact with the drum with relatively high temperature at the same time, just like roasting meat over a large fire.

The drum design of the full-heat fan is completely considering how to make the raw beans turn completely, ventilation and distribution do not have much heat storage effect, so the baking temperature conditions set in this environment may be different from the former. This effect forms a long period of flavor development and coffee beans will not coke endogenously in a large fire environment.

The full hot air bean dryer, as its name implies, uses hot air to cook coffee beans, while IMF's Drum is designed to avoid metal heat storage and heat conduction. The source of hot air for baking beans is that the independent burner behind the equipment heats the air flow at 1200 degrees c flame in the combustion chamber designed like incinerator to 550600 degrees (depending on the size of the baking machine and the position of the probe). After being adjusted by Vortex+Equalizer control, the heat flow into the drum is transmitted from high negative pressure to the controllable air temperature and flow rate of the raw bean system to achieve programming and reproduction.

The reason and advantage of the airflow passing through the cylinder from top to bottom-because the height of the cylinder is shorter than the distance from the back to the front, and because no matter how many beans turn over, they will always be thrown down more evenly and more flexibly than when the hot air flow negative pressure leaves the point below.

Since the hot air is heated by an independent fire source outside the drum, which means that the temperature of the drum metal is definitely lower than the air temperature, "the biggest difference between hot air and semi-hot air can be explored and compared from here, and we will skip it here."

As a result, the wind temperature completely controls the rhythm of baking beans, as long as the wind temperature changes the bean temperature will be pulled away, so the design completely avoids the problem of scalding coffee beans. Experienced bean bakers should know that the wind temperature is high and the baking range is short and will not scald the bean table! It's like a dream! Because the characteristic penetration rate of hot air is high and is not affected by metal heat conduction heating, compared with the traditional bean roaster, the bean color is relatively light, but the color of the extracted coffee is indeed darker. The soybean body temperature of high air temperature and high controllable negative pressure is higher than that of caramelized soybean.

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