*1. Nominal working condition: outdoor side: dry bulb temperature 20℃, wet bulb temperature 15℃;  Indoor side: dry bulb temperature: 70℃, wet bulb temperature:

*2. The moisture discharge capacity is calibrated under standard test conditions and will be different due to indoor and outdoor wet bulb temperature changes.

*3. Models, parameters and performance may change due to product improvement without prior notice. Specific parameters shall be subject to the nameplate of the product.

Working principle of direct heating grain dryer (combined with drying tower)

It adopts mixed-flow drying process, and the cleaned grains are fed into the dryer by a hoist. The grains flow continuously from top to bottom of the equipment by their own weight, and the tempering and drying process are realized during this flow process.

The hot air can flows in the same or opposite direction of the grain, which is called mixed flow. By adjusting the temperature of the heat pump dryer, when the hot air passes through the grain layer, it transfers heat and moisture with the grain. This means the hot air transfers the heat to grains, and the grain increase their temperature naturally. When the grains are heated, the water evaporates into the air and becomes exhaust gas. Reasonably matching the air volume of the induced draft fan to realize various drying temperatures and to control the ratio of air volume to grain. By adjusting the speed of the grain discharge motor, the residence time of the grains in the drying section is controlled, and the dried hot grain flows down to the tempering section. The temperature and moisture content of the inner and outer layers of the grains tend to be balanced after the tempering stage, therefore, it not only achieves moisture uniformity of the whole batch of grains, but also achieves the purpose of high-quality, high-efficiency, and energy-saving drying.

Schematic diagram of the working principle of direct heating grain drying equipment

Machine components:

1、Heat pump drying mainframe：it mainly used for connecting the drying tower, the heat source is to absorb the air and then use it for compression, and then generate gas with high temperature and high pressure.

2、Drying tower：Grain dryer equipment is divided into heat source and drying tower, the drying tower transports our grain to the drying area, and then drying along with the belt and flow down. After the drying is completed, it will enter into grain discharge area for discharge

Drying process

In the pet feed production process, drying is a very important link. The pet feed production process is as follows:

Raw material configuration-mixing and stirring-extrusion molding-drying-oil spray (seasoning)-weighing and packaging.

The pet snack drying box can set different drying processes according to the customer’s drying requirements. The control system adopts a touch-screen control mode, which can set multiple time periods (up to 10 time periods), different temperatures, and drying room humidity to drying the materials. The equipment has its own refrigeration function. The dried fruit needs to regain moisture after drying. The refrigeration mode can be set, and the mainframe can automatically complete the conversion between the heating mode and refrigeration modes. In addition, it has storage memory function for drying process.

The pet snack drying box adopts PLC & touching screen programmable control system, which can accurately control various curve parameters in the drying process. The temperature and humidity control accuracy is high. The humanized touch screen can operate delicately and automatically, which can realize intelligent management. There is no need to manually turn over animal materials, no need to change baking trays and carts, and no need for special personnel on duty,  thus it saves lots of effort. The dried product is of high grade, and the machine is simple and convenient to operate, which does not require full-time technicians to operate the equipment. The drying temperature is mild, so there is no need to worry about the high temperature in the air outlet area will affect the quality of the air outlet products.

Machine Components:

1.Rear air supply integrated machine: controls the start and stop of the drying room; controls the temperature, humidity, and dehumidification time of the drying room; provides heat energy for material drying.

2.Polyurethane sandwich board warehouse provides heat preservation for drying room materials.

3.Fan wall: Provides wind energy for the drying room materials to bring out the moisture in the materials; brings out the heat energy in the host to make the drying room heat up or cool down.

4.Air guide wall: guides the wind of the fan wall to the front end, so that the air volume before and after the drying room is consistent, and achieves the purpose of uniform drying of materials.

*1. Nominal working condition: outdoor side: dry bulb temperature 20℃, wet bulb temperature 15℃;  Indoor side: dry bulb temperature: 70℃, wet bulb temperature:

*2. The moisture discharge capacity is calibrated under standard test conditions and will be different due to indoor and outdoor wet bulb temperature changes.

*3. Models, parameters and performance may change due to product improvement without prior notice. Specific parameters shall be subject to the nameplate of the product.

Working principle of direct heating coffee bean dryer (combined with drying tower)

It adopts mixed-flow drying process, and the cleaned coffee beans are fed into the dryer by a hoist. The coffee beans flow continuously from top to bottom of the equipment by their own weight, and the tempering and drying process are realized during this flow process.

The hot air can flows in the same or opposite direction of the coffee beans, which is called mixed flow. By adjusting the temperature of the heat pump dryer, when the hot air passes through the coffee beans’ layer, it transfers heat and moisture with the coffee beans. This means the hot air transfers the heat to coffee beans, and the coffee beans increase their temperature naturally. When the coffee beans are heated, the water evaporates into the air and becomes exhaust gas. Reasonably matching the air volume of the induced draft fan can realize various drying temperatures and can control the ratio of air volume to coffee beans. By adjusting the speed of the discharge motor of coffee beans, the residence time of the coffee beans in the drying section is controlled, and the dried and hot coffee beans flows down to the tempering section. The temperature and moisture content of the inner and outer layers of the coffee beans tend to be balanced after the tempering stage, therefore, it not only achieves moisture uniformity of the whole batch of coffee beans, but also achieves the purpose of high-quality, high-efficiency, and energy-saving drying.

Schematic diagram of working principle of direct heating coffee bean drying equipment

Machine components:

1、Heat pump drying mainframe：it mainly used for connecting the drying tower, the heat source is to absorb the air and then use it for compression, and then generate gas with high temperature and high pressure.

2、Drying tower：Grain dryer equipment is divided into heat source and drying tower, the drying tower transports our grain to the drying area, and then drying along with the belt and flow down. After the drying is completed, it will enter into grain discharge area for discharge

Coffee bean heat pump drying system (box type)

Engineering installation is industrial standardization, and the integrated design is no longer need to implement drying room installation. It is plug in and play and installed with an AI artificial intelligence control. It could fully retain the nutrient composition, color, aroma, taste and shape of materials after drying, in addition, it could realize Multi-level energy efficiency and comprehensive heat utilization, which saves more than 70% of energy than traditional methods. The characteristics of Shuntec drying equipment include: (1) negative pressure air distribution, which is patented;(2) uniform drying without dead corner, which could realize drying uniformity of the whole batch; (3) intelligent management; (4) recording the drying process intelligently; (5) real-time monitoring; (6) unattended.

Working principle diagram

Coffee bean drying process

Drying

The moisture in the coffee beans shall be evaporated. When the coffee beans begin to absorbs heat, the color of the coffee beans changes from green to yellow or light brown. After the silver film falls off, the faint grass aroma will spread to the surroundings. This process takes almost half of the entire roasting time. Although it only removes the moisture in the coffee beans, the evaporation rate control is the key element. Generally, it takes about ten minutes for the water to reach the boiling point, and then the moisture in the roasted coffee beans begins to evaporate until all of it has totally been evaporated.

Pyrolysis (twice)

When the moisture of the coffee beans begins to evaporate into gas, the first popping sound will occur, then it turns to heat absorption process. At this time, the internal pressure of the coffee beans can reach 25 bar. Under strong pressure, coffee beans begin to deconstruct the original organization, generating the flavor and taste. When the temperature reaches 190 degrees, the endothermic and exothermic transition occurs again. Under the action of pyrolysis, the color of coffee beans also began to change, gradually turning from brown to dark brown, and at this time began to re-roast.

cool down

After the coffee is roasted, it must be cooled in time to stop the pyrolysis effect, so as to lock the flavor and prevent the flavor from losing. There are two cooling methods, one is air cooling and the other is water cooling. Air-cooling uses a lot of cold air to cool the coffee in three to five minutes. Compared with the air-cooling type, the water-cooling type is slower, but it is clean and unpolluted, and can better retain the aroma of the coffee, but the control of the water mist must be calculated accurately timely.

Precautions for roasting green coffee beans

Achieving the highest caramelization

Caramelization is an important factor that affects the flavor of coffee. As green beans absorb a lot of heat energy when roasting, the first crackling sound occurs at this time. At this time, sugar begins to be converted into carbon dioxide, water continues to evaporate, and the aroma of coffee will gradually radiate out and form coffee grease. This pyrolysis reaction can continue to the second explosion, but when the second explosion is completed, coffee bean’s temperature should be lowered with cold air as soon as possible, so that the highest caramelization can be achieved.

Minimal carbonization

During the baking process, some ingredients will also be carbonized, forming a bad bitter substance. Therefore, when the second burst is completed, the heating can be stopped to minimize the carbonization at the same time.

Pay attention to the voice change

Coffee beans will make two popping noises during the roasting process. The first popping sound is low, indicating that starch begins to turn into caramel, and water evaporates with carbon dioxide. The second popping sound is more violent and sharp, which is the fibers breaking voice of coffee bean cell . At this time, you should stop heating immediately and use cold air to lower the temperature as soon as possible. The interval between the first bursting time and the second bursting time can be quite long. Therefore, when baking different beans, you must find the best baking conditions for the beans.

Pay attention to changes in color and taste

The color of the coffee beans will change from green to light brown as the temperature continues to rise, and then become a reddish brown with a trace of oil, afterwards, it will turn into a shiny dark brown with a large amount of oil. At this time, you should not need to bake it anymore, otherwise the coffee oil on the surface of the beans will become dried, and a lot of smoke and burnt smell will be emitted.