Single layer circulation through flow belt automatic dryer

The single-layer belt mounted continuous drying line is composed of DWP cross flow circulating belt dryer (invention patent No.: 201110059169.0) developed by our company in series. Each production line is composed of several drying units and a cooling unit. Each drying unit section includes circulating fan, heating device, fresh air supplement system, and public tail gas emission system and tail gas reuse system. The process flow is as follows: after the materials come out of the previous process, they are poured into the upper hopper of the feeding table, homogenized by the homogenizing device, and then brought into the dryer by the conveying mesh belt, and the running speed of the mesh belt is adjustable; The cold air enters the centrifugal fan from the fresh air make-up port. After being heated by the fin heat exchanger, it enters the dryer and passes through the material layer through the speed-up of the special structure for full contact with the wet material for heat and mass exchange. The water in the material is evaporated into water vapor and taken away with the hot air. Part of the wet air is emptied from the wet exhaust port and the other part is recycled; Due to the different moisture content of materials in each unit, the proportion of moisture discharge and circulating air in each unit is also different; In the whole drying process, the hot air humidity is also different; At the initial stage of drying, the moisture content of the material is high, and a higher hot air temperature can be selected; In the later stage of drying, the moisture content of the material is low, so a lower hot air temperature can be selected to greatly improve the drying efficiency.

Capacity compatibility table (taking Spiced melon seeds as an example, the formula does not contain white sugar, brown sugar, etc.)

characteristic:

1. The air volume, heating temperature, material residence time and feeding speed can be adjusted to achieve better drying effect, and the equipment configuration is flexible;

2. Mesh belt flushing system and material cooling system can be used;

3. Heat recycling to save energy;

4. The unique uniform air device makes the hot air distribution more uniform and the drying intensity higher, so as to ensure the consistency of product quality and fast drying;

5. The heat source can be steam, heat transfer oil, electric or hot blast stove (the fuel can be biofuel, natural gas, alcohol based fuel, diesel, etc.);

Supporting heat source

The heat source of the machine can adopt natural gas or liquefied petroleum gas hot blast stove, heat transfer oil and other heating methods.

If natural gas or liquefied petroleum gas hot blast stove is used for heating, the hot blast stove adopts advanced high-efficiency and energy-saving burner with full-automatic proportional regulation operation. The burner meets the requirements of relevant standards for reducing pollution and emission, has passed the IP x0d (IP40) standard electrical protection level certification, and has passed the en 676 gas appliance European standard, EMC low voltage and boiler efficiency certification.

According to different environmental protection in different places, imported combustion engines meeting the emission standards of local environmental protection requirements shall be adopted, and the steady-state emission NOx of the hot blast stove of the machine shall not be higher than the rated emission value of the combustion engine, and the steady-state emission value D of CO (O2) shall be within the national standard; CH4 steady state emission value: 0ppm; The machine adopts a single proportional adjustment high-power combustor and an external hot blast stove for independent heating, which reduces the fault points, maintenance time and maintenance cost. At the same time, the external hot blast stove is separated from the dryer host, which improves the uniformity of hot blast, avoids the dust entrained in the circulating hot blast in the baking process from contacting with the high-temperature combustion area, and effectively prevents potential safety hazards.

The hot air passes through the air inlet duct to the electric damper of each drying room. Through digital accurate adjustment, the baking is more uniform, the product quality is higher and the taste is better.

If heat transfer oil is used for heating, each drying unit is equipped with a set of heat exchange system and control system. The control system uses advanced pneumatic proportional control valve combined with PID intelligent temperature control system to accurately control the drying temperature. According to the drying and baking process of different materials, the air inlet, moisture exhaust and circulating air volume are adjusted through PLC program controller and the required drying and baking parameters to achieve better drying and baking effect and achieve energy saving and consumption reduction.