ABOUT THE COMPANY 
Grain dryers
Another product series of J4 s.r.o. is grain dryers. At present, the company produces the type NS 8000, which is designed for hygienically defect-free drying of products entering the foodstuff market. The NS 8000 dryer capacity is 12.8 m3 and the three-layered jacketed body is 6, 8, 10 and 12 m long.The drying process is continual. The type of drying material should be loose and not sticky such as grain, corn, rapeseed etc.
| Value | Unit | 6000 | 8000 | 10000 | 12000 |
|---|---|---|---|---|---|
| average output (at 4% moisture removal) | Kg / hr | 6000 | 8000 | 10000 | 12000 |
| exchanger output | kW | 300 | 400 | 500 | 600 |
| average natural gas consumption (2 kPa) | m3 / hr | 45 | 60 | 75 | 90 |
| maximum natural gas consumption | m3 / hr | 120 | 120 | 120 | 120 |
| burners – Weishaupt | type | 2 x G3 | 2 x G3 | 2 x G3 | 2 x G3 |
| Chimneys | Pc | 2x | 2x | 2x | 2x |
| heat emitted into dryer surroundings | kW | 30 | 40 | 50 | 60 |
| DN inner diameter of gas piping (2kPa) | mm | 80 | 80 | 80 | 80 |
| built-up area (A x B) | m x m | 2,6 x 10,4 | 2,6 x 12,4 | 2,6 x 14,4 | 2,6 x 16,4 |
| Height | m | 6 | 6 | 6 | 6 |
| Infeed and outfeed (A x B) | m x m | 273 x 273 | 273 x 273 | 273 x 273 | 273 x 273 |
| height of outfeed | m | 1,25 | 1,25 | 1,25 | 1,25 |
| installed electricity | kW | 36 | 36 | 50 | 50 |
| average electricity consumption | kW | 20 | 24 | 32 | 36 |
| compressed air consumption (0,5 MPa) | m3 / hod | 6 | 8 | 10 | 12 |
| grain area volume | m3 | 9,6 | 12,8 | 16,0 | 19,2 |
| chamber volume (inner) | m3 | 25,2 | 33,6 | 42 | 48,4 |
| duration of grain in dryer | min | 40 ÷ 180 | 40 ÷ 180 | 40 ÷ 180 | 40 ÷ 180 |
INDIRECT HEATED GRAIN DRYER NS 8000
Combustion gases of the heating medium are not directly involved in the drying process.
Grain dryer NS 8000 is designed for hygienically defect-free drying of products entering the foodstuff market. The grain dryer has an all-metal three-layer jacketed body, which is enclosed by a machine room from the front fans on the face of the backside. The three-layered jacket is modular and its length (6, 8, 10 and 12 m) directly affects the dryer output. These three jackets define four spaces. The first jacket delineates the heating area in which combustion gases from natural gas circulate. This heating system works under underpressure and is hermetically sealed from the other space – the space between the first and second jackets – which is the space for the heat exchanger, where the waste vapour mixture is heated and distributed to the vent holes of the second jacket. It enters the space of the third jacket here – the space of the dried product. The third jacket is a stainless-steel mesh enabling the outflow of moist air into the surrounding area – thus into the space of the fourth jacket. Drying takes place continually. The output of the dryer is given by the aforementioned type of dryer (body length), the drying temperature and the required percent of moisture removal. The dry product must be a loose and non-sticky material. The dryer is primarily intended for drying grain, corn and rape. The temperature in the dryer heating system ranges according to the type of dried product and the size of the temperature gradient from 160 to 360 °C. This temperature ensures the transfer of heat into the second space where the waste vapour is heated and the vent holes entering the active space. This drying temperature once again depends on the type of dried product and the temperature gradient of the exchanger. It ranges from 40 to 120°C. NS 8000 dryer capacity if 12.3 m3. The dryer is equipped with an upper feeding screw, which fills the dryer and refills the decreasing dry product. The product drops via the third space, in the right and left strand, which completely surround the source of heat. The drying air mixture causes the product to fly around and then gravitate slowly to the intercepting flaps in the bottom part of the dryer. The flaps gradually, in regular intervals, empty the product into the lower unloading screw, which then continually moves the product to the conveyor passage and all the way to the bunker. The dryer’s operation is controlled by a programmable automatic device. Here we select the temperature, the drying period and thus directly influence the dryer’s performance. The dryer’s operational safety is ensured by a doubled security system. Control of the combustion process is in compliance with European standards. The filling opening’s dimensions are 273 x 273 mm and it is positioned at the height of 6150 mm. The unloading opening has the same dimensions and is positioned at 1250 mm. The hold-up duration for the product in the dryer is optional from 40 minutes up to three hours. The dryer’s ground plan takes up 2.6 x 12.45 m and the required free surrounding space for manipulation must be a minimum of 1.5 m. The dryer burdens the surroundings with natural gas combustion (max. 1400 m3/hr. – combustion in the Weishaupt G3 burner with decreased NOx). The leaving velocity from the chimneys does not exceed 3.5 m/s. Furthermore, the surroundings are loaded with water vapour in the amount of ca. 500 kg/hr, which the dryer extracts from the dry product. The leaving velocity from the slots of the outer jacketing does not exceed 0.04 m/s. The noise level does not exceed 85 dB at the attendance site. The dryer is not a source of vibrations. With regards to energy, the dryer demands a max. of 120 m3/hr of natural gas (2 kPa), 36 kW of electricity. To control the flaps, 0.5 MPa – 5m3/hr of compressed air is necessary. The entire dryer operates in a very economical energy regime given by its construction, as the source of heat is completely surrounded by the product being dried. In this case, the transport of heat from the source to the exchanger is zero. All sources of heat with the exception of chimney losses must go through the dried product. Chimney loss (ca. 25%) is an inevitable tax for the hygienic “correctness” of the indirect NS 8000 type dryer.