Heat pump dryer currently on the market is mainly divided into two types: integrated machine and split machine. The integrated machine comes with a relatively small drying room, while the split machine builds a thermal insulation drying room according to the type and quantity of drying materials. , can be large or small and more flexible. The split type heat pump dryer is widely used in the market. When the split type heat pump dryer builds a drying room, it needs to determine the size and size of the drying room according to the quantity, volume, material properties and air duct design. Avoid waste of drying room, excessive loss of heat and decline of drying quality.
The quantity of materials to be dried is the most important factor affecting the size of the drying room. When building a drying room, the size of the drying room needs to be determined according to the drying requirements of the customer. For example, the material that the customer needs to dry is figs, and the daily processing of fresh fruits is 1200-1500kg. First, according to actual experience or temporary calculation (spreading figs on the material tray), determine the spreading density of figs, usually 5kg/㎡ (different materials have different spreading densities); secondly, according to the material rack and material tray The quantity and size of the pallets determine the actual material placement area. For example, the designed trolley has 15 floors, and the area of each floor is 16-20㎡, then the total area of the pallet is 240-300㎡, that is to say, the clearance area of our warehouse It needs to be more than 20㎡.
With the above data, we can calculate the size of our drying room according to the equipment we use. It should be noted that a certain gap needs to be left between the material rack and the surrounding walls of the drying room, and a gap should also be left between the material rack and the material rack to facilitate the entry and exit of the staff. In addition, generally, a 300mm reserved area should be added at the air outlet and return air outlet, plus the space required for installing the main unit (the main unit of the open system is placed outside the drying room, so there is no need to consider the space occupied by the main unit). Get the size of the drying room.
The air duct structure adapted to the material also has a certain impact on the design of the drying room. According to the properties of the material itself, when designing, it is first necessary to judge whether the material to be dried is suitable for the advection air duct or the through-flow air duct. The advection air duct considers the convenience of loading materials, the height of the material cart is generally 1700mm, and the height reserved at the top is about 300mm, so the actual inner height is 2000mm, and the inner height of the drying room can be adjusted appropriately according to the structure and height of the main machine. In principle, Satisfy the operator not to be too depressed after entering.
The shape of the material is also an important factor affecting the design of the heat pum dryer's drying room. Generally speaking, the larger the volume, the larger the space it occupies, requiring a corresponding increase in the size of the drying room. For example, flowers and tea cakes, flowers are large in size and small in weight, while tea cakes are heavy in weight and relatively small in size. Under the same weight, the area of drying room required for tea cakes will be much smaller. For example, to dry 2000 catties of flowers at a time, it is generally necessary to build a flower drying room with a size of 8.5×2.8×2.2 meters, but the same weight Tea cakes only need half the size of the drying room.
So, is it true that the larger the volume of the material, the larger the size of the drying room that needs to be built, and the smaller the size of the drying room that needs to be built? In fact, it is not necessarily true, because the material itself generally has density, moisture content , heat capacity, etc., so the water outlet speed of different materials is different. For example, walnuts, pine nuts and other nut materials have small water content, low drying rate, long drying time, and are not easy to deteriorate. Therefore, when placing materials, they can be stacked. The dry quantity will be greatly increased; and fresh meat, aquatic products, fruits and other materials, due to their high water content, the water outlet speed is also high, but such materials are in a high-temperature drying environment, if the humidity in the drying room is too high, It will cause the material to deteriorate, so when setting up the drying room, it is necessary to increase the area of the drying room and reduce the amount of material to be dried.
According to the shape (volume) of the material, the thickness of the single-layer material stacking is determined. The thickness of the single-layer material stacking plus the layer spacing (usually 50-80mm) is the height of the single-layer space. With the height of the single-layer space, according to the layer of the material rack The required height of the drying room can be calculated. For example, if the thickness of a single layer is 10mm, then the height of the single layer space is 60-90mm. The height of the drying room is 1980-2820mm, and the length and width are determined according to the number of material racks and the length and width of a single material rack.
Heat pump dryer is a complex system engineering. There are many factors to be considered in the design. It must be designed according to the quantity, volume, properties of materials, performance of heat pump dryer, air duct design and other factors. Because of the lack of construction standards, the principle, there can be a certain space for free control, such as reserved space, interval, material rack size, etc., but it should not deviate too far, otherwise it will affect the energy saving of the system and the drying quality of materials.
