Longan (longan dry) baking process: initial baking. Longan over rock, placed on baking rack, promoting Curing Barn. The first to use high-temperature baking baking temperature control in more than 70 ℃, bake for 6 to 8 hours, the medium-term temperature control in 60 ℃ ~ 70 ℃, the entire baking time in about thirty hours or so, until the barn Nutshell harden. Bake again. First baked dry longan 1-2 days after placement, stone, flesh internal moisture gradually spread outward, pulp surface more humid than immediately after baking, must be re-baking. At this early may be baked into the size of longan fruit two levels, namely baking. Then baking the same methods and early baking temperature control in about 60 ℃, the baking time is about 4-6 hours. General longan after baking to the stems with your fingers and then gently push it to fall off. At this point, the flesh showing fine wrinkles, dark brown, the surface is dry, press with your fingers no juice flowing, biting pit easily split, the section was gray vegetation, drying is moderate, generally drying rate of 33-36%. Drying standards and quality requirements. Drying standard: Nutshell hand soft reduction can level off, the flesh dry russet, shiny, wrinkles, stone biting easy to crack, the section was gray vegetation. Quality requirements: same grade longan to dry evenly, stem end intact, a sleek, no flesh burning smell, no mildew, no insects, broken shells of not more than 5%. Principle longan (longan) heat pump dryer: acting through the compressor, the driving pipe heat transfer working fluid to absorb heat in ambient air, and then release heat through the heat exchanger means to the drying room by circulating hot air system for continuous drying process. Structure longan (longan) dryer: 1, a heat pump dryer heating dehumidification unit. 2, insulation box member. 3, hot air circulation unit. 4. Situation intelligent control unit longan (longan) Drying 1, a large multi-use electric heating barn factories, power consumption, and high cost. 2, electric heating temperature is high, uneven heating, prone to deformation and stratification unglued. It can cause severe burned or fire. 3, the heating device life is short, frequent maintenance and replacement. 4, part of the plant using steam dryer, not control the temperature, leading to product quality problems drying. 5, small-scale plants to use more natural sun-dried or air-dried approach. Long production cycle, low efficiency, greatly affected by the weather, not continuous production, high labor intensity, drying quality is difficult to control. Our solution to the problem: 1, using a heat pump for longan (longan) for drying, low energy consumption and drying process, reduce operating costs. 2, the drying process is good ventilation, heat evenly. 3, the control parameters corresponding chrysanthemum dried, the drying process can effectively solve the problems. 4, safe and reliable drying process, the drying process without the risk of overheating or combustion. 5, temperature and humidity control, high accuracy. Effectively avoid the manual operation which led to excessive drying or drying quit phenomenon, reduce labor intensity and reduce operating costs. Heat pump dryer using heat pump drying unit place for hotels drying bedding, seafood, vegetable dehydration, AD black fungus, melon seeds, peanuts, fruits and vegetables, meat, sausage, tobacco, leather, mushrooms, wolfberry, dried fruit, mosquito coils, tribute incense, cloth, clothing, food grains, noodles, dried bean, fertilizers, pharmaceuticals, medicines, paper, wood, seeds, sludge, gypsum, metal products, metallurgical products, mining products, chemical products , dry flue gas desulfurization gypsum, clay, grass, tobacco, pulverized coal, coal, lignite, etc.