Microwave vacuum drier

Abstract

The invention discloses a microwave vacuum drier, which comprises a feeding vacuum chamber, a microwave vacuum chamber and a cooling discharging vacuum chamber, which are sequentially connected through vacuum valves. A stepping conveyor is arranged in each vacuum chamber, the vacuum valves are arranged at the front end of the feeding vacuum chamber and the rear end of the cooling discharging vacuum chamber respectively, and a microwave heating device is arranged on the side wall of the microwave vacuum chamber. The microwave vacuum drier is easier to be synchronously matched with a production line by feeding in a stepping way, microwave vacuum drying and a continuous drying way of cooling and discharging. Compared with a single-chamber microwave vacuum dryer, the microwave vacuum drier has the advantages that time for inflating the vacuum chambers after drying is complete, taking and placing feed plates and re-vacuuming after the feed plates are mounted is saved, so that working efficiency is improved; and the microwave vacuum drier is applicable to dewatering and drying for agricultural products, health care products, food, medicinal materials, fruits, vegetables, chemical raw materials and the like with high added-value and heat sensitivity, and used for low-temperature concentration of chemical products, removal of water of crystallization, dewatering and drying of traditional Chinese medicine extracts and enzyme preparations, and the like.

Description

Technical field [0001] The invention belongs to the technical field of material drying equipment, and in particular relates to a microwave vacuum dryer. Background technique [0002] Microwave heating is a kind of radiant heating. Generally, the frequency of microwave heating is 2450GHz, which makes the water molecules of the heated material oscillate, and the molecules rub against each other to generate heat, so that the inside and outside are heated at the same time, without the need for convection or conduction to transfer heat. Therefore, the heating speed is fast, the heat efficiency is high, the processing time is short, and the temperature inside and outside of the material is uniform, so energy is saved, the drying efficiency is high, and the drying quality is good. Since the boiling point of water is directly related to atmospheric pressure, the lower the atmospheric pressure, the lower the boiling point of water. For example, under one atmospheric pressure (101.3KPa), t...

AI Technical Summary

Problems solved by technology

[0003] The current microwave dryer generally has two forms: one is an in-line continuous conveying microwave dryer composed of a belt conveyor and a closed body equipped with a microwave generating device. The transmission is continuously conveyed through the microwave drying section to achieve dehydration and drying, and then the dried material is conveyed from the discharge end. It belongs to the microwave drying equipment for continuous feeding and discharging. It is 100°C, the drying temperature of the material is high, it cannot reach the low temperature drying condition, and the efficiency is low

The other is a microwave vacuum dryer with a single vacuum chamber and a microwave generating device installed on the upper part of the vacuum chamber. The middle part of the vacuum chamber is equipped with a turntable that can carry the material trays to be dried on a rotatable shaft. It is hoisted on the turret and kept relatively horizontal for rotary motion, so that the materials can be evenly dried by microwave. This kind of equipment belongs to discontinuous production equipment. One working cycle needs to complete loading, vacuuming, microwave drying, vacuum chamber intake, and discharge. Due to the single-chamber microwave vacuum dryer adopts a single-chamber structure, a drying process requires opening the vacuum chamber door, filling the materials with a tray and hanging them on the turntable one by one, and then closing the vacuum chamber door. After the vacuum chamber is inflated, the door of the vacuum chamber is opened to take out the materials one by one, so it cannot work continuously in and out of the material, which is inconvenient to synchronize with the production line, and the labor intensity is also high.

There is also a microwave vacuum dryer in the form of a horizontal single vacuum chamber with a relatively large length and diameter, which uses a multi-layer group of transport belts to rotate and carry dry materials. For example, Chinese invention patent application CN201010141441.5 discloses a continuous microwave vacuum drying Sterilization processing equipment, horizontal multi-layer microwave vacuum dryer is not conducive to making each layer of dry material receive uniform microwave heating, and the structure is complex

Images