Novel freeze dryer capable of recovering condensate water and operating method of freeze dryer

Abstract

The invention discloses a novel freeze dryer capable of recovering condensate water and an operating method of the freeze dryer. The novel freeze dryer comprises a refrigerating system, a condensate water recovering system, a waste heat recovering and heating system and a defrosting system. The refrigerating system comprises a refrigerating compressor, a condenser with a built-in condensing coiledpipe, a liquid storage tank, throttle valves, electromagnetic valves, an evaporator with a built-in evaporating coiled pipe, and a cold trap with a built-in coiled pipe and a heating coiled pipe. Thecondensate water recovering system comprises a freeze drying box, a box trap valve and a vacuum pump. The waste heat recovering and heating system comprises a cooler, electromagnetic valves, circulating pumps, a heater, an electric valve and an oil tank. The defrosting system comprises a stop valve, a water collector, electromagnetic valves and the heating coiled pipe. Heat is sufficiently and reasonably utilized, electricity consumption is reduced, energy is saved, the freeze drying economic benefits are improved, the batch production efficiency of drying is increased, the influences of theenvironment temperature on the condensing temperature are overcome, and the stable control over the condensing temperature and the efficient operation of the systems are well guaranteed.

Description

technical field [0001] The invention relates to a novel freeze dryer capable of recovering condensed water and an operation method thereof, belonging to the technical field of refrigeration. Background technique [0002] Vacuum freeze-drying technology is to cool the wet material to the temperature below the eutectic point of the material, so that the water and water vapor inside the material and inside the freeze-drying box become solid ice, and use the vacuum system to create a vacuum condition for the freeze-drying box. The ice is sublimated into water vapor by direct heating in the environment, and then the water vapor is continuously removed by the vacuum system, so as to achieve the purpose of drying the material. There are two problems with existing drying equipment. One is that when drying a large amount of food such as seafood or fruits and vegetables, through the three stages of pre-freezing, sublimation drying and analytical drying, a large amount of free water a...

AI Technical Summary

Problems solved by technology

One is that when drying a large amount of food such as seafood or fruits and vegetables, through the three stages of pre-freezing, sublimation drying and analytical drying, a large amount of free water and bound water will become water vapor through solidification and sublimation, and then be cooled. The trap captures and condenses on the surface. Most of the existing freeze-drying equipment captures and solidifies water vapor directly through the cold trap in the vacuum system, which is not properly collected and utilized, resulting in a waste of resources, especially for large-scale freeze-drying equipment. The cold trap will capture a large amount of moisture volatilized by the materials during the freeze-drying process. The moisture stored in the materials to be dried, especially fruits and vegetables, has good health value and can be recycled.

In addition, the condensed water on the surface of the cold trap needs to melt as soon as possible to start a new freeze-drying process, relying on natural melting takes a long time, which affects the efficiency of batch drying

The second is that during the freeze-drying process, the pre-freezing stage needs to be reduced to and kept at a very low temperature, which requires more energy to take out and release the heat in the freeze-drying box, and requires refrigeration and cooling during the sublimation and desorption drying stages. Heating works intermittently to maintain a constant drying and dehydration temperature. During this period, it is necessary to repeatedly take out heat and add heat. On the one hand, the existing freeze-drying equipment adopts a refrigeration cycle to cool down, and at the same time discharges the heat in the freeze-drying box. Adding heat to the freeze-drying box, but also using electric heating to raise the temperature, there is a lot of energy waste

Images