Views: 63 Author: Site Editor Publish Time: 2021-08-13 Origin: Site
In order to prevent fresh cocoons from appearing with moths, mildew and maggots, the cocoons purchased at the cocoon station generally need to be pupated and dried in time, and the fresh cocoons are dried into suitable dry cocoons for silk reeling factories or other silks. Used by enterprises all year round. The drying of silkworm cocoons is also often referred to as cocoon drying. The purpose of its drying is to use a dryer machine to dry and kill silkworm pupae and parasitic fly maggots while removing an appropriate amount of water to prevent the deterioration of maggots, moths and molds, and to facilitate storage. When the silkworm cocoons are drying, it is necessary to protect the cocoon layer as much as possible, to make it relax well, to properly denature the sericin, to reasonably improve the cocoon boiling resistance of the cocoon layer, and to meet the silk reeling requirements.You can understand why you should use a cocoon dryer from the following two aspects
1. The basic concept of cocoon dryer machine
2.Cocoon dryer machine principle
(1) Balance moisture: Under certain environmental conditions such as temperature and humidity, after a certain amount of moisture is released from the material, the weight of the material no longer changes with time, that is, when the water vapor pressure changes the surface of the material and the water in the air Compare with steam. When the pressure is equal, the moisture contained in the material is the equilibrium moisture. Its value is related to the material itself and is also related to the temperature and humidity of the environment where the material is located.
(2) Free moisture: the moisture of the material after subtracting the equilibrium moisture from the actual moisture of the material.
(3) Drying rate: the percentage of dry cocoons in fresh cocoons.
Fresh cocoons contain a lot of water, and the water content is generally as high as 60%. The cocoon layer accounts for 17%-24% of the total fresh cocoons, and the water content is 11%-17%; the pupa body accounts for 83%-76% of the fresh cocoons, and the water content is 74%-78%. When the cocoons are dried to a suitable level, the moisture regains of suitable dry cocoons is 10%-12%. Therefore, drying cocoons is mainly to dry the pupae in the cocoons.
The water contained in the fresh cocoon includes free water and equilibrium water. What the cocoons need to dry is free water.
The principle of cocoon drying is to evaporate and escape the surface water of the cocoon through a dryer machine so that the difference in water content between the surface and the inside of the cocoon appears. The water inside the pupa diffuses to the surface to evaporate so that the water content of the pupa is continuously reduced to reach the specified moisture regain. Dry cocoon. Specifically:
(1) Surface evaporation: The heat medium first acts on the surface of the cocoon to increase the temperature of the cocoon layer, and the water in the cocoon layer diffuses outward and evaporates from the surface.
(2) Internal diffusion: heat energy is transferred to the cocoon cavity through the cocoon layer, increasing the temperature of the cocoon cavity. The pupa body in the cocoon cavity is heated and diffused inside. The water reaches the surface of the pupa and evaporates, leaving the cocoon cavity in a wet state. The water vapor in the cocoon cavity continuously escapes with the help of the temperature and humidity difference between the inside and outside of the cocoon cavity, so that the water in the fresh cocoon is removed through continuous internal diffusion and surface evaporation.
The automatic circulating hot air cocoon drying machine adopted by Sichuan Nanchong Shouchuang Technology Development Co., Ltd is a new generation of cocoon drying equipment developed according to the standard. It has the characteristics of environmental protection, energy-saving, stability, cocoon preservation, simple operation and labor-saving, and can meet the requirements of drying equipment. Provide customers with the best equipment