Protection focus for a long time, people have been trying to find moistureproof prevent mildew and anti-corrosion effective means, to solve the problem of goods safety preservation. , focusing on the control environment water environment relative humidity control at about 50%, to be sure that most of the items for safety. In order to achieve this goal, people USES a variety of drying method. The traditional method mainly has the following three kinds, namely high temperature dehumidifier, dehumidifier at low temperature and moisture absorption agent desiccant three ways.
A, desiccant moisture way:
1, high-temperature dehumidification methods: high-temperature dehumidification heating mode is mainly adopted to bake desiccant, such as all kinds of electric heating and infrared drying oven, oven, etc. Due to their high working temperature, would spoil items made of organic material, at the same time, also can produce effect of heat treatment of metal materials, changes the properties of metal damage. And long-term continuous heating, also is not realistic. Therefore preserved as long-term security items, the high-temperature dehumidification way is not used.
2, low temperature dehumidifying ways: frozen desiccant dehumidification is mainly used at low temperature refrigeration type, its working principle is through the cooling device to reduce the condenser surface temperature, make the moisture in the air in the condenser cooling condensation dew, and then drop out. All seal in the space of water discharge in order to reduce the humidity in the air, low-temperature dehumidifier. Frozen dehumidification is by far the most effective and the safest, most economical a desiccant solution.
Methods: 3, vacuum drying of dry air contained in the vacuum to achieve the goal of removing moisture. Made up of enclosure and vacuum pump. Due to vacuum, so the cabinet and the door is under atmospheric pressure and the sealing requirement is very high, compared with the casing external dimensions, internal effective use of the space is little. And can only be done in a small box enclosure, when using, need to decompression, inconvenient, buy expensive. Application range is very small.
4, the moisture absorption agent desiccant way: general is placed in the sealed container desiccant silica gel. Defect is when saturated moisture absorption agent need to be replaced or artificial drying regeneration, long long maintenance work is quite complex; And, more importantly, because saturated time difficult to accurately predict moisture absorption agent, container humidity exactly how many can't depends on the degree of silica gel discoloration is not exact, which is not appropriate to replace moisture absorption agent in time.
Second, the occurrence and harm of mould:
1, mold mold unusually wide range, including the ascomycetes fungus door classes, algal bacteria, fungi imperfecti, etc, which have the role of industrial materials has hit more than forty thousand kinds. Mould transmission relies mainly on the spores, spore as small powder, the naked eye is not easy to observe. Spores are ejected from the mold, because of its small volume, light weight, along with the air flow movement and dust and float around the body and the movement of the object. Once meet appropriate development environment, can be grow, reincarnation, that is often said that the mold.
1) the conditions of 2, items, long mildew, humidity: environmental relative humidity is more than 60% mildew can grow. Greater than 65% RH, growth is accelerated, the humidity of RH80-95%, is a high-risk environment mold. 2), temperature: fungal mycelium in 8 degrees above ambient temperature can grow, 12 degrees, more than the growth rate increases as the temperature over 10 degrees, humidity in more than 60% of the environment, mold can cause harm to items. When the temperature in the 20 to 35 degrees, humidity in 75-95%, the mold can be explosive growth.
3, metal oxide corrosion occurrence and harm of oxidation corrosion of metal process is the moisture in the air, oxygen, lead to metal produce electrochemical reaction process. Scientific research proves that the metal oxidation corrosion air relative humidity, the critical value, the steel is 70%, copper 60%, 76% aluminum, iron is 63%, zinc 60%. The metal stored in above the critical value of environment, oxidation corrosion rate accelerated with the increase of air relative humidity value.
