Selection and performance comparison of vacuum dryer

Vacuum dryer is used for drying flaky, strip, granular and partial paste materials with good air permeability Some of them can also bake and burn the materials The vacuum dryer has the advantages of simple structure, convenient installation and long-term operation In case of failure, it can also enter the box for maintenance, which is convenient for maintenance Vacuum dryer is widely used in industry It is mainly used to dry small pieces of materials and fibrous materials Because the material dried by vacuum dryer has a certain shape, and it keeps a certain shape after drying The vacuum dryer is composed of several independent unit sections Each unit section includes circulating fan, heating device, separate or public fresh air suction system and exhaust gas discharge system Therefore, the number of drying media, temperature, humidity and tail gas circulation can be controlled independently to ensure the reliability of the vacuum dryer and the optimization of the operating conditions Vacuum dryer is widely used in the fields of pharmacy, food, biology, chemical industry and so on However, in each field, the selection criteria are different, because the requirements and parameters of drying materials in each field are quite different For example, in the food industry, the solid content of the material extract is generally large (over 65%), and the requirements of output, specific volume and appearance of the product are the key factors in the selection standard of the vacuum dryer There are two elements in the selection process of the food level vacuum dryer that should not be ignored: one is the consumption ratio of unit energy consumption, the other is the supporting equipment such as the pre-stage transportation and drying of raw materials After the product fine crushing and packaging As for the vacuum dryer used in biology and chemical industry, due to the different forms of products, the selection standard is extremely complex, so it needs to be very careful How to choose a vacuum dryer is to carry out a small sample test on the dried materials, which is very important Therefore, for equipment suppliers, whether they have material test equipment and experienced test personnel is a direct way for customers to measure the true capabilities of manufacturers Generally, qualified vacuum dryer manufacturers can provide customers with a report of technical parameters, including the actual evaporation of materials, dynamic drying vacuum, distribution of drying temperature, feeding amount, actual drying time, actual product capacity, unit energy consumption ratio, etc in a short period of time after material test, so as to facilitate customers to select equipment that can meet production requirements Model and specification The second step is to comprehensively investigate the design level and manufacturing capacity of manufacturers On the basis of the material test report, the manufacturer will generally provide a draft of technical design scheme and make a detailed statement of the design reasons in the scheme according to the production indexes and working conditions of the customer The technical design scheme is an important part to evaluate the manufacturer's manufacturing capacity of the vacuum dryer, especially the manufacturer's design description of the key technologies of the equipment, such as the design of the vacuum system, the design of the heating system, the design of the correction system, the design of the cleaning system, the design of the feeding and discharging systems, etc Another aspect of manufacturing capability is to investigate the actual use of manufacturers and users According to the list of users provided by the manufacturer, the customer can request to visit the site If the manufacturer does have sufficient strength, it will not refuse the reasonable request of the customer, and some can even provide multiple visit objectives for the customer to choose However, it is difficult for enterprises with limited manufacturing capacity or low technology level to achieve this The third step is to investigate the manufacturer's actual processing capacity and production scale At present, there are no more than three enterprises with serial design and production capacity in China, especially only one or two manufacturers with annual output of more than 10 vacuum dryers Therefore, it is very difficult for most domestic manufacturers to form the standardized processing of parts of vacuum dryer There are big problems in the product maintenance and exchange of parts and accessories provided to customers, which often directly affect the production efficiency of users In addition, due to lack of practical experience, the mechanical structure of equipment, rationality of configuration, accuracy requirements in manufacturing, etc It's impossible to think about it well However, due to the characteristics of large volume, many auxiliary equipment, high configuration requirements and complex intermediate links, it is not easy to maintain the long-term stability of the equipment The price of this kind of equipment is also relatively expensive Generally, users are optimistic about its drying capacity and technical advantages, and use a large amount of money to purchase, so they hope to recover the cost as soon as possible to improve the economic efficiency of the enterprise Therefore, when purchasing equipment, we must choose manufacturers with scale, practical design and manufacturing experience and reliable after-sales service assurance system to rest assured Of course, the price of vacuum dryer provided by such manufacturers is generally a little high, but for users, there is a sense of security in use, and pnell drying reminds customers not to covet the low price for a while Ring the whole picture.