Application of industrial microwave equipment in honeycomb ceramic drying

　　Microwave drying stereotypes in honeycomb ceramics are mainly used in honeycomb ceramics, ceramic foam, dry stereotypes. The special ceramic ceramic drying is one of the important process of ceramic production process, quality defects of ceramic products are caused by improper drying.

　　Due to the strong penetration of microwave, it can penetrate into the interior of the sample, and the temperature of the sample center rapidly increases.

　　According to the practical application of the manufacturer, it is concluded that the microwave drying and shaping equipment has the following advantages:

　　1, the product drying and shaping quality is good, no cracking, foam aperture uniform.

　　2, easy to control, easy to operate, flexible; due to the adjustable output power of microwave, conveyor speed adjustable, so different materials can be used.

　　3, save time, high output, low energy consumption; through the actual production of the factory, the drying time is infrared drying 1/5, saving energy 1/3.

　　4, the production intensity is small, labor saving, the province of the process, in particular, and easy to connect with the automatic production line before and after the process to reduce the number of handling; save manpower, labor efficiency is greatly improved.

　　5, environmental sanitation, no pollution, no more "three wastes" problem.

　　Classification of drying technology:

　　According to whether the drying system can be divided into control, natural and artificial drying, artificial drying is controlled by the drying process, it is also called forced drying.

　　According to the different methods of drying classification, can be divided into:

　　Convection drying, which is characterized by the use of gas as a drying medium, the speed of the body surface at a certain speed, so that the body can be dried.

　　Radiation drying, which is characterized by the use of infrared, microwave radiation, such as electromagnetic radiation, exposure to the dried body to make it dry.

　　Vacuum drying, which is a method of drying the blank in the vacuum (negative pressure). The green body does not need to heat up, but need to use the pumping equipment to produce a certain negative pressure, so the system needs to be closed, it is difficult to continuous production.

　　Combined drying, which is characterized by the use of more than two kinds of drying methods to give full play to their respective strengths, complementary advantages, often can get a better drying effect.

　　There are some drying method, the drying system is divided according to continuous intermittent and continuous dryer dryer. Continuous dryer can according to the direction of movement with drying medium body is divided into upstream and downstream, Francis: according to the shape of the dryer is divided into different room type dryer, tunnel dryer.

　　Microwave drying technology:

　　Microwave is a kind of electromagnetic wave between high and far infrared rays, O.001 wavelength is 1m, frequency of 300-300000MHz. microwave drying with microwave irradiation blank electromagnetic field, the magnitude and direction of changes periodically with time so that the inner polar water molecules with high frequency alternating electric field changes, the dramatic molecular rotation occurred the friction is converted to heat, the body achieve uniform temperature to achieve the purpose of drying. The microwave penetration ratio of far infrared ray is much larger, and the frequency is small, the greater the depth of half power microwave characteristics of microwave drying:

　　(1) uniform fast, this is the main feature of microwave drying. Because the microwave has great penetrating power, heating can make the medium directly generate heat. No matter how the shape of a complex body, heating is uniform and fast, which makes the body fast dehydration, stripping uniformity, small deformation, not easy to crack.

　　(2) the selective, microwave heating and material properties, the microwave field in a certain frequency in water due to its dielectric loss than other materials, so the water absorbing material other than do a much larger amount; at the same time as the microwave heating is inside and outside at the same time, the water can be quickly heated and direct evaporation, so the ceramic body can be heated and release in a very short period of time.

　　(3) the high thermal efficiency, sensitive reaction, due to heat directly from drying, heat loss in the surrounding medium is few, and the microwave heating cavity itself does not heat, do not absorb the microwave emission in all body, high thermal efficiency.

The microwave heating device mainly consists of a DC power supply, microwave tube, connecting waveguide, several heater and cooling system components and microwave heating microwave heater in the field can be divided into the form of a standing wave resonant waveguide traveling wave field heater, heater, radiation type heater, slow wave type heater and so on.

　　So, in order to better play the advantages of microwave technology, in addition to the use of mixed or hybrid heating drying technology, strengthen the research on the interaction mechanism between ceramic materials and microwave dielectric properties of the strengthening of ceramic materials, the basic data between the medium consumption and the microwave frequency and temperature test, and microwave drying process and equipment improvement the technical committee of ceramic industry services.