Five characteristics of glass-lined reactor

After entering the 21st century, with the rapid development of science and technology, the enamel industry has achieved leapfrog development, and has made all-round progress in product structure adjustment, industrial upgrading, technological progress, etc. Enamel and glass lining materials have become one of the most promising materials in the field of materials.

Characteristics of glass-lined products

Glass-lined products are widely used in chemical, pharmaceutical, pesticide, dye, light industry, food, metallurgy and national defense industrial systems, and play a huge role in national economic construction.

Why do many industries choose glass-lined products? Firstly, the characteristics of glass-lined products should be discussed.

At present, with the rapid development of science and technology in the world, new materials continue to emerge, and glass-lined materials have not been replaced by new materials, but have continued to develop. The reason is that glass-lined materials have five characteristics.

1. Corrosion resistance

The glass layer of the glass glaze with silica as the main body, which is fired at high temperature, has strong chemical stability and can withstand the corrosion of various concentrations of organic acids, inorganic acids, weak alkalis and organic solvents (hydrofluoric acid and fluorine-containing ionic media, as well as hot phosphoric acid above 180 ° C and strong alkaline solution above 50 ° C are not applicable).

In particular, the stainless steel materials commonly used in the chemical and pharmaceutical industries are not resistant to the corrosion of hydrochloric acid, resulting in the use of glass-lined products.

The acid resistance of the glass-lined layer is different due to the different composition of the enamel formula, and the control temperature of the enamel is also different. Generally speaking, enamel with higher silica content will have better acid resistance of the glass layer with slightly higher enamel temperature. The alkali resistance of the glass layer with good acid resistance will be weak. In the process of chemical engineering, acid and alkali are often alternated. Therefore, the comprehensive corrosion resistance should be considered when selecting glass-lined products.

Glass lining has good comprehensive performance in corrosion resistance, mechanical impact resistance, wear resistance and temperature change resistance.

2. Non-adhesiveness

The surface of the glass layer is smooth and has few dead corners. It is not easy to adhere to materials and easy to clean. It is very necessary in some production processes.

For example, the excellent non-stickiness of glass-lined equipment highly meets the needs of pharmaceutical equipment, and glass-lined equipment is widely used in pharmaceutical equipment. Where there is a need for systematic cleaning, glass-lined equipment has become the object of choice for designers due to the fact that the glass surface is not easy to adhere to materials. The non-stickiness of glass surface is comparable to that of polytetrafluoroethylene.

3. Isolation

After the internal surface of the equipment is coated with a glass-lined layer, the medium does not directly contact the steel body containing iron. Therefore, in the production process, the medium cannot dissolve iron ions, which is particularly important for the production of drugs and dyes.

For example, in the pharmaceutical process, there are strict requirements for the iron content of drugs. In the dye industry, if the dye dissolves into iron ions, the color will be affected.

4. Insulation

The insulating property of the glass layer is good, and it is 0 The 4mm glass layer can withstand the impact of 20kV high voltage. Therefore, glass-lined products are applicable to the process of dielectric charged operation and the process occasions where electric charges will be generated in production. In some chemical processes, materials need to be charged to accelerate the process. The insulation of the glass layer is suitable for this situation.

5. Freshness

The molecular structure of glass is stable, impermeable and insoluble. It has good fresh-keeping properties for liquid food, brewed products and beverage products, and can keep the true fragrance of its products for a long time.

For example, most alcoholic drinks in the market are filled in glass bottles, mainly using the freshness of glass. This feature is also retained in glass-lined products.

matters needing attention

The chemical process is ever-changing, and there are many kinds of industrial materials. It is difficult to briefly describe which materials to choose glass-lined products, but the following selection precautions should be observed:

1. Its materials and requirements shall meet the five characteristics of glass lining.

2. The resistance to sudden temperature change of glass-lined equipment refers to the performance of the glass-lined surface of the product or the metal substrate on its reverse side to undergo sudden temperature change. The product shall control the cold change temperature of 110 ° C and the hot change temperature of 120 ° C. It is not suitable to use when the temperature changes frequently in production and the temperature changes rapidly close to the limit value.

3. The minimum service temperature of the glass layer can reach - 40 ℃ and the maximum service temperature can reach 300 ° C. The structure of the glass layer can remain stable within this range. However, the metal base material shall comply with relevant design regulations.

4. The glass layer is a non-metallic material and belongs to brittle material. The glass surface cannot bear the direct impact of solid materials. It is not suitable for those who directly put solid materials into the container mouth.

5. Solid hard crystalline particles will be produced in the process medium, so microcrystalline enamel with better wear resistance should be selected.