FRP Food storage tank
1. Performance requirements of fermentation equipment
There are mainly three types of corrosive media in the fermentation industry: one is the corrosion of its products or intermediates in the production process and the product itself, such as: citric acid, acetic acid, salts in soy sauce, etc.; the other is necessary in the process Various auxiliary materials and cleaning and sterilization products, such as: various salts, inorganic salts (hydrochloric acid, sulfuric acid, sulfurous acid, etc.), alkalis (sodium hydroxide, ammonia); the third is a mixture of the above two, and should be environmentally friendly Treated waste gas, waste water, etc.
The material is non-toxic and can contact food
Fermentation equipment must meet the hygienic requirements of the food.
Conducive to the prevention and control of polluting bacteria
Contaminating bacteria or bacteriophages in the fermentation process are the enemy of the fermentation industry. Infections not only hinder the growth of production strains and the synthesis of products, disrupt the normal production and management order, but also affect the product quality of the next process, and severely cause failure. Tank, put the fermentation liquid into the sewer, causing great loss in production. Therefore, the equipment is required to have no dead ends, no leakage, and its material is free of dirt, and it is not easy to breed or retain bad bacteria.
Have a certain strength and rigidity. In the fermentation industry, in addition to storage tanks for finished products and raw and auxiliary materials, some equipment has requirements for temperature, pressure, and agitators, such as various fermentation tanks, neutralization tanks in the monosodium glutamate industry, ion exchange columns, and vacuum concentration for citric acid production. Cans and so on. Therefore, there are certain strength and rigidity requirements for the materials of the manufacturing equipment.
2. Material status of existing fermentation equipment
At present, most of the equipment used in the fermentation industry is roughly divided into three types of materials. The first category is carbon steel composite, which is lined with rubber, glass fiber reinforced plastic, stainless steel, plastic and acid-resistant ceramic tiles, etc.; the second category is integral stainless steel; the third category is integral plastic (PVC, PP, etc.) carbon steel composite and plastic equipment , The cost is moderate, and generally can meet the requirements of general corrosion resistance, but the performance of the lining material of carbon steel composite equipment is very different from that of carbon steel, which brings many difficulties to construction and maintenance, and the lining is easy to fall off, causing equipment corrosion And pollution to the internal medium. In addition, the maintenance cost increases and the service life is greatly shortened. Moreover, once the corrosion-resistant lining of the container penetrates, the carbon steel shell will be severely corroded, and even the entire equipment will be scrapped. For pressure tanks, serious accidents such as explosions may also occur. Plastic equipment has excellent corrosion resistance and can be used in a variety of media. But plastic equipment is basically thermoplastic engineering plastics, the use temperature is not high (such as PVC, usually below 70 ℃), or brittle at low temperature, easy to crack (such as PP, etc.), low strength, easy to aging, so the application is limited . The overall stainless steel equipment has good overall corrosion resistance, convenient processing and maintenance, high strength, and good temperature resistance. It is often used in some critical equipment with more demanding conditions. However, in actual use, there are also some problems, such as corrosion and bacteria contamination. If the solution is not good, not only will it not be able to exert its advantages, but it may also cause greater losses.
Third, the characteristics of FRP equipment
Meet the requirements of food hygiene. Whether it can meet the requirements of food hygiene is the most fundamental requirement of fermentation equipment. Whether FRP products can meet the sanitary requirements, the key to the choice of lining resin is food-grade resin.
Lightweight and high strength. The specific gravity of FRP is only 1.4-2.0, while the tensile strength of fiber-wound FRP can reach 300-500Mpa, which exceeds the ultimate strength of ordinary steel, and has the advantages of convenient transportation, installation and maintenance.
Excellent corrosion resistance. One of the major characteristics of FRP is its good corrosion resistance. Through the selection of the type and grade of resin and the appropriate molding process, FRP products that are resistant to a variety of acids, alkalis, salts and organic solvents can be produced.
Good surface performance and easy cleaning and sterilization performance. Because the glass fiber reinforced plastic is integrally formed, there are no joints, and the inner wall is smooth. When in contact with chemical media, there are few corrosion products and scaling phenomena on the surface, and no bacteria and microorganisms breed. Therefore, it does not pollute the medium and is easy to clean. After special inspection by the food and drug management department, FRP has reached the requirements of the food brewing and pharmaceutical industries.
Good designability. FRP is a composite material that can change the type, quantity ratio, and arrangement of reinforcing materials to meet different performance requirements.
Good construction technology. Uncured resins and reinforcing materials have the ability to change shapes, so they can be easily processed into desired shapes through different molding methods and molds.
Cost and operation are low. The price of glass fiber reinforced plastics is higher due to the raw materials used. Generally speaking, the price of FRP equipment is higher than that of carbon steel equipment and some plastic equipment, but lower than that of stainless steel and some other non-ferrous metal equipment. However, due to the advantages of light weight, good corrosion resistance, and long service life of FRP, its installation, use and comprehensive cost are low.