With the development of more than half a century, the application of clean technology is more and more extensive, and the technical requirements are more and more complex. At present, its representative application fields are microelectronics industry, medicine and health and food industry. Its application fields mainly include:
1. Microelectronics Industry
Microelectronics industry is the most demanding industry for clean rooms. With the development of large scale integrated circuit (LSI) and VLS1, the requirement of dust control is getting higher and higher. In IC manufacturing process, the thinner the graphic size (expressed by line width) is, the smaller the controlled particle size (usually 1/10 of line width) is, and the lower the dust content is. In addition, modern industrial liquid crystal and optical fiber production require the same cleanliness.
2. Medical industry
(1) The Pharmaceutical Production Management Specification (GMP) of China has been implemented nationwide, and different cleanliness requirements have been put forward for the corresponding process and production environment. In view of the preparation of raw materials, powder, injection, tablet, production of large infusion, filling and other processes, the cleaning standards of clean and controlled areas were formulated. In addition to limiting the size and quantity of dust particles in the air, biological particles (the number of bacteria) also have clear limits.
(2) Hospital leukemia treatment rooms, burn wards and operating rooms must also adopt air purification projects according to specific conditions to prevent bacterial infection in the air and control the treatment environment.
3. Food industry
Sterile filling is the most representative application of clean technology in food industry. Sterile packaging of food (such as soft packaging fresh juice, fresh milk, etc.) is much better than high temperature sterilization canned food in maintaining the color, aroma, taste and nutrition of food. Aseptic packaging is a process of packaging in a clean environment. In addition to aseptic filling, air purification engineering plays an important role in the cultivation, isolation, inoculation and expansion of pure bacteria in food fermentation process, preventing bacterial contamination and improving product quality.
In genetic engineering, medicine, pathology, molecular biology, national defense research, etc., it is usually necessary to operate in a sterile and dust-free environment. On the one hand, specimens are required to be contaminated by microorganisms, on the other hand, research materials, such as cancer viruses and pathogens, are at high risk. Radioactive substances, if not spilled, endanger the health of operators and the pollution ring. Environment. For this kind of experimental operation, two-stage isolation is generally required. In the first stage, biosafety cabinets are usually used to isolate workers from pathogens and other dangerous specimens. The second level is to isolate the laboratory workspace from other environments. This kind of laboratory is different from the general clean room, it is in a negative pressure state.
5. Feeding of experimental animals
In order to ensure the long-term safety of drug and food inspection and the reliability of pathological research results, laboratory animals are required to breed and reproduce in a clean environment. From the point of view of controlling microorganisms, the breeding environment of experimental animals for medical and biological experiments can be divided into three types: isolation system, semi-isolation system and open system. The first two systems require animals to be sterile (including bacteria, viral parasites, etc.), or to carry only a small number of known microorganisms, or not to carry certain pathogenic bacteria, etc.
Air purification engineering is also widely used in aerospace, precision machinery, instruments, fine chemicals and other industries.