Unreasonable ventilation and airflow organization is another key problem that cannot be ignored in the construction of cleanrooms for hollow capsule production lines. The core function of the cleanroom is to maintain a clean environment free of dust, microorganisms and other pollutants, and reasonable ventilation and scientific airflow organization are the foundation to ensure this function. However, in the actual construction process, due to improper design of air supply and return air systems and pressure difference control, a series of problems such as airflow dead zones, turbulent flow and cross-contamination often occur, which seriously affects the cleanliness of the production environment and the quality of hollow capsules.
The improper design of air supply and return air systems is the primary cause of unreasonable airflow organization. In the cleanroom design of hollow capsule production lines, the layout, air volume and wind speed of air supply and return air outlets need to be strictly matched with the production process and workshop layout. However, in many construction cases, the design of air supply and return air does not fully consider the particularity of each production process (such as glue mixing, dipping, drying, cutting, fitting, inner packaging, etc.), resulting in unreasonable airflow direction and uneven air distribution in the workshop. On the one hand, airflow dead zones are formed in local areas of the workshop. These dead zones have poor ventilation effect, and pollutants such as dust and microorganisms generated in the production process (such as dust generated during capsule cutting and microorganisms in the air) cannot be discharged in time, and will accumulate continuously, destroying the clean environment of the workshop. On the other hand, turbulent flow occurs in the airflow in some areas. The disordered airflow will not only affect the stability of the cleanroom environment (such as causing fluctuations in temperature and humidity), but also carry the dust and microorganisms generated in the production process to spread randomly in the workshop, increasing the risk of cross-contamination between different production links.
Cross-contamination caused by unreasonable airflow organization is a major hidden danger affecting the quality of hollow capsules. Hollow capsules are used as drug carriers, and their cleanliness requirements are extremely high. Once cross-contamination occurs between different production links (such as the cross-contamination between the glue mixing area with more dust and the inner packaging area with high cleanliness requirements), it will directly lead to the pollution of the capsule shell, affect the safety and effectiveness of the subsequent drug filling, and even cause the batch scrapping of products in severe cases. For example, the dust generated in the capsule cutting process is carried by turbulent airflow to the inner packaging area, which will adhere to the surface of the finished capsules, resulting in unqualified product cleanliness; the microorganisms in the low-cleanliness area spread to the high-cleanliness forming area, which may cause microbial contamination of the capsule shell.
In addition, the failure of pressure difference control between different functional areas is another important manifestation of unreasonable ventilation and airflow organization, and it is also a key factor leading to the diffusion of dust and microorganisms. In the cleanroom of hollow capsule production lines, different functional areas (such as raw material storage area, glue mixing area, forming area, packaging area, waste disposal area, etc.) have different cleanliness requirements, and reasonable pressure difference control is required to form an air flow direction from high-cleanliness area to low-cleanliness area, so as to prevent the diffusion of pollutants from low-cleanliness area to high-cleanliness area. However, during the construction process, due to the improper design of the air volume balance of the ventilation system, the unreasonable setting of pressure difference sensors, or the poor airtightness of the workshop enclosure structure, the pressure difference between different functional areas cannot reach the specified standard, and even reverse pressure difference occurs.
When the pressure difference control fails, the air flow direction between functional areas is reversed or disordered, which will directly cause the dust, microorganisms and other pollutants in the low-cleanliness area to spread to the high-cleanliness area. For example, if the pressure difference between the glue mixing area (low cleanliness) and the forming area (high cleanliness) is not up to standard, the dust generated in the glue mixing area will spread to the forming area with the air flow, polluting the glue solution and the forming capsule shell; the waste disposal area with more microorganisms will have air flowing back to the packaging area due to reverse pressure difference, resulting in microbial contamination of the finished capsules. At the same time, the failure of pressure difference control will also affect the normal operation of the cleanroom's airtightness, further exacerbating the problem of airflow disorder and pollutant diffusion.
In summary, the unreasonable ventilation and airflow organization, including the improper design of air supply and return air and the failure of pressure difference control, will not only destroy the clean environment of the hollow capsule production workshop, but also lead to the spread of dust and microorganisms, cause cross-contamination, and ultimately affect the qualification rate and quality safety of products. This problem is closely related to the design, equipment selection and construction quality of the cleanroom. Therefore, in the early stage of cleanroom construction, it is necessary to fully combine the production process characteristics of hollow capsules, optimize the design of ventilation and airflow organization, select matching ventilation and pressure control equipment, and strictly control the construction quality to ensure the rationality and stability of air supply and return air and pressure difference control.