Principle and process of air purification in the weighing room

(1) Brief introduction of the principle of air purification
In the weighing room of the biopharmaceutical industry, the air purification principle is scientifically and rigorously designed. First of all, the weighing room adopts a vertical unidirectional flow, which allows the air to flow in a specific and orderly direction, laying the foundation for the creation of a clean environment.
In this process, the initial effect filter plays a crucial first check role, which can remove impurities such as large particles of dust particles in the air stream to avoid these large particles into the subsequent air treatment link and work area. The air after the pretreatment of the primary effect filter will then be filtered through the secondary effect filter, which can further intercept the medium-sized particles, fully protect the subsequent high-efficiency filter, and avoid the high-efficiency filter due to premature blockage by too many impurities and other conditions affecting its service life and purification effect.
Finally, under the stable pressure provided by the centrifugal fan, the air will pass through the high-efficiency filter, the high-efficiency filter with its high-precision filtration capacity, can intercept very small particles, such as intercepting particles above 0.3 microns, and the filtration efficiency can be as high as 99.97% so that the air meets the cleanliness standards required for biopharmaceutical production. Moreover, the operating area of the weighing room and the external environment will form a relative negative pressure, which can ensure that the dust in this area will not easily spread to the outside, effectively preventing the external unclean air from entering the weighing room, and also protect the external environment to ensure that the entire weighing operation is carried out in a relatively closed and clean air environment.
(2) Specific air purification process
After the air enters the weighing chamber, it goes through a number of treatment stages in order to achieve purification and achieve a state that meets the requirements.
At first, the air first enters the return air box, where it will first come into contact with the primary filter, the primary filter is like a "thick screen", which intercepts the impurities such as those visible to the naked eye or relatively large particles of dust particles in the air stream to complete the initial purification of the air. The air after the initial effect filtration continues to flow to the medium effect filter, and the medium effect filter further performs fine treatment on the air, intercepts the particles that are missed by the initial effect filter and are relatively smaller again, and plays a connecting role to better protect the subsequent high-efficiency filter.
Then, the air after the primary and middle-efficiency filter treatment is driven by the pressure generated by the centrifugal fan and is sent to the high-efficiency filter. Hepa filters are the key to ensuring A high level of air cleanliness by intercepting extremely small particles and allowing the air to meet the requirements of biopharmaceutical manufacturing, such as 100 (ISO 4.8) vertical laminar flow protection standards, which refer to the 2010 GMP Level A requirements.
The clean air will be sent to the bellow body, and most of the clean air (usually about 85%-90%) will pass through the uniform air supply network board to form a uniform vertical air supply stream and stably enter the working area of the weighing room to create a high cleanliness environment for the weighing operation. A small part (about 10%-15%) of clean air will be discharged from the equipment through the air volume adjustment plate so that certain exhaust air is formed in the equipment so that the operating area of the weighing room and the external environment form a relative negative pressure state. In this process, because the operating area is a stable unidirectional flow, even if there is dust emitted in the operating area, it will also be under the influence of one-way airflow, with the flow line being captured by the primary and medium efficiency filter, and all the airflow treated by the high-efficiency filter, whether it is air supply or exhaust, does not carry residual powder, effectively avoiding secondary pollution. Ensure that the entire air purification process forms a benign and effective cycle, and continue to provide a clean air environment for the weighing work of biopharmaceuticals.