Label：Pharmaceutical Equipment, Air Conditioning System, Monitoring and Control
Oct 27, 202112284
Clean technology is currently widely used in electronic semiconductors, pharmaceutical equipment, food hygiene, biotechnology, medical and other fields. With the advancement of technology, the requirements for clean rooms are becoming higher and higher. From the perspective of the clean room, this article talks about the application of automatic instrument control and monitoring technology in the clean room.
Modern clean room technology divides clean room design and construction, clean room testing and inspection, and clean room operation into three major categories, each of which covers automated instrument control and monitoring technology. The purification project is a highly systematic project, which includes the purification enclosure structure and the purification air conditioning system.
Whether the entire system is reasonable and whether it can ultimately meet the various indicators or parameters required by the air purification level and production process depends on the level of detection and automation of the instrumentation. For the entire clean air conditioning system, clean air conditioning units and ducts are an important part of this system. Its function is to filter, heat or cool the air, humidify or dehumidify, and send it to various places where it is needed. However, whether the air sent into the room meets the cleanliness requirements, and whether the air temperature and humidity meet the production requirements, needs to be realized by detection and control equipment.
● High precision of temperature and humidity control
● High precision of positive and negative differential pressure control
● High efficiency requirements of the filtration system
● High requirements for variable air volume adjustment
● Requires high stability and reliability
In view of the characteristics of clean room engineering, higher reliability and stability are required in terms of control instruments and detection instruments. This can not only achieve the purpose of process production, but also save energy and reduce consumption, reduce production costs, and protect the environment.
Maintain a certain micro-differential pressure between the clean room and the surrounding space according to the process requirements, which can be positive or negative pressure. The micro differential pressure can be controlled by the air supply port, the return air port or the residual pressure valve.
Differential pressure control is a very important link in the purification air conditioning system. Only by controlling the pressure difference in the purification area and ensuring a reasonable air distribution can the purification and process requirements be met. For example, the clean workshop must maintain a certain positive pressure so that the unpurified outside air will not enter the purification area to ensure the cleanliness level. And through the different pressure difference control of each purification area, the role of purification zone is achieved. In GMP, the pressure difference of different purification level areas should be controlled not less than +5Pa. Therefore, differential pressure control is very important for clean air-conditioning systems.
The control of cleanliness is mainly achieved through the filter and the room with a certain amount of air exchange. The performance of the filter and long-term clogging will affect the cleanliness of the air. Therefore, it is necessary to detect the status of the filter, but also to grasp the operating status of the fan and the air pressure of each air duct.
The air supply volume of a clean room is determined by the cleanliness level, but the air supply volume will inevitably be affected by factors such as dust production, pressure difference and other factors, resulting in increased equipment energy consumption and increased operating costs. If the system adopts a frequency conversion device, and then set up detection and control devices to adjust the exhaust air volume according to the characteristics of the production process, and successively change the air supply volume, it can avoid the need to turn on the exhaust fan when individual processes are not in production, which will cause electrical energy consumption. Due to the frequency conversion device, the fan speed can be changed according to the required air supply value of the system, thereby greatly reducing the power consumption.