Compressed Dry Air
Compressed Dry Air (CDA) is a primary component of overall energy use in most industrial facilities. Compressed air acts as an energy source for a variety of tools and machinery, and it is often an important and well integrated part of many production processes.
The compressed air must be free of contaminants regardless contact or non-contact with any products. The cleanliness of the compressed air is crucial especially in food, pharmaceutical and semiconductor industry. ISO 8573 specifies purity classes of compressed air with respect to particles, water and oil independent of the location in the compressed air system. Each is categorized and assigned a quality class ranging from class 0, the most stringent, to Class 9. The end user-user is responsible for defining the air quality required for their particular application or process.
It is important for the user to routine monitor and assess the quality of their compressed dry air. The quality of the compressed dry air could be varied from time to time depending on dryer type and filter performance, intake air quality, maintenance program, piping and distribution system cleanliness and pattern of use.
Dew Points / Water Content
Atmospheric air contains water vapor, water vapor enters the system which begins to condense into liquid water when the air being compressed. This moisture will spoil food products, cause pneumatic machinery failure and promote bacterial growth in the compressed air piping. Compressed air systems serving the food processing industry must maintain dry, moisture free conditions mitigating the risk of micro-organism growth.
Liquid Oil and Oil Vapor ( As Total Oil Content)
Several air compressor technologies available for the industrial use where some require lubrication in the compression chamber for cooling and sealing purposes, and others that operate less lubricant in the compression chamber. Lubricated compressors are typically less expensive to purchase and have a lower cost of ownership. While lubricant free compressors generally have a higher initial cost and greater maintenance costs over the life cycle of the equipment; the compressor presents no risk of lubricant migrating into the process air.
Solid Particles
In a general industrial area, one cubic meter of untreated compressed air can contain close to 200 million dirt particles and other substances. When the ambient air is compressed, the concentration of solid contamination will reach significant proportions. Solid particle smaller than 40µm in size is barely visible to the naked eye. Even a well maintained and routinely changed intake filter will allow solid particles to enter the air system.
Microbes (Viable Counts/ Yeast & Mould Counts)
Many kinds of microorganisms can live in compressed air systems, including bacteria, mold and yeast. These organisms thrive in damp, dark places (such as air compressor coils or compressed air piping), and they can grow anywhere where there are suitable conditions. The risks of microbial contamination are directly related to the application in which the air will be used. Compressed air microbial contamination is a much bigger concern for the food, pharmaceutical and medical industries
Nitrogen Purity Test
Nitrogen is used in a broad range of different industries. As an inert gas, nitrogen gas uses range from food processing and medical testing to the purging of crude oil pipelines. Nitrogen is inherently a very dry and clean gas and it has a low dew point and should be supplied clean of contamination. From generation to delivery, the gas is introduced to various connection points, hoses and storage vessels before it is released to the final process.
Every application that requires the use of nitrogen gas needs the nitrogen at a specific purity level for optimal performance. The purity level from 95 % ‒ 99.999 % may seem small but the presence of oxygen in the nitrogen gas might can result in problems with flammable substances.