Oil-free compressed air

Air knives can be installed for about USD 750-800 per bath if an oil-free, compressed air source is available. Fog sprays can be installed also for about USD 750-800 per bath if a deionized... 

L.4.4 All grease, oil, paint, laitance and other undesired materials shall be removed from the surfaces to be grouted. The roughened concrete snrface shall be blown with oil-free compressed air to remove all dnst and loose particles. When cementitions grout is used, the concrete smface shall be thor-onghly soaked with water imtil absorption stops, and any excess water shall be removed. When epoxy grout is used, all surfaces shall be kept dry before application. 

To describe guideline for the validation of the oil-free compressed air system... 

An oil-free compressed air system is normally used in aseptic areas and often may be involved with product contact. 

The identity test for oil-free compressed air must show a chromatogram with no additional peaks other than those obtained with the air standard. 

Oil content of oil-free compressed air should be not more than 0.01 ppm. Frequency... 

Compressed air. Oil-free compressed air is produced in rotary screw compressors. It is stored in a stainless steel receiver, then passes through a l- im filter for particle removal and two air dryers to assure complete removal of moisture traces. It is delivered to the plant via a stainless steel loop that supplies all use points and has a filter and regulator. 

In most cases, the nonsterile containers must be cleaned in line (e.g., inverted, blown with clean, dry, oil-free, compressed air from a probe in the bottom of the container, then sucked out, with vacuum sited at the neck). The resulting dislodged particles are then sucked away from the container while the air probe is being withdrawn. 

Fig. 3. Process flowsheet for cellulase production in wheat bran culture [25]. A Submerged seed culture of T. viride, B oil-free compressed air C air filter D inoculum E exhaust air F sample collection G centrifugal pump H automatic wheat bran culture of T. viride I water spray I ammonium sulfate, alcohol and water J conveyor belt J screw conveyor K hopper L extraction column M storage tank centrifuge 0 precipitation P mixing tank Q ion-exchange column R membrane concentrator S spray dryer T filter press U rotary dryer V mixer W cellulase preparation and salt stabilizer... 

The plant has two reciprocating oil-free compressors, with a total capacity of 20 m3/h. The oil-free Compressed Air is supplied to a stainless steel air receiver. The air then passes through the air filter along with the oil and water separator system and passes through the air dryer and is distributed through S.S. use points in the three buildings. Terminal sterile filtration (0.01 pm) is used at critical use points. 

Open containers, e.g. securitainers or bottles, should always be inverted, blown with clean dry, oil-free compressed air injected by a dip tube from the base and vacuum sucked to remove as many particles as possible. 

Fig. 37. Diaphragm pump for producing oil-free compressed air, mounted on a multipurpose motor (Firm 126 s photograph)...

Excellent surface preparations for porous surfaces include blasting with oil-free compressed air, abrasive media, or high pressure water (dry time is a must in this case) and grinding or wire brushing followed by oil-free dry compressed air blasting. For nonporous substrates, solvent wiping with clean cloth followed immediately by a clean cloth dry wipe is the preferred approach. 

The prefilter nsing regenerable porous filter elements, such as sintered bronze powders, sintered stainless steel powders or mesh, polyethylene or polypropylene, with pore sizes of 5-25 pm, which will remove the heaviest contamination and protect the heat exchangers in the dryer. Oil- and dirt-laden compressed air flows through the filter element from the inside to outside. The coarse particles of dirt and pipe scale are retained on the inside of the prefilter. Oil, water and the remaining fine particulate matter then pass through the prefilter to a sub-micrometre filter. The use of such filters has become an essential part of achieving oil-free compressed air. 

Oil-free compressed air stiU coutains hydrocarbon vapours and odours, which in the food (especially dairy), brewery and pharmaceutical industries must be removed. To effect this removal, an activated carbon filter element should be used. Such elements are normally incorporated into another filter stage, immediately downstream of the high efficiency oil removal filters, where they should adsorb the hydrocarbon vapours and organic odours. 

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