Aux 1 Unit 7 Q5

In an air supply meant for pneumatic control systems, several contaminants can be present, each posing a potential risk to the system’s performance, reliability, and longevity. Here are the main contaminants that may be found:  

1. Clean Air Act: Battling Contaminants in Pneumatic Components – Fluid Power Journal

1. Water:

• Source: Atmospheric air naturally contains moisture, which can condense within the compressed air system due to temperature and pressure changes.   1. Understanding Compressed Air Humidity: A Comprehensive Guide – Ceccato www.ceccato.com
• Forms: Water can be present as vapor, liquid droplets, or even ice in colder sections of the system.   1. How Do I Control Contaminants In My Compressed Air System? – JHFOSTER jhfoster.com
• Problems:
  • Corrosion: Promotes rust and corrosion in pipes, valves, and other components.   1. How Contaminants In Compressed Air Can Affect Processes | JHFOSTER jhfoster.com
  • Freezing: Can cause blockages and malfunctions in cold climates.
  • Washing Away Lubricants: Removes lubricants from moving parts, leading to increased wear and tear.
  • Contamination: Can carry other contaminants throughout the system.   1. Clean Air Act: Battling Contaminants in Pneumatic Components – Fluid Power Journal fluidpowerjournal.com

2. Oil:

• Source: Primarily from the lubricating oil used in oil-lubricated compressors. Even with oil separators, some carry-over into the compressed air is possible.
• Forms: Oil can be present as aerosols, mist, or vapor.   1. Clean Air Act: Battling Contaminants in Pneumatic Components – Fluid Power Journal fluidpowerjournal.com
• Problems:
  • Clogging and Sticking: Accumulates in valves and actuators, causing them to stick or malfunction.
  • Instrument Interference: Can affect the accuracy and reliability of pneumatic instruments.
  • Contamination: Can contaminate products or processes, especially in sensitive applications like food or pharmaceuticals.
  • Fire Hazard: In some cases, oil mist can create a flammable atmosphere.

3. Particulate Matter:

• Source: Dust, dirt, pollen, rust particles, and other airborne solids drawn in from the atmosphere.
• Forms: Solid particles of varying sizes.   1. Clean Air Act: Battling Contaminants in Pneumatic Components – Fluid Power Journal fluidpowerjournal.com
• Problems:
  • Abrasive Wear: Causes wear and tear on valves, seals, and other components, reducing their lifespan.
  • Clogging and Blockages: Can clog orifices, filters, and other small passages, disrupting system operation.
  • Instrument Malfunction: Can interfere with the operation of sensitive instruments.

4. Microorganisms:

• Source: Bacteria, fungi, and other microorganisms can be present in the intake air or thrive in moist environments within the system.
• Problems:
  • Contamination: Can contaminate processes or products, especially in hygienic or sterile applications.
  • Corrosion: Some microorganisms can contribute to corrosion in the system.
  • Health Hazards: Can pose health risks if inhaled, particularly in breathing air systems.

Additional Contaminants:

• Pipe Scale and Rust: From the internal surfaces of pipes and equipment.
• Process Contaminants: Depending on the environment, the air might also pick up contaminants specific to the vessel or its operations, such as chemical fumes or dust from cargo.

Importance of Removal:

• Equipment Protection: Removing contaminants prevents damage, extends the lifespan of components, and ensures reliable operation.
• Process and Product Quality: Clean air is essential for maintaining product quality and preventing contamination in sensitive processes.
• Safety: Removing contaminants minimizes risks to personnel and the environment, particularly in the case of oil and microorganisms.
• Efficiency: Clean air improves system efficiency by reducing friction, preventing blockages, and allowing optimal performance of control equipment.

In summary: Compressed air for control instrumentation needs to be clean and free from contaminants to ensure the safe, reliable, and efficient operation of pneumatic systems on a vessel. Implementing effective filtration and air treatment measures is crucial to achieve the desired air quality.