Refrigeration PDF

Refrigeration By: 3CL HIANO ISICAN JOVES JC JOVES JM JUBAS KAAMIÑO  What is Refrigeration? Refrigeration systems often referred to as engine cooling systems, are critical for maintaining optimal operating temperatures in ma...

Refrigeration By: 3CL HIANO ISICAN JOVES JC JOVES JM JUBAS KAAMIÑO  What is Refrigeration? Refrigeration systems often referred to as engine cooling systems, are critical for maintaining optimal operating temperatures in marine propulsion engines and auxiliary machinery. These systems ensure that engines operate efficiently, prevent overheating, and maintain the longevity of engine components.  Types of Refrigeration Systems 1.Freshwater Cooling System: Closed Loop: This system circulates a coolant (usually a mixture of water and antifreeze) through the engine block and cylinder head. Heat Exchanger: The heated coolant then passes through a heat exchanger where it transfers heat to seawater before returning to the engine. 2. Seawater Cooling System: Open Loop: Seawater is drawn directly from the ocean and circulated through the engine or a heat exchanger to cool the engine. Heat Transfer: This system uses seawater to absorb heat from the engine coolant, which is then expelled back into the sea. Indirect vs. Direct Cooling: Indirect Cooling: Utilizes a heat exchanger to separate seawater from the engine coolant, minimizing corrosion and fouling risks. Direct Cooling: Involves circulating seawater directly through engine components, which is less common due to potential corrosion issues. Basic Components of a Refrigeration System Compressor: Function: Compresses the refrigerant gas, raising its pressure and temperature. Types: Reciprocating, rotary, screw, and centrifugal compressors. Condenser: Function: Dissipates heat from the refrigerant as it changes from gas to liquid. Types: Air-cooled, water-cooled, and evaporative condensers. Expansion Valve: Function: Reduces the pressure of the refrigerant liquid, allowing it to expand and cool before entering the evaporator. Types: Thermostatic expansion valve (TXV), electronic expansion valve (EEV), and capillary tube. Evaporator: Function: Absorbs heat from the surrounding environment as the refrigerant evaporates from liquid to gas. Types: Direct expansion (DX) evaporators and flooded evaporators.  Refrigeration Cycle Compression: The refrigerant gas is compressed by the compressor, raising its pressure and temperature Condensation: The high-pressure gas flows into the condenser, where it releases heat and condenses into a liquid. Expansion: The liquid refrigerant passes through the expansion valve, dropping in pressure and temperature Evaporation: The low-pressure liquid enters the evaporator, absorbing heat from the surroundings and evaporating back into a gas.  Refrigeration Safety Precautions Personal Protective Equipment (PPE): Always wear appropriate PPE, including gloves, goggles, and protective clothing, to protect against refrigerants and other hazardous materials. Proper Training: Ensure that all personnel are trained in the safe operation and handling of refrigeration systems, including emergency procedures. Ventilation: Operate refrigeration units in well-ventilated areas to prevent the buildup of harmful gases, particularly in enclosed spaces. Leak Detection: Regularly inspect refrigeration systems for leaks. Use leak detection equipment to identify any refrigerant leaks promptly.  Electrical Safety:Ensure that Handling Refrigerants: Follow electrical components are properly installed and maintained. Use proper protocols for the storage appropriate lockout/tagout and handling of refrigerants. Use procedures during maintenance. recovery systems to capture Avoiding Overloading: Do not refrigerants during maintenance or overload refrigeration units beyond disposal. Emergency Procedures:Develop their rated capacity, as this can lead to equipment failure and and communicate clear emergency safety hazards. response procedures in case of Regular Maintenance:Schedule refrigerant leaks or other regular maintenance checks to accidents. Ensure that emergency ensure that all components of the equipment is readily available. refrigeration system are functioning correctly and safely.  Avoidin g Pollutio n in the Marine Refrigerant Management: Environ Use environmentally friendly refrigerants with low global warming potential (GWP) and ozone depletion potential (ODP). Transition away from harmful substances like CFCs and HCFCs. ment Containment Measures: Implement secondary containment measures for refrigeration units to prevent leaks from contaminating marine environments. Regular Inspections: Conduct routine inspections of refrigeration systems on vessels and shore facilities to identify and repair leaks promptly.  Waste Management:Properly manage waste generated from refrigeration systems, including old refrigerants and contaminated oils, by using certified disposal services. Training and Awareness: Educate crew members and staff about the importance of preventing pollution and the proper procedures for handling refrigerants and waste. Emergency Response Plans: Establish emergency response plans that include procedures for dealing with spills or leaks in marine environments. Monitoring Systems:Utilize monitoring systems to detect leaks early and take corrective actions before they result in significant environmental harm. Thank You