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Guide for marines about Boiler, refrigeration and electrical knowledge.

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SUMMARYBOILER1. Energy Audit on Ships: Audit of Marine Boiler2. Energy Conservation in Boilers and Making a Boiler Report 3. What to do When Flame Failure or Fuel Pump Tripping in Marine Auxiliary Boilers Occurs?4. Understanding Boiler Feed Water Contamination5. MAN B&Ws Dual Fuel Marine Engine : A General Overview6. Boiler Mountings: A Comprehensive List7. Important Points for Boiler Cleaning on a Ship8. Boiler Operation Made Easy : Procedure for Starting and Stopping a Boiler9. Blow-Down Procedure for Marine Boilers10. The Science behind Marine Boiler Water Circulation on Ships11. Boiler Starting Failure Troubleshooting12. Procedure for Boiler Gauge Glass Maintenance on a Ship13. Everything You Ever Wanted to Know About Scavenge Fires14. How to Prevent Crankcase Explosion on a Ship?15. What is Turbocharger Surging?16. Everything You Ever Wanted To Know About Crankcase Inspection on a Ship17. What is Steam Hammering in Ships Steam System?REFRIGERATION1. What are the Safety Devices on the Refrigeration System of a Ship?2. Construction and Working of Ships Refrigeration plant3. Guidelines on Quality of Refrigerant Used on Ships4. Understanding Capacity Control in Ships Air Conditioning and Refrigeration System5. How to Charge Refrigeration Plant on Ships?6. Everything You Ever Wanted to Know About Container Refrigeration UnitELECTRICAL1. How is Power Generated and Supplied on a Ship?2. Preferential Trips on Ship : Construction and Working3. Single Phasing in Electrical Motors: Causes, Effects, and Protection Methods4. Construction and Operation of Megger Explained5. Permanent Magnet Moving Coil Instrument (PMMC) Working and Application on Ship6. What are the Main Safety Devices for Main Switch Board on Ship?7. Electrical Safety Device: Air Circuit Breaker (ACB)8. Understanding Rectifier and Rectifier Circuits on Ship9. Amplifier Circuit or Operational Amplifier (op amp) Used on Ship10. Construction and Working of 3 Phase Induction Motor on Ship11. Maintenance of Electrical Relay on Ships Electrical Circuit12. How to Find an Earth Fault On board Ships?13. Why are Transformer and Alternator Ratings in kVA on Ships?14. Reasons for Using High Voltage Systems On board Ships15. How to Install Electronic Circuits on Ship?16. Electric Propulsion System for Ship: Does it have a Future in the Shipping?17. Electrical Propulsion System in Ships18. What is Alternate Marine Power (AMP) or Cold Ironing?19. Important Points to Consider While Carrying out Alternator Maintenance of Ships Generator20. How to Minimize the Risks of an Electrical Shock on a Ship?21. Hazards Related to Electric Cable Insulation in Case of Fire22. Importance of Insulation Resistance in Marine Electrical Systems23. Thermocouples: The Most Common Pyrometer on Ship24. What is Lambda Control in Ships?25. Electric Propulsion System for Ship: Does it have a Future in the Shipping?26. Electrical Propulsion System in Ships

Energy Audit on Ships: Audit of Marine BoilerIn continuation with the last article on energy audit on ships, we discuss the energy audit of the ships boiler. One of the major and important machinery on the ship, a marine boiler comes under special emphasis in an energy audit due to many well marked and potential energy saving areas.A well maintained boiler is not only safe but is also fuel efficient.Basic Steps of Boiler AuditAs discussed earlier, the steps involved in an energy audit are data collection, data analysis and making report. Data Collection: Finding how the ship uses steam, costs of fuel consumed per day and issues by reducing steam consumption for utilities. For example reduction of domestic hot water temperature or reduction of accommodation heating etc. Data Analysis: Identifying measures that would lead to energy conservation. These include measures with no investment, with medium investment and with large investment. Audit Report: The report has to be presented to the owners with the economic viability to enable making decision.Instruments Required for Boiler AuditIn any energy audit the use of proper calibrated instruments is essential. The instruments that are required to carry out an in depth boiler energy audits are as follows: Portable Oscilloscope: Its an all in one tool. It is used for visual display and interpretation of data, trend analysis, data logger, spectrum analyzer and measuring capacitance, resistance, continuity, AC and DC voltage, power measurement for single phase and three phase, total power, apparent power, reactive power, power factor, frequency and current etc. Infrared Remote Thermometer: It is used for temperature measurement and for finding hot spots. Tachometer: For speed measurement of motors and shafts as slippage of belts and lowering of speeds can cause improper air fuel ratio. Master Pressure and Temperature Calibrator: For calibrating the online instruments and sensors in the boiler control panel. Infrared Camera: This camera can take infrared photographs thus indicating trouble areas and hot spots. Flue Gas Analyzer: For analyzing flue gas and measuring concentration of O2, CO2, CO, NOx, and SOx etc. Ultra Sonic Leak Detector: It is used for checking steam traps that are leaking and pin-hole leakages of steam. Other Instruments: The other instruments that are used are digital manometers, calibrated pressure gauges, Multi meter, Clamp ammeter, Contact thermometer, Non contact water flow meter, power analyzer etc.Pre-audit PrecautionsBefore carrying out energy audit on the boiler some precautions must be taken to ensure accuracy and reliability of measurement. The boiler load should be kept constant during the audit. No soot blowing should be done during the audit. No blow down should be done during the audit.Energy Conservation and Optimization opportunitiesDepending on the layout of the ship, make of the boiler, the quality of maintenance and the condition of the boiler there may be some ship specific problems and recommendations; but in addition to these there are some common areas where generally loss of heat occurs and there is scope of energy conservation Excess air in combustion: Specified quantity of air is required as per stoichiometric air fuel ratio for combustion. However as metering in inadequate some extra air is always supplied to avoid incomplete combustion. Excess air lowers efficiency because it does not take part in the combustion and takes away the heat of the furnace. Less air in combustion: If the air is less than the recommended stoichiometric air fuel ratio, incomplete combustion will result. Carbon will not fully burn to carbon-di-oxide but will partially burn to form carbon monoxide. This will cause loss of energy.

Maximum Waste Heat Recovery: The funnel stack temperature must be as low as possible but with sufficient margin to be above the dew point to avoid sulphur corrosion. Generally a funnel temperature of 165 to 195 deg C when using Fuel Oil is considered optimum. In any case when the funnel (Exhaust Stack) temperature is higher than 200 deg C, a more stringent waste heat recovery program should be required. Feed Water Preheating: If the funnel temperature is higher than 200 deg C it can be utilized for feed water preheating, thus increasing the waste heat recovery. It will increase the overall efficiency of the plant Combustion Air Preheating: In case there is still a margin in funnel temperature combustion air preheating may be considered. Blow- Down Optimization: The blow down of the boiler is required for controlling the amount of TDS in the boiler. Blow down must be calculated and done after measuring the TDS amount. Some engineers merrily blow down the boiler excessively without need even when the parameters are in control and it results in loss of precious water and heat. Blow down must be done in response to the conductivity and the pH.In the next article we will look into the areas of energy conservation and optimization opportunities and audit report.

Energy Conservation in Boilers and Making an Audit ReportIn the last article in this series on the energy audit of the ships boiler, we discussed the instruments required for ships audit, pre audit precautions and the energy conservation and optimization opportunities. In this article we discuss the other opportunities for energy conservation and also layout of the final audit report.Read the first two parts of the series here:1. Energy Audit on Ships2. Audit of Marine BoilersEnergy Conservation and Optimization OpportunitiesThe other areas where energy conservation and optimization opportunities exist are as follows:Performance of Heat Transfer Areas: The heat transfer areas of the boiler must be monitored. The soot blowing of the boiler must be done religiously as build up of soot acts like an insulator and reduces the heat transfer rate. That means for generating the same amount of steam more fuel will be needed. The same goes for the buildup of scale in the tubes. The stack temperature must be monitored regularly and any increase in it means that heat recovery is not optimum. If the funnel temperature increases about 40 deg C after last cleaning it indicates that boiler cleaning must be done.Read important points on boiler cleaning here.Heat Loss Due to Inadequate Insulation: The boiler and steam lines along with condensate return to the hot well must be well insulated. Over a period of time insulation is damaged or worn out. Any analysis by an infra red camera or infra red thermometer can identify the hot spots and optimize fuel consumption.Optimum Hot Well temperature: The hot well temperature must be maintained at temperature specified by manufacturers which is generally about 80 to 85 deg C. A lower temperature will cause colder feed water to enter the boiler thus increasing the fuel cost due to loss of sensible heat. An overheated hot well will cause vapor lock in the feed pump and loss of suction.Learn how to troubleshoot marine boiler starting failure here.