Occupational Safety and Hazard Assessment in Steam Boilers

By Hisham Hashim

The National Board Inspection Code (NBIC) and Factories and Machinery Act (Malaysia) recognized the potential hazards of steam boilers and established various codes and regulations pertaining to controlling the hazards and minimizing risks. Each year, the authorized inspectors inspect fireside and waterside for defects, scaling, and corrosion. Each year, all essential valves and fittings are dismantled for inspection. Plate thickness is checked, boiler water analysis results are reviewed, and indeed, the authority enforces rigorous maintenance on steam boilers but still, various boiler accidents happened. One might wonder why. The reason lies in one salient factor: human error is the leading cause of boiler accidents. One statistic indicated that 83% of boiler accidents were a direct result of human errors due to lack of knowledge and awareness. Although inspection has become stricter, the local authority does not cover inspection on boiler safety controls and all routine or non-routine activities. OSHA can only provide guidelines for safety in the workplace but ensuring the implementations is beyond their scopes.

The fundamental cause of hazards in an organization is organizational inadequacies. The inadequacies can be related to safety controls, safe operating procedures (SOP), hazard and risk assessment and controls, and training or awareness. With inadequacies, employees usually do not realize the hazards and consequences of their actions. Therefore, to minimize or eliminate risks exposed to all employees, contractors, and visitors in their activities, an organization should establish occupational health and safety (OHS) management system. Only through OHS that hazards can be recognized, and safety and health risks can be assessed and properly addressed. The management can set objectives, provide suitable controls, provide sets of procedures (SOP's), organize training programs, and establish safety performance evaluation.

Boilers have many potential hazards that must be controlled by safety devices and safe work practice. Before identifying the hazards, one must understand the meaning of hazards. In this context, hazard is defined as "a source or situation with a potential for harm in terms of injury or ill health, damage to property, or a combination of these". To begin identifying hazards, the management must know what activities are involved. Activities can be divided into two categories which are routine and non-routine. Routine activities include daily operation, chemical preparation, and fuel storage and handling, while non-routine activities include boiler overhaul, confined space entry, and emergency response. The first stage in hazard identification is a selection of job to be analyzed.

The management is to select the key activities first, such as daily operation and chemical preparation. In the second stage, OHS management is to break the activities into logical steps. The logical steps must be unique to the activities, and trivia activities such as switching on lights should be avoided. Examples are taking data from various meters during operation, or pouring boiler chemicals into a jar. In the third stage, the management is to identify hazards and determine the corresponding risks in each step. When preparing boiler chemicals, the boiler operators are exposed to corrosive liquid spill and acid gas release. Risk is the consequence, and in this case, the risks are eyes lesion and pain, burn injury, or cancer if handling hydrazine. High noise level which is above 85 dBA is an example of hazard in daily operation and the risk is obvious, which is deafness. In stage four, the management is to develop risk elimination or reduction measures.

For high noise level, risk elimination or reduction measures would require path noise control such as acoustic insulation (lining) or acoustic partition, enclosure for the noise-radiating source, increase pipe size to reduce steam turbulence, or install noise diffuser. The best approach is to control noise at source, such as installing silencer, changing equipment for example changing normal pressure reducing valve (PRV) to low-noise PRV. Other risk controls for high noise level would be wearing personal protective equipment (PPE) or reducing exposure time. The most common hazard for boiler operation is low water and the risk could be a permanent damage to the boiler or explosion. Modern boilers are usually equipped with automatic level controllers, low water level burner interlocks, low water alarm, and regular checking of gage glasses by the boiler operators. All these are risk controls by safety devices. Working in confined space is a non-routine activity, the hazard associated with it is physical injuries or fatalities due to asphyxia or poisonous gas, and the current risk control is following the guidelines of confined space entry, which shall not be covered here.

In pouring the chemical into a jar, the hazard is chemical splashes to eyes, and the risk is eye lesion and injury. From this, the risk control would be wearing safety goggles. Another example of daily operation is blowing down. Blowdown can cause spillage of hot water, which is the hazard, and may scald boiler operators, which is the risk. The example of risk control is blowing down into the blowdown chamber instead of directly into the atmosphere thereby reducing potential spillage of hot water to the surrounding.

In the final stage, after job safety analysis is completed for each activity, the activities, hazards and risks, and the corresponding risk controls should be documented for reference. Based on that, safe operation procedures can be established to ensure risks at the workplace can be eliminated or minimized. Training must be conducted by the competent person-in-charge to all boiler operators to explain in detail the hazards, risks, controls, procedures and responsibility as well as accountability.

For any organization which does not have structured OHS management system, I would recommend OHSAS 18001 or MS 1722 certification. OHSAS 18001 or MS 1722 provides a set of procedures and tools to promote continual improvement through hazard identification, risk assessment, and control of risk in a very systematic way. Apart from these benefits, I noticed with the implementation of OHSAS 18001 standards, the management and employees in my organization have improved significantly in their understanding of health and safety legislation as well as the ability to demonstrate compliance.

Hisham Hashim is a proud author of 101 Q&A Practical Knowledge of Steam Boilers e-book and writes articles on various subjects in steam boilers, safety, and environment. He has strong hands-on experience in preparation, development, and implementation of ISO 9001, ISO 14001, and OHSAS 18001. He also participates actively in HSE audits as the lead auditor, and proposes corrective actions on noncomformance. To learn more about all aspects of steam boilers, from operation, maintenance, boiler water treatment, to boilers codes and safety, visit his website at [http://www.boiler-ebook.com] for further information.

Article Source: https://EzineArticles.com/expert/Hisham_Hashim/499689

Boiler Service For Boiler Safety

By Mark Andrew Woodcock 

A boiler is a closed vessel in which water or other liquids are heated. When most people hear 'boiler' they think of their hot water tank at home which heats their radiators and shower. In the past, boilers have been associated with injuries and even deaths due to a number of factors which meant they were not 100% safe for use. Today's boilers are technologically sound and any accidents that happen are rare and could often have been prevented had a boiler service being carried out.

Inside a boiler there is pressurized steam which is created as the water heats up. If there is any defects in your boiler this can lead to serious injuries, the most common happening to be burns. Faults in the boilers include poorly welded seams and hinges which can come open if the pressure inside the cylinder gets too high. If the boiler is old it might be made out of thin or brittle metal which can rupture after heavy usage or if the temperature gets too hot. A regular boiler service will help you to avoid accidents such as these, and will keep your hot water system in tip-top condition.

Another safety issue that boilers can present is running dry. If there is a leak in the system somewhere or the boiler is allowed to empty of all of its liquid, the metal shell is exposed to intense heat. The next time any water hits the shell an explosion will occur and the whole boiler could blow up.

If you have a boiler in your house that is out of warranty, it is unlikely that the provider will be held accountable should something go wrong. Spending a few pounds a year on an annual boiler check-up could save you hundreds of pounds should something serious go wrong, and could end up saving your life if a defect is found.

In November 2007 Christine Goodall from Gloucestershire died along with her pet dog when a boiler behind her fireplace exploded. The water inside had expanded as the tank got hotter and caused the metal to rupture, which led to Mrs Goodall's death.

The boilerguide, a leading online resource for homeowners and industry workers recently reported that 1 in 5 home owners are not aware of when their boiler should be serviced. This could leave many houses without central heating in the winter months and make your living condition extremely uncomfortable.

Author Mark Woodcock is a Webmaster of a wide variety of online speciality shops including a very popular site offering a Boiler Service. Visit http://www.eagaheat.com today.

Article Source: https://EzineArticles.com/expert/Mark_Andrew_Woodcock/337682

4 Dangers Of Using A Faulty Boiler

By Elen Moja  

A machine such as a boiler can be faulty, caused by several factors including the operation, design, structure, and its maintenance. These machines can sometimes become faulty from years of involuntary neglect or in this case, ignoring boiler repair. When it comes to these types of failures, there is no potentially dangerous equipment operating in an industrial manufacturing facility than power generating equipment. The boiler is known to be the largest and most expensive equipment but also the most dangerous, if mishandled. Here are some of these dangers.

· Fuel explosions

This has to be the most dangerous situations you may face when using a faulty boiler. The effect is the same as that of a fuel explosion in an oven! The boiler could have operational problems that occur either while using it or during manufacturing. To eliminate such occurrences, always buy a steam boiler from a legitimate manufacturer. If properly operated and maintained, the possibility of a fuel explosion is virtually reduced.

· Inadequate water blow down

For a boiler to last long and perform its blow down practices, high quality feed-water is required. The unwanted solids in the boiler water are reduced by the blow down system which should properly run at all times. Should the boiler exceed the limits, potential problems such as corrosion, scale and sludge formation, moisture carry over due to foaming, and poor steam drum performance will occur.

· Poor feed water quality

Feed water should always be treated to protect the boiler from corrosion and buildup of solid deposits on the tubes. Water in the boiler is vaporized to steam and leaves the solids in form of scale the areas where there is a high rate of heat transfer. This can result to an insulating layer that prevents the water to eliminate heat from the surface of the tube. If it worsens with time, the tubes are eventually going to overheat and cause permanent damage. To prevent deposits on tubes, maintain low levels of solids. The higher the pressure and temperature of the boiler, the more feed-water treatment is encouraged.

· Low-water incidence

Boilers have furnace temperatures exceeding 1800 F. Therefore, you can imagine the damage that would be caused if near low water conditions exist. The main reason boilers can withstand these extreme temperatures is the presence of water in all the boiler tubes when a fire is present at all times. In a matter of minutes, constant firing during a low water condition will literally melt the steel boiler tubes.

We provide the best info about boiler repair London [http://www.northlondonplumbers.co.uk/boiler-maintenance-north-london]. For further details please visit the provided link.

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Is a Steam Boiler a Time Bomb?

By Hisham Hashim 

Before answering the question, let us examine the following scenarios: On Dec 29, 2009, a boiler exploded at a palm oil mill in Sabah, Malaysia, killing one boilerman and injured many others. On September 24, 2010, nine people were killed and four others injured when a boiler exploded in an aluminum plant in Xiaoyi City, China, and on Feb 22, 2011 in Talkatora Industrial Estate in Uttar Pradesh, India, three persons were killed and six received serious burn injuries following a huge boiler explosion in Kiran Plywood Factory.

Based on those incidents, despite having various protections and inspections by local jurisdictions, we can conclude that explosion is actually not very rare in modern boilers. It happened almost every year although today, the casualty did not exceed 20 people per year. The good news about boiler explosion is that it can be prevented. The bad news however, some personnel are not aware of the mechanism of boiler explosion and tend to stick to the routine they have been practicing for years, and thus accident happens. So the answer is, yes and no.

Investigations after investigations were made and human errors seem to be the main cause for boiler explosion. Other causes are inadequate boiler operating procedure, improper boiler maintenance, or inoperative boiler controls and safety devices. Therefore, special considerations must be made on standard operator training.

The topic of boiler explosion is too broad to be covered in a short article; therefore, I shall only discuss the causes of fireside explosion, since furnace explosion is more common than waterside explosion. First of all, what is fireside explosion? Well, in a fireside explosion, an accumulated combustible mixture ignites almost simultaneously, creating a force which exceeds the yield strength of the boiler furnace, casing or uptake, causing catastrophic structural damage. The sudden load explosion in the boiler furnace can be heard miles away.

The principal cause of furnace explosion for oil-firing boiler is the accumulation of unburned fuel in the furnace due to incomplete or non-ignition. The accumulated oil on the hot furnace floor begins to volatize and releases its combustible gases when the operator initiates another trial for ignition. When the mixture of unburned fuel with air is in explosive proportion, explosion will occur. Explosive proportion is where the lower explosive limit (LEL) of diesel fuel marine (DFM) is 0.6% by volume vapor to oxygen. Once the LEL is reached, explosion may occur. Maximum explosion normally occurs at 2.0% by volume DFM vapor to oxygen.

There are many ways the oil may enter the furnace in an unburned state. Poor atomization can cause discharge of unburned oil into the furnace. There are three ways of atomizing fuel, which are forcing under pressure of 5 to 15 bars, steam atomizing, ranging from 5 bars to 10 bars of steam, and mechanical atomization (rotary cup atomizers) with a rotary cup rotates at 8,000 rpm. Obviously, if the atomizing pressure is too low, oil cannot atomize properly and much oil will drop on the furnace floor in an unburned state. Sometimes atomizing steam can be wet due to high condensate which is often due to poorly insulated steam line or malfunctioned steam traps, which can result in loss of atomization.

Most importantly, atomization is affected by the viscosity of the oil which in turn affected by the temperature. To prevent this, the oil tips must be clean, the oil temperature must be correct to keep the oil at oil firing viscosity of 200 to 220 SSU (Saybolt Seconds Universal), and the atomizing steam (or air) pressure and fuel oil pressure must be properly adjusted. This means that the oil must be heated up to 60oC for light oil and as high as 95oC for heavy oil.

Fuel inlet valve can also be a problem. Fuel can also enter the furnace through leaky fuel inlet valves on idle burners. Sometimes, the fuel inlet valve cannot secure fuel supply to atomizers promptly when fires are extinguished or there is a slight delay in fuel shut off if the flame extinguished unexpectedly.

During starting up, sometimes difficulty is experienced in establishing ignition due to failure of photocell or flame scanner (or other mechanical problems) that can prompt the boilermen to attempt starting up the boiler for several times, which resulted in pool of unburned fuel to be accumulated after each trial.

Failure to purge furnace properly, including furnace, boiler and uptake areas can also cause boiler explosion. During boiler startup, purging sequence is required to drive out all combustible and explosive gas from the furnace through the uptake before ignition. Purging sequence must be sufficient. As a rule of thumb, an ideal purging should give five changes of volume. For a large boiler, normal set time would be 20 minutes while for a medium or smaller, a shorter time may be required, and the air flow must be low, which is only 25% of the normal full-load air. Purge air requirement is normally 4 SCFM for light fuel or 15 SFCM for heavy fuel. A word of caution, never bypass the purging sequence by all means.

Learn how flame impingement and soot blowing can contribute to fireside explosion. Besides overpressure, learn how low water and other causes can cause waterside explosion and implosion. And most importantly, know the ways to prevent boiler explosion from me in detail.

My name is Hisham Hashim, a competent steam engineer, and I have vast experiences working with power boilers including solid fuel and natural gas boilers. I have successfully trained many engineers and boilermen to obtain their competency certifications. Whether you are sitting for your First Grade, Second Grade, or even Boilerman Certificate of Competency, whether this is your first try or your third try and no matter which country's exam you're taking, I have the tools and information you require to pass your boiler licensing examination with flying colors. For further information, visit [http://www.boiler-ebook.com]

Article Source: https://EzineArticles.com/expert/Hisham_Hashim/499689

Boiler Explosions

By Michael Enfield 

A boiler, also known as a steam generator, is a closed compartment in which water, or sometimes another fluid, is heated. The heat is used to produce steam, which in turn is used to power an engine or for heating applications. Historically, boilers have been known to cause devastating explosions, and although modern boilers are designed and assembled with caution regarding worker safety, sadly, catastrophic explosions may still occur if a boiler fails.

Boiler Failure

Older-model boilers often have a lack of structural integrity that can cause explosions. If a boiler is made of a brittle, thin metal shell, it can rupture. If seams are poorly riveted or welded, they may come apart. If a tube collapses or becomes dislodged, dangerous steam and smoke can spray out and injure anyone in the near vicinity. Or, if the water drains from a boiler and new water is added, the new water may evaporate on contact with the hot shell and cause and explosion. Failures in large boilers that offer a large amount of energy to operate factories can destroy entire buildings.

General reasons for boiler failure include:

• An excess of pressure within the boiler
• A lack of water inside the boiler, causing the vessel to overheat
• Defective construction or lack of maintenance, causing pressure vessel failure

Why Boilers are Dangerous

Many people underestimate the dangers of boilers, thinking that water and steam can only do so much damage. However, the boiling water inside of a boiler has enough energy to power entire engines, machines, and even large factories. A failed boiler can cause devastating injuries, loss of life, and loss of property.

Some basic boilers contain pressurized water held at a temperature of about 300 degrees Fahrenheit. If somehow the boiler looses pressure suddenly, all of the water would instantly evaporate into steam. Water in its gaseous state takes up around 1,600 times as much space as water in liquid form. If a leak occurs in a boiler, this evaporation and expansion of water into steam can take place less than one second, producing a giant explosion.

Modern boilers contain many safety features to reduce the risk of explosions, including:

• Safety valves, which can be adjusted to release steam before a buildup of pressure
• Fusible plugs, which may overheat, melt, and produce a whistling noise to warn workers when a problem occurs
• Ties, also known as stays, which attach the boiler casing to its exterior compartment and prevent warping.

To learn more about boiler explosions and injuries, visit the Explosion Victims Resource Center [http://www.explosionvictimresourcecenter.org/].

Michael Enfield

Article Source: https://EzineArticles.com/expert/Michael_Enfield/584120

Using Ball Mills in the Energy Industry

By Andrey Sysoev  

Experimental studies on coals of different metamorphic grades and various fractional states were conducted in 2000 by the Institute of Thermal Physics of the Russian Academy of Sciences, at experimental thermal energy facilities. These showed that fine-ground coal, milled to a particle size of 15-30 microns, develops a highly reactive property that is analogous to fuel oil - to which it can become an alternative. The experimental facility was rated at up to 1000 kW, and equipped for use with ultra-fine ground coal (produced with an ultra-fine ball mill); burning (pre-furnace and furnace equipment); a plasma system and gas starter for ignition and supplementary firing; combustion control (an automated post for combustion control) and cleaning (a vortex scrubber). The results produced in these experiments can be used to establish the parameters needed in technological facilities for ignition systems and supplementary burning using coal-dust boilers - a replacement fuel for gas and fuel-oil boilers.

The conclusions from these theoretical and experimental studies pointed to the technical and economic viability of using ultra-fine ground coal as a new oil-free technology for the ignition and stabilisation of combustion in coil-fired boilers at power plants, in addition to the ability to replace liquid fuels in boilers.

The primary technological facilities for making use of this new technology are: equipment for ultra-fine milling (ball mills), and the supplementary equipment for supplying and combustion of coal. Technical designs for the supplementary equipment have been developed, which are essential for wheeling-out the new technology (muffle furnace apparatus, input nozzles for the coal dust, accelerating devices for igniting the primary fuel mixtures, feeders for fuel discharge, hoppers for storage, and so forth). Factories able to manufacture the new supplementary equipment already exist in Russia. The last-mentioned also produces milling equipment, and specifically ball mills for ultra-fine milling processes.

This new technology is low-cost, with a short return-on-investment cycle which will hit break-even in no more than 2 to 3 years. The additional financing costs are in producing the ultra-fine ground coal (the purchase of ball mill machinery) - the additional machinery also has a short investment payback cycle due to the economics of the fuel supply industry.

The new Plasma-fuel technology has now passed the final stages of certification - for pilot industrial use. This allows assessment of the risks of the new technology - and if required, it can be further honed to optimise its operation prior to finalising the business case which can be put to potential investors.

Converting oil-fired boilers to run on ultra-fine ground coal

The primary task is moving to rejecting the use of fuel oil by the facility in future. Of course, in places where it is available, it makes sense to change to using natural gas. However, where this is not an available option, then such facilities can be converted to run on ultra-fine ground coal. The economic result of making the change from fuel oil to ultra-fine ground coal will be in the greatly reduced cost of fuel. Over and above this, there is an environmental gain to be made - since there will be a marked reduction in the emission of sulphurous oxides into the atmosphere. This has a further economic benefit, in terms of decreased payments to be made for such emissions.

When making the changeover to using ultra-fine coal, the issue of disposal of the ash waste which it produces needs to be addressed. For facilities currently using fuel oil, this can be problematic. In the first instance, this issue could be resolved by making agreements to remove the ash and slag waste from the boiler room to nearby ash dumps or industrial sites. This process could lead to a loss of some of the cost benefits of making the changeover. But in a more positive light, the ash and slag waste can be recycled as a component in the manufacture of construction industry materials, mineral components, and similar by-products. Installing a production line for the recycling of slag and ash is not only a responsible way of negating environmental pollution - but can similarly cull in economic benefits.

This means that the issue of converting oil-fired power stations to run on ultra-fine ground coal can be easily resolved both technically and administratively. Each individual case for conversion should properly be put through a business plan, including a technical survey of the boiler equipment, and the prevailing economic situation.

Evaluating the efficiency

Energy efficiency can be determined by making a comparison with the costs of fuel oil operation (i.e. the current costs), against the projected costs of transferring the facility's operation to ultra-fine coal (the current costs, plus the cost of additional equipment). To make these estimates for the current costs, it follows that the costs of the current in-purchasing of fuel oil should be compared against the costs of purchasing coal, plus the additional electricity costs incurred in the grinding process. Particularly concerned with this latter cost, it pays to consider the choice of grinding machinery in the light of its electrical consumption costs. It makes obvious sense to purchase machinery with the lowest energy operating costs. Furthermore, when weighing up the decision to switch from fuel oil to ultra-fine coal, the operation of installing the additional equipment needed for ignition of the ultra-fine coal must be carefully considered.

Essential equipment:

The ball mill for grinding ultra-fine coal is essential. This kind of coal-grinding apparatus to create combustible fuel is traditionally divided into several categories. Quiet-Operation Slow Ball Mills operate with a rotation speed of 16-23 revs per minute. Fast-Action Tangential Mallet Mills have an operational speed of 590 to 980 revs per minute; and there are also Medium Roller Mills which rotate at 40 to 78 revs per minute. The table of ultra-fine coal dust obtained is below, depending upon the type of machinery chosen.

• Ball drum mills are used for grinding anthracite and bituminous coal with a milling operational range of ≤ 1.1 and low volatility required fine grinding (6... 7 %). If the raw source material to be milled includes some presence of pyrite sulfur fuel ( up to SP > 6 % ) then only ball mills can be used.
• Hammer mills are used for brown and black coal of relatively high volatility (Vg > 30 % ).
• Medium Roller Mills are used for grinding coals with a milling operational range of at least 1.1 Wp and humidity of no more than 16 %, with an ash content of no more than Ar 30 %

Additional Equipment required for producing the ultra-fine coal fuel:

• crusher
• crushed coal bunker
• coal feeder
• high-pressure fan
• coil-dust burner
• muffle furnace extension
• blowing fan
• milling shelf
• cyclone dust collector

The primary rationale for undertaking the technical changeover is to replace expensive and increasingly-scarce fuel oil - traditionally used for the ignition and stabilisation of combustion in coal-fired thermal plant boilers - and also to replace liquid fuel oil in boilers. Issues of economic efficiency in tandem with environmental responsibility should underlie decisions for making the changeover. Coal combustion can make up part or the whole of the combustion process in combination with other resources, and offers enhanced productivity for boiler equipment along with reductions in fuel consumption when producing energy through combustion processes, along with an improved level of cleanliness and purification in the resulting flue gases.

The Strommashina plant in Samara produces and installs all of the above-mentioned and recommended kinds of ballmill and mill machinery - as well as dryers, crushers, feeders, cyclones and separators. Strommashina has been producing reliable power generating machinery since 1942. Over that time, the corporation has been continuously honing its technology and quality control - thus resulting in Strommashina's appearance on the world market for industrial equipment. The company's specialist staff are on hand to offer their advice in designing and purchasing equipment, as well as providing expert technical advice and support at every stage of the design, set-up, inception and operation of the equipment they produce.

Strommashina's Strong Points

• Geographical convenience - Samara is a big transportation hub located in the middle of Eurasia. The railway sidings are part of Strommashina's Plant infrastructure. River port accessibility provides ease of connectivity to Europe and Central Asia.
• Installation supervision (comprehensive control over how equipment and production lines are installed and commissioned)
• 1 + year warranty

Have a question or need a quote? Please, feel free to Contact us!

Strommashina Corp.
22 Partsyezda st., 10a, Samara, Samara Oblast, Russia, 443022

Tel: +7 (846) 374-1741

Article Source: http://EzineArticles.com/expert/Andrey_Sysoev/2330153

Coal Power Plant

By Id Weha 

Coal power plant is a power plant that uses coal as fuel. The working principle of coal power plant is a coal-yard of Coal will be transferred by using a belt conveyor to the coal bunker. Coal from the coal bunkers will be destroyed in the Pulverizer so it becomes very soft powder. From Pulverizer then circulate to the burner on the boiler, in this area will be combustion burner and will heat the tubes in the boiler. Due to this heating water in a tube going up above the boiling point to produce steam, then steam is used to drive turbines that function to produce mechanical energy to drive the generator. In this generator of electrical energy generated by the principle of changes in the lines of magnetic force.

For the water-steam cycle usually use a closed cycle in which water used to produce steam main is the same water that the Circulate and continue to be used for the next cycle, it is only necessary to add water (makeup water) when the volume of water is less than set point her.

Water used is treated seawater using MED (Multi Effect Desalination) into fresh water. Furthermore, the water is purified through a process of filtration and ion exchange system through Water Treatment Plant equipment. Pure water that has been processed through the Water Treatment Plant is channeled into the water charging system boilers. The process begins with the initial combustion in the boiler where to start burning fuel oil used as fuel, but when the load has reached 30% then the furnace is hot enough and began to include coal as fuel until the load reaches 100%. After the temperature in the boiler has sufficient fuel oil to be replaced with coal.

Water will be pumped using a Boiler Feed Pump (BFP) through Economizer then subsequently taken to the Steam Drum. In the steam drum is separated between the steam and water. Fluid which still has a liquid phase is circulated through Wall Tube to be heated which is then channeled back to the Steam Drum. Vapor phase in Steam Drum channeled toward primary superheater and then proceed to the Platen superheater and Secondary superheater. After going through the superheater, the superheat steam flow to the High Pressure Turbine (HP Turbine) to be expanded. After experiencing an expansion in the turbine the steam pressure and temperature will decrease the output of the turbine so it needs to reheat. Performed in Reheater reheating.

From Reheater, steam will be entering the Intermediate Pressure Turbine (Turbine IP) and then proceed to the Low Pressure Turbine (Turbine LP). At Turbine energy change of thermal energy that brought steam into mechanical energy. Mechanical energy in the form of round rotor is used to drive turbine generators. In the generator mechanical energy is converted into electrical energy.

Steam coming out of the LP turbine and then condensed in the condenser with seawater as cooling water medium. Therefore, the vapor condenses on the output conditioning condenser in order fluid material unless the state of saturated liquid minimal. Charging system of water into the boiler from the condenser is pumped by Condensate Pump streamed to Deaerator, where water that has been entered will first be passed Condensate Polishing Plant and heating low pressure Low Pressure Heater channeled toward Deaerator.

In Deaerator separated O2 and other non-condensable Gases. Water that has undergone a process deaerasi is accommodated in a Storage Tank to be channeled into the boilers at the next cycle by using the Boiler Feed Pump.

Water is pumped to the boiler filler Boiler Feed Pump for the first flow is passed High Pressure Heater and economizer to heat the water entering the boiler at or commonly known as preheater before entering the steam drum. Deaerator and high pressure heating gets heat from steam turbines or retrieval (Extraction Steam Turbine). As for the economizer is getting heat from boiler flue gas remaining after heating the superheater. After water vapor from the economizer and water will be accommodated in the steam drum.

This cycle will always be repeated endlessly (closed cycle), although repetitive but still need the addition of more water from the Water Treatment Plant to the condenser for the looping of water due to evaporation of water leaks and steam heat in the heating process or also the reduction of water by blowdown system.

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Article Source: http://EzineArticles.com/expert/Id_Weha/1214819