The design and operation of an ash treatment system at the. Plant ash extraction, conveyance and storage system this system consists of a bottom ash handling process and a flyash handling process. Opacity spikes can be avoided if the ash system feeds properly. Mechanical boilers, fuel, and ashhandling plant focuses on the design, manufacture and operation of. Metsos mixer conditioners provide uniform wetting of fly ash through an exclusive. Coal and ash handling in thermal power plant mcqs with answers ahsan 071919 good information and some more info like size of coal and equipment descriptions or dictionary of these terms to be included. Aegis has good number of installations for mechanical ash handling systems. The fly ash handling system transports the ashes pneumatically with the compressed air from blower or air compressor through proper. Wet ash handling systems project engineering division. The portion of the ash that escapes up the chimney or stack is. Factors like availability of other resources like water, land etc. A typical pneumatic ash handling system will employ vacuum pneumatic ash collection and ash conveying from several ash pick up stationswith delivery to an ash storage silo for interim holding prior to load out and transport.
Fly ash is captured and removed from the flue gases by economiser, airpreheater and electrostatic precipitator esp. Introduction to commercial building hvac systems and. One of the methods for handling fly ash is wet system in which the ash is mixed with water to form slurry which is. Andritz ash handling systems include conveyors and other equipment necessary for removal of bottom ash and fly ash from the power boiler. Allenshermanhoff advances its technology development in dilutephase transport systems, pressure densephase transport systems and mechanical drag conveyors. The furnace bottom ash and economizer ash is conveyed to dewatering whereas the flyash is conveyed to storage soils. The grab bucket conveyor can be used with crane or tower as. The fly ash system handles the majorlargest fraction of total ash. Ash handling systems may employ different forms of pneumatic ash conveying or mechanical ash conveyors. This conveyor delivers the ash to the ash handling and treatment system described below.
Bottom ash water recirculation system complete with dewatering bins, settling tank and surge tank facility. Metso mechanical ash handling systems 7 metso expect results open the catalog to page 1 integrated systems approach providing a competitive edge through greater capacity and efficiency metsos mechanical ash systems are safe, effective, reliable and performanceproven. Fly ash handling system thru pneumatic vacuum conveying. Ash generated in power plant is about 30 40% of total coal consumption and hence the system is required to handle ash for its proper utilization or disposal. Water used for bottom ash handling is recirculated from the dewatering bins. Draught is defined as the difference between absolute gas pressure at any point in a gas flow passage and the ambient same. The bottom ash quantity is around 20% of the total ash generation and there are mainly two types of bottom ash disposal systems.
System comprises of water impounded refractory lined bottom ash hopper bah of adequate capacity with water seal trough and dip plates. When new power plants were being designed in the 1970s, the state of the art ash handling systems at the time were closed loop water recirculation systems that involved a. Demech provides variety of systems to handle bottom ash or bed ash generated by the solid fuel fired boilers. Capability profile in manufacturing ash handling system narime. Show less modern power station practice, second edition, volume 2. Coal and ash handling in thermal power plant mcqs with answers ch ramakrishna 062216. Maintenance of ash handling plants and pneumatic conveying. Illustration below is sample of working principal on hydraulic ash handling equipment. Introductionin thermal power plants the ash handling practicescoal based solid waste are collected as i.
A single crushing stage can be provided at the extractor discharge to reduce the ash grain size distribution. Types of ash handling system in power plant engineering 1. Fans pull outside air into building for ventilation ventilation includes both outside air and recirculated air requirements are available for minimum outside air, based on occupancy, floor area and number of occupants see the international mechanical code imc chapter 4 or ashrae standard 62. The system has to be selected based on many factors like type of boiler, size of boiler, amount of bottom ash generated, method of final handling etc. Ash conveying systems brochure macawber engineering. Bottom ash conversion options and economics 6 conventional dewatering systems. A mechanical ash handling system is often the best choice for fluidized bed ash where headroom is restricted under. A sh was also awarded the two largest ash handling system contracts ever tendered at that time, both for taiwan power companys taichung station. Introduction to mechanical sludge handling study guide. Fly ash is the major constituent of the ash generated from pulverized and fluidized bed coalfired boilers. Mechanical boilers, fuel, and ashhandling plant focuses on the design, manufacture and operation of boiler units and fueland ashhandling plants. The fly ash gets collected at various points, with most of it in esp hoppers. Coal handling plant in a thermal power generating station. In an industrial context, it has traditionally referred to coal combustion and comprises traces of combustibles embedded in forming clinkers and sticking to hot side walls of a coalburning furnace during its operation.
Systems of mechanical conveyance and elevation are described, comprising ash cars, skip hoists and bucket conveyors. Bottom ash handling system macawber beekay, ash handling. Explain the purpose of the following chemicals used for sludge conditioning. Swapan basu, ajay kumar debnath, in power plant instrumentation and control handbook, 2015. The sfc submerged flight conveyor system for bottom ash handling consists of chainmounted flight bars that continuously travel through a water impounded trough. With modern transmitters and controls, ash handling systems can be better monitored and controlled for switching between feeders and checking for vacuum or pressure leaks in the system. This system requires less power for operation and requires minimummaintenance. Conveyor sdcc is a mechanical ash conveyor that removes wet ash from the water impounded section of the. Ash handling systems hydraulic system pneumatic system mechanical system.
Ash handling plant an overview sciencedirect topics. First of all we will discuss about the dry type bottom ash disposal system. The huge amount of coal is usually supplied through railways. We keep capital investment costs lower and maintenance and operating expenses to a minimum. Ash handling systems may employ pneumatic ash conveying or mechanical ash conveyors.
After sizing, the ash can be dumped onto a mechanical conveyor heading for a storage silo figure 6. Equipment design, industrial communication design, human machine interface programming, onsite support. Metsos mixer conditioners provide uniform wetting of fly ash through an exclusive shaft and paddle. A railway siding line is taken into the power station and the coal is delivered in the storage yard. Coal and ash handling in thermal power plant mcqs with. He is also the current deputy vice president, technical committee for freight pipeline, china mechanical engineering society. Working of ash handling system in thermal power plant. Mechanical ash handling system bevcon wayors bulk made.
In thermal power plants coal is generally used as fuel and hence the ash is produced as the byproduct of combustion. Find details of companies offering ash handling systems at best price. Mechanized ash handling systems developed as the size of coal fired boilers. When the ash storage pond at tennessee valley authoritys tvas kingston fossil plant in harriman, tenn. Sulfuric acid introduction to mechanical sludge handling study guide january 1994 edition. Ash handling systems archives bevcon wayors bulk made. Aegis offers mechanical ash systems that are reliable, cost effective and comes with proven performance with years of experience. Bottom ash is part of the noncombustible residue of combustion in a power plant, boiler, furnace or incinerator. Certain applications which specially require mechanical system, like in case of cfbc afbc type boilers for handling of bed ash collected at furnace bed, macawber beekay offers drag chain conveyor system, followed by pressure pneumatic conveying system as per the clients specific requirement. One important, but often overlooked factor of an efficient ash handling system, is its compatibility with your facility.
Watercooled screws or chain conveyors can be adapted easily for different furnace configurations and for any type of. This is a zero pollution plant for bottom ash removal. List the types of pumps used for mechanical sludge handling. Mechanical ash handling systems mechanical ash handling systems. With options varying from fly ash to bottom ash conveyors, and pneumatic versus mechanical ash handling systems, our experts are ready to. The coal is taken from the unloading site to dead storage by belt conveyors.
The entire water requirement of the ashhandling system may be met with circulating water where the plant does not have a cooling tower facilitythat is, for a oncethrough system in coastal stations using lake or river water, or seawater. Hydraulic ash handling equipment is usually used to convey bottom ash. Esp fly ash handling system for the fly ash handling for power plants, pneumatic conveyor system have worldwidely been appliedesp, bag filter, etc. Hod mechanical at godavari institute of engineering and technology. Pdf troubleshooting in dry fly ash conveying systems. And a case study was presented in 20, to investigate the benefits and drawbacks in the use of simulation in. With over 100 installations worldwide, the sfc system has proven to be the industry leader for performance and reliability. Fly ash handling wherever products are burned it is necessary to have an energy efficient ash handling system, especially in a power station environment where large quantities of pulverized fuel ash pfa are created. Ash handling system in thermal power plant ash handling. The coal is unloaded from the point of delivery by means of wagon tippler. A typical ash handling system may employ vacuum pneumatic ash collection with ash conveying from several ash pick up stations and resulting in delivery to an ash storage silo for interim holding prior to load out for disposal or reuse. Ash handling system power plant engineering amit mak. There are three general methods of conveyance in use. Pneumatic conveying systems are used to handle dry fly ash.
Industries are of three types, classified as small scale. The equipment should be corrosion and wear resistant. Modern power station practice, second edition, volume 2. This volume is beneficial to operators and manufacturers of boilers and fueland ashhandling plants. Macawber beekays product profile includes jet pumping system for intermittent removal of bottom ash collected at furnace bottom of pf type boilers. Such ash can be a considerable environmental nuisance as well as being awkward to handle due to its abrasiveness and hydroscopic characteristics.
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