A short comparison of the dry system with the wet system is presented in table ii10. Rendition of a ucc nuveyor system for a utility boiler, including gravity discharge ash pit hopper. With the increased use of bottom ash, there is a greater interest in dry cooling and dry removal of ash from the bottom of boilers. United conveyor corporation ucc is a global leader in ash handling solutions for the power generation industry and a preferred supplier for dry sorbent injection, activated carbon injection and reagent handling. The system comprises of dry type bottom ash hopper of adequate capacity with water seal trough and dip plates, allowing free expansion of the furnace without any air ingress. This results in a lower cost, because there is no need to dispose of or treat the water that is used in a wet process plus there are lower emissions and heat energy. The remaining ash will be stabilized to support the cover system. A dry ash handling system with conditioning upon discharge was first used by kamengo in 2005 for a pulp and paper mill in rothschild, wisconsin. Bottom ash cdr system with remote sfcs 100% redundancy. The dry bottom ash handling system according to claim 9 wherein the means for disposal of said ash is a vehicle mounted tank. The vax system is the most costeffective and rugged dry bottom ash handling system available. Ash handling system power plant engineering amit mak.
As part of our complete environmental technologies line, we continue to provide a variety of ash and material handling solutions, from completely dry bottom ash handling to fly ash and petroleum coke processing. The hot ash from the furnace gets quenched as it enters into the water minimizing the clinker. Ucc develops dry bottom ash conveying withnuveyor pneumatic ash conveying systems, ggyravity dischargg pe ash pit hoppers. Innovations in bottom ash conversion technologies burns. Bottom ash, including partially burned embers, fall out of the combustor 12 into an ash burning and.
With options varying from fly ash to bottom ash conveyors, and pneumatic versus mechanical ash handling systems, our experts are ready to help evaluate which application is best for your plant. The fly ash gets collected at various points, with most of it in esp hoppers. To accomplish this, a primary crusher is used to initially size the material as it falls off the extractor belt, then a secondary crusher further reduces the particle size of the bottom ash to meet the requirements of the pneumatic handling system. Explaining ash handling systems for biomass to energy boilers. Until a decade ago, removal of bottom ash in a dry state from a large utility size boiler was considered impractical. Fly ash is the major constituent of the ash generated from pulverized and fluidized bed coalfired boilers. Very finely sized fly ash often accounts for the major portion of the material conveyed in an ash handling system. First of all we will discuss about the dry type bottom ash disposal system. Dry bottom ash handling system cuts plant carbon emissions. Types of ash handling system in power plant engineering 1. Bottom ash conversion options and economics 3 wet bottom ash ba material handling systems and surface impoundments are presently regarded as the industry standard and are certainly the most commonly used method in the coal fired power industry around the world today. Coarse ash material such as bottom ash is most often crushed in clinker grinders crushers prior to being transported in the ash conveyor system.
Bottom ash is handled using hydraulic system, submerged scraper conveyor system and dry bottom ash system. One important, but often overlooked factor of an efficient ash handling system, is its compatibility with your facility. A dry bottom ash handling system is probably more environmentally friendly and economic from a capital cost as well as maintenance cost point of view. Dry ash handling system westinghouse electric corp. Dry bottom ash handling system florida power corporation. They range in size from 300 cubic feet to 17,500 cubic feet, and are designed to work seamlessly with ash handling systems like the ones we have discussed. Watercooled screws or chain conveyors can be adapted easily for different furnace configurations and for any type of solid fuel being combusted. The vacuum conveying system operates so as to allow sequential ash discharge from ash hoppers into conveying stream which is in continuous operation. An alternative solution to conventional wet bottom ash handling systems is the mac system magaldi ash cooler a fullydry technology. Wet ash handling systems project engineering division.
Factors like availability of other resources like water, land etc. Inventory is maintained for a wide range of critical parts, which means fast delivery of the parts you need most. These systems frequently continue to burn bottom ash, using ambient air instead of water during the extraction and cooling phases. Plants that are considering a wet to dry bottom ash conversion or ash pond elimination have the following options. Worldwide, the wet bottom ash handling is still the predominant procedure but growing environmental awareness in industrialised countries and increasing water shortage at many power plant sites are causing more and more a shift to the dry technique. As part of our complete environmental technologies line, we continue to provide a variety of ash and material handling solutions, from completely dry bottom ash handling to. These dbahs researched, designed, and developed in conjunction with a chinese supplier, crush, remove, and air cool hot ash without the need to water quench resulting in a dry product that can be transported via truck, and potentia lly used in road base. These dbahs researched, designed, and developed in conjunction with a chinese supplier, crush, remove, and air cool hot ash without the need to water quench resulting in a dry product that can be.
Expression of interest eoi for technology tieup for dry bottom ash. Ash handling systems ducon supplies both wet and dry type ash systems for power plants. Wet ash handling system the free falling ash from boiler furnace is collected and stored in a w shaped water impounded bottom ash hopper provided below boiler furnace for its periodic removal twice in a shift of eight 8 hours per unit. Pneumatic technologies call for existing bottom ash hoppers to be replaced with new dry hoppers, as well as a vacuum conveying system. Ash collected in economiser, primary air heater and secondary air heater hoppers drops continuously through suitable vertical pipe. Vacuum system envisages conveying of dry fly ash from ash hoppers by vacuum pumps and collection in ish. Maintenance of ash handling plants and pneumatic conveying. Magaldi dry bottom ash handling in pcf power plants duration. For projects demanding continuous removal of bottom ash collected at furnace bottom, macawber beekay offers submerged scraper chain conveyor sscc system. The vax vibratory ash extractor is the latest evolution in dry bottom ash handling technology which delivers superior heat recovery, lower installed cost, higher reliability and less maintenance compared with conventional moving belt designs. The final component of a highquality ash handling system is the ash storage silo.
A dry bottom ashhandling system is probably more environmentally friendly and economic from a capital cost as well as maintenance cost point of view. Ash handling systems may employ different forms of pneumatic ash conveying or mechanical ash conveyors. 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. A simplified schematic of a hydraulic system is shown in fig. Synergy engaged hrl to design, construct, import, install, and commission three dry bottom ash handling systems dbahs on units 5, 7, and 8. Each vacuum pump, dedicated to a stream, can convey both coarse and fine ash. Ash conveying systems brochure macawber engineering. Bottom ash wtd conversion alternatives presentation prepared for. The first type of dry bottom ash system consists of a storage hopper where the.
Wet ash system is can be utilized for bottom ash handling with water impounded hopper and jet pumps for intermittent removal. Introductionin thermal power plants the ash handling practicescoal based solid waste are collected as i. A new 800 mw coalfired plant in germany has installed an eco friendly dry bottom ash handling system. The bottom ash quantity is around 20% of the total ash generation and there are mainly two types of bottom ash disposal systems. A recirculation system converts a wet sluice system into a dry ash system. The material handling systems include coal handling system and ash handling system for thermal power plants and raw material handling. Water impounded bottom ash hoppers, located under the boiler throat are used to.
Bottom ash is most often conveyed in a hydraulic system in which the ash is entrained in a highflow, circulating water system and delivered to an ash pond or to dewatering storage bins. Demech provides variety of systems to handle bottom ash or bed ash generated by the solid fuel fired boilers. Dry bottom ash handling in pcf power plants youtube. From this year the name of the company changed to eroterv. This demand is basically the result of the intention. These technologies offer environmentally sound solutions to address wet fgd scrubber wastewater and mitigate ash storage ponds. Our mission is to create energyefficient solutions and offer the best engineering service and products to our customer. Fly ash is captured and removed from the flue gases by economiser, airpreheater and electrostatic precipitator esp. Ash storage silos can be constructed for both fly ash and bottom ash applications. Dry ash collection at coal fired power plants and potential for wte.
Andritz ash handling systems include conveyors and other equipment necessary for removal of bottom ash and fly ash from the power boiler. Up to now the mac system has been installed widely and successfully at coalfired power stations. Working of ash handling system in thermal power plant. Pressurized pneumatic ash conveying may also be employed.
Rendition of a ucc nuveyor system for a utility boiler, including gravity. United conveyor specializes in a number of vibrationbased systems for eliminating the storage of bottom ash in ponds. Denmark the authorities developed common rules for handling contaminated soil and. 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.