Enhanced reactivity of geopolymers produced from fluidized bed combustion bottom ash

Though the majority of research on fly ash has proved its worth as a construction material, the utility of bottom ash is yet questionable due to its generation during the pulverized combustion process. The bottom ash produced during the fluidized bed combustion (FBC) process is attracting more attention due to the novelty of coal combustion technology. But, to establish its suitability as construction material, it is necessary to characterize it thoroughly with respect to the geotechnical as well as mineralogical points of view. For fulfilling these objectives, the present study mainly aims at characterizing the FBC bottom ash and its comparison with pulverized coal combustion (PCC) bottom ash, collected from the same origin of coal. Suitability of FBC bottom ash as a dike filter material in contrast to PCC bottom ash in replacing traditional filter material such as sand was also studied. The suitability criteria for utilization of both bottom ash and river sand as filter material on pond ash as a base material were evaluated, and both river sand and FBC bottom ash were found to be satisfactory. The study shows that FBC bottom ash is a better geo-material than PCC bottom ash, and it could be highly recommended as an alternative suitable filter material for constructing ash dikes in place of conventional sand.

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Use of circulating fluidized bed combustion bottom ash as a secondary activator in high-volume slag cement

Construction and Building Materials ◽

10.1016/j.conbuildmat.2019.117240 ◽

2020 ◽

Vol 234 ◽

pp. 117240 ◽

Cited By ~ 1

Author(s):

Hyo Kyoung Lee ◽

Sang-Min Jeon ◽

Bang Yeon Lee ◽

Hyeong-Ki Kim

Keyword(s):

Fluidized Bed ◽

Circulating Fluidized Bed ◽

Bottom Ash ◽

High Volume ◽

Fluidized Bed Combustion ◽

Slag Cement ◽

Circulating Fluidized Bed Combustion

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Assessment of Sorbent Reactivation by Water Hydration for Fluidized Bed Combustion Application

17th International Conference on Fluidized Bed Combustion ◽

10.1115/fbc2003-110 ◽

2003 ◽

Author(s):

Fabio Montagnaro ◽

Piero Salatino ◽

Fabrizio Scala ◽

Yinghai Wu ◽

Edward Anthony ◽

...

Keyword(s):

Fluidized Bed ◽

Liquid Water ◽

Operating Cost ◽

Bottom Ash ◽

Full Scale ◽

Fluidized Bed Combustion ◽

Research Activities ◽

Combination Of Methods ◽

Influence Of Hydration

Disposal of FBC solid residues currently represents one of the major issues in FBC design and operation, and contributes significantly to FBC operating cost. This issue has triggered research activities on the enhancement of sorbent utilization for in-situ sulfur uptake. The present study addresses the effectiveness of the reactivation by liquid water hydration of FB spent sorbents. Two materials are considered in the study, namely bottom ash from the operation of a full-scale utility FB boiler and the raw commercial limestone used in the same boiler. Hydration-reactivation tests were carried out at temperatures of 40°C and 80°C and for curing times ranging from 15min to 2d, depending on the sample. The influence of hydration conditions on the enhancement of sulfur utilization has been assessed. A combination of methods has been used to characterize the properties of liquid water-hydrated materials.

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Partitioning of Trace Elements During Fluidized Bed Combustion of High Ash Content Lignite

18th International Conference on Fluidized Bed Combustion ◽

10.1115/fbc2005-78068 ◽

2005 ◽

Cited By ~ 1

Author(s):

Nevin Selc¸uk ◽

Yusuf Gogebakan ◽

Zuhal Gogebakan

Keyword(s):

Trace Elements ◽

Fly Ash ◽

Fluidized Bed ◽

Inductively Coupled Plasma ◽

Bottom Ash ◽

Ash Content ◽

Fluidized Bed Combustion ◽

Test Rig ◽

Minor Elements ◽

Element Partitioning

The behavior of 20 trace elements (As, B, Ba, Cd, Co, Cr, Cu, Hg, Li, Mn, Mo, Ni, P, Pb, Sb, Se, Sn, Tl, V, Zn) and 8 major and minor elements (Al, Ca, Fe, K, Mg, Na, Si, Ti) during the combustion of high ash content lignite with and without limestone addition have been investigated in the 0.3 MWt Middle East Technical University (METU) Atmospheric Bubbling Fluidized Bed Combustor (ABFBC) Test Rig. Experiments were performed without fines recycle. Inert bed material utilized in the experiments was bed ash obtained previously from the combustion of the same lignite without limestone addition in the same test rig. Concentrations of trace elements in coal, limestone, bottom ash, cyclone ash and filter ash were determined by Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). Measurements show that the distribution of major and minor elements follows the ash split between the bottom ash and fly ash and that the major proportion of most of the trace elements (As, Ba, Cr, Hg, Li, Mo, Ni, Sn, V, Zn) are recovered in fly ash. Comparisons between the trace element partitioning of the runs with and without limestone addition reveal that addition of limestone shifts the partitioning of Ba, Cr, Hg, Mo, Ni, Sn, V, Zn from bottom ash to fly ash.

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PROKNOW-C: DA SELEÇÃO DE UM PORTFÓLIO DE ARTIGOS A ANÁLISE SISTÊMICA SOBRE BLOCOS DE TERRA COMPRIMIDA

Pensar Acadêmico ◽

10.21576/pa.2019v17i3.838 ◽

2019 ◽

Vol 17 (3) ◽

Author(s):

Sâmara França ◽

Mariana Rezende Schuab ◽

Kastelli Pacheco Sperandio ◽

Rogério Cabral de Azevedo ◽

Maria Cristina Ramos de Carvalho ◽

...

Keyword(s):

Fluidized Bed ◽

Circulating Fluidized Bed ◽

Bottom Ash ◽

Fluidized Bed Combustion ◽

Circulating Fluidized Bed Combustion

Blocos de terra compactada são elementos de alvenaria feitos a partir de terra estabilizada e adensada. Estes materiais se destacam no quesito sustentabilidade por dispensarem a fase de queima em sua produção. A estabilização química dos blocos pode ser realizada através da ativação alcalina que consiste na obtenção de ligantes a partir de materiais aluminossilicatos em uma solução fortemente alcalina. A ativação alcalina também é vista como ambientalmente correta devido a sua baixa emissão de gases do efeito estufa. Entre os materiais precursores da ativação alcalina estão as cinzas volantes devido a sua composição química. Diante desse contexto, o objetivo deste trabalho é montar um portfólio de artigos científicos sobre blocos de terra compactado com adição de cinzas orgânicas e ativação alcalina, fazer análise bibliométrica e sistêmica dos artigos. O portfólio bibliográfico resultante é composto por 4 artigos relevantes e alinhados com o tema. Dentro da análise bibliométrica pode-se destacar o artigo “Feasibility o fmanufacturing geopolymer bricks using circulating fluidized bed combustion bottom ash” como mais relevante. Em relação a análise sistêmica elencou-se 5 lentes para a discussão dos artigos e a partir disso pode-se observar oportunidades para futuras pesquisas.

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Preparation of geopolymer from fluidized bed combustion bottom ash

Journal of Materials Processing Technology ◽

10.1016/j.jmatprotec.2007.09.008 ◽

2008 ◽

Vol 200 (1-3) ◽

pp. 265-270 ◽

Cited By ~ 48

Author(s):

R. Slavik ◽

V. Bednarik ◽

M. Vondruska ◽

A. Nemec

Keyword(s):

Fluidized Bed ◽

Bottom Ash ◽

Fluidized Bed Combustion

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Ash Cooling Screws: A Retrospective and Looking Ahead

17th International Conference on Fluidized Bed Combustion ◽

10.1115/fbc2003-100 ◽

2003 ◽

Author(s):

Jeff W. Kerner ◽

Gary W. Stetler

Keyword(s):

Fluidized Bed ◽

Food Industry ◽

Bottom Ash ◽

Fluidized Bed Combustion ◽

Maintenance Costs ◽

Look Ahead ◽

Look Back ◽

Operating Units

The first commercial screw cooler on record for cooling bottom ash from fluidized bed combustion (FBC) boilers was installed in 1979. Since then, over 300 ash screw cooler (ASC) machines have been used for this duty worldwide. The relatively quick upsurge in developing and building FBC boilers in the early 1980’s forced the industry to select existing cooling screw designs, typically used in less severe services in the chemical, grain, plastics and food industry. At the time, these were the only reasonable and readily available machines thought capable of handling abrasive, corrosive and extremely hot bottom ash. The extreme difficulties of operating and maintaining these units in this service quickly became apparent, but only after quite a number of initial designs had already been designed, purchased and installed. Today, 23 years later, both the manufacturers and users of ASC’s can look back and point to installations where, thanks to communication and cooperation between operators and the manufacturer, operating units and their installations have been successfully modified, resulting in smoother operation and much less frequent maintenance. New units can incorporate a range of features, depending upon the anticipated ash quality. As a result, ASC are now reportedly ranked low on the list of FBC operator’s and manager’s concerns. This paper will address what has been learned by both manufacturers and operators. The results of a survey of the operating and maintenance experience as well as maintenance costs of a wide sample of ASC users will be presented. A look ahead as to where ash screw cooler technology is moving is addressed, with help and continued input from current users of the equipment.

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