• 한국신재생에너지학회:학술대회논문집
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• 2008.10a
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• pp.145-148
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• 2008

Fuel flexibility of CFBC boiler was examined. Combustion characteristics of low grade coal, coal sludge, coal RDF mixture and RDF were compared. The operation result of a commercial 130TPH CFBC co-generation boiler burning a low grade Chinese coal were analysed. Burning characteristics of coal/RDF mixture and coal and industrial sludge mixture were studied in a 0.1MWth scale CFBC test rig. Also RDF fuel were tested in a 8TPH CFBC test facility. Though fuel characteristics were different, the combustion modes were all very stable. The temperature were maintained in between $800-950^{\circ}C$.

• Plant Journal
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• v.8 no.1
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• pp.73-80
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• 2012

The structure and combustion characteristics, and the economic feasibility of the circulating fluidized bed combustion(CFBC) boiler using low grade coal were introduced. The economic feasibility is evaluated by comparing a 500 MW CFBC boiler power plant using low grade coal and a pulverized combustion boiler power plant with high grade coal. As the result of the evaluation, the pulverized coal combustion boiler power plant has an internal rate of return of 12.95%, 1,395.9 billion Korean won of net present value, and 6.26 years of payback period. On the other hand, CFBC boiler power plant has an internal rate of return of 13.54%, 1,704.3 billion Korean won of net present value, and 6.02 years payback period. Therefore, the CFBC boiler power plant has better feasibility in all aspects, as 0.59% higher of internal rate of return, 308.4 billion Korean won of higher net present value and 0.24 year of shorter payback period.

• Journal of Korea Society of Waste Management
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• v.35 no.8
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• pp.754-761
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• 2018

There is growing concern over the effects of global warning. In response, the power generation sector must consider a wider range of systems and fuels to generate power. One of the classes of solid fuels that is being increasingly developed is biomass. However, one of the most serious problems that biomass plants face is severe corrosion. To mitigate the problem, various approaches have been proposed in terms of additive utilization. This study is based on the results obtained during the co-combustion of wood chip and waste wood in a circulating fluidized bed boiler (CFBC boiler). The KCl concentration was reduced from 59.9 ppm to 3.9 ppm during the injection of ammonium sulfate, and NOx was reduced by 25.5 ppm from 30.6 ppm to 5.1 ppm. However, SOx increased by 110.2 ppm from 33.2 ppm to 143.4 ppm, and HCl increased by 71.5 ppm from 340.5 ppm to 412.0 ppm. Thus, we confirmed that the attitude of the superheater tube was reduced by 87 ~ 93%, and the injection of ammonium sulfate was effective in preventing high-temperature corrosion.

• Journal of the Korean Professional Engineers Association
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• v.23 no.4
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• pp.30-37
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• 1990

• Journal of the Korean Professional Engineers Association
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• v.23 no.3
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• pp.58-68
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• 1990

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.10a
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• pp.101-106
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• 2011

In the present paper, the phenomena of abnormal noise and vibration due to acoustic resonance of CFBC(Circulating Fluidized Bed Combustion) boiler was presented. The acoustic resonance which occurred in the gas path of CFBC boiler system was caused by coincidence of vortex shedding frequency of tube bank and acoustic natural frequency of duct and hopper. And, the phenomena of beating arose from the interference of two closed resonant waves at 66.4Hz and 70.8Hz. There are two control methods for acoustic resonance in this system. The first method is to change the vortex shedding frequency from the structural alterations on the tube bank. And the second method is to change the acoustic natural frequency of the gas path with the installation of anti-noise baffles. The second one which is relatively easy to apply, was adapted in this study. As a result, the noise and vibration level have been decreased by 41dB and 94% at 66.4Hz, respectively. And the improvement of noise and vibration at 70.8Hz was identified by sensory evaluation.

• 한국연소학회:학술대회논문집
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• 2005.10a
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• pp.71-77
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• 2005

Combustion of RDF and wastewater sludge was performed in a 0.1MWth bench scale circulating fluidized bed combustor(CFBC), Combustion characteristics of the RDF and sludge mixture demonstrated stable combustion conditions. Component analysis, Combustion characteristics was measured before and after the test, and applications for commercial 1MWe CFBC boiler were prepared. The release of hazardous components such as $SO_2$ and HCl was relatively low values of 50 and 150ppm, respectively.

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.E2
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• pp.67-74
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• 2005

Domestic anthracite contains a large amount of fine particles, which causes to fire the back side of the boiler and to form the clinker deteriorating the combustion efficiency. At this time, the fine limestone adsorbents for a desulphurization agent may be used to facilitate an aggravation of the boiler, so that fine mode of limestone (<0.1mm) has been used no more than $25\%$ in local power stations of Korea. The present test carried out with an in-situ boiler, however, showed that higher content $(up\;to\;50\%)$ of fine limestone particles did not entail any mal-function. In addition, the desulphurization was found to be as good as the old mode of limestone adsorbents.

• Journal of the Korean Recycled Construction Resources Institute
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• v.11 no.4
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• pp.324-331
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• 2023

In this study, the hydration and carbonation properties of circulating fluidized bed boiler (CFBC) ash with different free-CaO contents were investigated. In addition, the possibility of utilizing CFBC ash with a high free-CaO content as a cementitious material was investigated by carbonation curing as a pretreatment. The CFBC ash with high free-CaO content exhibited rapid setting behavior and low early compressive strength when mixed with cement. For CFBC ash with high free-CaO content, carbon dioxide capture increased with the duration of carbonization curing. In addition, the free-CaO value decreased together, indicating that the free-CaO reacted with carbon dioxide. When the CFBC ash with high free-CaO content was pretreated by carbonation, no fresh set appeared, and the initial compressive strength was improved. From the results of this study, it is confirmed that CFBC ash with high free-CaO content has a high potential to be utilized as a cementitious material through proper carbonation curing.

• Journal of the Korean Ceramic Society
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• v.54 no.2
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• pp.128-136
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• 2017

Fly ash from a circulating fluidized bed combustion boiler (CFBC fly ash) is very different in mineralogical composition, chemical composition, and morphology from coal ash from traditional pulverized fuel firing because of many differences in their combustion processes. The main minerals of CFBC fly ash are lime and anhydrous gypsum; however, due to the fuel type, the strength development of CFBC fly ash is affected by minor components of active $SiO_2$ and $Al_2O_3$. The initial hydration product of the circulating fluidized bed combustion fly ash (B CFBC ash) using petro coke as a fuel is Portlandite which becomes gypsum after 7 days. Due to the structural features of the portlandite and gypsum, the self-cementitious strength of B CFBC ash was low. While the hydration products of the circulating fluidized bed combustion fly ash (A CFBC ash) using bituminous coal as a fuel were initially portlandite and ettringite, after 7 days the hydration products were gypsum and C-S-H. Due to the structural features of ettringite and C-S-H, A CFBC ash showed a certain degree of self-cementitious strength.