Compared to a pulverized coal boiler, circulating fluidized bed (CFB) boiler may face greater risk if sudden power failure accident happens due the massive materials in its main loop. In this study, numerical simulation is conducted analyze heat transfer process of stationary and estimate temperature based on real that happened 170 t/h CFB boiler. The results are consistent well with measuremen...

Ultra-supercritical circulating fluidized bed (CFB) boiler combustion technology has the advantages of environmental protection and good commercialization. As one key aspects in ultra-supercritical CFB technology, water wall system directly determines whether can safely effectively transform heat energy. This paper studies thermal–hydraulic characteristics designed a 700 MWe boiler, largest tha...

−The information of particle cluster dynamics is necessary for improving the performance of a circulating fluidized bed system. The main objective of this study is to compare the particle cluster diameters and concentrations from computational fluid dynamics simulation results between circulating fluidized bed riser and downer. The calculation methodologies are based on the concept of kinetic t...

A low-pressure plasma surface treatment of polymeric powders was carried out in a circulating fluidized bed (CFB) reactor (10 mm-I.D. × 800 mm-high) with CF4 glow discharge. The effects of solid circulation rate, treatment time and radio frequency (rf) power of plasma on fluorination of high-density polyethylene (HDPE) powders have been determined. X-ray photoelectron spectroscopy (XPS) and the...

In order to improve the traditional freezing crystallization process of calcium nitrate in nitric phosphate process, crystal growth experiments by adding Ca(NO3)2·4H2O seeds in supersaturated calcium nitrate solution in a Circulating Fluidized Bed (CFB) crystallizer were carried out on crystal growth kinetics. The results showed that the growth of C...

Fuel feeding and inhomogeneity of fuel typically cause process fluctuations in the circulating fluidized bed (CFB) boilers. If control systems fail to compensate the fluctuations, the whole plant will suffer from fluctuations that are reinforced by the closed-loop controls. Accurate estimates of fuel consumption among other factors are needed for control systems operation. In this paper we addr...

Bed particle layer and crack characteristics at different ages were studied for quartz K-feldspar bed particles from a 30 MWth bubbling fluidized 90 circulating bed, both using woody biomass as fuel. X-ray microtomography (XMT) was utilized to determine the distribution on particles' surface. For each type, average thickness well volume fractions of layers entire determined three by utilizing X...

In view of the current status catalytic cracking flue gas treatment, it is necessary to study flow environment desulfurization ash particles, which are a type Geldart C particle, in circulating fluidized bed (CFB) for semi-dry desulphurization using CFB technology. This investigated characteristics particles riser with an inner diameter 70 mm and height 12.6 m, at velocity 4–7 m/s solids circul...

• Oxy-fuel combustion is a simple method for CO 2 capture. The emissions are negative if captured from of -neutral biomass. To change CFB boiler to oxy-fuel, heat must be moved furnace backpass. Oxy-combustion by flue-gas recirculation capture applied an existing, already -neutral, biomass-fired circulating fluidized bed (CFB) boiler, thus resulting in emissions. required oxygen concentration d...